Gnubee/v4.15 #3

hvontres · 2018-05-15T05:06:51Z

Neil, Here is the initial support for the GB-PC2 and some enhancements to the defconfig files from my working tree.

- Add gbpc2.dts based on GB-PC2.dts from https://gogs.librecmc.org/ldpinney/GnuBee-libreCMC - add config DTB_GNUBEE2 opttion to Kconfig - add gnubee2_defconfig

Aded onshot,disk,heartbeat and cpu triggers for system LEDs

neilbrown · 2018-06-06T22:10:22Z

Sorry, I only just noticed this - my github email wasn't getting filed correctly :-(
I looks generally OK, so I've pulled it.
I have PC2 now so I hope to test it soonish and see how it goes.
Thanks!

hvontres · 2018-06-06T23:24:00Z

You're welcome. I have been running mine on this configuration for a couple of weeks now and other than the rsync memory leak, I haven't seen any issues yet. There were some additional changes to the dtb file from the original tree that looked like they deal with the onboard ehternet switch, but I don't know enough about dtb files to even have a clue where to start. Thank you for all of the effort you have put in so far, Henry

…

On Wed, Jun 6, 2018 at 3:10 PM, NeilBrown ***@***.***> wrote: Sorry, I only just noticed this - my github email wasn't getting filed correctly :-( I looks generally OK, so I've pulled it. I have PC2 now so I hope to test it soonish and see how it goes. Thanks! — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#3 (comment)>, or mute the thread <https:/notifications/unsubscribe-auth/ACouH7u3DO31ddl6qqMg1jj5AzMYHo3bks5t6FNPgaJpZM4T-5S2> .

…sfers This bug happens only when the UDC needs to sleep during usb_ep_dequeue, as is the case for (at least) dwc3. [ 382.200896] BUG: scheduling while atomic: screen/1808/0x00000100 [ 382.207124] 4 locks held by screen/1808: [ 382.211266] #0: (rcu_callback){....}, at: [<c10b4ff0>] rcu_process_callbacks+0x260/0x440 [ 382.219949] #1: (rcu_read_lock_sched){....}, at: [<c1358ba0>] percpu_ref_switch_to_atomic_rcu+0xb0/0x130 [ 382.230034] #2: (&(&ctx->ctx_lock)->rlock){....}, at: [<c11f0c73>] free_ioctx_users+0x23/0xd0 [ 382.230096] #3: (&(&ffs->eps_lock)->rlock){....}, at: [<f81e7710>] ffs_aio_cancel+0x20/0x60 [usb_f_fs] [ 382.230160] Modules linked in: usb_f_fs libcomposite configfs bnep btsdio bluetooth ecdh_generic brcmfmac brcmutil intel_powerclamp coretemp dwc3 kvm_intel ulpi udc_core kvm irqbypass crc32_pclmul crc32c_intel pcbc dwc3_pci aesni_intel aes_i586 crypto_simd cryptd ehci_pci ehci_hcd gpio_keys usbcore basincove_gpadc industrialio usb_common [ 382.230407] CPU: 1 PID: 1808 Comm: screen Not tainted 4.14.0-edison+ torvalds#117 [ 382.230416] Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48 [ 382.230425] Call Trace: [ 382.230438] <SOFTIRQ> [ 382.230466] dump_stack+0x47/0x62 [ 382.230498] __schedule_bug+0x61/0x80 [ 382.230522] __schedule+0x43/0x7a0 [ 382.230587] schedule+0x5f/0x70 [ 382.230625] dwc3_gadget_ep_dequeue+0x14c/0x270 [dwc3] [ 382.230669] ? do_wait_intr_irq+0x70/0x70 [ 382.230724] usb_ep_dequeue+0x19/0x90 [udc_core] [ 382.230770] ffs_aio_cancel+0x37/0x60 [usb_f_fs] [ 382.230798] kiocb_cancel+0x31/0x40 [ 382.230822] free_ioctx_users+0x4d/0xd0 [ 382.230858] percpu_ref_switch_to_atomic_rcu+0x10a/0x130 [ 382.230881] ? percpu_ref_exit+0x40/0x40 [ 382.230904] rcu_process_callbacks+0x2b3/0x440 [ 382.230965] __do_softirq+0xf8/0x26b [ 382.231011] ? __softirqentry_text_start+0x8/0x8 [ 382.231033] do_softirq_own_stack+0x22/0x30 [ 382.231042] </SOFTIRQ> [ 382.231071] irq_exit+0x45/0xc0 [ 382.231089] smp_apic_timer_interrupt+0x13c/0x150 [ 382.231118] apic_timer_interrupt+0x35/0x3c [ 382.231132] EIP: __copy_user_ll+0xe2/0xf0 [ 382.231142] EFLAGS: 00210293 CPU: 1 [ 382.231154] EAX: bfd4508c EBX: 00000004 ECX: 00000003 EDX: f3d8fe50 [ 382.231165] ESI: f3d8fe51 EDI: bfd4508d EBP: f3d8fe14 ESP: f3d8fe08 [ 382.231176] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 382.231265] core_sys_select+0x25f/0x320 [ 382.231346] ? __wake_up_common_lock+0x62/0x80 [ 382.231399] ? tty_ldisc_deref+0x13/0x20 [ 382.231438] ? ldsem_up_read+0x1b/0x40 [ 382.231459] ? tty_ldisc_deref+0x13/0x20 [ 382.231479] ? tty_write+0x29f/0x2e0 [ 382.231514] ? n_tty_ioctl+0xe0/0xe0 [ 382.231541] ? tty_write_unlock+0x30/0x30 [ 382.231566] ? __vfs_write+0x22/0x110 [ 382.231604] ? security_file_permission+0x2f/0xd0 [ 382.231635] ? rw_verify_area+0xac/0x120 [ 382.231677] ? vfs_write+0x103/0x180 [ 382.231711] SyS_select+0x87/0xc0 [ 382.231739] ? SyS_write+0x42/0x90 [ 382.231781] do_fast_syscall_32+0xd6/0x1a0 [ 382.231836] entry_SYSENTER_32+0x47/0x71 [ 382.231848] EIP: 0xb7f75b05 [ 382.231857] EFLAGS: 00000246 CPU: 1 [ 382.231868] EAX: ffffffda EBX: 00000400 ECX: bfd4508c EDX: bfd4510c [ 382.231878] ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: bfd45020 [ 382.231889] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b [ 382.232281] softirq: huh, entered softirq 9 RCU c10b4d90 with preempt_count 00000100, exited with 00000000? Tested-by: Sam Protsenko <[email protected]> Signed-off-by: Vincent Pelletier <[email protected]> Signed-off-by: Felipe Balbi <[email protected]>

Crash dump shows following instructions crash> bt PID: 0 TASK: ffffffffbe412480 CPU: 0 COMMAND: "swapper/0" #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a #4 [ffff891ee00039e0] no_context at ffffffffbd074643 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e torvalds#6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64 torvalds#7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a torvalds#8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8 torvalds#9 [ffff891ee0003b50] page_fault at ffffffffbda01925 [exception RIP: qlt_schedule_sess_for_deletion+15] RIP: ffffffffc02e526f RSP: ffff891ee0003c08 RFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffc0307847 RDX: 00000000000020e6 RSI: ffff891edbc377c8 RDI: 0000000000000000 RBP: ffff891ee0003c18 R8: ffffffffc02f0b20 R9: 0000000000000250 R10: 0000000000000258 R11: 000000000000b780 R12: ffff891ed9b43000 R13: 00000000000000f0 R14: 0000000000000006 R15: ffff891edbc377c8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx] torvalds#11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx] torvalds#12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx] torvalds#13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx] torvalds#14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59 torvalds#15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02 torvalds#16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90 torvalds#17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984 torvalds#18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5 torvalds#19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18 --- <IRQ stack> --- torvalds#20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e [exception RIP: unknown or invalid address] RIP: 000000000000001f RSP: 0000000000000000 RFLAGS: fff3b8c2091ebb3f RAX: ffffbba5a0000200 RBX: 0000be8cdfa8f9fa RCX: 0000000000000018 RDX: 0000000000000101 RSI: 000000000000015d RDI: 0000000000000193 RBP: 0000000000000083 R8: ffffffffbe403e38 R9: 0000000000000002 R10: 0000000000000000 R11: ffffffffbe56b820 R12: ffff891ee001cf00 R13: ffffffffbd11c0a4 R14: ffffffffbe403d60 R15: 0000000000000001 ORIG_RAX: ffff891ee0022ac0 CS: 0000 SS: ffffffffffffffb9 bt: WARNING: possibly bogus exception frame torvalds#21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd torvalds#22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907 torvalds#23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3 torvalds#24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42 torvalds#25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3 torvalds#26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa torvalds#27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca torvalds#28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675 torvalds#29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb torvalds#30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5 Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login") Cc: <[email protected]> # v4.17+ Signed-off-by: Chuck Anderson <[email protected]> Signed-off-by: Himanshu Madhani <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>

When fq_codel_init fails, qdisc_create_dflt will cleanup by using qdisc_destroy. This function calls the ->reset() op prior to calling the ->destroy() op. Unfortunately, during the failure flow for sch_fq_codel, the ->flows parameter is not initialized, so the fq_codel_reset function will null pointer dereference. kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 kernel: IP: fq_codel_reset+0x58/0xd0 [sch_fq_codel] kernel: PGD 0 P4D 0 kernel: Oops: 0000 [#1] SMP PTI kernel: Modules linked in: i40iw i40e(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack tun bridge stp llc devlink ebtable_filter ebtables ip6table_filter ip6_tables rpcrdma ib_isert iscsi_target_mod sunrpc ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel intel_cstate iTCO_wdt iTCO_vendor_support intel_uncore ib_core intel_rapl_perf mei_me mei joydev i2c_i801 lpc_ich ioatdma shpchp wmi sch_fq_codel xfs libcrc32c mgag200 ixgbe drm_kms_helper isci ttm firewire_ohci kernel: mdio drm igb libsas crc32c_intel firewire_core ptp pps_core scsi_transport_sas crc_itu_t dca i2c_algo_bit ipmi_si ipmi_devintf ipmi_msghandler [last unloaded: i40e] kernel: CPU: 10 PID: 4219 Comm: ip Tainted: G OE 4.16.13custom-fq-codel-test+ #3 kernel: Hardware name: Intel Corporation S2600CO/S2600CO, BIOS SE5C600.86B.02.05.0004.051120151007 05/11/2015 kernel: RIP: 0010:fq_codel_reset+0x58/0xd0 [sch_fq_codel] kernel: RSP: 0018:ffffbfbf4c1fb620 EFLAGS: 00010246 kernel: RAX: 0000000000000400 RBX: 0000000000000000 RCX: 00000000000005b9 kernel: RDX: 0000000000000000 RSI: ffff9d03264a60c0 RDI: ffff9cfd17b31c00 kernel: RBP: 0000000000000001 R08: 00000000000260c0 R09: ffffffffb679c3e9 kernel: R10: fffff1dab06a0e80 R11: ffff9cfd163af800 R12: ffff9cfd17b31c00 kernel: R13: 0000000000000001 R14: ffff9cfd153de600 R15: 0000000000000001 kernel: FS: 00007fdec2f92800(0000) GS:ffff9d0326480000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000000008 CR3: 0000000c1956a006 CR4: 00000000000606e0 kernel: Call Trace: kernel: qdisc_destroy+0x56/0x140 kernel: qdisc_create_dflt+0x8b/0xb0 kernel: mq_init+0xc1/0xf0 kernel: qdisc_create_dflt+0x5a/0xb0 kernel: dev_activate+0x205/0x230 kernel: __dev_open+0xf5/0x160 kernel: __dev_change_flags+0x1a3/0x210 kernel: dev_change_flags+0x21/0x60 kernel: do_setlink+0x660/0xdf0 kernel: ? down_trylock+0x25/0x30 kernel: ? xfs_buf_trylock+0x1a/0xd0 [xfs] kernel: ? rtnl_newlink+0x816/0x990 kernel: ? _xfs_buf_find+0x327/0x580 [xfs] kernel: ? _cond_resched+0x15/0x30 kernel: ? kmem_cache_alloc+0x20/0x1b0 kernel: ? rtnetlink_rcv_msg+0x200/0x2f0 kernel: ? rtnl_calcit.isra.30+0x100/0x100 kernel: ? netlink_rcv_skb+0x4c/0x120 kernel: ? netlink_unicast+0x19e/0x260 kernel: ? netlink_sendmsg+0x1ff/0x3c0 kernel: ? sock_sendmsg+0x36/0x40 kernel: ? ___sys_sendmsg+0x295/0x2f0 kernel: ? ebitmap_cmp+0x6d/0x90 kernel: ? dev_get_by_name_rcu+0x73/0x90 kernel: ? skb_dequeue+0x52/0x60 kernel: ? __inode_wait_for_writeback+0x7f/0xf0 kernel: ? bit_waitqueue+0x30/0x30 kernel: ? fsnotify_grab_connector+0x3c/0x60 kernel: ? __sys_sendmsg+0x51/0x90 kernel: ? do_syscall_64+0x74/0x180 kernel: ? entry_SYSCALL_64_after_hwframe+0x3d/0xa2 kernel: Code: 00 00 48 89 87 00 02 00 00 8b 87 a0 01 00 00 85 c0 0f 84 84 00 00 00 31 ed 48 63 dd 83 c5 01 48 c1 e3 06 49 03 9c 24 90 01 00 00 <48> 8b 73 08 48 8b 3b e8 6c 9a 4f f6 48 8d 43 10 48 c7 03 00 00 kernel: RIP: fq_codel_reset+0x58/0xd0 [sch_fq_codel] RSP: ffffbfbf4c1fb620 kernel: CR2: 0000000000000008 kernel: ---[ end trace e81a62bede66274e ]--- This is caused because flows_cnt is non-zero, but flows hasn't been initialized. fq_codel_init has left the private data in a partially initialized state. To fix this, reset flows_cnt to 0 when we fail to initialize. Additionally, to make the state more consistent, also cleanup the flows pointer when the allocation of backlogs fails. This fixes the NULL pointer dereference, since both the for-loop and memset in fq_codel_reset will be no-ops when flow_cnt is zero. Signed-off-by: Jacob Keller <[email protected]> Signed-off-by: David S. Miller <[email protected]>

…' messages Multiline statements with invalid %p<foo> uses produce multiple warnings. Fix that. e.g.: $ cat t_block.c void foo(void) { MY_DEBUG(drv->foo, "%pk", foo->boo); } $ ./scripts/checkpatch.pl -f t_block.c WARNING: Missing or malformed SPDX-License-Identifier tag in line 1 #1: FILE: t_block.c:1: +void foo(void) WARNING: Invalid vsprintf pointer extension '%pk' #3: FILE: t_block.c:3: + MY_DEBUG(drv->foo, + "%pk", + foo->boo); WARNING: Invalid vsprintf pointer extension '%pk' #3: FILE: t_block.c:3: + MY_DEBUG(drv->foo, + "%pk", + foo->boo); total: 0 errors, 3 warnings, 6 lines checked NOTE: For some of the reported defects, checkpatch may be able to mechanically convert to the typical style using --fix or --fix-inplace. t_block.c has style problems, please review. NOTE: If any of the errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Joe Perches <[email protected]> Cc: "Tobin C. Harding" <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

commit 5c64576 upstream. syzkaller reports for wrong rtnl_lock usage in sync code [1] and [2] We have 2 problems in start_sync_thread if error path is taken, eg. on memory allocation error or failure to configure sockets for mcast group or addr/port binding: 1. recursive locking: holding rtnl_lock while calling sock_release which in turn calls again rtnl_lock in ip_mc_drop_socket to leave the mcast group, as noticed by Florian Westphal. Additionally, sock_release can not be called while holding sync_mutex (ABBA deadlock). 2. task hung: holding rtnl_lock while calling kthread_stop to stop the running kthreads. As the kthreads do the same to leave the mcast group (sock_release -> ip_mc_drop_socket -> rtnl_lock) they hang. Fix the problems by calling rtnl_unlock early in the error path, now sock_release is called after unlocking both mutexes. Problem 3 (task hung reported by syzkaller [2]) is variant of problem 2: use _trylock to prevent one user to call rtnl_lock and then while waiting for sync_mutex to block kthreads that execute sock_release when they are stopped by stop_sync_thread. [1] IPVS: stopping backup sync thread 4500 ... WARNING: possible recursive locking detected 4.16.0-rc7+ #3 Not tainted -------------------------------------------- syzkaller688027/4497 is trying to acquire lock: (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 but task is already holding lock: IPVS: stopping backup sync thread 4495 ... (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(rtnl_mutex); lock(rtnl_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syzkaller688027/4497: #0: (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 #1: (ipvs->sync_mutex){+.+.}, at: [<00000000703f78e3>] do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388 stack backtrace: CPU: 1 PID: 4497 Comm: syzkaller688027 Not tainted 4.16.0-rc7+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 print_deadlock_bug kernel/locking/lockdep.c:1761 [inline] check_deadlock kernel/locking/lockdep.c:1805 [inline] validate_chain kernel/locking/lockdep.c:2401 [inline] __lock_acquire+0xe8f/0x3e00 kernel/locking/lockdep.c:3431 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 ip_mc_drop_socket+0x88/0x230 net/ipv4/igmp.c:2643 inet_release+0x4e/0x1c0 net/ipv4/af_inet.c:413 sock_release+0x8d/0x1e0 net/socket.c:595 start_sync_thread+0x2213/0x2b70 net/netfilter/ipvs/ip_vs_sync.c:1924 do_ip_vs_set_ctl+0x1139/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2389 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1261 udp_setsockopt+0x45/0x80 net/ipv4/udp.c:2406 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x446a69 RSP: 002b:00007fa1c3a64da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446a69 RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006e29fc R08: 0000000000000018 R09: 0000000000000000 R10: 00000000200000c0 R11: 0000000000000246 R12: 00000000006e29f8 R13: 00676e697279656b R14: 00007fa1c3a659c0 R15: 00000000006e2b60 [2] IPVS: sync thread started: state = BACKUP, mcast_ifn = syz_tun, syncid = 4, id = 0 IPVS: stopping backup sync thread 25415 ... INFO: task syz-executor7:25421 blocked for more than 120 seconds. Not tainted 4.16.0-rc6+ torvalds#284 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D23688 25421 4408 0x00000004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440 schedule+0xf5/0x430 kernel/sched/core.c:3499 schedule_timeout+0x1a3/0x230 kernel/time/timer.c:1777 do_wait_for_common kernel/sched/completion.c:86 [inline] __wait_for_common kernel/sched/completion.c:107 [inline] wait_for_common kernel/sched/completion.c:118 [inline] wait_for_completion+0x415/0x770 kernel/sched/completion.c:139 kthread_stop+0x14a/0x7a0 kernel/kthread.c:530 stop_sync_thread+0x3d9/0x740 net/netfilter/ipvs/ip_vs_sync.c:1996 do_ip_vs_set_ctl+0x2b1/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2394 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1253 sctp_setsockopt+0x2ca/0x63e0 net/sctp/socket.c:4154 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:3039 SYSC_setsockopt net/socket.c:1850 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1829 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x454889 RSP: 002b:00007fc927626c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007fc9276276d4 RCX: 0000000000454889 RDX: 000000000000048c RSI: 0000000000000000 RDI: 0000000000000017 RBP: 000000000072bf58 R08: 0000000000000018 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000051c R14: 00000000006f9b40 R15: 0000000000000001 Showing all locks held in the system: 2 locks held by khungtaskd/868: #0: (rcu_read_lock){....}, at: [<00000000a1a8f002>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<00000000a1a8f002>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<0000000037c2f8f9>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 1 lock held by rsyslogd/4247: #0: (&f->f_pos_lock){+.+.}, at: [<000000000d8d6983>] __fdget_pos+0x12b/0x190 fs/file.c:765 2 locks held by getty/4338: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4339: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4340: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4341: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4342: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4343: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4344: #0: (&tty->ldisc_sem){++++}, at: [<00000000bee98654>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 3 locks held by kworker/0:5/6494: #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000a062b18e>] work_static include/linux/workqueue.h:198 [inline] #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000a062b18e>] set_work_data kernel/workqueue.c:619 [inline] #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000a062b18e>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<00000000a062b18e>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 #1: ((addr_chk_work).work){+.+.}, at: [<00000000278427d5>] process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 #2: (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 1 lock held by syz-executor7/25421: #0: (ipvs->sync_mutex){+.+.}, at: [<00000000d414a689>] do_ip_vs_set_ctl+0x277/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2393 2 locks held by syz-executor7/25427: #0: (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 #1: (ipvs->sync_mutex){+.+.}, at: [<00000000e6d48489>] do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388 1 lock held by syz-executor7/25435: #0: (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 1 lock held by ipvs-b:2:0/25415: #0: (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 Reported-and-tested-by: [email protected] Reported-and-tested-by: [email protected] Fixes: e0b26cc ("ipvs: call rtnl_lock early") Signed-off-by: Julian Anastasov <[email protected]> Signed-off-by: Simon Horman <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Cc: Zubin Mithra <[email protected]> Cc: Guenter Roeck <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…s found [ Upstream commit 72f17ba ] If an OVS_ATTR_NESTED attribute type is found while walking through netlink attributes, we call nlattr_set() recursively passing the length table for the following nested attributes, if different from the current one. However, once we're done with those sub-nested attributes, we should continue walking through attributes using the current table, instead of using the one related to the sub-nested attributes. For example, given this sequence: 1 OVS_KEY_ATTR_PRIORITY 2 OVS_KEY_ATTR_TUNNEL 3 OVS_TUNNEL_KEY_ATTR_ID 4 OVS_TUNNEL_KEY_ATTR_IPV4_SRC 5 OVS_TUNNEL_KEY_ATTR_IPV4_DST 6 OVS_TUNNEL_KEY_ATTR_TTL 7 OVS_TUNNEL_KEY_ATTR_TP_SRC 8 OVS_TUNNEL_KEY_ATTR_TP_DST 9 OVS_KEY_ATTR_IN_PORT 10 OVS_KEY_ATTR_SKB_MARK 11 OVS_KEY_ATTR_MPLS we switch to the 'ovs_tunnel_key_lens' table on attribute #3, and we don't switch back to 'ovs_key_lens' while setting attributes torvalds#9 to torvalds#11 in the sequence. As OVS_KEY_ATTR_MPLS evaluates to 21, and the array size of 'ovs_tunnel_key_lens' is 15, we also get this kind of KASan splat while accessing the wrong table: [ 7654.586496] ================================================================== [ 7654.594573] BUG: KASAN: global-out-of-bounds in nlattr_set+0x164/0xde9 [openvswitch] [ 7654.603214] Read of size 4 at addr ffffffffc169ecf0 by task handler29/87430 [ 7654.610983] [ 7654.612644] CPU: 21 PID: 87430 Comm: handler29 Kdump: loaded Not tainted 3.10.0-866.el7.test.x86_64 #1 [ 7654.623030] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016 [ 7654.631379] Call Trace: [ 7654.634108] [<ffffffffb65a7c50>] dump_stack+0x19/0x1b [ 7654.639843] [<ffffffffb53ff373>] print_address_description+0x33/0x290 [ 7654.647129] [<ffffffffc169b37b>] ? nlattr_set+0x164/0xde9 [openvswitch] [ 7654.654607] [<ffffffffb53ff812>] kasan_report.part.3+0x242/0x330 [ 7654.661406] [<ffffffffb53ff9b4>] __asan_report_load4_noabort+0x34/0x40 [ 7654.668789] [<ffffffffc169b37b>] nlattr_set+0x164/0xde9 [openvswitch] [ 7654.676076] [<ffffffffc167ef68>] ovs_nla_get_match+0x10c8/0x1900 [openvswitch] [ 7654.684234] [<ffffffffb61e9cc8>] ? genl_rcv+0x28/0x40 [ 7654.689968] [<ffffffffb61e7733>] ? netlink_unicast+0x3f3/0x590 [ 7654.696574] [<ffffffffc167dea0>] ? ovs_nla_put_tunnel_info+0xb0/0xb0 [openvswitch] [ 7654.705122] [<ffffffffb4f41b50>] ? unwind_get_return_address+0xb0/0xb0 [ 7654.712503] [<ffffffffb65d9355>] ? system_call_fastpath+0x1c/0x21 [ 7654.719401] [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370 [ 7654.726298] [<ffffffffb4f41d79>] ? update_stack_state+0x229/0x370 [ 7654.733195] [<ffffffffb53fe4b5>] ? kasan_unpoison_shadow+0x35/0x50 [ 7654.740187] [<ffffffffb53fe62a>] ? kasan_kmalloc+0xaa/0xe0 [ 7654.746406] [<ffffffffb53fec32>] ? kasan_slab_alloc+0x12/0x20 [ 7654.752914] [<ffffffffb53fe711>] ? memset+0x31/0x40 [ 7654.758456] [<ffffffffc165bf92>] ovs_flow_cmd_new+0x2b2/0xf00 [openvswitch] [snip] [ 7655.132484] The buggy address belongs to the variable: [ 7655.138226] ovs_tunnel_key_lens+0xf0/0xffffffffffffd400 [openvswitch] [ 7655.145507] [ 7655.147166] Memory state around the buggy address: [ 7655.152514] ffffffffc169eb80: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa [ 7655.160585] ffffffffc169ec00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 7655.168644] >ffffffffc169ec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa [ 7655.176701] ^ [ 7655.184372] ffffffffc169ed00: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 05 [ 7655.192431] ffffffffc169ed80: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00 [ 7655.200490] ================================================================== Reported-by: Hangbin Liu <[email protected]> Fixes: 982b527 ("openvswitch: Fix mask generation for nested attributes.") Signed-off-by: Stefano Brivio <[email protected]> Reviewed-by: Sabrina Dubroca <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 48fb6f4 upstream. Commit 65d8fc7 ("futex: Remove requirement for lock_page() in get_futex_key()") removed an unnecessary lock_page() with the side-effect that page->mapping needed to be treated very carefully. Two defensive warnings were added in case any assumption was missed and the first warning assumed a correct application would not alter a mapping backing a futex key. Since merging, it has not triggered for any unexpected case but Mark Rutland reported the following bug triggering due to the first warning. kernel BUG at kernel/futex.c:679! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 3695 Comm: syz-executor1 Not tainted 4.13.0-rc3-00020-g307fec773ba3 #3 Hardware name: linux,dummy-virt (DT) task: ffff80001e271780 task.stack: ffff000010908000 PC is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679 LR is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679 pc : [<ffff00000821ac14>] lr : [<ffff00000821ac14>] pstate: 80000145 The fact that it's a bug instead of a warning was due to an unrelated arm64 problem, but the warning itself triggered because the underlying mapping changed. This is an application issue but from a kernel perspective it's a recoverable situation and the warning is unnecessary so this patch removes the warning. The warning may potentially be triggered with the following test program from Mark although it may be necessary to adjust NR_FUTEX_THREADS to be a value smaller than the number of CPUs in the system. #include <linux/futex.h> #include <pthread.h> #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <sys/syscall.h> #include <sys/time.h> #include <unistd.h> #define NR_FUTEX_THREADS 16 pthread_t threads[NR_FUTEX_THREADS]; void *mem; #define MEM_PROT (PROT_READ | PROT_WRITE) #define MEM_SIZE 65536 static int futex_wrapper(int *uaddr, int op, int val, const struct timespec *timeout, int *uaddr2, int val3) { syscall(SYS_futex, uaddr, op, val, timeout, uaddr2, val3); } void *poll_futex(void *unused) { for (;;) { futex_wrapper(mem, FUTEX_CMP_REQUEUE_PI, 1, NULL, mem + 4, 1); } } int main(int argc, char *argv[]) { int i; mem = mmap(NULL, MEM_SIZE, MEM_PROT, MAP_SHARED | MAP_ANONYMOUS, -1, 0); printf("Mapping @ %p\n", mem); printf("Creating futex threads...\n"); for (i = 0; i < NR_FUTEX_THREADS; i++) pthread_create(&threads[i], NULL, poll_futex, NULL); printf("Flipping mapping...\n"); for (;;) { mmap(mem, MEM_SIZE, MEM_PROT, MAP_FIXED | MAP_SHARED | MAP_ANONYMOUS, -1, 0); } return 0; } Reported-and-tested-by: Mark Rutland <[email protected]> Signed-off-by: Mel Gorman <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Cc: [email protected] # 4.7+ Signed-off-by: Linus Torvalds <[email protected]> Cc: Ben Hutchings <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 2c0aa08 ] Scenario: 1. Port down and do fail over 2. Ap do rds_bind syscall PID: 47039 TASK: ffff89887e2fe640 CPU: 47 COMMAND: "kworker/u:6" #0 [ffff898e35f159f0] machine_kexec at ffffffff8103abf9 #1 [ffff898e35f15a60] crash_kexec at ffffffff810b96e3 #2 [ffff898e35f15b30] oops_end at ffffffff8150f518 #3 [ffff898e35f15b60] no_context at ffffffff8104854c #4 [ffff898e35f15ba0] __bad_area_nosemaphore at ffffffff81048675 #5 [ffff898e35f15bf0] bad_area_nosemaphore at ffffffff810487d3 torvalds#6 [ffff898e35f15c00] do_page_fault at ffffffff815120b8 torvalds#7 [ffff898e35f15d10] page_fault at ffffffff8150ea95 [exception RIP: unknown or invalid address] RIP: 0000000000000000 RSP: ffff898e35f15dc8 RFLAGS: 00010282 RAX: 00000000fffffffe RBX: ffff889b77f6fc00 RCX:ffffffff81c99d88 RDX: 0000000000000000 RSI: ffff896019ee08e8 RDI:ffff889b77f6fc00 RBP: ffff898e35f15df0 R8: ffff896019ee08c8 R9:0000000000000000 R10: 0000000000000400 R11: 0000000000000000 R12:ffff896019ee08c0 R13: ffff889b77f6fe68 R14: ffffffff81c99d80 R15: ffffffffa022a1e0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#8 [ffff898e35f15dc8] cma_ndev_work_handler at ffffffffa022a228 [rdma_cm] torvalds#9 [ffff898e35f15df8] process_one_work at ffffffff8108a7c6 torvalds#10 [ffff898e35f15e58] worker_thread at ffffffff8108bda0 torvalds#11 [ffff898e35f15ee8] kthread at ffffffff81090fe6 PID: 45659 TASK: ffff880d313d2500 CPU: 31 COMMAND: "oracle_45659_ap" #0 [ffff881024ccfc98] __schedule at ffffffff8150bac4 #1 [ffff881024ccfd40] schedule at ffffffff8150c2cf #2 [ffff881024ccfd50] __mutex_lock_slowpath at ffffffff8150cee7 #3 [ffff881024ccfdc0] mutex_lock at ffffffff8150cdeb #4 [ffff881024ccfde0] rdma_destroy_id at ffffffffa022a027 [rdma_cm] #5 [ffff881024ccfe10] rds_ib_laddr_check at ffffffffa0357857 [rds_rdma] torvalds#6 [ffff881024ccfe50] rds_trans_get_preferred at ffffffffa0324c2a [rds] torvalds#7 [ffff881024ccfe80] rds_bind at ffffffffa031d690 [rds] torvalds#8 [ffff881024ccfeb0] sys_bind at ffffffff8142a670 PID: 45659 PID: 47039 rds_ib_laddr_check /* create id_priv with a null event_handler */ rdma_create_id rdma_bind_addr cma_acquire_dev /* add id_priv to cma_dev->id_list */ cma_attach_to_dev cma_ndev_work_handler /* event_hanlder is null */ id_priv->id.event_handler Signed-off-by: Guanglei Li <[email protected]> Signed-off-by: Honglei Wang <[email protected]> Reviewed-by: Junxiao Bi <[email protected]> Reviewed-by: Yanjun Zhu <[email protected]> Reviewed-by: Leon Romanovsky <[email protected]> Acked-by: Santosh Shilimkar <[email protected]> Acked-by: Doug Ledford <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 2bbea6e ] when mounting an ISO filesystem sometimes (very rarely) the system hangs because of a race condition between two tasks. PID: 6766 TASK: ffff88007b2a6dd0 CPU: 0 COMMAND: "mount" #0 [ffff880078447ae0] __schedule at ffffffff8168d605 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod] #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50 torvalds#6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3 torvalds#7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs] torvalds#8 [ffff880078447da8] mount_bdev at ffffffff81202570 torvalds#9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs] torvalds#10 [ffff880078447e28] mount_fs at ffffffff81202d09 torvalds#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f torvalds#12 [ffff880078447ea8] do_mount at ffffffff81220fee torvalds#13 [ffff880078447f28] sys_mount at ffffffff812218d6 torvalds#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49 RIP: 00007fd9ea914e9a RSP: 00007ffd5d9bf648 RFLAGS: 00010246 RAX: 00000000000000a5 RBX: ffffffff81698c49 RCX: 0000000000000010 RDX: 00007fd9ec2bc210 RSI: 00007fd9ec2bc290 RDI: 00007fd9ec2bcf30 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000010 R10: 00000000c0ed0001 R11: 0000000000000206 R12: 00007fd9ec2bc040 R13: 00007fd9eb6b2380 R14: 00007fd9ec2bc210 R15: 00007fd9ec2bcf30 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b This task was trying to mount the cdrom. It allocated and configured a super_block struct and owned the write-lock for the super_block->s_umount rwsem. While exclusively owning the s_umount lock, it called sr_block_ioctl and waited to acquire the global sr_mutex lock. PID: 6785 TASK: ffff880078720fb0 CPU: 0 COMMAND: "systemd-udevd" #0 [ffff880078417898] __schedule at ffffffff8168d605 #1 [ffff880078417900] schedule at ffffffff8168dc59 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838 #4 [ffff8800784179d0] down_read at ffffffff8168cde0 #5 [ffff8800784179e8] get_super at ffffffff81201cc7 torvalds#6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de torvalds#7 [ffff880078417a40] flush_disk at ffffffff8123a94b torvalds#8 [ffff880078417a88] check_disk_change at ffffffff8123ab50 torvalds#9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom] torvalds#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod] torvalds#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86 torvalds#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65 torvalds#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b torvalds#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7 torvalds#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf torvalds#16 [ffff880078417d00] do_last at ffffffff8120d53d torvalds#17 [ffff880078417db0] path_openat at ffffffff8120e6b2 torvalds#18 [ffff880078417e48] do_filp_open at ffffffff8121082b torvalds#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33 torvalds#20 [ffff880078417f70] sys_open at ffffffff811fde4e torvalds#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49 RIP: 00007f29438b0c20 RSP: 00007ffc76624b78 RFLAGS: 00010246 RAX: 0000000000000002 RBX: ffffffff81698c49 RCX: 0000000000000000 RDX: 00007f2944a5fa70 RSI: 00000000000a0800 RDI: 00007f2944a5fa70 RBP: 00007f2944a5f540 R8: 0000000000000000 R9: 0000000000000020 R10: 00007f2943614c40 R11: 0000000000000246 R12: ffffffff811fde4e R13: ffff880078417f78 R14: 000000000000000c R15: 00007f2944a4b010 ORIG_RAX: 0000000000000002 CS: 0033 SS: 002b This task tried to open the cdrom device, the sr_block_open function acquired the global sr_mutex lock. The call to check_disk_change() then saw an event flag indicating a possible media change and tried to flush any cached data for the device. As part of the flush, it tried to acquire the super_block->s_umount lock associated with the cdrom device. This was the same super_block as created and locked by the previous task. The first task acquires the s_umount lock and then the sr_mutex_lock; the second task acquires the sr_mutex_lock and then the s_umount lock. This patch fixes the issue by moving check_disk_change() out of cdrom_open() and let the caller take care of it. Signed-off-by: Maurizio Lombardi <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit d546b67 ] spin_lock/unlock was used instead of spin_un/lock_irq in a procedure used in process space, on a spinlock which can be grabbed in an interrupt. This caused the stack trace below to be displayed (on kernel 4.17.0-rc1 compiled with Lock Debugging enabled): [ 154.661474] WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected [ 154.668909] 4.17.0-rc1-rdma_rc_mlx+ #3 Tainted: G I [ 154.675856] ----------------------------------------------------- [ 154.682706] modprobe/10159 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: [ 154.690254] 00000000f3b0e495 (&(&qp_table->lock)->rlock){+.+.}, at: mlx4_qp_remove+0x20/0x50 [mlx4_core] [ 154.700927] and this task is already holding: [ 154.707461] 0000000094373b5d (&(&cq->lock)->rlock/1){....}, at: destroy_qp_common+0x111/0x560 [mlx4_ib] [ 154.718028] which would create a new lock dependency: [ 154.723705] (&(&cq->lock)->rlock/1){....} -> (&(&qp_table->lock)->rlock){+.+.} [ 154.731922] but this new dependency connects a SOFTIRQ-irq-safe lock: [ 154.740798] (&(&cq->lock)->rlock){..-.} [ 154.740800] ... which became SOFTIRQ-irq-safe at: [ 154.752163] _raw_spin_lock_irqsave+0x3e/0x50 [ 154.757163] mlx4_ib_poll_cq+0x36/0x900 [mlx4_ib] [ 154.762554] ipoib_tx_poll+0x4a/0xf0 [ib_ipoib] ... to a SOFTIRQ-irq-unsafe lock: [ 154.815603] (&(&qp_table->lock)->rlock){+.+.} [ 154.815604] ... which became SOFTIRQ-irq-unsafe at: [ 154.827718] ... [ 154.827720] _raw_spin_lock+0x35/0x50 [ 154.833912] mlx4_qp_lookup+0x1e/0x50 [mlx4_core] [ 154.839302] mlx4_flow_attach+0x3f/0x3d0 [mlx4_core] Since mlx4_qp_lookup() is called only in process space, we can simply replace the spin_un/lock calls with spin_un/lock_irq calls. Fixes: 6dc06c0 ("net/mlx4: Fix the check in attaching steering rules") Signed-off-by: Jack Morgenstein <[email protected]> Signed-off-by: Tariq Toukan <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Daniel Casini got this warn while running a DL task here at RetisLab: [ 461.137582] ------------[ cut here ]------------ [ 461.137583] rq->clock_update_flags < RQCF_ACT_SKIP [ 461.137599] WARNING: CPU: 4 PID: 2354 at kernel/sched/sched.h:967 assert_clock_updated.isra.32.part.33+0x17/0x20 [a ton of modules] [ 461.137646] CPU: 4 PID: 2354 Comm: label_image Not tainted 4.18.0-rc4+ #3 [ 461.137647] Hardware name: ASUS All Series/Z87-K, BIOS 0801 09/02/2013 [ 461.137649] RIP: 0010:assert_clock_updated.isra.32.part.33+0x17/0x20 [ 461.137649] Code: ff 48 89 83 08 09 00 00 eb c6 66 0f 1f 84 00 00 00 00 00 55 48 c7 c7 98 7a 6c a5 c6 05 bc 0d 54 01 01 48 89 e5 e8 a9 84 fb ff <0f> 0b 5d c3 0f 1f 44 00 00 0f 1f 44 00 00 83 7e 60 01 74 0a 48 3b [ 461.137673] RSP: 0018:ffffa77e08cafc68 EFLAGS: 00010082 [ 461.137674] RAX: 0000000000000000 RBX: ffff8b3fc1702d80 RCX: 0000000000000006 [ 461.137674] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff8b3fded164b0 [ 461.137675] RBP: ffffa77e08cafc68 R08: 0000000000000026 R09: 0000000000000339 [ 461.137676] R10: ffff8b3fd060d410 R11: 0000000000000026 R12: ffffffffa4e14e20 [ 461.137677] R13: ffff8b3fdec22940 R14: ffff8b3fc1702da0 R15: ffff8b3fdec22940 [ 461.137678] FS: 00007efe43ee5700(0000) GS:ffff8b3fded00000(0000) knlGS:0000000000000000 [ 461.137679] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 461.137680] CR2: 00007efe30000010 CR3: 0000000301744003 CR4: 00000000001606e0 [ 461.137680] Call Trace: [ 461.137684] push_dl_task.part.46+0x3bc/0x460 [ 461.137686] task_woken_dl+0x60/0x80 [ 461.137689] ttwu_do_wakeup+0x4f/0x150 [ 461.137690] ttwu_do_activate+0x77/0x80 [ 461.137692] try_to_wake_up+0x1d6/0x4c0 [ 461.137693] wake_up_q+0x32/0x70 [ 461.137696] do_futex+0x7e7/0xb50 [ 461.137698] __x64_sys_futex+0x8b/0x180 [ 461.137701] do_syscall_64+0x5a/0x110 [ 461.137703] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 461.137705] RIP: 0033:0x7efe4918ca26 [ 461.137705] Code: 00 00 00 74 17 49 8b 48 20 44 8b 59 10 41 83 e3 30 41 83 fb 20 74 1e be 85 00 00 00 41 ba 01 00 00 00 41 b9 01 00 00 04 0f 05 <48> 3d 01 f0 ff ff 73 1f 31 c0 c3 be 8c 00 00 00 49 89 c8 4d 31 d2 [ 461.137738] RSP: 002b:00007efe43ee4928 EFLAGS: 00000283 ORIG_RAX: 00000000000000ca [ 461.137739] RAX: ffffffffffffffda RBX: 0000000005094df0 RCX: 00007efe4918ca26 [ 461.137740] RDX: 0000000000000001 RSI: 0000000000000085 RDI: 0000000005094e24 [ 461.137741] RBP: 00007efe43ee49c0 R08: 0000000005094e20 R09: 0000000004000001 [ 461.137741] R10: 0000000000000001 R11: 0000000000000283 R12: 0000000000000000 [ 461.137742] R13: 0000000005094df8 R14: 0000000000000001 R15: 0000000000448a10 [ 461.137743] ---[ end trace 187df4cad2bf7649 ]--- This warning happened in the push_dl_task(), because __add_running_bw()->cpufreq_update_util() is getting the rq_clock of the later_rq before its update, which takes place at activate_task(). The fix then is to update the rq_clock before calling add_running_bw(). To avoid double rq_clock_update() call, we set ENQUEUE_NOCLOCK flag to activate_task(). Reported-by: Daniel Casini <[email protected]> Signed-off-by: Daniel Bristot de Oliveira <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Juri Lelli <[email protected]> Cc: Clark Williams <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Luca Abeni <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tommaso Cucinotta <[email protected]> Fixes: e0367b1 sched/deadline: Move CPU frequency selection triggering points Link: http://lkml.kernel.org/r/ca31d073a4788acf0684a8b255f14fea775ccf20.1532077269.git.bristot@redhat.com Signed-off-by: Ingo Molnar <[email protected]>

Kernel panic when with high memory pressure, calltrace looks like, PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java" #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc torvalds#6 [ffff881ec7ed7838] __node_set at ffffffff81680300 torvalds#7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f torvalds#8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5 torvalds#9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8 [exception RIP: _raw_spin_lock_irqsave+47] RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8 RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008 RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098 R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 It happens in the pagefault and results in double pagefault during compacting pages when memory allocation fails. Analysed the vmcore, the page leads to second pagefault is corrupted with _mapcount=-256, but private=0. It's caused by the race between migration and ballooning, and lock missing in virtballoon_migratepage() of virtio_balloon driver. This patch fix the bug. Fixes: e225042 ("virtio_balloon: introduce migration primitives to balloon pages") Cc: [email protected] Signed-off-by: Jiang Biao <[email protected]> Signed-off-by: Huang Chong <[email protected]> Signed-off-by: Michael S. Tsirkin <[email protected]>

Amit Pundir and Youling in parallel reported crashes with recent mainline kernels running Android: F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** F DEBUG : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key F DEBUG : Revision: '0' F DEBUG : ABI: 'arm' F DEBUG : pid: 2261, tid: 2261, name: zygote >>> zygote <<< F DEBUG : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008 ... <snip> ... F DEBUG : backtrace: F DEBUG : #00 pc 00001c04 /system/lib/libc.so (memset+48) F DEBUG : #1 pc 0010c513 /system/lib/libart.so (create_mspace_with_base+82) F DEBUG : #2 pc 0015c601 /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40) F DEBUG : #3 pc 0015c3ed /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string<char, std::__ 1::char_traits<char>, std::__1::allocator<char>> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36) ... This was bisected back to commit bfd40ea ("mm: fix vma_is_anonymous() false-positives"). create_mspace_with_base() in the trace above, utilizes ashmem, and with ashmem, for shared mappings we use shmem_zero_setup(), which sets the vma->vm_ops to &shmem_vm_ops. But for private ashmem mappings nothing sets the vma->vm_ops. Looking at the problematic patch, it seems to add a requirement that one call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be used. Using the dummy_vm_ops seem to triggger SIGBUS when traversing unmapped pages. Thus, this patch adds a call to vma_set_anonymous() for ashmem private mappings and seems to avoid the reported problem. Fixes: bfd40ea ("mm: fix vma_is_anonymous() false-positives") Cc: Kirill Shutemov <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Joel Fernandes <[email protected]> Cc: Colin Cross <[email protected]> Cc: Matthew Wilcox <[email protected]> Reported-by: Amit Pundir <[email protected]> Reported-by: Youling 257 <[email protected]> Signed-off-by: John Stultz <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

…titions" It turns out that commit 721c7fc ("block: fail op_is_write() requests to read-only partitions"), while obviously correct, causes problems for some older lvm2 installations. The reason is that the lvm snapshotting will continue to write to the snapshow COW volume, even after the volume has been marked read-only. End result: snapshot failure. This has actually been fixed in newer version of the lvm2 tool, but the old tools still exist, and the breakage was reported both in the kernel bugzilla and in the Debian bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200439 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=900442 The lvm2 fix is here https://sourceware.org/git/?p=lvm2.git;a=commit;h=a6fdb9d9d70f51c49ad11a87ab4243344e6701a3 but until everybody has updated to recent versions, we'll have to weaken the "never write to read-only partitions" check. It now allows the write to happen, but causes a warning, something like this: generic_make_request: Trying to write to read-only block-device dm-3 (partno X) Modules linked in: nf_tables xt_cgroup xt_owner kvm_intel iwlmvm kvm irqbypass iwlwifi CPU: 1 PID: 77 Comm: kworker/1:1 Not tainted 4.17.9-gentoo #3 Hardware name: LENOVO 20B6A019RT/20B6A019RT, BIOS GJET91WW (2.41 ) 09/21/2016 Workqueue: ksnaphd do_metadata RIP: 0010:generic_make_request_checks+0x4ac/0x600 ... Call Trace: generic_make_request+0x64/0x400 submit_bio+0x6c/0x140 dispatch_io+0x287/0x430 sync_io+0xc3/0x120 dm_io+0x1f8/0x220 do_metadata+0x1d/0x30 process_one_work+0x1b9/0x3e0 worker_thread+0x2b/0x3c0 kthread+0x113/0x130 ret_from_fork+0x35/0x40 Note that this is a "revert" in behavior only. I'm leaving alone the actual code cleanups in commit 721c7fc, but letting the previously uncaught request go through with a warning instead of stopping it. Fixes: 721c7fc ("block: fail op_is_write() requests to read-only partitions") Reported-and-tested-by: WGH <[email protected]> Acked-by: Mike Snitzer <[email protected]> Cc: Sagi Grimberg <[email protected]> Cc: Ilya Dryomov <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Zdenek Kabelac <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

Fix the warning below by calling rhashtable_lookup_fast. Also, make some code movements for better quality and human readability. [ 342.450870] WARNING: suspicious RCU usage [ 342.455856] 4.18.0-rc2+ torvalds#17 Tainted: G O [ 342.462210] ----------------------------- [ 342.467202] ./include/linux/rhashtable.h:481 suspicious rcu_dereference_check() usage! [ 342.476568] [ 342.476568] other info that might help us debug this: [ 342.476568] [ 342.486978] [ 342.486978] rcu_scheduler_active = 2, debug_locks = 1 [ 342.495211] 4 locks held by modprobe/3934: [ 342.500265] #0: 00000000e23116b2 (mlx5_intf_mutex){+.+.}, at: mlx5_unregister_interface+0x18/0x90 [mlx5_core] [ 342.511953] #1: 00000000ca16db96 (rtnl_mutex){+.+.}, at: unregister_netdev+0xe/0x20 [ 342.521109] #2: 00000000a46e2c4b (&priv->state_lock){+.+.}, at: mlx5e_close+0x29/0x60 [mlx5_core] [ 342.531642] #3: 0000000060c5bde3 (mem_id_lock){+.+.}, at: xdp_rxq_info_unreg+0x93/0x6b0 [ 342.541206] [ 342.541206] stack backtrace: [ 342.547075] CPU: 12 PID: 3934 Comm: modprobe Tainted: G O 4.18.0-rc2+ torvalds#17 [ 342.556621] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015 [ 342.565606] Call Trace: [ 342.568861] dump_stack+0x78/0xb3 [ 342.573086] xdp_rxq_info_unreg+0x3f5/0x6b0 [ 342.578285] ? __call_rcu+0x220/0x300 [ 342.582911] mlx5e_free_rq+0x38/0xc0 [mlx5_core] [ 342.588602] mlx5e_close_channel+0x20/0x120 [mlx5_core] [ 342.594976] mlx5e_close_channels+0x26/0x40 [mlx5_core] [ 342.601345] mlx5e_close_locked+0x44/0x50 [mlx5_core] [ 342.607519] mlx5e_close+0x42/0x60 [mlx5_core] [ 342.613005] __dev_close_many+0xb1/0x120 [ 342.617911] dev_close_many+0xa2/0x170 [ 342.622622] rollback_registered_many+0x148/0x460 [ 342.628401] ? __lock_acquire+0x48d/0x11b0 [ 342.633498] ? unregister_netdev+0xe/0x20 [ 342.638495] rollback_registered+0x56/0x90 [ 342.643588] unregister_netdevice_queue+0x7e/0x100 [ 342.649461] unregister_netdev+0x18/0x20 [ 342.654362] mlx5e_remove+0x2a/0x50 [mlx5_core] [ 342.659944] mlx5_remove_device+0xe5/0x110 [mlx5_core] [ 342.666208] mlx5_unregister_interface+0x39/0x90 [mlx5_core] [ 342.673038] cleanup+0x5/0xbfc [mlx5_core] [ 342.678094] __x64_sys_delete_module+0x16b/0x240 [ 342.683725] ? do_syscall_64+0x1c/0x210 [ 342.688476] do_syscall_64+0x5a/0x210 [ 342.693025] entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 8d5d885 ("xdp: rhashtable with allocator ID to pointer mapping") Signed-off-by: Tariq Toukan <[email protected]> Suggested-by: Daniel Borkmann <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Acked-by: Jesper Dangaard Brouer <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>

Currently, whenever a new node is created/re-used from the memhotplug path, we call free_area_init_node()->free_area_init_core(). But there is some code that we do not really need to run when we are coming from such path. free_area_init_core() performs the following actions: 1) Initializes pgdat internals, such as spinlock, waitqueues and more. 2) Account # nr_all_pages and # nr_kernel_pages. These values are used later on when creating hash tables. 3) Account number of managed_pages per zone, substracting dma_reserved and memmap pages. 4) Initializes some fields of the zone structure data 5) Calls init_currently_empty_zone to initialize all the freelists 6) Calls memmap_init to initialize all pages belonging to certain zone When called from memhotplug path, free_area_init_core() only performs actions #1 and #4. Action #2 is pointless as the zones do not have any pages since either the node was freed, or we are re-using it, eitherway all zones belonging to this node should have 0 pages. For the same reason, action #3 results always in manages_pages being 0. Action #5 and torvalds#6 are performed later on when onlining the pages: online_pages()->move_pfn_range_to_zone()->init_currently_empty_zone() online_pages()->move_pfn_range_to_zone()->memmap_init_zone() This patch does two things: First, moves the node/zone initializtion to their own function, so it allows us to create a small version of free_area_init_core, where we only perform: 1) Initialization of pgdat internals, such as spinlock, waitqueues and more 4) Initialization of some fields of the zone structure data These two functions are: pgdat_init_internals() and zone_init_internals(). The second thing this patch does, is to introduce free_area_init_core_hotplug(), the memhotplug version of free_area_init_core(): Currently, we call free_area_init_node() from the memhotplug path. In there, we set some pgdat's fields, and call calculate_node_totalpages(). calculate_node_totalpages() calculates the # of pages the node has. Since the node is either new, or we are re-using it, the zones belonging to this node should not have any pages, so there is no point to calculate this now. Actually, we re-set these values to 0 later on with the calls to: reset_node_managed_pages() reset_node_present_pages() The # of pages per node and the # of pages per zone will be calculated when onlining the pages: online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_zone_range() online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_pgdat_range() Also, since free_area_init_core/free_area_init_node will now only get called during early init, let us replace __paginginit with __init, so their code gets freed up. [[email protected]: fix section usage] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: v6] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Oscar Salvador <[email protected]> Reviewed-by: Pavel Tatashin <[email protected]> Acked-by: Michal Hocko <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Pasha Tatashin <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Dan Williams <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Mel Gorman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

Patch series "add support for relative references in special sections", v10. This adds support for emitting special sections such as initcall arrays, PCI fixups and tracepoints as relative references rather than absolute references. This reduces the size by 50% on 64-bit architectures, but more importantly, it removes the need for carrying relocation metadata for these sections in relocatable kernels (e.g., for KASLR) that needs to be fixed up at boot time. On arm64, this reduces the vmlinux footprint of such a reference by 8x (8 byte absolute reference + 24 byte RELA entry vs 4 byte relative reference) Patch #3 was sent out before as a single patch. This series supersedes the previous submission. This version makes relative ksymtab entries dependent on the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS rather than trying to infer from kbuild test robot replies for which architectures it should be blacklisted. Patch #1 introduces the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS, and sets it for the main architectures that are expected to benefit the most from this feature, i.e., 64-bit architectures or ones that use runtime relocations. Patch #2 add support for #define'ing __DISABLE_EXPORTS to get rid of ksymtab/kcrctab sections in decompressor and EFI stub objects when rebuilding existing C files to run in a different context. Patches #4 - torvalds#6 implement relative references for initcalls, PCI fixups and tracepoints, respectively, all of which produce sections with order ~1000 entries on an arm64 defconfig kernel with tracing enabled. This means we save about 28 KB of vmlinux space for each of these patches. [From the v7 series blurb, which included the jump_label patches as well]: For the arm64 kernel, all patches combined reduce the memory footprint of vmlinux by about 1.3 MB (using a config copied from Ubuntu that has KASLR enabled), of which ~1 MB is the size reduction of the RELA section in .init, and the remaining 300 KB is reduction of .text/.data. This patch (of 6): Before updating certain subsystems to use place relative 32-bit relocations in special sections, to save space and reduce the number of absolute relocations that need to be processed at runtime by relocatable kernels, introduce the Kconfig symbol and define it for some architectures that should be able to support and benefit from it. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ard Biesheuvel <[email protected]> Acked-by: Michael Ellerman <[email protected]> Reviewed-by: Will Deacon <[email protected]> Acked-by: Ingo Molnar <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Kees Cook <[email protected]> Cc: Thomas Garnier <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: "Serge E. Hallyn" <[email protected]> Cc: Bjorn Helgaas <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Russell King <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Petr Mladek <[email protected]> Cc: James Morris <[email protected]> Cc: Nicolas Pitre <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Sergey Senozhatsky <[email protected]>, Cc: James Morris <[email protected]> Cc: Jessica Yu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

This patch fixes the race between netvsc_probe() and rndis_set_subchannel(), which can cause a deadlock. These are the related 3 paths which show the deadlock: path #1: Workqueue: hv_vmbus_con vmbus_onmessage_work [hv_vmbus] Call Trace: schedule schedule_preempt_disabled __mutex_lock __device_attach bus_probe_device device_add vmbus_device_register vmbus_onoffer vmbus_onmessage_work process_one_work worker_thread kthread ret_from_fork path #2: schedule schedule_preempt_disabled __mutex_lock netvsc_probe vmbus_probe really_probe __driver_attach bus_for_each_dev driver_attach_async async_run_entry_fn process_one_work worker_thread kthread ret_from_fork path #3: Workqueue: events netvsc_subchan_work [hv_netvsc] Call Trace: schedule rndis_set_subchannel netvsc_subchan_work process_one_work worker_thread kthread ret_from_fork Before path #1 finishes, path #2 can start to run, because just before the "bus_probe_device(dev);" in device_add() in path #1, there is a line "object_uevent(&dev->kobj, KOBJ_ADD);", so systemd-udevd can immediately try to load hv_netvsc and hence path #2 can start to run. Next, path #2 offloads the subchannal's initialization to a workqueue, i.e. path #3, so we can end up in a deadlock situation like this: Path #2 gets the device lock, and is trying to get the rtnl lock; Path #3 gets the rtnl lock and is waiting for all the subchannel messages to be processed; Path #1 is trying to get the device lock, but since #2 is not releasing the device lock, path #1 has to sleep; since the VMBus messages are processed one by one, this means the sub-channel messages can't be procedded, so #3 has to sleep with the rtnl lock held, and finally #2 has to sleep... Now all the 3 paths are sleeping and we hit the deadlock. With the patch, we can make sure #2 gets both the device lock and the rtnl lock together, gets its job done, and releases the locks, so #1 and #3 will not be blocked for ever. Fixes: 8195b13 ("hv_netvsc: fix deadlock on hotplug") Signed-off-by: Dexuan Cui <[email protected]> Cc: Stephen Hemminger <[email protected]> Cc: K. Y. Srinivasan <[email protected]> Cc: Haiyang Zhang <[email protected]> Signed-off-by: David S. Miller <[email protected]>

…equests Currently, nouveau uses the generic drm_fb_helper_output_poll_changed() function provided by DRM as it's output_poll_changed callback. Unfortunately however, this function doesn't grab runtime PM references early enough and even if it did-we can't block waiting for the device to resume in output_poll_changed() since it's very likely that we'll need to grab the fb_helper lock at some point during the runtime resume process. This currently results in deadlocking like so: [ 246.669625] INFO: task kworker/4:0:37 blocked for more than 120 seconds. [ 246.673398] Not tainted 4.18.0-rc5Lyude-Test+ #2 [ 246.675271] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 246.676527] kworker/4:0 D 0 37 2 0x80000000 [ 246.677580] Workqueue: events output_poll_execute [drm_kms_helper] [ 246.678704] Call Trace: [ 246.679753] __schedule+0x322/0xaf0 [ 246.680916] schedule+0x33/0x90 [ 246.681924] schedule_preempt_disabled+0x15/0x20 [ 246.683023] __mutex_lock+0x569/0x9a0 [ 246.684035] ? kobject_uevent_env+0x117/0x7b0 [ 246.685132] ? drm_fb_helper_hotplug_event.part.28+0x20/0xb0 [drm_kms_helper] [ 246.686179] mutex_lock_nested+0x1b/0x20 [ 246.687278] ? mutex_lock_nested+0x1b/0x20 [ 246.688307] drm_fb_helper_hotplug_event.part.28+0x20/0xb0 [drm_kms_helper] [ 246.689420] drm_fb_helper_output_poll_changed+0x23/0x30 [drm_kms_helper] [ 246.690462] drm_kms_helper_hotplug_event+0x2a/0x30 [drm_kms_helper] [ 246.691570] output_poll_execute+0x198/0x1c0 [drm_kms_helper] [ 246.692611] process_one_work+0x231/0x620 [ 246.693725] worker_thread+0x214/0x3a0 [ 246.694756] kthread+0x12b/0x150 [ 246.695856] ? wq_pool_ids_show+0x140/0x140 [ 246.696888] ? kthread_create_worker_on_cpu+0x70/0x70 [ 246.697998] ret_from_fork+0x3a/0x50 [ 246.699034] INFO: task kworker/0:1:60 blocked for more than 120 seconds. [ 246.700153] Not tainted 4.18.0-rc5Lyude-Test+ #2 [ 246.701182] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 246.702278] kworker/0:1 D 0 60 2 0x80000000 [ 246.703293] Workqueue: pm pm_runtime_work [ 246.704393] Call Trace: [ 246.705403] __schedule+0x322/0xaf0 [ 246.706439] ? wait_for_completion+0x104/0x190 [ 246.707393] schedule+0x33/0x90 [ 246.708375] schedule_timeout+0x3a5/0x590 [ 246.709289] ? mark_held_locks+0x58/0x80 [ 246.710208] ? _raw_spin_unlock_irq+0x2c/0x40 [ 246.711222] ? wait_for_completion+0x104/0x190 [ 246.712134] ? trace_hardirqs_on_caller+0xf4/0x190 [ 246.713094] ? wait_for_completion+0x104/0x190 [ 246.713964] wait_for_completion+0x12c/0x190 [ 246.714895] ? wake_up_q+0x80/0x80 [ 246.715727] ? get_work_pool+0x90/0x90 [ 246.716649] flush_work+0x1c9/0x280 [ 246.717483] ? flush_workqueue_prep_pwqs+0x1b0/0x1b0 [ 246.718442] __cancel_work_timer+0x146/0x1d0 [ 246.719247] cancel_delayed_work_sync+0x13/0x20 [ 246.720043] drm_kms_helper_poll_disable+0x1f/0x30 [drm_kms_helper] [ 246.721123] nouveau_pmops_runtime_suspend+0x3d/0xb0 [nouveau] [ 246.721897] pci_pm_runtime_suspend+0x6b/0x190 [ 246.722825] ? pci_has_legacy_pm_support+0x70/0x70 [ 246.723737] __rpm_callback+0x7a/0x1d0 [ 246.724721] ? pci_has_legacy_pm_support+0x70/0x70 [ 246.725607] rpm_callback+0x24/0x80 [ 246.726553] ? pci_has_legacy_pm_support+0x70/0x70 [ 246.727376] rpm_suspend+0x142/0x6b0 [ 246.728185] pm_runtime_work+0x97/0xc0 [ 246.728938] process_one_work+0x231/0x620 [ 246.729796] worker_thread+0x44/0x3a0 [ 246.730614] kthread+0x12b/0x150 [ 246.731395] ? wq_pool_ids_show+0x140/0x140 [ 246.732202] ? kthread_create_worker_on_cpu+0x70/0x70 [ 246.732878] ret_from_fork+0x3a/0x50 [ 246.733768] INFO: task kworker/4:2:422 blocked for more than 120 seconds. [ 246.734587] Not tainted 4.18.0-rc5Lyude-Test+ #2 [ 246.735393] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 246.736113] kworker/4:2 D 0 422 2 0x80000080 [ 246.736789] Workqueue: events_long drm_dp_mst_link_probe_work [drm_kms_helper] [ 246.737665] Call Trace: [ 246.738490] __schedule+0x322/0xaf0 [ 246.739250] schedule+0x33/0x90 [ 246.739908] rpm_resume+0x19c/0x850 [ 246.740750] ? finish_wait+0x90/0x90 [ 246.741541] __pm_runtime_resume+0x4e/0x90 [ 246.742370] nv50_disp_atomic_commit+0x31/0x210 [nouveau] [ 246.743124] drm_atomic_commit+0x4a/0x50 [drm] [ 246.743775] restore_fbdev_mode_atomic+0x1c8/0x240 [drm_kms_helper] [ 246.744603] restore_fbdev_mode+0x31/0x140 [drm_kms_helper] [ 246.745373] drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xb0 [drm_kms_helper] [ 246.746220] drm_fb_helper_set_par+0x2d/0x50 [drm_kms_helper] [ 246.746884] drm_fb_helper_hotplug_event.part.28+0x96/0xb0 [drm_kms_helper] [ 246.747675] drm_fb_helper_output_poll_changed+0x23/0x30 [drm_kms_helper] [ 246.748544] drm_kms_helper_hotplug_event+0x2a/0x30 [drm_kms_helper] [ 246.749439] nv50_mstm_hotplug+0x15/0x20 [nouveau] [ 246.750111] drm_dp_send_link_address+0x177/0x1c0 [drm_kms_helper] [ 246.750764] drm_dp_check_and_send_link_address+0xa8/0xd0 [drm_kms_helper] [ 246.751602] drm_dp_mst_link_probe_work+0x51/0x90 [drm_kms_helper] [ 246.752314] process_one_work+0x231/0x620 [ 246.752979] worker_thread+0x44/0x3a0 [ 246.753838] kthread+0x12b/0x150 [ 246.754619] ? wq_pool_ids_show+0x140/0x140 [ 246.755386] ? kthread_create_worker_on_cpu+0x70/0x70 [ 246.756162] ret_from_fork+0x3a/0x50 [ 246.756847] Showing all locks held in the system: [ 246.758261] 3 locks held by kworker/4:0/37: [ 246.759016] #0: 00000000f8df4d2d ((wq_completion)"events"){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.759856] #1: 00000000e6065461 ((work_completion)(&(&dev->mode_config.output_poll_work)->work)){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.760670] #2: 00000000cb66735f (&helper->lock){+.+.}, at: drm_fb_helper_hotplug_event.part.28+0x20/0xb0 [drm_kms_helper] [ 246.761516] 2 locks held by kworker/0:1/60: [ 246.762274] #0: 00000000fff6be0f ((wq_completion)"pm"){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.762982] #1: 000000005ab44fb4 ((work_completion)(&dev->power.work)){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.763890] 1 lock held by khungtaskd/64: [ 246.764664] #0: 000000008cb8b5c3 (rcu_read_lock){....}, at: debug_show_all_locks+0x23/0x185 [ 246.765588] 5 locks held by kworker/4:2/422: [ 246.766440] #0: 00000000232f0959 ((wq_completion)"events_long"){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.767390] #1: 00000000bb59b134 ((work_completion)(&mgr->work)){+.+.}, at: process_one_work+0x1b3/0x620 [ 246.768154] #2: 00000000cb66735f (&helper->lock){+.+.}, at: drm_fb_helper_restore_fbdev_mode_unlocked+0x4c/0xb0 [drm_kms_helper] [ 246.768966] #3: 000000004c8f0b6b (crtc_ww_class_acquire){+.+.}, at: restore_fbdev_mode_atomic+0x4b/0x240 [drm_kms_helper] [ 246.769921] #4: 000000004c34a296 (crtc_ww_class_mutex){+.+.}, at: drm_modeset_backoff+0x8a/0x1b0 [drm] [ 246.770839] 1 lock held by dmesg/1038: [ 246.771739] 2 locks held by zsh/1172: [ 246.772650] #0: 00000000836d0438 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 246.773680] #1: 000000001f4f4d48 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0xc1/0x870 [ 246.775522] ============================================= After trying dozens of different solutions, I found one very simple one that should also have the benefit of preventing us from having to fight locking for the rest of our lives. So, we work around these deadlocks by deferring all fbcon hotplug events that happen after the runtime suspend process starts until after the device is resumed again. Changes since v7: - Fixup commit message - Daniel Vetter Changes since v6: - Remove unused nouveau_fbcon_hotplugged_in_suspend() - Ilia Changes since v5: - Come up with the (hopefully final) solution for solving this dumb problem, one that is a lot less likely to cause issues with locking in the future. This should work around all deadlock conditions with fbcon brought up thus far. Changes since v4: - Add nouveau_fbcon_hotplugged_in_suspend() to workaround deadlock condition that Lukas described - Just move all of this out of drm_fb_helper. It seems that other DRM drivers have already figured out other workarounds for this. If other drivers do end up needing this in the future, we can just move this back into drm_fb_helper again. Changes since v3: - Actually check if fb_helper is NULL in both new helpers - Actually check drm_fbdev_emulation in both new helpers - Don't fire off a fb_helper hotplug unconditionally; only do it if the following conditions are true (as otherwise, calling this in the wrong spot will cause Bad Things to happen): - fb_helper hotplug handling was actually inhibited previously - fb_helper actually has a delayed hotplug pending - fb_helper is actually bound - fb_helper is actually initialized - Add __must_check to drm_fb_helper_suspend_hotplug(). There's no situation where a driver would actually want to use this without checking the return value, so enforce that - Rewrite and clarify the documentation for both helpers. - Make sure to return true in the drm_fb_helper_suspend_hotplug() stub that's provided in drm_fb_helper.h when CONFIG_DRM_FBDEV_EMULATION isn't enabled - Actually grab the toplevel fb_helper lock in drm_fb_helper_resume_hotplug(), since it's possible other activity (such as a hotplug) could be going on at the same time the driver calls drm_fb_helper_resume_hotplug(). We need this to check whether or not drm_fb_helper_hotplug_event() needs to be called anyway Signed-off-by: Lyude Paul <[email protected]> Reviewed-by: Karol Herbst <[email protected]> Acked-by: Daniel Vetter <[email protected]> Cc: [email protected] Cc: Lukas Wunner <[email protected]> Signed-off-by: Ben Skeggs <[email protected]>

When we disable hotplugging on the GPU, we need to be able to synchronize with each connector's hotplug interrupt handler before the interrupt is finally disabled. This can be a problem however, since nouveau_connector_detect() currently grabs a runtime power reference when handling connector probing. This will deadlock the runtime suspend handler like so: [ 861.480896] INFO: task kworker/0:2:61 blocked for more than 120 seconds. [ 861.483290] Tainted: G O 4.18.0-rc6Lyude-Test+ #1 [ 861.485158] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 861.486332] kworker/0:2 D 0 61 2 0x80000000 [ 861.487044] Workqueue: events nouveau_display_hpd_work [nouveau] [ 861.487737] Call Trace: [ 861.488394] __schedule+0x322/0xaf0 [ 861.489070] schedule+0x33/0x90 [ 861.489744] rpm_resume+0x19c/0x850 [ 861.490392] ? finish_wait+0x90/0x90 [ 861.491068] __pm_runtime_resume+0x4e/0x90 [ 861.491753] nouveau_display_hpd_work+0x22/0x60 [nouveau] [ 861.492416] process_one_work+0x231/0x620 [ 861.493068] worker_thread+0x44/0x3a0 [ 861.493722] kthread+0x12b/0x150 [ 861.494342] ? wq_pool_ids_show+0x140/0x140 [ 861.494991] ? kthread_create_worker_on_cpu+0x70/0x70 [ 861.495648] ret_from_fork+0x3a/0x50 [ 861.496304] INFO: task kworker/6:2:320 blocked for more than 120 seconds. [ 861.496968] Tainted: G O 4.18.0-rc6Lyude-Test+ #1 [ 861.497654] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 861.498341] kworker/6:2 D 0 320 2 0x80000080 [ 861.499045] Workqueue: pm pm_runtime_work [ 861.499739] Call Trace: [ 861.500428] __schedule+0x322/0xaf0 [ 861.501134] ? wait_for_completion+0x104/0x190 [ 861.501851] schedule+0x33/0x90 [ 861.502564] schedule_timeout+0x3a5/0x590 [ 861.503284] ? mark_held_locks+0x58/0x80 [ 861.503988] ? _raw_spin_unlock_irq+0x2c/0x40 [ 861.504710] ? wait_for_completion+0x104/0x190 [ 861.505417] ? trace_hardirqs_on_caller+0xf4/0x190 [ 861.506136] ? wait_for_completion+0x104/0x190 [ 861.506845] wait_for_completion+0x12c/0x190 [ 861.507555] ? wake_up_q+0x80/0x80 [ 861.508268] flush_work+0x1c9/0x280 [ 861.508990] ? flush_workqueue_prep_pwqs+0x1b0/0x1b0 [ 861.509735] nvif_notify_put+0xb1/0xc0 [nouveau] [ 861.510482] nouveau_display_fini+0xbd/0x170 [nouveau] [ 861.511241] nouveau_display_suspend+0x67/0x120 [nouveau] [ 861.511969] nouveau_do_suspend+0x5e/0x2d0 [nouveau] [ 861.512715] nouveau_pmops_runtime_suspend+0x47/0xb0 [nouveau] [ 861.513435] pci_pm_runtime_suspend+0x6b/0x180 [ 861.514165] ? pci_has_legacy_pm_support+0x70/0x70 [ 861.514897] __rpm_callback+0x7a/0x1d0 [ 861.515618] ? pci_has_legacy_pm_support+0x70/0x70 [ 861.516313] rpm_callback+0x24/0x80 [ 861.517027] ? pci_has_legacy_pm_support+0x70/0x70 [ 861.517741] rpm_suspend+0x142/0x6b0 [ 861.518449] pm_runtime_work+0x97/0xc0 [ 861.519144] process_one_work+0x231/0x620 [ 861.519831] worker_thread+0x44/0x3a0 [ 861.520522] kthread+0x12b/0x150 [ 861.521220] ? wq_pool_ids_show+0x140/0x140 [ 861.521925] ? kthread_create_worker_on_cpu+0x70/0x70 [ 861.522622] ret_from_fork+0x3a/0x50 [ 861.523299] INFO: task kworker/6:0:1329 blocked for more than 120 seconds. [ 861.523977] Tainted: G O 4.18.0-rc6Lyude-Test+ #1 [ 861.524644] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 861.525349] kworker/6:0 D 0 1329 2 0x80000000 [ 861.526073] Workqueue: events nvif_notify_work [nouveau] [ 861.526751] Call Trace: [ 861.527411] __schedule+0x322/0xaf0 [ 861.528089] schedule+0x33/0x90 [ 861.528758] rpm_resume+0x19c/0x850 [ 861.529399] ? finish_wait+0x90/0x90 [ 861.530073] __pm_runtime_resume+0x4e/0x90 [ 861.530798] nouveau_connector_detect+0x7e/0x510 [nouveau] [ 861.531459] ? ww_mutex_lock+0x47/0x80 [ 861.532097] ? ww_mutex_lock+0x47/0x80 [ 861.532819] ? drm_modeset_lock+0x88/0x130 [drm] [ 861.533481] drm_helper_probe_detect_ctx+0xa0/0x100 [drm_kms_helper] [ 861.534127] drm_helper_hpd_irq_event+0xa4/0x120 [drm_kms_helper] [ 861.534940] nouveau_connector_hotplug+0x98/0x120 [nouveau] [ 861.535556] nvif_notify_work+0x2d/0xb0 [nouveau] [ 861.536221] process_one_work+0x231/0x620 [ 861.536994] worker_thread+0x44/0x3a0 [ 861.537757] kthread+0x12b/0x150 [ 861.538463] ? wq_pool_ids_show+0x140/0x140 [ 861.539102] ? kthread_create_worker_on_cpu+0x70/0x70 [ 861.539815] ret_from_fork+0x3a/0x50 [ 861.540521] Showing all locks held in the system: [ 861.541696] 2 locks held by kworker/0:2/61: [ 861.542406] #0: 000000002dbf8af5 ((wq_completion)"events"){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.543071] #1: 0000000076868126 ((work_completion)(&drm->hpd_work)){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.543814] 1 lock held by khungtaskd/64: [ 861.544535] #0: 0000000059db4b53 (rcu_read_lock){....}, at: debug_show_all_locks+0x23/0x185 [ 861.545160] 3 locks held by kworker/6:2/320: [ 861.545896] #0: 00000000d9e1bc59 ((wq_completion)"pm"){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.546702] #1: 00000000c9f92d84 ((work_completion)(&dev->power.work)){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.547443] #2: 000000004afc5de1 (drm_connector_list_iter){.+.+}, at: nouveau_display_fini+0x96/0x170 [nouveau] [ 861.548146] 1 lock held by dmesg/983: [ 861.548889] 2 locks held by zsh/1250: [ 861.549605] #0: 00000000348e3cf6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 [ 861.550393] #1: 000000007009a7a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0xc1/0x870 [ 861.551122] 6 locks held by kworker/6:0/1329: [ 861.551957] #0: 000000002dbf8af5 ((wq_completion)"events"){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.552765] #1: 00000000ddb499ad ((work_completion)(&notify->work)#2){+.+.}, at: process_one_work+0x1b3/0x620 [ 861.553582] #2: 000000006e013cbe (&dev->mode_config.mutex){+.+.}, at: drm_helper_hpd_irq_event+0x6c/0x120 [drm_kms_helper] [ 861.554357] #3: 000000004afc5de1 (drm_connector_list_iter){.+.+}, at: drm_helper_hpd_irq_event+0x78/0x120 [drm_kms_helper] [ 861.555227] #4: 0000000044f294d9 (crtc_ww_class_acquire){+.+.}, at: drm_helper_probe_detect_ctx+0x3d/0x100 [drm_kms_helper] [ 861.556133] #5: 00000000db193642 (crtc_ww_class_mutex){+.+.}, at: drm_modeset_lock+0x4b/0x130 [drm] [ 861.557864] ============================================= [ 861.559507] NMI backtrace for cpu 2 [ 861.560363] CPU: 2 PID: 64 Comm: khungtaskd Tainted: G O 4.18.0-rc6Lyude-Test+ #1 [ 861.561197] Hardware name: LENOVO 20EQS64N0B/20EQS64N0B, BIOS N1EET78W (1.51 ) 05/18/2018 [ 861.561948] Call Trace: [ 861.562757] dump_stack+0x8e/0xd3 [ 861.563516] nmi_cpu_backtrace.cold.3+0x14/0x5a [ 861.564269] ? lapic_can_unplug_cpu.cold.27+0x42/0x42 [ 861.565029] nmi_trigger_cpumask_backtrace+0xa1/0xae [ 861.565789] arch_trigger_cpumask_backtrace+0x19/0x20 [ 861.566558] watchdog+0x316/0x580 [ 861.567355] kthread+0x12b/0x150 [ 861.568114] ? reset_hung_task_detector+0x20/0x20 [ 861.568863] ? kthread_create_worker_on_cpu+0x70/0x70 [ 861.569598] ret_from_fork+0x3a/0x50 [ 861.570370] Sending NMI from CPU 2 to CPUs 0-1,3-7: [ 861.571426] NMI backtrace for cpu 6 skipped: idling at intel_idle+0x7f/0x120 [ 861.571429] NMI backtrace for cpu 7 skipped: idling at intel_idle+0x7f/0x120 [ 861.571432] NMI backtrace for cpu 3 skipped: idling at intel_idle+0x7f/0x120 [ 861.571464] NMI backtrace for cpu 5 skipped: idling at intel_idle+0x7f/0x120 [ 861.571467] NMI backtrace for cpu 0 skipped: idling at intel_idle+0x7f/0x120 [ 861.571469] NMI backtrace for cpu 4 skipped: idling at intel_idle+0x7f/0x120 [ 861.571472] NMI backtrace for cpu 1 skipped: idling at intel_idle+0x7f/0x120 [ 861.572428] Kernel panic - not syncing: hung_task: blocked tasks So: fix this by making it so that normal hotplug handling /only/ happens so long as the GPU is currently awake without any pending runtime PM requests. In the event that a hotplug occurs while the device is suspending or resuming, we can simply defer our response until the GPU is fully runtime resumed again. Changes since v4: - Use a new trick I came up with using pm_runtime_get() instead of the hackish junk we had before Signed-off-by: Lyude Paul <[email protected]> Reviewed-by: Karol Herbst <[email protected]> Acked-by: Daniel Vetter <[email protected]> Cc: [email protected] Cc: Lukas Wunner <[email protected]> Signed-off-by: Ben Skeggs <[email protected]>

A kernel crash occurrs when defragmented packet is fragmented in ip_do_fragment(). In defragment routine, skb_orphan() is called and skb->ip_defrag_offset is set. but skb->sk and skb->ip_defrag_offset are same union member. so that frag->sk is not NULL. Hence crash occurrs in skb->sk check routine in ip_do_fragment() when defragmented packet is fragmented. test commands: %iptables -t nat -I POSTROUTING -j MASQUERADE %hping3 192.168.4.2 -s 1000 -p 2000 -d 60000 splat looks like: [ 261.069429] kernel BUG at net/ipv4/ip_output.c:636! [ 261.075753] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 261.083854] CPU: 1 PID: 1349 Comm: hping3 Not tainted 4.19.0-rc2+ #3 [ 261.100977] RIP: 0010:ip_do_fragment+0x1613/0x2600 [ 261.106945] Code: e8 e2 38 e3 fe 4c 8b 44 24 18 48 8b 74 24 08 e9 92 f6 ff ff 80 3c 02 00 0f 85 da 07 00 00 48 8b b5 d0 00 00 00 e9 25 f6 ff ff <0f> 0b 0f 0b 44 8b 54 24 58 4c 8b 4c 24 18 4c 8b 5c 24 60 4c 8b 6c [ 261.127015] RSP: 0018:ffff8801031cf2c0 EFLAGS: 00010202 [ 261.134156] RAX: 1ffff1002297537b RBX: ffffed0020639e6e RCX: 0000000000000004 [ 261.142156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880114ba9bd8 [ 261.150157] RBP: ffff880114ba8a40 R08: ffffed0022975395 R09: ffffed0022975395 [ 261.158157] R10: 0000000000000001 R11: ffffed0022975394 R12: ffff880114ba9ca4 [ 261.166159] R13: 0000000000000010 R14: ffff880114ba9bc0 R15: dffffc0000000000 [ 261.174169] FS: 00007fbae2199700(0000) GS:ffff88011b400000(0000) knlGS:0000000000000000 [ 261.183012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 261.189013] CR2: 00005579244fe000 CR3: 0000000119bf4000 CR4: 00000000001006e0 [ 261.198158] Call Trace: [ 261.199018] ? dst_output+0x180/0x180 [ 261.205011] ? save_trace+0x300/0x300 [ 261.209018] ? ip_copy_metadata+0xb00/0xb00 [ 261.213034] ? sched_clock_local+0xd4/0x140 [ 261.218158] ? kill_l4proto+0x120/0x120 [nf_conntrack] [ 261.223014] ? rt_cpu_seq_stop+0x10/0x10 [ 261.227014] ? find_held_lock+0x39/0x1c0 [ 261.233008] ip_finish_output+0x51d/0xb50 [ 261.237006] ? ip_fragment.constprop.56+0x220/0x220 [ 261.243011] ? nf_ct_l4proto_register_one+0x5b0/0x5b0 [nf_conntrack] [ 261.250152] ? rcu_is_watching+0x77/0x120 [ 261.255010] ? nf_nat_ipv4_out+0x1e/0x2b0 [nf_nat_ipv4] [ 261.261033] ? nf_hook_slow+0xb1/0x160 [ 261.265007] ip_output+0x1c7/0x710 [ 261.269005] ? ip_mc_output+0x13f0/0x13f0 [ 261.273002] ? __local_bh_enable_ip+0xe9/0x1b0 [ 261.278152] ? ip_fragment.constprop.56+0x220/0x220 [ 261.282996] ? nf_hook_slow+0xb1/0x160 [ 261.287007] raw_sendmsg+0x21f9/0x4420 [ 261.291008] ? dst_output+0x180/0x180 [ 261.297003] ? sched_clock_cpu+0x126/0x170 [ 261.301003] ? find_held_lock+0x39/0x1c0 [ 261.306155] ? stop_critical_timings+0x420/0x420 [ 261.311004] ? check_flags.part.36+0x450/0x450 [ 261.315005] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.320995] ? _raw_spin_unlock_irq+0x29/0x40 [ 261.326142] ? cyc2ns_read_end+0x10/0x10 [ 261.330139] ? raw_bind+0x280/0x280 [ 261.334138] ? sched_clock_cpu+0x126/0x170 [ 261.338995] ? check_flags.part.36+0x450/0x450 [ 261.342991] ? __lock_acquire+0x4500/0x4500 [ 261.348994] ? inet_sendmsg+0x11c/0x500 [ 261.352989] ? dst_output+0x180/0x180 [ 261.357012] inet_sendmsg+0x11c/0x500 [ ... ] v2: - clear skb->sk at reassembly routine.(Eric Dumarzet) Fixes: fa0f527 ("ip: use rb trees for IP frag queue.") Suggested-by: Eric Dumazet <[email protected]> Signed-off-by: Taehee Yoo <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]>

The following lockdep report can be triggered by writing to /sys/kernel/debug/sched_features: ====================================================== WARNING: possible circular locking dependency detected 4.18.0-rc6-00152-gcd3f77d74ac3-dirty torvalds#18 Not tainted ------------------------------------------------------ sh/3358 is trying to acquire lock: 000000004ad3989d (cpu_hotplug_lock.rw_sem){++++}, at: static_key_enable+0x14/0x30 but task is already holding lock: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&sb->s_type->i_mutex_key#3){+.+.}: lock_acquire+0xb8/0x148 down_write+0xac/0x140 start_creating+0x5c/0x168 debugfs_create_dir+0x18/0x220 opp_debug_register+0x8c/0x120 _add_opp_dev+0x104/0x1f8 dev_pm_opp_get_opp_table+0x174/0x340 _of_add_opp_table_v2+0x110/0x760 dev_pm_opp_of_add_table+0x5c/0x240 dev_pm_opp_of_cpumask_add_table+0x5c/0x100 cpufreq_init+0x160/0x430 cpufreq_online+0x1cc/0xe30 cpufreq_add_dev+0x78/0x198 subsys_interface_register+0x168/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #2 (opp_table_lock){+.+.}: lock_acquire+0xb8/0x148 __mutex_lock+0x104/0xf50 mutex_lock_nested+0x1c/0x28 _of_add_opp_table_v2+0xb4/0x760 dev_pm_opp_of_add_table+0x5c/0x240 dev_pm_opp_of_cpumask_add_table+0x5c/0x100 cpufreq_init+0x160/0x430 cpufreq_online+0x1cc/0xe30 cpufreq_add_dev+0x78/0x198 subsys_interface_register+0x168/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #1 (subsys mutex#6){+.+.}: lock_acquire+0xb8/0x148 __mutex_lock+0x104/0xf50 mutex_lock_nested+0x1c/0x28 subsys_interface_register+0xd8/0x270 cpufreq_register_driver+0x1c8/0x278 dt_cpufreq_probe+0xdc/0x1b8 platform_drv_probe+0xb4/0x168 driver_probe_device+0x318/0x4b0 __device_attach_driver+0xfc/0x1f0 bus_for_each_drv+0xf8/0x180 __device_attach+0x164/0x200 device_initial_probe+0x10/0x18 bus_probe_device+0x110/0x178 device_add+0x6d8/0x908 platform_device_add+0x138/0x3d8 platform_device_register_full+0x1cc/0x1f8 cpufreq_dt_platdev_init+0x174/0x1bc do_one_initcall+0xb8/0x310 kernel_init_freeable+0x4b8/0x56c kernel_init+0x10/0x138 ret_from_fork+0x10/0x18 -> #0 (cpu_hotplug_lock.rw_sem){++++}: __lock_acquire+0x203c/0x21d0 lock_acquire+0xb8/0x148 cpus_read_lock+0x58/0x1c8 static_key_enable+0x14/0x30 sched_feat_write+0x314/0x428 full_proxy_write+0xa0/0x138 __vfs_write+0xd8/0x388 vfs_write+0xdc/0x318 ksys_write+0xb4/0x138 sys_write+0xc/0x18 __sys_trace_return+0x0/0x4 other info that might help us debug this: Chain exists of: cpu_hotplug_lock.rw_sem --> opp_table_lock --> &sb->s_type->i_mutex_key#3 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#3); lock(opp_table_lock); lock(&sb->s_type->i_mutex_key#3); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** 2 locks held by sh/3358: #0: 00000000a8c4b363 (sb_writers#10){.+.+}, at: vfs_write+0x238/0x318 #1: 00000000c1b31a88 (&sb->s_type->i_mutex_key#3){+.+.}, at: sched_feat_write+0x160/0x428 stack backtrace: CPU: 5 PID: 3358 Comm: sh Not tainted 4.18.0-rc6-00152-gcd3f77d74ac3-dirty torvalds#18 Hardware name: Renesas H3ULCB Kingfisher board based on r8a7795 ES2.0+ (DT) Call trace: dump_backtrace+0x0/0x288 show_stack+0x14/0x20 dump_stack+0x13c/0x1ac print_circular_bug.isra.10+0x270/0x438 check_prev_add.constprop.16+0x4dc/0xb98 __lock_acquire+0x203c/0x21d0 lock_acquire+0xb8/0x148 cpus_read_lock+0x58/0x1c8 static_key_enable+0x14/0x30 sched_feat_write+0x314/0x428 full_proxy_write+0xa0/0x138 __vfs_write+0xd8/0x388 vfs_write+0xdc/0x318 ksys_write+0xb4/0x138 sys_write+0xc/0x18 __sys_trace_return+0x0/0x4 This is because when loading the cpufreq_dt module we first acquire cpu_hotplug_lock.rw_sem lock, then in cpufreq_init(), we are taking the &sb->s_type->i_mutex_key lock. But when writing to /sys/kernel/debug/sched_features, the cpu_hotplug_lock.rw_sem lock depends on the &sb->s_type->i_mutex_key lock. To fix this bug, reverse the lock acquisition order when writing to sched_features, this way cpu_hotplug_lock.rw_sem no longer depends on &sb->s_type->i_mutex_key. Tested-by: Dietmar Eggemann <[email protected]> Signed-off-by: Jiada Wang <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Eugeniu Rosca <[email protected]> Cc: George G. Davis <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>

When netvsc device is removed it can call reschedule in RCU context. This happens because canceling the subchannel setup work could (in theory) cause a reschedule when manipulating the timer. To reproduce, run with lockdep enabled kernel and unbind a network device from hv_netvsc (via sysfs). [ 160.682011] WARNING: suspicious RCU usage [ 160.707466] 4.19.0-rc3-uio+ #2 Not tainted [ 160.709937] ----------------------------- [ 160.712352] ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section! [ 160.723691] [ 160.723691] other info that might help us debug this: [ 160.723691] [ 160.730955] [ 160.730955] rcu_scheduler_active = 2, debug_locks = 1 [ 160.762813] 5 locks held by rebind-eth.sh/1812: [ 160.766851] #0: 000000008befa37a (sb_writers#6){.+.+}, at: vfs_write+0x184/0x1b0 [ 160.773416] #1: 00000000b097f236 (&of->mutex){+.+.}, at: kernfs_fop_write+0xe2/0x1a0 [ 160.783766] #2: 0000000041ee6889 (kn->count#3){++++}, at: kernfs_fop_write+0xeb/0x1a0 [ 160.787465] #3: 0000000056d92a74 (&dev->mutex){....}, at: device_release_driver_internal+0x39/0x250 [ 160.816987] #4: 0000000030f6031e (rcu_read_lock){....}, at: netvsc_remove+0x1e/0x250 [hv_netvsc] [ 160.828629] [ 160.828629] stack backtrace: [ 160.831966] CPU: 1 PID: 1812 Comm: rebind-eth.sh Not tainted 4.19.0-rc3-uio+ #2 [ 160.832952] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012 [ 160.832952] Call Trace: [ 160.832952] dump_stack+0x85/0xcb [ 160.832952] ___might_sleep+0x1a3/0x240 [ 160.832952] __flush_work+0x57/0x2e0 [ 160.832952] ? __mutex_lock+0x83/0x990 [ 160.832952] ? __kernfs_remove+0x24f/0x2e0 [ 160.832952] ? __kernfs_remove+0x1b2/0x2e0 [ 160.832952] ? mark_held_locks+0x50/0x80 [ 160.832952] ? get_work_pool+0x90/0x90 [ 160.832952] __cancel_work_timer+0x13c/0x1e0 [ 160.832952] ? netvsc_remove+0x1e/0x250 [hv_netvsc] [ 160.832952] ? __lock_is_held+0x55/0x90 [ 160.832952] netvsc_remove+0x9a/0x250 [hv_netvsc] [ 160.832952] vmbus_remove+0x26/0x30 [ 160.832952] device_release_driver_internal+0x18a/0x250 [ 160.832952] unbind_store+0xb4/0x180 [ 160.832952] kernfs_fop_write+0x113/0x1a0 [ 160.832952] __vfs_write+0x36/0x1a0 [ 160.832952] ? rcu_read_lock_sched_held+0x6b/0x80 [ 160.832952] ? rcu_sync_lockdep_assert+0x2e/0x60 [ 160.832952] ? __sb_start_write+0x141/0x1a0 [ 160.832952] ? vfs_write+0x184/0x1b0 [ 160.832952] vfs_write+0xbe/0x1b0 [ 160.832952] ksys_write+0x55/0xc0 [ 160.832952] do_syscall_64+0x60/0x1b0 [ 160.832952] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 160.832952] RIP: 0033:0x7fe48f4c8154 Resolve this by getting RTNL earlier. This is safe because the subchannel work queue does trylock on RTNL and will detect the race. Fixes: 7b2ee50 ("hv_netvsc: common detach logic") Signed-off-by: Stephen Hemminger <[email protected]> Reviewed-by: Haiyang Zhang <[email protected]> Signed-off-by: David S. Miller <[email protected]>

…cm_qla2xxx_close_session() [ Upstream commit d4023db ] This patch avoids that lockdep reports the following warning: ===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 5.1.0-rc1-dbg+ torvalds#11 Tainted: G W ----------------------------------------------------- rmdir/1478 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: 00000000e7ac4607 (&(&k->k_lock)->rlock){+.+.}, at: klist_next+0x43/0x1d0 and this task is already holding: 00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx] which would create a new lock dependency: (&(&ha->tgt.sess_lock)->rlock){-...} -> (&(&k->k_lock)->rlock){+.+.} but this new dependency connects a HARDIRQ-irq-safe lock: (&(&ha->tgt.sess_lock)->rlock){-...} ... which became HARDIRQ-irq-safe at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx] qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx] qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx] qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx] __handle_irq_event_percpu+0x79/0x3c0 handle_irq_event_percpu+0x70/0xf0 handle_irq_event+0x5a/0x8b handle_edge_irq+0x12c/0x310 handle_irq+0x192/0x20a do_IRQ+0x73/0x160 ret_from_intr+0x0/0x1d default_idle+0x23/0x1f0 arch_cpu_idle+0x15/0x20 default_idle_call+0x35/0x40 do_idle+0x2bb/0x2e0 cpu_startup_entry+0x1d/0x20 start_secondary+0x24d/0x2d0 secondary_startup_64+0xa4/0xb0 to a HARDIRQ-irq-unsafe lock: (&(&k->k_lock)->rlock){+.+.} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&k->k_lock)->rlock); local_irq_disable(); lock(&(&ha->tgt.sess_lock)->rlock); lock(&(&k->k_lock)->rlock); <Interrupt> lock(&(&ha->tgt.sess_lock)->rlock); *** DEADLOCK *** 4 locks held by rmdir/1478: #0: 000000002c7f1ba4 (sb_writers#10){.+.+}, at: mnt_want_write+0x32/0x70 #1: 00000000c85eb147 (&default_group_class[depth - 1]#2/1){+.+.}, at: do_rmdir+0x217/0x2d0 #2: 000000002b164d6f (&sb->s_type->i_mutex_key#13){++++}, at: vfs_rmdir+0x7e/0x1d0 #3: 00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx] the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&(&ha->tgt.sess_lock)->rlock){-...} ops: 127 { IN-HARDIRQ-W at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx] qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx] qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx] qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx] __handle_irq_event_percpu+0x79/0x3c0 handle_irq_event_percpu+0x70/0xf0 handle_irq_event+0x5a/0x8b handle_edge_irq+0x12c/0x310 handle_irq+0x192/0x20a do_IRQ+0x73/0x160 ret_from_intr+0x0/0x1d default_idle+0x23/0x1f0 arch_cpu_idle+0x15/0x20 default_idle_call+0x35/0x40 do_idle+0x2bb/0x2e0 cpu_startup_entry+0x1d/0x20 start_secondary+0x24d/0x2d0 secondary_startup_64+0xa4/0xb0 INITIAL USE at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_loop_resync+0xb3d/0x2690 [qla2xxx] qla2x00_do_dpc+0xcee/0xf30 [qla2xxx] kthread+0x1d2/0x1f0 ret_from_fork+0x3a/0x50 } ... key at: [<ffffffffa125f700>] __key.62804+0x0/0xfffffffffff7e900 [qla2xxx] ... acquired at: __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&(&k->k_lock)->rlock){+.+.} ops: 14568 { HARDIRQ-ON-W at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 SOFTIRQ-ON-W at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 INITIAL USE at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 } ... key at: [<ffffffff83f3d900>] __key.15805+0x0/0x40 ... acquired at: __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe stack backtrace: CPU: 7 PID: 1478 Comm: rmdir Tainted: G W 5.1.0-rc1-dbg+ torvalds#11 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x86/0xca check_usage.cold.59+0x473/0x563 check_prev_add.constprop.43+0x1f1/0x1170 __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe Cc: Himanshu Madhani <[email protected]> Cc: Giridhar Malavali <[email protected]> Signed-off-by: Bart Van Assche <[email protected]> Acked-by: Himanshu Madhani <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit ff612ba ] We've been seeing the following sporadically throughout our fleet panic: kernel BUG at fs/btrfs/relocation.c:4584! netversion: 5.0-0 Backtrace: #0 [ffffc90003adb880] machine_kexec at ffffffff81041da8 #1 [ffffc90003adb8c8] __crash_kexec at ffffffff8110396c #2 [ffffc90003adb988] crash_kexec at ffffffff811048ad #3 [ffffc90003adb9a0] oops_end at ffffffff8101c19a #4 [ffffc90003adb9c0] do_trap at ffffffff81019114 #5 [ffffc90003adba00] do_error_trap at ffffffff810195d0 torvalds#6 [ffffc90003adbab0] invalid_op at ffffffff81a00a9b [exception RIP: btrfs_reloc_cow_block+692] RIP: ffffffff8143b614 RSP: ffffc90003adbb68 RFLAGS: 00010246 RAX: fffffffffffffff7 RBX: ffff8806b9c32000 RCX: ffff8806aad00690 RDX: ffff880850b295e0 RSI: ffff8806b9c32000 RDI: ffff88084f205bd0 RBP: ffff880849415000 R8: ffffc90003adbbe0 R9: ffff88085ac90000 R10: ffff8805f7369140 R11: 0000000000000000 R12: ffff880850b295e0 R13: ffff88084f205bd0 R14: 0000000000000000 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#7 [ffffc90003adbbb0] __btrfs_cow_block at ffffffff813bf1cd torvalds#8 [ffffc90003adbc28] btrfs_cow_block at ffffffff813bf4b3 torvalds#9 [ffffc90003adbc78] btrfs_search_slot at ffffffff813c2e6c The way relocation moves data extents is by creating a reloc inode and preallocating extents in this inode and then copying the data into these preallocated extents. Once we've done this for all of our extents, we'll write out these dirty pages, which marks the extent written, and goes into btrfs_reloc_cow_block(). From here we get our current reloc_control, which _should_ match the reloc_control for the current block group we're relocating. However if we get an ENOSPC in this path at some point we'll bail out, never initiating writeback on this inode. Not a huge deal, unless we happen to be doing relocation on a different block group, and this block group is now rc->stage == UPDATE_DATA_PTRS. This trips the BUG_ON() in btrfs_reloc_cow_block(), because we expect to be done modifying the data inode. We are in fact done modifying the metadata for the data inode we're currently using, but not the one from the failed block group, and thus we BUG_ON(). (This happens when writeback finishes for extents from the previous group, when we are at btrfs_finish_ordered_io() which updates the data reloc tree (inode item, drops/adds extent items, etc).) Fix this by writing out the reloc data inode always, and then breaking out of the loop after that point to keep from tripping this BUG_ON() later. Signed-off-by: Josef Bacik <[email protected]> Reviewed-by: Filipe Manana <[email protected]> [ add note from Filipe ] Signed-off-by: David Sterba <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

…text commit 0c9e8b3 upstream. stub_probe() and stub_disconnect() call functions which could call sleeping function in invalid context whil holding busid_lock. Fix the problem by refining the lock holds to short critical sections to change the busid_priv fields. This fix restructures the code to limit the lock holds in stub_probe() and stub_disconnect(). stub_probe(): [15217.927028] BUG: sleeping function called from invalid context at mm/slab.h:418 [15217.927038] in_atomic(): 1, irqs_disabled(): 0, pid: 29087, name: usbip [15217.927044] 5 locks held by usbip/29087: [15217.927047] #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0 [15217.927062] #1: 000000008f9ba75b (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0 [15217.927072] #2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50 [15217.927082] #3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50 [15217.927090] #4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host] [15217.927103] CPU: 3 PID: 29087 Comm: usbip Tainted: G W 5.1.0-rc6+ torvalds#40 [15217.927106] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013 [15217.927109] Call Trace: [15217.927118] dump_stack+0x63/0x85 [15217.927127] ___might_sleep+0xff/0x120 [15217.927133] __might_sleep+0x4a/0x80 [15217.927143] kmem_cache_alloc_trace+0x1aa/0x210 [15217.927156] stub_probe+0xe8/0x440 [usbip_host] [15217.927171] usb_probe_device+0x34/0x70 stub_disconnect(): [15279.182478] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908 [15279.182487] in_atomic(): 1, irqs_disabled(): 0, pid: 29114, name: usbip [15279.182492] 5 locks held by usbip/29114: [15279.182494] #0: 0000000091647f28 (sb_writers#6){....}, at: vfs_write+0x191/0x1c0 [15279.182506] #1: 00000000702cf0f3 (&of->mutex){....}, at: kernfs_fop_write+0xf7/0x1b0 [15279.182514] #2: 00000000872e5b4b (&dev->mutex){....}, at: __device_driver_lock+0x3b/0x50 [15279.182522] #3: 00000000e74ececc (&dev->mutex){....}, at: __device_driver_lock+0x46/0x50 [15279.182529] #4: 00000000b20abbe0 (&(&busid_table[i].busid_lock)->rlock){....}, at: get_busid_priv+0x48/0x60 [usbip_host] [15279.182541] CPU: 0 PID: 29114 Comm: usbip Tainted: G W 5.1.0-rc6+ torvalds#40 [15279.182543] Hardware name: Dell Inc. OptiPlex 790/0HY9JP, BIOS A18 09/24/2013 [15279.182546] Call Trace: [15279.182554] dump_stack+0x63/0x85 [15279.182561] ___might_sleep+0xff/0x120 [15279.182566] __might_sleep+0x4a/0x80 [15279.182574] __mutex_lock+0x55/0x950 [15279.182582] ? get_busid_priv+0x48/0x60 [usbip_host] [15279.182587] ? reacquire_held_locks+0xec/0x1a0 [15279.182591] ? get_busid_priv+0x48/0x60 [usbip_host] [15279.182597] ? find_held_lock+0x94/0xa0 [15279.182609] mutex_lock_nested+0x1b/0x20 [15279.182614] ? mutex_lock_nested+0x1b/0x20 [15279.182618] kernfs_remove_by_name_ns+0x2a/0x90 [15279.182625] sysfs_remove_file_ns+0x15/0x20 [15279.182629] device_remove_file+0x19/0x20 [15279.182634] stub_disconnect+0x6d/0x180 [usbip_host] [15279.182643] usb_unbind_device+0x27/0x60 Signed-off-by: Shuah Khan <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…emove commit d27e5e0 upstream. With this early return due to zfcp_unit child(ren), we don't use the zfcp_port reference from the earlier zfcp_get_port_by_wwpn() anymore and need to put it. Signed-off-by: Steffen Maier <[email protected]> Fixes: d99b601 ("[SCSI] zfcp: restore refcount check on port_remove") Cc: <[email protected]> #3.7+ Reviewed-by: Jens Remus <[email protected]> Reviewed-by: Benjamin Block <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 198790d ] In free_percpu() we sometimes call pcpu_schedule_balance_work() to queue a work item (which does a wakeup) while holding pcpu_lock. This creates an unnecessary lock dependency between pcpu_lock and the scheduler's pi_lock. There are other places where we call pcpu_schedule_balance_work() without hold pcpu_lock, and this case doesn't need to be different. Moving the call outside the lock prevents the following lockdep splat when running tools/testing/selftests/bpf/{test_maps,test_progs} in sequence with lockdep enabled: ====================================================== WARNING: possible circular locking dependency detected 5.1.0-dbg-DEV #1 Not tainted ------------------------------------------------------ kworker/23:255/18872 is trying to acquire lock: 000000000bc79290 (&(&pool->lock)->rlock){-.-.}, at: __queue_work+0xb2/0x520 but task is already holding lock: 00000000e3e7a6aa (pcpu_lock){..-.}, at: free_percpu+0x36/0x260 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (pcpu_lock){..-.}: lock_acquire+0x9e/0x180 _raw_spin_lock_irqsave+0x3a/0x50 pcpu_alloc+0xfa/0x780 __alloc_percpu_gfp+0x12/0x20 alloc_htab_elem+0x184/0x2b0 __htab_percpu_map_update_elem+0x252/0x290 bpf_percpu_hash_update+0x7c/0x130 __do_sys_bpf+0x1912/0x1be0 __x64_sys_bpf+0x1a/0x20 do_syscall_64+0x59/0x400 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #3 (&htab->buckets[i].lock){....}: lock_acquire+0x9e/0x180 _raw_spin_lock_irqsave+0x3a/0x50 htab_map_update_elem+0x1af/0x3a0 -> #2 (&rq->lock){-.-.}: lock_acquire+0x9e/0x180 _raw_spin_lock+0x2f/0x40 task_fork_fair+0x37/0x160 sched_fork+0x211/0x310 copy_process.part.43+0x7b1/0x2160 _do_fork+0xda/0x6b0 kernel_thread+0x29/0x30 rest_init+0x22/0x260 arch_call_rest_init+0xe/0x10 start_kernel+0x4fd/0x520 x86_64_start_reservations+0x24/0x26 x86_64_start_kernel+0x6f/0x72 secondary_startup_64+0xa4/0xb0 -> #1 (&p->pi_lock){-.-.}: lock_acquire+0x9e/0x180 _raw_spin_lock_irqsave+0x3a/0x50 try_to_wake_up+0x41/0x600 wake_up_process+0x15/0x20 create_worker+0x16b/0x1e0 workqueue_init+0x279/0x2ee kernel_init_freeable+0xf7/0x288 kernel_init+0xf/0x180 ret_from_fork+0x24/0x30 -> #0 (&(&pool->lock)->rlock){-.-.}: __lock_acquire+0x101f/0x12a0 lock_acquire+0x9e/0x180 _raw_spin_lock+0x2f/0x40 __queue_work+0xb2/0x520 queue_work_on+0x38/0x80 free_percpu+0x221/0x260 pcpu_freelist_destroy+0x11/0x20 stack_map_free+0x2a/0x40 bpf_map_free_deferred+0x3c/0x50 process_one_work+0x1f7/0x580 worker_thread+0x54/0x410 kthread+0x10f/0x150 ret_from_fork+0x24/0x30 other info that might help us debug this: Chain exists of: &(&pool->lock)->rlock --> &htab->buckets[i].lock --> pcpu_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pcpu_lock); lock(&htab->buckets[i].lock); lock(pcpu_lock); lock(&(&pool->lock)->rlock); *** DEADLOCK *** 3 locks held by kworker/23:255/18872: #0: 00000000b36a6e16 ((wq_completion)events){+.+.}, at: process_one_work+0x17a/0x580 #1: 00000000dfd966f0 ((work_completion)(&map->work)){+.+.}, at: process_one_work+0x17a/0x580 #2: 00000000e3e7a6aa (pcpu_lock){..-.}, at: free_percpu+0x36/0x260 stack backtrace: CPU: 23 PID: 18872 Comm: kworker/23:255 Not tainted 5.1.0-dbg-DEV #1 Hardware name: ... Workqueue: events bpf_map_free_deferred Call Trace: dump_stack+0x67/0x95 print_circular_bug.isra.38+0x1c6/0x220 check_prev_add.constprop.50+0x9f6/0xd20 __lock_acquire+0x101f/0x12a0 lock_acquire+0x9e/0x180 _raw_spin_lock+0x2f/0x40 __queue_work+0xb2/0x520 queue_work_on+0x38/0x80 free_percpu+0x221/0x260 pcpu_freelist_destroy+0x11/0x20 stack_map_free+0x2a/0x40 bpf_map_free_deferred+0x3c/0x50 process_one_work+0x1f7/0x580 worker_thread+0x54/0x410 kthread+0x10f/0x150 ret_from_fork+0x24/0x30 Signed-off-by: John Sperbeck <[email protected]> Signed-off-by: Dennis Zhou <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit 41be3e2 ] vfio_dev_present() which is the condition to wait_event_interruptible_timeout(), will call vfio_group_get_device and try to acquire the mutex group->device_lock. wait_event_interruptible_timeout() will set the state of the current task to TASK_INTERRUPTIBLE, before doing the condition check. This means that we will try to acquire the mutex while already in a sleeping state. The scheduler warns us by giving the following warning: [ 4050.264464] ------------[ cut here ]------------ [ 4050.264508] do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000b33c00e2>] prepare_to_wait_event+0x14a/0x188 [ 4050.264529] WARNING: CPU: 12 PID: 35924 at kernel/sched/core.c:6112 __might_sleep+0x76/0x90 .... 4050.264756] Call Trace: [ 4050.264765] ([<000000000017bbaa>] __might_sleep+0x72/0x90) [ 4050.264774] [<0000000000b97edc>] __mutex_lock+0x44/0x8c0 [ 4050.264782] [<0000000000b9878a>] mutex_lock_nested+0x32/0x40 [ 4050.264793] [<000003ff800d7abe>] vfio_group_get_device+0x36/0xa8 [vfio] [ 4050.264803] [<000003ff800d87c0>] vfio_del_group_dev+0x238/0x378 [vfio] [ 4050.264813] [<000003ff8015f67c>] mdev_remove+0x3c/0x68 [mdev] [ 4050.264825] [<00000000008e01b0>] device_release_driver_internal+0x168/0x268 [ 4050.264834] [<00000000008de692>] bus_remove_device+0x162/0x190 [ 4050.264843] [<00000000008daf42>] device_del+0x1e2/0x368 [ 4050.264851] [<00000000008db12c>] device_unregister+0x64/0x88 [ 4050.264862] [<000003ff8015ed84>] mdev_device_remove+0xec/0x130 [mdev] [ 4050.264872] [<000003ff8015f074>] remove_store+0x6c/0xa8 [mdev] [ 4050.264881] [<000000000046f494>] kernfs_fop_write+0x14c/0x1f8 [ 4050.264890] [<00000000003c1530>] __vfs_write+0x38/0x1a8 [ 4050.264899] [<00000000003c187c>] vfs_write+0xb4/0x198 [ 4050.264908] [<00000000003c1af2>] ksys_write+0x5a/0xb0 [ 4050.264916] [<0000000000b9e270>] system_call+0xdc/0x2d8 [ 4050.264925] 4 locks held by sh/35924: [ 4050.264933] #0: 000000001ef90325 (sb_writers#4){.+.+}, at: vfs_write+0x9e/0x198 [ 4050.264948] #1: 000000005c1ab0b3 (&of->mutex){+.+.}, at: kernfs_fop_write+0x1cc/0x1f8 [ 4050.264963] #2: 0000000034831ab8 (kn->count#297){++++}, at: kernfs_remove_self+0x12e/0x150 [ 4050.264979] #3: 00000000e152484f (&dev->mutex){....}, at: device_release_driver_internal+0x5c/0x268 [ 4050.264993] Last Breaking-Event-Address: [ 4050.265002] [<000000000017bbaa>] __might_sleep+0x72/0x90 [ 4050.265010] irq event stamp: 7039 [ 4050.265020] hardirqs last enabled at (7047): [<00000000001cee7a>] console_unlock+0x6d2/0x740 [ 4050.265029] hardirqs last disabled at (7054): [<00000000001ce87e>] console_unlock+0xd6/0x740 [ 4050.265040] softirqs last enabled at (6416): [<0000000000b8fe26>] __udelay+0xb6/0x100 [ 4050.265049] softirqs last disabled at (6415): [<0000000000b8fe06>] __udelay+0x96/0x100 [ 4050.265057] ---[ end trace d04a07d39d99a9f9 ]--- Let's fix this as described in the article https://lwn.net/Articles/628628/. Signed-off-by: Farhan Ali <[email protected]> [remove now redundant vfio_dev_present()] Signed-off-by: Alex Williamson <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit 347ab94 ] This patch fixes deadlock warning if removing PWM device when CONFIG_PROVE_LOCKING is enabled. This issue can be reproceduced by the following steps on the R-Car H3 Salvator-X board if the backlight is disabled: # cd /sys/class/pwm/pwmchip0 # echo 0 > export # ls device export npwm power pwm0 subsystem uevent unexport # cd device/driver # ls bind e6e31000.pwm uevent unbind # echo e6e31000.pwm > unbind [ 87.659974] ====================================================== [ 87.666149] WARNING: possible circular locking dependency detected [ 87.672327] 5.0.0 torvalds#7 Not tainted [ 87.675549] ------------------------------------------------------ [ 87.681723] bash/2986 is trying to acquire lock: [ 87.686337] 000000005ea0e178 (kn->count#58){++++}, at: kernfs_remove_by_name_ns+0x50/0xa0 [ 87.694528] [ 87.694528] but task is already holding lock: [ 87.700353] 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.707405] [ 87.707405] which lock already depends on the new lock. [ 87.707405] [ 87.715574] [ 87.715574] the existing dependency chain (in reverse order) is: [ 87.723048] [ 87.723048] -> #1 (pwm_lock){+.+.}: [ 87.728017] __mutex_lock+0x70/0x7e4 [ 87.732108] mutex_lock_nested+0x1c/0x24 [ 87.736547] pwm_request_from_chip.part.6+0x34/0x74 [ 87.741940] pwm_request_from_chip+0x20/0x40 [ 87.746725] export_store+0x6c/0x1f4 [ 87.750820] dev_attr_store+0x18/0x28 [ 87.754998] sysfs_kf_write+0x54/0x64 [ 87.759175] kernfs_fop_write+0xe4/0x1e8 [ 87.763615] __vfs_write+0x40/0x184 [ 87.767619] vfs_write+0xa8/0x19c [ 87.771448] ksys_write+0x58/0xbc [ 87.775278] __arm64_sys_write+0x18/0x20 [ 87.779721] el0_svc_common+0xd0/0x124 [ 87.783986] el0_svc_compat_handler+0x1c/0x24 [ 87.788858] el0_svc_compat+0x8/0x18 [ 87.792947] [ 87.792947] -> #0 (kn->count#58){++++}: [ 87.798260] lock_acquire+0xc4/0x22c [ 87.802353] __kernfs_remove+0x258/0x2c4 [ 87.806790] kernfs_remove_by_name_ns+0x50/0xa0 [ 87.811836] remove_files.isra.1+0x38/0x78 [ 87.816447] sysfs_remove_group+0x48/0x98 [ 87.820971] sysfs_remove_groups+0x34/0x4c [ 87.825583] device_remove_attrs+0x6c/0x7c [ 87.830197] device_del+0x11c/0x33c [ 87.834201] device_unregister+0x14/0x2c [ 87.838638] pwmchip_sysfs_unexport+0x40/0x4c [ 87.843509] pwmchip_remove+0xf4/0x13c [ 87.847773] rcar_pwm_remove+0x28/0x34 [ 87.852039] platform_drv_remove+0x24/0x64 [ 87.856651] device_release_driver_internal+0x18c/0x21c [ 87.862391] device_release_driver+0x14/0x1c [ 87.867175] unbind_store+0xe0/0x124 [ 87.871265] drv_attr_store+0x20/0x30 [ 87.875442] sysfs_kf_write+0x54/0x64 [ 87.879618] kernfs_fop_write+0xe4/0x1e8 [ 87.884055] __vfs_write+0x40/0x184 [ 87.888057] vfs_write+0xa8/0x19c [ 87.891887] ksys_write+0x58/0xbc [ 87.895716] __arm64_sys_write+0x18/0x20 [ 87.900154] el0_svc_common+0xd0/0x124 [ 87.904417] el0_svc_compat_handler+0x1c/0x24 [ 87.909289] el0_svc_compat+0x8/0x18 [ 87.913378] [ 87.913378] other info that might help us debug this: [ 87.913378] [ 87.921374] Possible unsafe locking scenario: [ 87.921374] [ 87.927286] CPU0 CPU1 [ 87.931808] ---- ---- [ 87.936331] lock(pwm_lock); [ 87.939293] lock(kn->count#58); [ 87.945120] lock(pwm_lock); [ 87.950599] lock(kn->count#58); [ 87.953908] [ 87.953908] *** DEADLOCK *** [ 87.953908] [ 87.959821] 4 locks held by bash/2986: [ 87.963563] #0: 00000000ace7bc30 (sb_writers#6){.+.+}, at: vfs_write+0x188/0x19c [ 87.971044] #1: 00000000287991b2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xb4/0x1e8 [ 87.978872] #2: 00000000f739d016 (&dev->mutex){....}, at: device_release_driver_internal+0x40/0x21c [ 87.988001] #3: 000000006313b17c (pwm_lock){+.+.}, at: pwmchip_remove+0x28/0x13c [ 87.995481] [ 87.995481] stack backtrace: [ 87.999836] CPU: 0 PID: 2986 Comm: bash Not tainted 5.0.0 torvalds#7 [ 88.005489] Hardware name: Renesas Salvator-X board based on r8a7795 ES1.x (DT) [ 88.012791] Call trace: [ 88.015235] dump_backtrace+0x0/0x190 [ 88.018891] show_stack+0x14/0x1c [ 88.022204] dump_stack+0xb0/0xec [ 88.025514] print_circular_bug.isra.32+0x1d0/0x2e0 [ 88.030385] __lock_acquire+0x1318/0x1864 [ 88.034388] lock_acquire+0xc4/0x22c [ 88.037958] __kernfs_remove+0x258/0x2c4 [ 88.041874] kernfs_remove_by_name_ns+0x50/0xa0 [ 88.046398] remove_files.isra.1+0x38/0x78 [ 88.050487] sysfs_remove_group+0x48/0x98 [ 88.054490] sysfs_remove_groups+0x34/0x4c [ 88.058580] device_remove_attrs+0x6c/0x7c [ 88.062671] device_del+0x11c/0x33c [ 88.066154] device_unregister+0x14/0x2c [ 88.070070] pwmchip_sysfs_unexport+0x40/0x4c [ 88.074421] pwmchip_remove+0xf4/0x13c [ 88.078163] rcar_pwm_remove+0x28/0x34 [ 88.081906] platform_drv_remove+0x24/0x64 [ 88.085996] device_release_driver_internal+0x18c/0x21c [ 88.091215] device_release_driver+0x14/0x1c [ 88.095478] unbind_store+0xe0/0x124 [ 88.099048] drv_attr_store+0x20/0x30 [ 88.102704] sysfs_kf_write+0x54/0x64 [ 88.106359] kernfs_fop_write+0xe4/0x1e8 [ 88.110275] __vfs_write+0x40/0x184 [ 88.113757] vfs_write+0xa8/0x19c [ 88.117065] ksys_write+0x58/0xbc [ 88.120374] __arm64_sys_write+0x18/0x20 [ 88.124291] el0_svc_common+0xd0/0x124 [ 88.128034] el0_svc_compat_handler+0x1c/0x24 [ 88.132384] el0_svc_compat+0x8/0x18 The sysfs unexport in pwmchip_remove() is completely asymmetric to what we do in pwmchip_add_with_polarity() and commit 0733424 ("pwm: Unexport children before chip removal") is a strong indication that this was wrong to begin with. We should just move pwmchip_sysfs_unexport() where it belongs, which is right after pwmchip_sysfs_unexport_children(). In that case, we do not need separate functions anymore either. We also really want to remove sysfs irrespective of whether or not the chip will be removed as a result of pwmchip_remove(). We can only assume that the driver will be gone after that, so we shouldn't leave any dangling sysfs files around. This warning disappears if we move pwmchip_sysfs_unexport() to the top of pwmchip_remove(), pwmchip_sysfs_unexport_children(). That way it is also outside of the pwm_lock section, which indeed doesn't seem to be needed. Moving the pwmchip_sysfs_export() call outside of that section also seems fine and it'd be perfectly symmetric with pwmchip_remove() again. So, this patch fixes them. Signed-off-by: Phong Hoang <[email protected]> [shimoda: revise the commit log and code] Fixes: 76abbdd ("pwm: Add sysfs interface") Fixes: 0733424 ("pwm: Unexport children before chip removal") Signed-off-by: Yoshihiro Shimoda <[email protected]> Tested-by: Hoan Nguyen An <[email protected]> Reviewed-by: Geert Uytterhoeven <[email protected]> Reviewed-by: Simon Horman <[email protected]> Reviewed-by: Uwe Kleine-König <[email protected]> Signed-off-by: Thierry Reding <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit a58f2ce upstream. There was the below bug report from Wu Fangsuo. On the CMA allocation path, isolate_migratepages_range() could isolate unevictable LRU pages and reclaim_clean_page_from_list() can try to reclaim them if they are clean file-backed pages. page:ffffffbf02f33b40 count:86 mapcount:84 mapping:ffffffc08fa7a810 index:0x24 flags: 0x19040c(referenced|uptodate|arch_1|mappedtodisk|unevictable|mlocked) raw: 000000000019040c ffffffc08fa7a810 0000000000000024 0000005600000053 raw: ffffffc009b05b20 ffffffc009b05b20 0000000000000000 ffffffc09bf3ee80 page dumped because: VM_BUG_ON_PAGE(PageLRU(page) || PageUnevictable(page)) page->mem_cgroup:ffffffc09bf3ee80 ------------[ cut here ]------------ kernel BUG at /home/build/farmland/adroid9.0/kernel/linux/mm/vmscan.c:1350! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 7125 Comm: syz-executor Tainted: G S 4.14.81 #3 Hardware name: ASR AQUILAC EVB (DT) task: ffffffc00a54cd00 task.stack: ffffffc009b00000 PC is at shrink_page_list+0x1998/0x3240 LR is at shrink_page_list+0x1998/0x3240 pc : [<ffffff90083a2158>] lr : [<ffffff90083a2158>] pstate: 60400045 sp : ffffffc009b05940 .. shrink_page_list+0x1998/0x3240 reclaim_clean_pages_from_list+0x3c0/0x4f0 alloc_contig_range+0x3bc/0x650 cma_alloc+0x214/0x668 ion_cma_allocate+0x98/0x1d8 ion_alloc+0x200/0x7e0 ion_ioctl+0x18c/0x378 do_vfs_ioctl+0x17c/0x1780 SyS_ioctl+0xac/0xc0 Wu found it's due to commit ad6b670 ("mm: remove SWAP_MLOCK in ttu"). Before that, unevictable pages go to cull_mlocked so that we can't reach the VM_BUG_ON_PAGE line. To fix the issue, this patch filters out unevictable LRU pages from the reclaim_clean_pages_from_list in CMA. Link: http://lkml.kernel.org/r/[email protected] Fixes: ad6b670 ("mm: remove SWAP_MLOCK in ttu") Signed-off-by: Minchan Kim <[email protected]> Reported-by: Wu Fangsuo <[email protected]> Debugged-by: Wu Fangsuo <[email protected]> Tested-by: Wu Fangsuo <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Pankaj Suryawanshi <[email protected]> Cc: <[email protected]> [4.12+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit bc71d8b upstream. When virt_wifi interface is created, virt_wifi_newlink() is called and it calls register_netdevice(). if register_netdevice() fails, it internally would call ->priv_destructor(), which is virt_wifi_net_device_destructor() and it frees netdev. but virt_wifi_newlink() still use netdev. So, use-after-free would occur in virt_wifi_newlink(). Test commands: ip link add dummy0 type dummy modprobe bonding ip link add bonding_masters link dummy0 type virt_wifi Splat looks like: [ 202.220554] BUG: KASAN: use-after-free in virt_wifi_newlink+0x88b/0x9a0 [virt_wifi] [ 202.221659] Read of size 8 at addr ffff888061629cb8 by task ip/852 [ 202.222896] CPU: 1 PID: 852 Comm: ip Not tainted 5.4.0-rc5 #3 [ 202.223765] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 202.225073] Call Trace: [ 202.225532] dump_stack+0x7c/0xbb [ 202.226869] print_address_description.constprop.5+0x1be/0x360 [ 202.229362] __kasan_report+0x12a/0x16f [ 202.230714] kasan_report+0xe/0x20 [ 202.232595] virt_wifi_newlink+0x88b/0x9a0 [virt_wifi] [ 202.233370] __rtnl_newlink+0xb9f/0x11b0 [ 202.244909] rtnl_newlink+0x65/0x90 [ ... ] Cc: [email protected] Fixes: c7cdba3 ("mac80211-next: rtnetlink wifi simulation device") Signed-off-by: Taehee Yoo <[email protected]> Link: https://lore.kernel.org/r/[email protected] [trim stack dump a bit] Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

The current rbtree for service ranges in the name table is built based on the 'lower' & 'upper' range values resulting in a flaw in the rbtree searching. Some issues have been observed in case of range overlapping: Case #1: unable to withdraw a name entry: After some name services are bound, all of them are withdrawn by user but one remains in the name table forever. This corrupts the table and that service becomes dummy i.e. no real port. E.g. / {22, 22} / / ---> {10, 50} / \ / \ {10, 30} {20, 60} The node {10, 30} cannot be removed since the rbtree searching stops at the node's ancestor i.e. {10, 50}, so starting from it will never reach the finding node. Case #2: failed to send data in some cases: E.g. Two service ranges: {20, 60}, {10, 50} are bound. The rbtree for this service will be one of the two cases below depending on the order of the bindings: {20, 60} {10, 50} <-- / \ / \ / \ / \ {10, 50} NIL <-- NIL {20, 60} (a) (b) Now, try to send some data to service {30}, there will be two results: (a): Failed, no route to host. (b): Ok. The reason is that the rbtree searching will stop at the pointing node as shown above. Case #3: Same as case #2b above but if the data sending's scope is local and the {10, 50} is published by a peer node, then it will result in 'no route to host' even though the other {20, 60} is for example on the local node which should be able to get the data. The issues are actually due to the way we built the rbtree. This commit fixes it by introducing an additional field to each node - named 'max', which is the largest 'upper' of that node subtree. The 'max' value for each subtrees will be propagated correctly whenever a node is inserted/ removed or the tree is rebalanced by the augmented rbtree callbacks. By this way, we can change the rbtree searching appoarch to solve the issues above. Another benefit from this is that we can now improve the searching for a next range matching e.g. in case of multicast, so get rid of the unneeded looping over all nodes in the tree. Acked-by: Jon Maloy <[email protected]> Signed-off-by: Tuong Lien <[email protected]> Signed-off-by: David S. Miller <[email protected]>

We got another syzbot report [1] that tells us we must use write_lock_irq()/write_unlock_irq() to avoid possible deadlock. [1] WARNING: inconsistent lock state 5.5.0-rc1-syzkaller #0 Not tainted -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-R} usage. syz-executor826/9605 [HC1[1]:SC0[0]:HE0:SE1] takes: ffffffff8a128718 (disc_data_lock){+-..}, at: sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138 {HARDIRQ-ON-W} state was registered at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x33/0x50 kernel/locking/spinlock.c:319 sixpack_close+0x1d/0x250 drivers/net/hamradio/6pack.c:657 tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:489 tty_set_ldisc+0x230/0x6b0 drivers/tty/tty_ldisc.c:585 tiocsetd drivers/tty/tty_io.c:2337 [inline] tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2597 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe irq event stamp: 3946 hardirqs last enabled at (3945): [<ffffffff87c86e43>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (3945): [<ffffffff87c86e43>] _raw_spin_unlock_irq+0x23/0x80 kernel/locking/spinlock.c:199 hardirqs last disabled at (3946): [<ffffffff8100675f>] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42 softirqs last enabled at (2658): [<ffffffff86a8b4df>] spin_unlock_bh include/linux/spinlock.h:383 [inline] softirqs last enabled at (2658): [<ffffffff86a8b4df>] clusterip_netdev_event+0x46f/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:222 softirqs last disabled at (2656): [<ffffffff86a8b22b>] spin_lock_bh include/linux/spinlock.h:343 [inline] softirqs last disabled at (2656): [<ffffffff86a8b22b>] clusterip_netdev_event+0x1bb/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:196 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(disc_data_lock); <Interrupt> lock(disc_data_lock); *** DEADLOCK *** 5 locks held by syz-executor826/9605: #0: ffff8880a905e198 (&tty->legacy_mutex){+.+.}, at: tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19 #1: ffffffff899a56c0 (rcu_read_lock){....}, at: mutex_spin_on_owner+0x0/0x330 kernel/locking/mutex.c:413 #2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: serial8250_interrupt+0x2d/0x1a0 drivers/tty/serial/8250/8250_core.c:116 #3: ffffffff8c104048 (&port_lock_key){-.-.}, at: serial8250_handle_irq.part.0+0x24/0x330 drivers/tty/serial/8250/8250_port.c:1823 #4: ffff8880a905e090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref+0x22/0x90 drivers/tty/tty_ldisc.c:288 stack backtrace: CPU: 1 PID: 9605 Comm: syz-executor826 Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_usage_bug.cold+0x327/0x378 kernel/locking/lockdep.c:3101 valid_state kernel/locking/lockdep.c:3112 [inline] mark_lock_irq kernel/locking/lockdep.c:3309 [inline] mark_lock+0xbb4/0x1220 kernel/locking/lockdep.c:3666 mark_usage kernel/locking/lockdep.c:3554 [inline] __lock_acquire+0x1e55/0x4a00 kernel/locking/lockdep.c:3909 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x50 kernel/locking/spinlock.c:223 sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138 sixpack_write_wakeup+0x25/0x340 drivers/net/hamradio/6pack.c:402 tty_wakeup+0xe9/0x120 drivers/tty/tty_io.c:536 tty_port_default_wakeup+0x2b/0x40 drivers/tty/tty_port.c:50 tty_port_tty_wakeup+0x57/0x70 drivers/tty/tty_port.c:387 uart_write_wakeup+0x46/0x70 drivers/tty/serial/serial_core.c:104 serial8250_tx_chars+0x495/0xaf0 drivers/tty/serial/8250/8250_port.c:1761 serial8250_handle_irq.part.0+0x2a2/0x330 drivers/tty/serial/8250/8250_port.c:1834 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1820 [inline] serial8250_default_handle_irq+0xc0/0x150 drivers/tty/serial/8250/8250_port.c:1850 serial8250_interrupt+0xf1/0x1a0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x15d/0x970 kernel/irq/handle.c:149 handle_irq_event_percpu+0x74/0x160 kernel/irq/handle.c:189 handle_irq_event+0xa7/0x134 kernel/irq/handle.c:206 handle_edge_irq+0x25e/0x8d0 kernel/irq/chip.c:830 generic_handle_irq_desc include/linux/irqdesc.h:156 [inline] do_IRQ+0xde/0x280 arch/x86/kernel/irq.c:250 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:607 </IRQ> RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:685 [inline] RIP: 0010:mutex_spin_on_owner+0x247/0x330 kernel/locking/mutex.c:579 Code: c3 be 08 00 00 00 4c 89 e7 e8 e5 06 59 00 4c 89 e0 48 c1 e8 03 42 80 3c 38 00 0f 85 e1 00 00 00 49 8b 04 24 a8 01 75 96 f3 90 <e9> 2f fe ff ff 0f 0b e8 0d 19 09 00 84 c0 0f 85 ff fd ff ff 48 c7 RSP: 0018:ffffc90001eafa20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffd7 RAX: 0000000000000000 RBX: ffff88809fd9e0c0 RCX: 1ffffffff13266dd RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000 RBP: ffffc90001eafa60 R08: 1ffff11013d22898 R09: ffffed1013d22899 R10: ffffed1013d22898 R11: ffff88809e9144c7 R12: ffff8880a905e138 R13: ffff88809e9144c0 R14: 0000000000000000 R15: dffffc0000000000 mutex_optimistic_spin kernel/locking/mutex.c:673 [inline] __mutex_lock_common kernel/locking/mutex.c:962 [inline] __mutex_lock+0x32b/0x13c0 kernel/locking/mutex.c:1106 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121 tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19 tty_release+0xb5/0xe90 drivers/tty/tty_io.c:1665 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x8e7/0x2ef0 kernel/exit.c:797 do_group_exit+0x135/0x360 kernel/exit.c:895 __do_sys_exit_group kernel/exit.c:906 [inline] __se_sys_exit_group kernel/exit.c:904 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:904 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x43fef8 Code: Bad RIP value. RSP: 002b:00007ffdb07d2338 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fef8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004bf730 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 Fixes: 6e4e2f8 ("6pack,mkiss: fix lock inconsistency") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: syzbot <[email protected]> Cc: Arnd Bergmann <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]>

[ Upstream commit 32546a9 ] This patch moves the final part of the cifsFileInfo_put() logic where we need a write lock on lock_sem to be processed in a separate thread that holds no other locks. This is to prevent deadlocks like the one below: > there are 6 processes looping to while trying to down_write > cinode->lock_sem, 5 of them from _cifsFileInfo_put, and one from > cifs_new_fileinfo > > and there are 5 other processes which are blocked, several of them > waiting on either PG_writeback or PG_locked (which are both set), all > for the same page of the file > > 2 inode_lock() (inode->i_rwsem) for the file > 1 wait_on_page_writeback() for the page > 1 down_read(inode->i_rwsem) for the inode of the directory > 1 inode_lock()(inode->i_rwsem) for the inode of the directory > 1 __lock_page > > > so processes are blocked waiting on: > page flags PG_locked and PG_writeback for one specific page > inode->i_rwsem for the directory > inode->i_rwsem for the file > cifsInodeInflock_sem > > > > here are the more gory details (let me know if I need to provide > anything more/better): > > [0 00:48:22.765] [UN] PID: 8863 TASK: ffff8c691547c5c0 CPU: 3 > COMMAND: "reopen_file" > #0 [ffff9965007e3ba8] __schedule at ffffffff9b6e6095 > #1 [ffff9965007e3c38] schedule at ffffffff9b6e64df > #2 [ffff9965007e3c48] rwsem_down_write_slowpath at ffffffff9af283d7 > #3 [ffff9965007e3cb8] legitimize_path at ffffffff9b0f975d > #4 [ffff9965007e3d08] path_openat at ffffffff9b0fe55d > #5 [ffff9965007e3dd8] do_filp_open at ffffffff9b100a33 > torvalds#6 [ffff9965007e3ee0] do_sys_open at ffffffff9b0eb2d6 > torvalds#7 [ffff9965007e3f38] do_syscall_64 at ffffffff9ae04315 > * (I think legitimize_path is bogus) > > in path_openat > } else { > const char *s = path_init(nd, flags); > while (!(error = link_path_walk(s, nd)) && > (error = do_last(nd, file, op)) > 0) { <<<< > > do_last: > if (open_flag & O_CREAT) > inode_lock(dir->d_inode); <<<< > else > so it's trying to take inode->i_rwsem for the directory > > DENTRY INODE SUPERBLK TYPE PATH > ffff8c68bb8e79c0 ffff8c691158ef20 ffff8c6915bf9000 DIR /mnt/vm1_smb/ > inode.i_rwsem is ffff8c691158efc0 > > <struct rw_semaphore 0xffff8c691158efc0>: > owner: <struct task_struct 0xffff8c6914275d00> (UN - 8856 - > reopen_file), counter: 0x0000000000000003 > waitlist: 2 > 0xffff9965007e3c90 8863 reopen_file UN 0 1:29:22.926 > RWSEM_WAITING_FOR_WRITE > 0xffff996500393e00 9802 ls UN 0 1:17:26.700 > RWSEM_WAITING_FOR_READ > > > the owner of the inode.i_rwsem of the directory is: > > [0 00:00:00.109] [UN] PID: 8856 TASK: ffff8c6914275d00 CPU: 3 > COMMAND: "reopen_file" > #0 [ffff99650065b828] __schedule at ffffffff9b6e6095 > #1 [ffff99650065b8b8] schedule at ffffffff9b6e64df > #2 [ffff99650065b8c8] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff99650065b940] msleep at ffffffff9af573a9 > #4 [ffff99650065b948] _cifsFileInfo_put.cold.63 at ffffffffc0a42dd6 [cifs] > #5 [ffff99650065ba38] cifs_writepage_locked at ffffffffc0a0b8f3 [cifs] > torvalds#6 [ffff99650065bab0] cifs_launder_page at ffffffffc0a0bb72 [cifs] > torvalds#7 [ffff99650065bb30] invalidate_inode_pages2_range at ffffffff9b04d4bd > torvalds#8 [ffff99650065bcb8] cifs_invalidate_mapping at ffffffffc0a11339 [cifs] > torvalds#9 [ffff99650065bcd0] cifs_revalidate_mapping at ffffffffc0a1139a [cifs] > torvalds#10 [ffff99650065bcf0] cifs_d_revalidate at ffffffffc0a014f6 [cifs] > torvalds#11 [ffff99650065bd08] path_openat at ffffffff9b0fe7f7 > torvalds#12 [ffff99650065bdd8] do_filp_open at ffffffff9b100a33 > torvalds#13 [ffff99650065bee0] do_sys_open at ffffffff9b0eb2d6 > torvalds#14 [ffff99650065bf38] do_syscall_64 at ffffffff9ae04315 > > cifs_launder_page is for page 0xffffd1e2c07d2480 > > crash> page.index,mapping,flags 0xffffd1e2c07d2480 > index = 0x8 > mapping = 0xffff8c68f3cd0db0 > flags = 0xfffffc0008095 > > PAGE-FLAG BIT VALUE > PG_locked 0 0000001 > PG_uptodate 2 0000004 > PG_lru 4 0000010 > PG_waiters 7 0000080 > PG_writeback 15 0008000 > > > inode is ffff8c68f3cd0c40 > inode.i_rwsem is ffff8c68f3cd0ce0 > DENTRY INODE SUPERBLK TYPE PATH > ffff8c68a1f1b480 ffff8c68f3cd0c40 ffff8c6915bf9000 REG > /mnt/vm1_smb/testfile.8853 > > > this process holds the inode->i_rwsem for the parent directory, is > laundering a page attached to the inode of the file it's opening, and in > _cifsFileInfo_put is trying to down_write the cifsInodeInflock_sem > for the file itself. > > > <struct rw_semaphore 0xffff8c68f3cd0ce0>: > owner: <struct task_struct 0xffff8c6914272e80> (UN - 8854 - > reopen_file), counter: 0x0000000000000003 > waitlist: 1 > 0xffff9965005dfd80 8855 reopen_file UN 0 1:29:22.912 > RWSEM_WAITING_FOR_WRITE > > this is the inode.i_rwsem for the file > > the owner: > > [0 00:48:22.739] [UN] PID: 8854 TASK: ffff8c6914272e80 CPU: 2 > COMMAND: "reopen_file" > #0 [ffff99650054fb38] __schedule at ffffffff9b6e6095 > #1 [ffff99650054fbc8] schedule at ffffffff9b6e64df > #2 [ffff99650054fbd8] io_schedule at ffffffff9b6e68e2 > #3 [ffff99650054fbe8] __lock_page at ffffffff9b03c56f > #4 [ffff99650054fc80] pagecache_get_page at ffffffff9b03dcdf > #5 [ffff99650054fcc0] grab_cache_page_write_begin at ffffffff9b03ef4c > torvalds#6 [ffff99650054fcd0] cifs_write_begin at ffffffffc0a064ec [cifs] > torvalds#7 [ffff99650054fd30] generic_perform_write at ffffffff9b03bba4 > torvalds#8 [ffff99650054fda8] __generic_file_write_iter at ffffffff9b04060a > torvalds#9 [ffff99650054fdf0] cifs_strict_writev.cold.70 at ffffffffc0a4469b [cifs] > torvalds#10 [ffff99650054fe48] new_sync_write at ffffffff9b0ec1dd > torvalds#11 [ffff99650054fed0] vfs_write at ffffffff9b0eed35 > torvalds#12 [ffff99650054ff00] ksys_write at ffffffff9b0eefd9 > torvalds#13 [ffff99650054ff38] do_syscall_64 at ffffffff9ae04315 > > the process holds the inode->i_rwsem for the file to which it's writing, > and is trying to __lock_page for the same page as in the other processes > > > the other tasks: > [0 00:00:00.028] [UN] PID: 8859 TASK: ffff8c6915479740 CPU: 2 > COMMAND: "reopen_file" > #0 [ffff9965007b39d8] __schedule at ffffffff9b6e6095 > #1 [ffff9965007b3a68] schedule at ffffffff9b6e64df > #2 [ffff9965007b3a78] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff9965007b3af0] msleep at ffffffff9af573a9 > #4 [ffff9965007b3af8] cifs_new_fileinfo.cold.61 at ffffffffc0a42a07 [cifs] > #5 [ffff9965007b3b78] cifs_open at ffffffffc0a0709d [cifs] > torvalds#6 [ffff9965007b3cd8] do_dentry_open at ffffffff9b0e9b7a > torvalds#7 [ffff9965007b3d08] path_openat at ffffffff9b0fe34f > torvalds#8 [ffff9965007b3dd8] do_filp_open at ffffffff9b100a33 > torvalds#9 [ffff9965007b3ee0] do_sys_open at ffffffff9b0eb2d6 > torvalds#10 [ffff9965007b3f38] do_syscall_64 at ffffffff9ae04315 > > this is opening the file, and is trying to down_write cinode->lock_sem > > > [0 00:00:00.041] [UN] PID: 8860 TASK: ffff8c691547ae80 CPU: 2 > COMMAND: "reopen_file" > [0 00:00:00.057] [UN] PID: 8861 TASK: ffff8c6915478000 CPU: 3 > COMMAND: "reopen_file" > [0 00:00:00.059] [UN] PID: 8858 TASK: ffff8c6914271740 CPU: 2 > COMMAND: "reopen_file" > [0 00:00:00.109] [UN] PID: 8862 TASK: ffff8c691547dd00 CPU: 6 > COMMAND: "reopen_file" > #0 [ffff9965007c3c78] __schedule at ffffffff9b6e6095 > #1 [ffff9965007c3d08] schedule at ffffffff9b6e64df > #2 [ffff9965007c3d18] schedule_timeout at ffffffff9b6e9f89 > #3 [ffff9965007c3d90] msleep at ffffffff9af573a9 > #4 [ffff9965007c3d98] _cifsFileInfo_put.cold.63 at ffffffffc0a42dd6 [cifs] > #5 [ffff9965007c3e88] cifs_close at ffffffffc0a07aaf [cifs] > torvalds#6 [ffff9965007c3ea0] __fput at ffffffff9b0efa6e > torvalds#7 [ffff9965007c3ee8] task_work_run at ffffffff9aef1614 > torvalds#8 [ffff9965007c3f20] exit_to_usermode_loop at ffffffff9ae03d6f > torvalds#9 [ffff9965007c3f38] do_syscall_64 at ffffffff9ae0444c > > closing the file, and trying to down_write cifsi->lock_sem > > > [0 00:48:22.839] [UN] PID: 8857 TASK: ffff8c6914270000 CPU: 7 > COMMAND: "reopen_file" > #0 [ffff9965006a7cc8] __schedule at ffffffff9b6e6095 > #1 [ffff9965006a7d58] schedule at ffffffff9b6e64df > #2 [ffff9965006a7d68] io_schedule at ffffffff9b6e68e2 > #3 [ffff9965006a7d78] wait_on_page_bit at ffffffff9b03cac6 > #4 [ffff9965006a7e10] __filemap_fdatawait_range at ffffffff9b03b028 > #5 [ffff9965006a7ed8] filemap_write_and_wait at ffffffff9b040165 > torvalds#6 [ffff9965006a7ef0] cifs_flush at ffffffffc0a0c2fa [cifs] > torvalds#7 [ffff9965006a7f10] filp_close at ffffffff9b0e93f1 > torvalds#8 [ffff9965006a7f30] __x64_sys_close at ffffffff9b0e9a0e > torvalds#9 [ffff9965006a7f38] do_syscall_64 at ffffffff9ae04315 > > in __filemap_fdatawait_range > wait_on_page_writeback(page); > for the same page of the file > > > > [0 00:48:22.718] [UN] PID: 8855 TASK: ffff8c69142745c0 CPU: 7 > COMMAND: "reopen_file" > #0 [ffff9965005dfc98] __schedule at ffffffff9b6e6095 > #1 [ffff9965005dfd28] schedule at ffffffff9b6e64df > #2 [ffff9965005dfd38] rwsem_down_write_slowpath at ffffffff9af283d7 > #3 [ffff9965005dfdf0] cifs_strict_writev at ffffffffc0a0c40a [cifs] > #4 [ffff9965005dfe48] new_sync_write at ffffffff9b0ec1dd > #5 [ffff9965005dfed0] vfs_write at ffffffff9b0eed35 > torvalds#6 [ffff9965005dff00] ksys_write at ffffffff9b0eefd9 > torvalds#7 [ffff9965005dff38] do_syscall_64 at ffffffff9ae04315 > > inode_lock(inode); > > > and one 'ls' later on, to see whether the rest of the mount is available > (the test file is in the root, so we get blocked up on the directory > ->i_rwsem), so the entire mount is unavailable > > [0 00:36:26.473] [UN] PID: 9802 TASK: ffff8c691436ae80 CPU: 4 > COMMAND: "ls" > #0 [ffff996500393d28] __schedule at ffffffff9b6e6095 > #1 [ffff996500393db8] schedule at ffffffff9b6e64df > #2 [ffff996500393dc8] rwsem_down_read_slowpath at ffffffff9b6e9421 > #3 [ffff996500393e78] down_read_killable at ffffffff9b6e95e2 > #4 [ffff996500393e88] iterate_dir at ffffffff9b103c56 > #5 [ffff996500393ec8] ksys_getdents64 at ffffffff9b104b0c > torvalds#6 [ffff996500393f30] __x64_sys_getdents64 at ffffffff9b104bb6 > torvalds#7 [ffff996500393f38] do_syscall_64 at ffffffff9ae04315 > > in iterate_dir: > if (shared) > res = down_read_killable(&inode->i_rwsem); <<<< > else > res = down_write_killable(&inode->i_rwsem); > Reported-by: Frank Sorenson <[email protected]> Reviewed-by: Pavel Shilovsky <[email protected]> Signed-off-by: Ronnie Sahlberg <[email protected]> Signed-off-by: Steve French <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 5c9934b upstream. We got another syzbot report [1] that tells us we must use write_lock_irq()/write_unlock_irq() to avoid possible deadlock. [1] WARNING: inconsistent lock state 5.5.0-rc1-syzkaller #0 Not tainted -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-R} usage. syz-executor826/9605 [HC1[1]:SC0[0]:HE0:SE1] takes: ffffffff8a128718 (disc_data_lock){+-..}, at: sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138 {HARDIRQ-ON-W} state was registered at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline] _raw_write_lock_bh+0x33/0x50 kernel/locking/spinlock.c:319 sixpack_close+0x1d/0x250 drivers/net/hamradio/6pack.c:657 tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:489 tty_set_ldisc+0x230/0x6b0 drivers/tty/tty_ldisc.c:585 tiocsetd drivers/tty/tty_io.c:2337 [inline] tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2597 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe irq event stamp: 3946 hardirqs last enabled at (3945): [<ffffffff87c86e43>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (3945): [<ffffffff87c86e43>] _raw_spin_unlock_irq+0x23/0x80 kernel/locking/spinlock.c:199 hardirqs last disabled at (3946): [<ffffffff8100675f>] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42 softirqs last enabled at (2658): [<ffffffff86a8b4df>] spin_unlock_bh include/linux/spinlock.h:383 [inline] softirqs last enabled at (2658): [<ffffffff86a8b4df>] clusterip_netdev_event+0x46f/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:222 softirqs last disabled at (2656): [<ffffffff86a8b22b>] spin_lock_bh include/linux/spinlock.h:343 [inline] softirqs last disabled at (2656): [<ffffffff86a8b22b>] clusterip_netdev_event+0x1bb/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:196 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(disc_data_lock); <Interrupt> lock(disc_data_lock); *** DEADLOCK *** 5 locks held by syz-executor826/9605: #0: ffff8880a905e198 (&tty->legacy_mutex){+.+.}, at: tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19 #1: ffffffff899a56c0 (rcu_read_lock){....}, at: mutex_spin_on_owner+0x0/0x330 kernel/locking/mutex.c:413 #2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: serial8250_interrupt+0x2d/0x1a0 drivers/tty/serial/8250/8250_core.c:116 #3: ffffffff8c104048 (&port_lock_key){-.-.}, at: serial8250_handle_irq.part.0+0x24/0x330 drivers/tty/serial/8250/8250_port.c:1823 #4: ffff8880a905e090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref+0x22/0x90 drivers/tty/tty_ldisc.c:288 stack backtrace: CPU: 1 PID: 9605 Comm: syz-executor826 Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_usage_bug.cold+0x327/0x378 kernel/locking/lockdep.c:3101 valid_state kernel/locking/lockdep.c:3112 [inline] mark_lock_irq kernel/locking/lockdep.c:3309 [inline] mark_lock+0xbb4/0x1220 kernel/locking/lockdep.c:3666 mark_usage kernel/locking/lockdep.c:3554 [inline] __lock_acquire+0x1e55/0x4a00 kernel/locking/lockdep.c:3909 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x50 kernel/locking/spinlock.c:223 sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138 sixpack_write_wakeup+0x25/0x340 drivers/net/hamradio/6pack.c:402 tty_wakeup+0xe9/0x120 drivers/tty/tty_io.c:536 tty_port_default_wakeup+0x2b/0x40 drivers/tty/tty_port.c:50 tty_port_tty_wakeup+0x57/0x70 drivers/tty/tty_port.c:387 uart_write_wakeup+0x46/0x70 drivers/tty/serial/serial_core.c:104 serial8250_tx_chars+0x495/0xaf0 drivers/tty/serial/8250/8250_port.c:1761 serial8250_handle_irq.part.0+0x2a2/0x330 drivers/tty/serial/8250/8250_port.c:1834 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1820 [inline] serial8250_default_handle_irq+0xc0/0x150 drivers/tty/serial/8250/8250_port.c:1850 serial8250_interrupt+0xf1/0x1a0 drivers/tty/serial/8250/8250_core.c:126 __handle_irq_event_percpu+0x15d/0x970 kernel/irq/handle.c:149 handle_irq_event_percpu+0x74/0x160 kernel/irq/handle.c:189 handle_irq_event+0xa7/0x134 kernel/irq/handle.c:206 handle_edge_irq+0x25e/0x8d0 kernel/irq/chip.c:830 generic_handle_irq_desc include/linux/irqdesc.h:156 [inline] do_IRQ+0xde/0x280 arch/x86/kernel/irq.c:250 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:607 </IRQ> RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:685 [inline] RIP: 0010:mutex_spin_on_owner+0x247/0x330 kernel/locking/mutex.c:579 Code: c3 be 08 00 00 00 4c 89 e7 e8 e5 06 59 00 4c 89 e0 48 c1 e8 03 42 80 3c 38 00 0f 85 e1 00 00 00 49 8b 04 24 a8 01 75 96 f3 90 <e9> 2f fe ff ff 0f 0b e8 0d 19 09 00 84 c0 0f 85 ff fd ff ff 48 c7 RSP: 0018:ffffc90001eafa20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffd7 RAX: 0000000000000000 RBX: ffff88809fd9e0c0 RCX: 1ffffffff13266dd RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000 RBP: ffffc90001eafa60 R08: 1ffff11013d22898 R09: ffffed1013d22899 R10: ffffed1013d22898 R11: ffff88809e9144c7 R12: ffff8880a905e138 R13: ffff88809e9144c0 R14: 0000000000000000 R15: dffffc0000000000 mutex_optimistic_spin kernel/locking/mutex.c:673 [inline] __mutex_lock_common kernel/locking/mutex.c:962 [inline] __mutex_lock+0x32b/0x13c0 kernel/locking/mutex.c:1106 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121 tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19 tty_release+0xb5/0xe90 drivers/tty/tty_io.c:1665 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x8e7/0x2ef0 kernel/exit.c:797 do_group_exit+0x135/0x360 kernel/exit.c:895 __do_sys_exit_group kernel/exit.c:906 [inline] __se_sys_exit_group kernel/exit.c:904 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:904 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x43fef8 Code: Bad RIP value. RSP: 002b:00007ffdb07d2338 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fef8 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00000000004bf730 R08: 00000000000000e7 R09: ffffffffffffffd0 R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 Fixes: 6e4e2f8 ("6pack,mkiss: fix lock inconsistency") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: syzbot <[email protected]> Cc: Arnd Bergmann <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 5a9ef19 ] We would not be transmitting using the correct SYSTEMPORT transmit queue during ndo_select_queue() which looks up the internal TX ring map because while establishing the mapping we would be off by 4, so for instance, when we populate switch port mappings we would be doing: switch port 0, queue 0 -> ring index #0 switch port 0, queue 1 -> ring index #1 ... switch port 0, queue 3 -> ring index #3 switch port 1, queue 0 -> ring index torvalds#8 (4 + 4 * 1) ... instead of using ring index #4. This would cause our ndo_select_queue() to use the fallback queue mechanism which would pick up an incorrect ring for that switch port. Fix this by using the correct switch queue number instead of SYSTEMPORT queue number. Fixes: 25c4407 ("net: systemport: Simplify queue mapping logic") Signed-off-by: Florian Fainelli <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…s_blob() [ Upstream commit 12fe3dd ] Calling ceph_buffer_put() in __ceph_build_xattrs_blob() may result in freeing the i_xattrs.blob buffer while holding the i_ceph_lock. This can be fixed by having this function returning the old blob buffer and have the callers of this function freeing it when the lock is released. The following backtrace was triggered by fstests generic/117. BUG: sleeping function called from invalid context at mm/vmalloc.c:2283 in_atomic(): 1, irqs_disabled(): 0, pid: 649, name: fsstress 4 locks held by fsstress/649: #0: 00000000a7478e7e (&type->s_umount_key#19){++++}, at: iterate_supers+0x77/0xf0 #1: 00000000f8de1423 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: ceph_check_caps+0x7b/0xc60 #2: 00000000562f2b27 (&s->s_mutex){+.+.}, at: ceph_check_caps+0x3bd/0xc60 #3: 00000000f83ce16a (&mdsc->snap_rwsem){++++}, at: ceph_check_caps+0x3ed/0xc60 CPU: 1 PID: 649 Comm: fsstress Not tainted 5.2.0+ torvalds#439 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0x67/0x90 ___might_sleep.cold+0x9f/0xb1 vfree+0x4b/0x60 ceph_buffer_release+0x1b/0x60 __ceph_build_xattrs_blob+0x12b/0x170 __send_cap+0x302/0x540 ? __lock_acquire+0x23c/0x1e40 ? __mark_caps_flushing+0x15c/0x280 ? _raw_spin_unlock+0x24/0x30 ceph_check_caps+0x5f0/0xc60 ceph_flush_dirty_caps+0x7c/0x150 ? __ia32_sys_fdatasync+0x20/0x20 ceph_sync_fs+0x5a/0x130 iterate_supers+0x8f/0xf0 ksys_sync+0x4f/0xb0 __ia32_sys_sync+0xa/0x10 do_syscall_64+0x50/0x1c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fc6409ab617 Signed-off-by: Luis Henriques <[email protected]> Reviewed-by: Jeff Layton <[email protected]> Signed-off-by: Ilya Dryomov <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit af8a85a ] Calling ceph_buffer_put() in fill_inode() may result in freeing the i_xattrs.blob buffer while holding the i_ceph_lock. This can be fixed by postponing the call until later, when the lock is released. The following backtrace was triggered by fstests generic/070. BUG: sleeping function called from invalid context at mm/vmalloc.c:2283 in_atomic(): 1, irqs_disabled(): 0, pid: 3852, name: kworker/0:4 6 locks held by kworker/0:4/3852: #0: 000000004270f6bb ((wq_completion)ceph-msgr){+.+.}, at: process_one_work+0x1b8/0x5f0 #1: 00000000eb420803 ((work_completion)(&(&con->work)->work)){+.+.}, at: process_one_work+0x1b8/0x5f0 #2: 00000000be1c53a4 (&s->s_mutex){+.+.}, at: dispatch+0x288/0x1476 #3: 00000000559cb958 (&mdsc->snap_rwsem){++++}, at: dispatch+0x2eb/0x1476 #4: 000000000d5ebbae (&req->r_fill_mutex){+.+.}, at: dispatch+0x2fc/0x1476 #5: 00000000a83d0514 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: fill_inode.isra.0+0xf8/0xf70 CPU: 0 PID: 3852 Comm: kworker/0:4 Not tainted 5.2.0+ torvalds#441 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Workqueue: ceph-msgr ceph_con_workfn Call Trace: dump_stack+0x67/0x90 ___might_sleep.cold+0x9f/0xb1 vfree+0x4b/0x60 ceph_buffer_release+0x1b/0x60 fill_inode.isra.0+0xa9b/0xf70 ceph_fill_trace+0x13b/0xc70 ? dispatch+0x2eb/0x1476 dispatch+0x320/0x1476 ? __mutex_unlock_slowpath+0x4d/0x2a0 ceph_con_workfn+0xc97/0x2ec0 ? process_one_work+0x1b8/0x5f0 process_one_work+0x244/0x5f0 worker_thread+0x4d/0x3e0 kthread+0x105/0x140 ? process_one_work+0x5f0/0x5f0 ? kthread_park+0x90/0x90 ret_from_fork+0x3a/0x50 Signed-off-by: Luis Henriques <[email protected]> Reviewed-by: Jeff Layton <[email protected]> Signed-off-by: Ilya Dryomov <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 1dd9bc0 upstream. fs_context::user_ns is used by fuse_parse_param(), even during remount, so it needs to be set to the existing value for reconfigure. Reproducer: #include <fcntl.h> #include <sys/mount.h> int main() { char opts[128]; int fd = open("/dev/fuse", O_RDWR); sprintf(opts, "fd=%d,rootmode=040000,user_id=0,group_id=0", fd); mkdir("mnt", 0777); mount("foo", "mnt", "fuse.foo", 0, opts); mount("foo", "mnt", "fuse.foo", MS_REMOUNT, opts); } Crash: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 0 PID: 129 Comm: syz_make_kuid Not tainted 5.3.0-rc5-next-20190821 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014 RIP: 0010:map_id_range_down+0xb/0xc0 kernel/user_namespace.c:291 [...] Call Trace: map_id_down kernel/user_namespace.c:312 [inline] make_kuid+0xe/0x10 kernel/user_namespace.c:389 fuse_parse_param+0x116/0x210 fs/fuse/inode.c:523 vfs_parse_fs_param+0xdb/0x1b0 fs/fs_context.c:145 vfs_parse_fs_string+0x6a/0xa0 fs/fs_context.c:188 generic_parse_monolithic+0x85/0xc0 fs/fs_context.c:228 parse_monolithic_mount_data+0x1b/0x20 fs/fs_context.c:708 do_remount fs/namespace.c:2525 [inline] do_mount+0x39a/0xa60 fs/namespace.c:3107 ksys_mount+0x7d/0xd0 fs/namespace.c:3325 __do_sys_mount fs/namespace.c:3339 [inline] __se_sys_mount fs/namespace.c:3336 [inline] __x64_sys_mount+0x20/0x30 fs/namespace.c:3336 do_syscall_64+0x4a/0x1a0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reported-by: [email protected] Fixes: 408cbe6 ("vfs: Convert fuse to use the new mount API") Cc: David Howells <[email protected]> Cc: Miklos Szeredi <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Reviewed-by: David Howells <[email protected]> Signed-off-by: Al Viro <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…event An eventfd monitors multiple memory thresholds of the cgroup, closes them, the kernel deletes all events related to this eventfd. Before all events are deleted, another eventfd monitors the memory threshold of this cgroup, leading to a crash: BUG: kernel NULL pointer dereference, address: 0000000000000004 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 800000033058e067 P4D 800000033058e067 PUD 3355ce067 PMD 0 Oops: 0002 [#1] SMP PTI CPU: 2 PID: 14012 Comm: kworker/2:6 Kdump: loaded Not tainted 5.6.0-rc4 #3 Hardware name: LENOVO 20AWS01K00/20AWS01K00, BIOS GLET70WW (2.24 ) 05/21/2014 Workqueue: events memcg_event_remove RIP: 0010:__mem_cgroup_usage_unregister_event+0xb3/0x190 RSP: 0018:ffffb47e01c4fe18 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff8bb223a8a000 RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffff8bb22fb83540 RDI: 0000000000000001 RBP: ffffb47e01c4fe48 R08: 0000000000000000 R09: 0000000000000010 R10: 000000000000000c R11: 071c71c71c71c71c R12: ffff8bb226aba880 R13: ffff8bb223a8a480 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8bb242680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000004 CR3: 000000032c29c003 CR4: 00000000001606e0 Call Trace: memcg_event_remove+0x32/0x90 process_one_work+0x172/0x380 worker_thread+0x49/0x3f0 kthread+0xf8/0x130 ret_from_fork+0x35/0x40 CR2: 0000000000000004 We can reproduce this problem in the following ways: 1. We create a new cgroup subdirectory and a new eventfd, and then we monitor multiple memory thresholds of the cgroup through this eventfd. 2. closing this eventfd, and __mem_cgroup_usage_unregister_event () will be called multiple times to delete all events related to this eventfd. The first time __mem_cgroup_usage_unregister_event() is called, the kernel will clear all items related to this eventfd in thresholds-> primary. Since there is currently only one eventfd, thresholds-> primary becomes empty, so the kernel will set thresholds-> primary and hresholds-> spare to NULL. If at this time, the user creates a new eventfd and monitor the memory threshold of this cgroup, kernel will re-initialize thresholds-> primary. Then when __mem_cgroup_usage_unregister_event () is called for the second time, because thresholds-> primary is not empty, the system will access thresholds-> spare, but thresholds-> spare is NULL, which will trigger a crash. In general, the longer it takes to delete all events related to this eventfd, the easier it is to trigger this problem. The solution is to check whether the thresholds associated with the eventfd has been cleared when deleting the event. If so, we do nothing. [[email protected]: fix comment, per Kirill] Fixes: 907860e ("cgroups: make cftype.unregister_event() void-returning") Signed-off-by: Chunguang Xu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Acked-by: Michal Hocko <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Vladimir Davydov <[email protected]> Cc: <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>

[ Upstream commit d3296fb ] We hit following warning when running tests on kernel compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y: WARNING: CPU: 19 PID: 4472 at mm/gup.c:2381 __get_user_pages_fast+0x1a4/0x200 CPU: 19 PID: 4472 Comm: dummy Not tainted 5.6.0-rc6+ #3 RIP: 0010:__get_user_pages_fast+0x1a4/0x200 ... Call Trace: perf_prepare_sample+0xff1/0x1d90 perf_event_output_forward+0xe8/0x210 __perf_event_overflow+0x11a/0x310 __intel_pmu_pebs_event+0x657/0x850 intel_pmu_drain_pebs_nhm+0x7de/0x11d0 handle_pmi_common+0x1b2/0x650 intel_pmu_handle_irq+0x17b/0x370 perf_event_nmi_handler+0x40/0x60 nmi_handle+0x192/0x590 default_do_nmi+0x6d/0x150 do_nmi+0x2f9/0x3c0 nmi+0x8e/0xd7 While __get_user_pages_fast() is IRQ-safe, it calls access_ok(), which warns on: WARN_ON_ONCE(!in_task() && !pagefault_disabled()) Peter suggested disabling page faults around __get_user_pages_fast(), which gets rid of the warning in access_ok() call. Suggested-by: Peter Zijlstra <[email protected]> Signed-off-by: Jiri Olsa <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Sasha Levin <[email protected]>

commit 10a98cb upstream. Leaving PF_MEMALLOC set when exiting a kthread causes it to remain set during do_exit(). That can confuse things. In particular, if BSD process accounting is enabled, then do_exit() writes data to an accounting file. If that file has FS_SYNC_FL set, then this write occurs synchronously and can misbehave if PF_MEMALLOC is set. For example, if the accounting file is located on an XFS filesystem, then a WARN_ON_ONCE() in iomap_do_writepage() is triggered and the data doesn't get written when it should. Or if the accounting file is located on an ext4 filesystem without a journal, then a WARN_ON_ONCE() in ext4_write_inode() is triggered and the inode doesn't get written. Fix this in xfsaild() by using the helper functions to save and restore PF_MEMALLOC. This can be reproduced as follows in the kvm-xfstests test appliance modified to add the 'acct' Debian package, and with kvm-xfstests's recommended kconfig modified to add CONFIG_BSD_PROCESS_ACCT=y: mkfs.xfs -f /dev/vdb mount /vdb touch /vdb/file chattr +S /vdb/file accton /vdb/file mkfs.xfs -f /dev/vdc mount /vdc umount /vdc It causes: WARNING: CPU: 1 PID: 336 at fs/iomap/buffered-io.c:1534 CPU: 1 PID: 336 Comm: xfsaild/vdc Not tainted 5.6.0-rc5 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014 RIP: 0010:iomap_do_writepage+0x16b/0x1f0 fs/iomap/buffered-io.c:1534 [...] Call Trace: write_cache_pages+0x189/0x4d0 mm/page-writeback.c:2238 iomap_writepages+0x1c/0x33 fs/iomap/buffered-io.c:1642 xfs_vm_writepages+0x65/0x90 fs/xfs/xfs_aops.c:578 do_writepages+0x41/0xe0 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0xd2/0x120 mm/filemap.c:421 file_write_and_wait_range+0x71/0xc0 mm/filemap.c:760 xfs_file_fsync+0x7a/0x2b0 fs/xfs/xfs_file.c:114 generic_write_sync include/linux/fs.h:2867 [inline] xfs_file_buffered_aio_write+0x379/0x3b0 fs/xfs/xfs_file.c:691 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write+0x130/0x1d0 fs/read_write.c:483 __kernel_write+0x54/0xe0 fs/read_write.c:515 do_acct_process+0x122/0x170 kernel/acct.c:522 slow_acct_process kernel/acct.c:581 [inline] acct_process+0x1d4/0x27c kernel/acct.c:607 do_exit+0x83d/0xbc0 kernel/exit.c:791 kthread+0xf1/0x140 kernel/kthread.c:257 ret_from_fork+0x27/0x50 arch/x86/entry/entry_64.S:352 This bug was originally reported by syzbot at https://lore.kernel.org/r/[email protected]. Reported-by: [email protected] Signed-off-by: Eric Biggers <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…f fs_info::journal_info commit fcc9973 upstream. [BUG] One run of btrfs/063 triggered the following lockdep warning: ============================================ WARNING: possible recursive locking detected 5.6.0-rc7-custom+ torvalds#48 Not tainted -------------------------------------------- kworker/u24:0/7 is trying to acquire lock: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] but task is already holding lock: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sb_internal#2); lock(sb_internal#2); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/u24:0/7: #0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80 #1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80 #2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs] #3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs] stack backtrace: CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ torvalds#48 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] Call Trace: dump_stack+0xc2/0x11a __lock_acquire.cold+0xce/0x214 lock_acquire+0xe6/0x210 __sb_start_write+0x14e/0x290 start_transaction+0x66c/0x890 [btrfs] btrfs_join_transaction+0x1d/0x20 [btrfs] find_free_extent+0x1504/0x1a50 [btrfs] btrfs_reserve_extent+0xd5/0x1f0 [btrfs] btrfs_alloc_tree_block+0x1ac/0x570 [btrfs] btrfs_copy_root+0x213/0x580 [btrfs] create_reloc_root+0x3bd/0x470 [btrfs] btrfs_init_reloc_root+0x2d2/0x310 [btrfs] record_root_in_trans+0x191/0x1d0 [btrfs] btrfs_record_root_in_trans+0x90/0xd0 [btrfs] start_transaction+0x16e/0x890 [btrfs] btrfs_join_transaction+0x1d/0x20 [btrfs] btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs] finish_ordered_fn+0x15/0x20 [btrfs] btrfs_work_helper+0x116/0x9a0 [btrfs] process_one_work+0x632/0xb80 worker_thread+0x80/0x690 kthread+0x1a3/0x1f0 ret_from_fork+0x27/0x50 It's pretty hard to reproduce, only one hit so far. [CAUSE] This is because we're calling btrfs_join_transaction() without re-using the current running one: btrfs_finish_ordered_io() |- btrfs_join_transaction() <<< Call #1 |- btrfs_record_root_in_trans() |- btrfs_reserve_extent() |- btrfs_join_transaction() <<< Call #2 Normally such btrfs_join_transaction() call should re-use the existing one, without trying to re-start a transaction. But the problem is, in btrfs_join_transaction() call #1, we call btrfs_record_root_in_trans() before initializing current::journal_info. And in btrfs_join_transaction() call #2, we're relying on current::journal_info to avoid such deadlock. [FIX] Call btrfs_record_root_in_trans() after we have initialized current::journal_info. CC: [email protected] # 4.4+ Signed-off-by: Qu Wenruo <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 5cbf326 upstream. Use follow_pfn() to get the PFN of a PFNMAP VMA instead of assuming that vma->vm_pgoff holds the base PFN of the VMA. This fixes a bug where attempting to do VFIO_IOMMU_MAP_DMA on an arbitrary PFNMAP'd region of memory calculates garbage for the PFN. Hilariously, this only got detected because the first "PFN" calculated by vaddr_get_pfn() is PFN 0 (vma->vm_pgoff==0), and iommu_iova_to_phys() uses PA==0 as an error, which triggers a WARN in vfio_unmap_unpin() because the translation "failed". PFN 0 is now unconditionally reserved on x86 in order to mitigate L1TF, which causes is_invalid_reserved_pfn() to return true and in turns results in vaddr_get_pfn() returning success for PFN 0. Eventually the bogus calculation runs into PFNs that aren't reserved and leads to failure in vfio_pin_map_dma(). The subsequent call to vfio_remove_dma() attempts to unmap PFN 0 and WARNs. WARNING: CPU: 8 PID: 5130 at drivers/vfio/vfio_iommu_type1.c:750 vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1] Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio ... CPU: 8 PID: 5130 Comm: sgx Tainted: G W 5.6.0-rc5-705d787c7fee-vfio+ #3 Hardware name: Intel Corporation Mehlow UP Server Platform/Moss Beach Server, BIOS CNLSE2R1.D00.X119.B49.1803010910 03/01/2018 RIP: 0010:vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1] Code: <0f> 0b 49 81 c5 00 10 00 00 e9 c5 fe ff ff bb 00 10 00 00 e9 3d fe RSP: 0018:ffffbeb5039ebda8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff9a55cbf8d480 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a52b771c200 RBP: 0000000000000000 R08: 0000000000000040 R09: 00000000fffffff2 R10: 0000000000000001 R11: ffff9a51fa896000 R12: 0000000184010000 R13: 0000000184000000 R14: 0000000000010000 R15: ffff9a55cb66ea08 FS: 00007f15d3830b40(0000) GS:ffff9a55d5600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561cf39429e0 CR3: 000000084f75f005 CR4: 00000000003626e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vfio_remove_dma+0x17/0x70 [vfio_iommu_type1] vfio_iommu_type1_ioctl+0x9e3/0xa7b [vfio_iommu_type1] ksys_ioctl+0x92/0xb0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x4c/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f15d04c75d7 Code: <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 f7 d8 64 89 01 48 Fixes: 73fa0d1 ("vfio: Type1 IOMMU implementation") Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Alex Williamson <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

[ Upstream commit 20a785a ] This BUG halt was reported a while back, but the patch somehow got missed: PID: 2879 TASK: c16adaa0 CPU: 1 COMMAND: "sctpn" #0 [f418dd28] crash_kexec at c04a7d8c #1 [f418dd7c] oops_end at c0863e02 #2 [f418dd90] do_invalid_op at c040aaca #3 [f418de28] error_code (via invalid_op) at c08631a5 EAX: f34baac0 EBX: 00000090 ECX: f418deb0 EDX: f5542950 EBP: 00000000 DS: 007b ESI: f34ba800 ES: 007b EDI: f418dea0 GS: 00e0 CS: 0060 EIP: c046fa5e ERR: ffffffff EFLAGS: 00010286 #4 [f418de5c] add_timer at c046fa5e #5 [f418de68] sctp_do_sm at f8db8c77 [sctp] torvalds#6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp] torvalds#7 [f418df48] inet_shutdown at c080baf9 torvalds#8 [f418df5c] sys_shutdown at c079eedf torvalds#9 [f418df7] sys_socketcall at c079fe88 EAX: ffffffda EBX: 0000000d ECX: bfceea90 EDX: 0937af98 DS: 007b ESI: 0000000c ES: 007b EDI: b7150ae4 SS: 007b ESP: bfceea7c EBP: bfceeaa8 GS: 0033 CS: 0073 EIP: b775c424 ERR: 00000066 EFLAGS: 00000282 It appears that the side effect that starts the shutdown timer was processed multiple times, which can happen as multiple paths can trigger it. This of course leads to the BUG halt in add_timer getting called. Fix seems pretty straightforward, just check before the timer is added if its already been started. If it has mod the timer instead to min(current expiration, new expiration) Its been tested but not confirmed to fix the problem, as the issue has only occured in production environments where test kernels are enjoined from being installed. It appears to be a sane fix to me though. Also, recentely, Jere found a reproducer posted on list to confirm that this resolves the issues Signed-off-by: Neil Horman <[email protected]> CC: Vlad Yasevich <[email protected]> CC: "David S. Miller" <[email protected]> CC: [email protected] CC: [email protected] CC: [email protected] Acked-by: Marcelo Ricardo Leitner <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit 2b86cb8 upstream. Be there a platform with the following layout: Regular NIC | +----> DSA master for switch port | +----> DSA master for another switch port After changing DSA back to static lockdep class keys in commit 1a33e10 ("net: partially revert dynamic lockdep key changes"), this kernel splat can be seen: [ 13.361198] ============================================ [ 13.366524] WARNING: possible recursive locking detected [ 13.371851] 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988 Not tainted [ 13.377874] -------------------------------------------- [ 13.383201] swapper/0/0 is trying to acquire lock: [ 13.388004] ffff0000668ff298 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0 [ 13.397879] [ 13.397879] but task is already holding lock: [ 13.403727] ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0 [ 13.413593] [ 13.413593] other info that might help us debug this: [ 13.420140] Possible unsafe locking scenario: [ 13.420140] [ 13.426075] CPU0 [ 13.428523] ---- [ 13.430969] lock(&dsa_slave_netdev_xmit_lock_key); [ 13.435946] lock(&dsa_slave_netdev_xmit_lock_key); [ 13.440924] [ 13.440924] *** DEADLOCK *** [ 13.440924] [ 13.446860] May be due to missing lock nesting notation [ 13.446860] [ 13.453668] 6 locks held by swapper/0/0: [ 13.457598] #0: ffff800010003de0 ((&idev->mc_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x0/0x400 [ 13.466593] #1: ffffd4d3fb478700 (rcu_read_lock){....}-{1:2}, at: mld_sendpack+0x0/0x560 [ 13.474803] #2: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x64/0xb10 [ 13.483886] #3: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0 [ 13.492793] #4: ffff0000661a1698 (&dsa_slave_netdev_xmit_lock_key){+.-.}-{2:2}, at: __dev_queue_xmit+0x84c/0xbe0 [ 13.503094] #5: ffffd4d3fb478728 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x6c/0xbe0 [ 13.512000] [ 13.512000] stack backtrace: [ 13.516369] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc4-02121-gc32a05ecd7af-dirty #988 [ 13.530421] Call trace: [ 13.532871] dump_backtrace+0x0/0x1d8 [ 13.536539] show_stack+0x24/0x30 [ 13.539862] dump_stack+0xe8/0x150 [ 13.543271] __lock_acquire+0x1030/0x1678 [ 13.547290] lock_acquire+0xf8/0x458 [ 13.550873] _raw_spin_lock+0x44/0x58 [ 13.554543] __dev_queue_xmit+0x84c/0xbe0 [ 13.558562] dev_queue_xmit+0x24/0x30 [ 13.562232] dsa_slave_xmit+0xe0/0x128 [ 13.565988] dev_hard_start_xmit+0xf4/0x448 [ 13.570182] __dev_queue_xmit+0x808/0xbe0 [ 13.574200] dev_queue_xmit+0x24/0x30 [ 13.577869] neigh_resolve_output+0x15c/0x220 [ 13.582237] ip6_finish_output2+0x244/0xb10 [ 13.586430] __ip6_finish_output+0x1dc/0x298 [ 13.590709] ip6_output+0x84/0x358 [ 13.594116] mld_sendpack+0x2bc/0x560 [ 13.597786] mld_ifc_timer_expire+0x210/0x390 [ 13.602153] call_timer_fn+0xcc/0x400 [ 13.605822] run_timer_softirq+0x588/0x6e0 [ 13.609927] __do_softirq+0x118/0x590 [ 13.613597] irq_exit+0x13c/0x148 [ 13.616918] __handle_domain_irq+0x6c/0xc0 [ 13.621023] gic_handle_irq+0x6c/0x160 [ 13.624779] el1_irq+0xbc/0x180 [ 13.627927] cpuidle_enter_state+0xb4/0x4d0 [ 13.632120] cpuidle_enter+0x3c/0x50 [ 13.635703] call_cpuidle+0x44/0x78 [ 13.639199] do_idle+0x228/0x2c8 [ 13.642433] cpu_startup_entry+0x2c/0x48 [ 13.646363] rest_init+0x1ac/0x280 [ 13.649773] arch_call_rest_init+0x14/0x1c [ 13.653878] start_kernel+0x490/0x4bc Lockdep keys themselves were added in commit ab92d68 ("net: core: add generic lockdep keys"), and it's very likely that this splat existed since then, but I have no real way to check, since this stacked platform wasn't supported by mainline back then. >From Taehee's own words: This patch was considered that all stackable devices have LLTX flag. But the dsa doesn't have LLTX, so this splat happened. After this patch, dsa shares the same lockdep class key. On the nested dsa interface architecture, which you illustrated, the same lockdep class key will be used in __dev_queue_xmit() because dsa doesn't have LLTX. So that lockdep detects deadlock because the same lockdep class key is used recursively although actually the different locks are used. There are some ways to fix this problem. 1. using NETIF_F_LLTX flag. If possible, using the LLTX flag is a very clear way for it. But I'm so sorry I don't know whether the dsa could have LLTX or not. 2. using dynamic lockdep again. It means that each interface uses a separate lockdep class key. So, lockdep will not detect recursive locking. But this way has a problem that it could consume lockdep class key too many. Currently, lockdep can have 8192 lockdep class keys. - you can see this number with the following command. cat /proc/lockdep_stats lock-classes: 1251 [max: 8192] ... The [max: 8192] means that the maximum number of lockdep class keys. If too many lockdep class keys are registered, lockdep stops to work. So, using a dynamic(separated) lockdep class key should be considered carefully. In addition, updating lockdep class key routine might have to be existing. (lockdep_register_key(), lockdep_set_class(), lockdep_unregister_key()) 3. Using lockdep subclass. A lockdep class key could have 8 subclasses. The different subclass is considered different locks by lockdep infrastructure. But "lock-classes" is not counted by subclasses. So, it could avoid stopping lockdep infrastructure by an overflow of lockdep class keys. This approach should also have an updating lockdep class key routine. (lockdep_set_subclass()) 4. Using nonvalidate lockdep class key. The lockdep infrastructure supports nonvalidate lockdep class key type. It means this lockdep is not validated by lockdep infrastructure. So, the splat will not happen but lockdep couldn't detect real deadlock case because lockdep really doesn't validate it. I think this should be used for really special cases. (lockdep_set_novalidate_class()) Further discussion here: https://patchwork.ozlabs.org/project/netdev/patch/[email protected]/ There appears to be no negative side-effect to declaring lockless TX for the DSA virtual interfaces, which means they handle their own locking. So that's what we do to make the splat go away. Patch tested in a wide variety of cases: unicast, multicast, PTP, etc. Fixes: ab92d68 ("net: core: add generic lockdep keys") Suggested-by: Taehee Yoo <[email protected]> Signed-off-by: Vladimir Oltean <[email protected]> Reviewed-by: Florian Fainelli <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

cl_glimpse_lock() doesn't match a lock with LDLM_FL_BL_AST even if this lock is acquired by the same thread earlier. It needs only size to check for spare file, so let't add LDLM_FL_CBPENDING to match flags. #1 [ffff9ba7326036f0] schedule at ffffffff87b67c49 #2 [ffff9ba732603700] obd_get_request_slot at ffffffffc0dbe0a4 [obdclass] #3 [ffff9ba7326037b8] ldlm_cli_enqueue at ffffffffc0faedce [ptlrpc] #4 [ffff9ba732603878] mdc_enqueue_send at ffffffffc11b38a8 [mdc] #5 [ffff9ba732603938] mdc_lock_enqueue at ffffffffc11b3eb2 [mdc] torvalds#6 [ffff9ba7326039a8] cl_lock_enqueue at ffffffffc0dfee95 [obdclass] torvalds#7 [ffff9ba7326039e0] lov_lock_enqueue at ffffffffc10ef265 [lov] torvalds#8 [ffff9ba732603a20] cl_lock_enqueue at ffffffffc0dfee95 [obdclass] torvalds#9 [ffff9ba732603a58] cl_lock_request at ffffffffc0dff54b [obdclass] HPE-bug-id: LUS-8690 WC-bug-id: https://jira.whamcloud.com/browse/LU-13987 Lustre-commit: 829a3a93d43e ("LU-13987 ldlm: Don't re-enqueue glimpse lock on read") Signed-off-by: Andriy Skulysh <[email protected]> Reviewed-by: Vitaly Fertman <[email protected]> Reviewed-by: Alexander Boyko <[email protected]> Reviewed-by: Andrew Perepechko <[email protected]> Reviewed-on: https://review.whamcloud.com/40044 Reviewed-by: Alexander Boyko <[email protected]> Reviewed-by: Vitaly Fertman <[email protected]> Reviewed-by: Oleg Drokin <[email protected]> Signed-off-by: NeilBrown <[email protected]>

Prarit reported that depending on the affinity setting the ' irq $N: Affinity broken due to vector space exhaustion.' message is showing up in dmesg, but the vector space on the CPUs in the affinity mask is definitely not exhausted. Shung-Hsi provided traces and analysis which pinpoints the problem: The ordering of trying to assign an interrupt vector in assign_irq_vector_any_locked() is simply wrong if the interrupt data has a valid node assigned. It does: 1) Try the intersection of affinity mask and node mask 2) Try the node mask 3) Try the full affinity mask 4) Try the full online mask Obviously #2 and #3 are in the wrong order as the requested affinity mask has to take precedence. In the observed cases #1 failed because the affinity mask did not contain CPUs from node 0. That made it allocate a vector from node 0, thereby breaking affinity and emitting the misleading message. Revert the order of #2 and #3 so the full affinity mask without the node intersection is tried before actually affinity is broken. If no node is assigned then only the full affinity mask and if that fails the full online mask is tried. Fixes: d6ffc6a ("x86/vector: Respect affinity mask in irq descriptor") Reported-by: Prarit Bhargava <[email protected]> Reported-by: Shung-Hsi Yu <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Shung-Hsi Yu <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected]

commit ff083a2 upstream. Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily, all paths that read perf_guest_cbs already require RCU protection, e.g. to protect the callback chains, so only the direct perf_guest_cbs touchpoints need to be modified. Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure perf_guest_cbs isn't reloaded between a !NULL check and a dereference. Fixed via the READ_ONCE() in rcu_dereference(). Bug #2 is that on weakly-ordered architectures, updates to the callbacks themselves are not guaranteed to be visible before the pointer is made visible to readers. Fixed by the smp_store_release() in rcu_assign_pointer() when the new pointer is non-NULL. Bug #3 is that, because the callbacks are global, it's possible for readers to run in parallel with an unregisters, and thus a module implementing the callbacks can be unloaded while readers are in flight, resulting in a use-after-free. Fixed by a synchronize_rcu() call when unregistering callbacks. Bug #1 escaped notice because it's extremely unlikely a compiler will reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest() guard all but guarantees the consumer will win the race, e.g. to nullify perf_guest_cbs, KVM has to completely exit the guest and teardown down all VMs before KVM start its module unload / unregister sequence. This also makes it all but impossible to encounter bug #3. Bug #2 has not been a problem because all architectures that register callbacks are strongly ordered and/or have a static set of callbacks. But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming kvm_intel module load/unload leads to: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ torvalds#459 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:perf_misc_flags+0x1c/0x70 Call Trace: perf_prepare_sample+0x53/0x6b0 perf_event_output_forward+0x67/0x160 __perf_event_overflow+0x52/0xf0 handle_pmi_common+0x207/0x300 intel_pmu_handle_irq+0xcf/0x410 perf_event_nmi_handler+0x28/0x50 nmi_handle+0xc7/0x260 default_do_nmi+0x6b/0x170 exc_nmi+0x103/0x130 asm_exc_nmi+0x76/0xbf Fixes: 39447b3 ("perf: Enhance perf to allow for guest statistic collection from host") Signed-off-by: Sean Christopherson <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Paolo Bonzini <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>

…_work [ Upstream commit ed05c7c ] When enable debug config, it print below warning while shut down wlan interface shuh as run "ifconfig wlan0 down". The reason is because ar->regd_update_work is ran once, and it is will call wiphy_lock(ar->hw->wiphy) in function ath11k_regd_update() which is running in workqueue of ieee80211_local queued by ieee80211_queue_work(). Another thread from "ifconfig wlan0 down" will also accuqire the lock by wiphy_lock(sdata->local->hw.wiphy) in function ieee80211_stop(), and then it call ieee80211_stop_device() to flush_workqueue(local->workqueue), this will wait the workqueue of ieee80211_local finished. Then deadlock will happen easily if the two thread run meanwhile. Below warning disappeared after this change. [ 914.088798] ath11k_pci 0000:05:00.0: mac remove interface (vdev 0) [ 914.088806] ath11k_pci 0000:05:00.0: mac stop 11d scan [ 914.088810] ath11k_pci 0000:05:00.0: mac stop 11d vdev id 0 [ 914.088827] ath11k_pci 0000:05:00.0: htc ep 2 consumed 1 credits (total 0) [ 914.088841] ath11k_pci 0000:05:00.0: send 11d scan stop vdev id 0 [ 914.088849] ath11k_pci 0000:05:00.0: htc insufficient credits ep 2 required 1 available 0 [ 914.088856] ath11k_pci 0000:05:00.0: htc insufficient credits ep 2 required 1 available 0 [ 914.096434] ath11k_pci 0000:05:00.0: rx ce pipe 2 len 16 [ 914.096442] ath11k_pci 0000:05:00.0: htc ep 2 got 1 credits (total 1) [ 914.096481] ath11k_pci 0000:05:00.0: htc ep 2 consumed 1 credits (total 0) [ 914.096491] ath11k_pci 0000:05:00.0: WMI vdev delete id 0 [ 914.111598] ath11k_pci 0000:05:00.0: rx ce pipe 2 len 16 [ 914.111628] ath11k_pci 0000:05:00.0: htc ep 2 got 1 credits (total 1) [ 914.114659] ath11k_pci 0000:05:00.0: rx ce pipe 2 len 20 [ 914.114742] ath11k_pci 0000:05:00.0: htc rx completion ep 2 skb pK-error [ 914.115977] ath11k_pci 0000:05:00.0: vdev delete resp for vdev id 0 [ 914.116685] ath11k_pci 0000:05:00.0: vdev 00:03:7f:29:61:11 deleted, vdev_id 0 [ 914.117583] ====================================================== [ 914.117592] WARNING: possible circular locking dependency detected [ 914.117600] 5.16.0-rc1-wt-ath+ #1 Tainted: G OE [ 914.117611] ------------------------------------------------------ [ 914.117618] ifconfig/2805 is trying to acquire lock: [ 914.117628] ffff9c00a62bb548 ((wq_completion)phy0){+.+.}-{0:0}, at: flush_workqueue+0x87/0x470 [ 914.117674] but task is already holding lock: [ 914.117682] ffff9c00baea07d0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_stop+0x38/0x180 [mac80211] [ 914.117872] which lock already depends on the new lock. [ 914.117880] the existing dependency chain (in reverse order) is: [ 914.117888] -> #3 (&rdev->wiphy.mtx){+.+.}-{4:4}: [ 914.117910] __mutex_lock+0xa0/0x9c0 [ 914.117930] mutex_lock_nested+0x1b/0x20 [ 914.117944] reg_process_self_managed_hints+0x3a/0xb0 [cfg80211] [ 914.118093] wiphy_regulatory_register+0x47/0x80 [cfg80211] [ 914.118229] wiphy_register+0x84f/0x9c0 [cfg80211] [ 914.118353] ieee80211_register_hw+0x6b1/0xd90 [mac80211] [ 914.118486] ath11k_mac_register+0x6af/0xb60 [ath11k] [ 914.118550] ath11k_core_qmi_firmware_ready+0x383/0x4a0 [ath11k] [ 914.118598] ath11k_qmi_driver_event_work+0x347/0x4a0 [ath11k] [ 914.118656] process_one_work+0x228/0x670 [ 914.118669] worker_thread+0x4d/0x440 [ 914.118680] kthread+0x16d/0x1b0 [ 914.118697] ret_from_fork+0x22/0x30 [ 914.118714] -> #2 (rtnl_mutex){+.+.}-{4:4}: [ 914.118736] __mutex_lock+0xa0/0x9c0 [ 914.118751] mutex_lock_nested+0x1b/0x20 [ 914.118767] rtnl_lock+0x17/0x20 [ 914.118783] ath11k_regd_update+0x15a/0x260 [ath11k] [ 914.118841] ath11k_regd_update_work+0x15/0x20 [ath11k] [ 914.118897] process_one_work+0x228/0x670 [ 914.118909] worker_thread+0x4d/0x440 [ 914.118920] kthread+0x16d/0x1b0 [ 914.118934] ret_from_fork+0x22/0x30 [ 914.118948] -> #1 ((work_completion)(&ar->regd_update_work)){+.+.}-{0:0}: [ 914.118972] process_one_work+0x1fa/0x670 [ 914.118984] worker_thread+0x4d/0x440 [ 914.118996] kthread+0x16d/0x1b0 [ 914.119010] ret_from_fork+0x22/0x30 [ 914.119023] -> #0 ((wq_completion)phy0){+.+.}-{0:0}: [ 914.119045] __lock_acquire+0x146d/0x1cf0 [ 914.119057] lock_acquire+0x19b/0x360 [ 914.119067] flush_workqueue+0xae/0x470 [ 914.119084] ieee80211_stop_device+0x3b/0x50 [mac80211] [ 914.119260] ieee80211_do_stop+0x5d7/0x830 [mac80211] [ 914.119409] ieee80211_stop+0x45/0x180 [mac80211] [ 914.119557] __dev_close_many+0xb3/0x120 [ 914.119573] __dev_change_flags+0xc3/0x1d0 [ 914.119590] dev_change_flags+0x29/0x70 [ 914.119605] devinet_ioctl+0x653/0x810 [ 914.119620] inet_ioctl+0x193/0x1e0 [ 914.119631] sock_do_ioctl+0x4d/0xf0 [ 914.119649] sock_ioctl+0x262/0x340 [ 914.119665] __x64_sys_ioctl+0x96/0xd0 [ 914.119678] do_syscall_64+0x3d/0xd0 [ 914.119694] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 914.119709] other info that might help us debug this: [ 914.119717] Chain exists of: (wq_completion)phy0 --> rtnl_mutex --> &rdev->wiphy.mtx [ 914.119745] Possible unsafe locking scenario: [ 914.119752] CPU0 CPU1 [ 914.119758] ---- ---- [ 914.119765] lock(&rdev->wiphy.mtx); [ 914.119778] lock(rtnl_mutex); [ 914.119792] lock(&rdev->wiphy.mtx); [ 914.119807] lock((wq_completion)phy0); [ 914.119819] *** DEADLOCK *** [ 914.119827] 2 locks held by ifconfig/2805: [ 914.119837] #0: ffffffffba3dc010 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x17/0x20 [ 914.119872] #1: ffff9c00baea07d0 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_stop+0x38/0x180 [mac80211] [ 914.120039] stack backtrace: [ 914.120048] CPU: 0 PID: 2805 Comm: ifconfig Tainted: G OE 5.16.0-rc1-wt-ath+ #1 [ 914.120064] Hardware name: LENOVO 418065C/418065C, BIOS 83ET63WW (1.33 ) 07/29/2011 [ 914.120074] Call Trace: [ 914.120084] <TASK> [ 914.120094] dump_stack_lvl+0x73/0xa4 [ 914.120119] dump_stack+0x10/0x12 [ 914.120135] print_circular_bug.isra.44+0x221/0x2e0 [ 914.120165] check_noncircular+0x106/0x150 [ 914.120203] __lock_acquire+0x146d/0x1cf0 [ 914.120215] ? __lock_acquire+0x146d/0x1cf0 [ 914.120245] lock_acquire+0x19b/0x360 [ 914.120259] ? flush_workqueue+0x87/0x470 [ 914.120286] ? lockdep_init_map_type+0x6b/0x250 [ 914.120310] flush_workqueue+0xae/0x470 [ 914.120327] ? flush_workqueue+0x87/0x470 [ 914.120344] ? lockdep_hardirqs_on+0xd7/0x150 [ 914.120391] ieee80211_stop_device+0x3b/0x50 [mac80211] [ 914.120565] ? ieee80211_stop_device+0x3b/0x50 [mac80211] [ 914.120736] ieee80211_do_stop+0x5d7/0x830 [mac80211] [ 914.120906] ieee80211_stop+0x45/0x180 [mac80211] [ 914.121060] __dev_close_many+0xb3/0x120 [ 914.121081] __dev_change_flags+0xc3/0x1d0 [ 914.121109] dev_change_flags+0x29/0x70 [ 914.121131] devinet_ioctl+0x653/0x810 [ 914.121149] ? __might_fault+0x77/0x80 [ 914.121179] inet_ioctl+0x193/0x1e0 [ 914.121194] ? inet_ioctl+0x193/0x1e0 [ 914.121218] ? __might_fault+0x77/0x80 [ 914.121238] ? _copy_to_user+0x68/0x80 [ 914.121266] sock_do_ioctl+0x4d/0xf0 [ 914.121283] ? inet_stream_connect+0x60/0x60 [ 914.121297] ? sock_do_ioctl+0x4d/0xf0 [ 914.121329] sock_ioctl+0x262/0x340 [ 914.121347] ? sock_ioctl+0x262/0x340 [ 914.121362] ? exit_to_user_mode_prepare+0x13b/0x280 [ 914.121388] ? syscall_enter_from_user_mode+0x20/0x50 [ 914.121416] __x64_sys_ioctl+0x96/0xd0 [ 914.121430] ? br_ioctl_call+0x90/0x90 [ 914.121445] ? __x64_sys_ioctl+0x96/0xd0 [ 914.121465] do_syscall_64+0x3d/0xd0 [ 914.121482] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 914.121497] RIP: 0033:0x7f0ed051737b [ 914.121513] Code: 0f 1e fa 48 8b 05 15 3b 0d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e5 3a 0d 00 f7 d8 64 89 01 48 [ 914.121527] RSP: 002b:00007fff7be38b98 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 914.121544] RAX: ffffffffffffffda RBX: 00007fff7be38ba0 RCX: 00007f0ed051737b [ 914.121555] RDX: 00007fff7be38ba0 RSI: 0000000000008914 RDI: 0000000000000004 [ 914.121566] RBP: 00007fff7be38c60 R08: 000000000000000a R09: 0000000000000001 [ 914.121576] R10: 0000000000000000 R11: 0000000000000202 R12: 00000000fffffffe [ 914.121586] R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000 [ 914.121620] </TASK> Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1 Signed-off-by: Wen Gong <[email protected]> Signed-off-by: Kalle Valo <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sasha Levin <[email protected]>

commit e804861 upstream. Quota disable ioctl starts a transaction before waiting for the qgroup rescan worker completes. However, this wait can be infinite and results in deadlock because of circular dependency among the quota disable ioctl, the qgroup rescan worker and the other task with transaction such as block group relocation task. The deadlock happens with the steps following: 1) Task A calls ioctl to disable quota. It starts a transaction and waits for qgroup rescan worker completes. 2) Task B such as block group relocation task starts a transaction and joins to the transaction that task A started. Then task B commits to the transaction. In this commit, task B waits for a commit by task A. 3) Task C as the qgroup rescan worker starts its job and starts a transaction. In this transaction start, task C waits for completion of the transaction that task A started and task B committed. This deadlock was found with fstests test case btrfs/115 and a zoned null_blk device. The test case enables and disables quota, and the block group reclaim was triggered during the quota disable by chance. The deadlock was also observed by running quota enable and disable in parallel with 'btrfs balance' command on regular null_blk devices. An example report of the deadlock: [372.469894] INFO: task kworker/u16:6:103 blocked for more than 122 seconds. [372.479944] Not tainted 5.16.0-rc8 torvalds#7 [372.485067] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.493898] task:kworker/u16:6 state:D stack: 0 pid: 103 ppid: 2 flags:0x00004000 [372.503285] Workqueue: btrfs-qgroup-rescan btrfs_work_helper [btrfs] [372.510782] Call Trace: [372.514092] <TASK> [372.521684] __schedule+0xb56/0x4850 [372.530104] ? io_schedule_timeout+0x190/0x190 [372.538842] ? lockdep_hardirqs_on+0x7e/0x100 [372.547092] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.555591] schedule+0xe0/0x270 [372.561894] btrfs_commit_transaction+0x18bb/0x2610 [btrfs] [372.570506] ? btrfs_apply_pending_changes+0x50/0x50 [btrfs] [372.578875] ? free_unref_page+0x3f2/0x650 [372.585484] ? finish_wait+0x270/0x270 [372.591594] ? release_extent_buffer+0x224/0x420 [btrfs] [372.599264] btrfs_qgroup_rescan_worker+0xc13/0x10c0 [btrfs] [372.607157] ? lock_release+0x3a9/0x6d0 [372.613054] ? btrfs_qgroup_account_extent+0xda0/0xda0 [btrfs] [372.620960] ? do_raw_spin_lock+0x11e/0x250 [372.627137] ? rwlock_bug.part.0+0x90/0x90 [372.633215] ? lock_is_held_type+0xe4/0x140 [372.639404] btrfs_work_helper+0x1ae/0xa90 [btrfs] [372.646268] process_one_work+0x7e9/0x1320 [372.652321] ? lock_release+0x6d0/0x6d0 [372.658081] ? pwq_dec_nr_in_flight+0x230/0x230 [372.664513] ? rwlock_bug.part.0+0x90/0x90 [372.670529] worker_thread+0x59e/0xf90 [372.676172] ? process_one_work+0x1320/0x1320 [372.682440] kthread+0x3b9/0x490 [372.687550] ? _raw_spin_unlock_irq+0x24/0x50 [372.693811] ? set_kthread_struct+0x100/0x100 [372.700052] ret_from_fork+0x22/0x30 [372.705517] </TASK> [372.709747] INFO: task btrfs-transacti:2347 blocked for more than 123 seconds. [372.729827] Not tainted 5.16.0-rc8 torvalds#7 [372.745907] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.767106] task:btrfs-transacti state:D stack: 0 pid: 2347 ppid: 2 flags:0x00004000 [372.787776] Call Trace: [372.801652] <TASK> [372.812961] __schedule+0xb56/0x4850 [372.830011] ? io_schedule_timeout+0x190/0x190 [372.852547] ? lockdep_hardirqs_on+0x7e/0x100 [372.871761] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.886792] schedule+0xe0/0x270 [372.901685] wait_current_trans+0x22c/0x310 [btrfs] [372.919743] ? btrfs_put_transaction+0x3d0/0x3d0 [btrfs] [372.938923] ? finish_wait+0x270/0x270 [372.959085] ? join_transaction+0xc75/0xe30 [btrfs] [372.977706] start_transaction+0x938/0x10a0 [btrfs] [372.997168] transaction_kthread+0x19d/0x3c0 [btrfs] [373.013021] ? btrfs_cleanup_transaction.isra.0+0xfc0/0xfc0 [btrfs] [373.031678] kthread+0x3b9/0x490 [373.047420] ? _raw_spin_unlock_irq+0x24/0x50 [373.064645] ? set_kthread_struct+0x100/0x100 [373.078571] ret_from_fork+0x22/0x30 [373.091197] </TASK> [373.105611] INFO: task btrfs:3145 blocked for more than 123 seconds. [373.114147] Not tainted 5.16.0-rc8 torvalds#7 [373.120401] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [373.130393] task:btrfs state:D stack: 0 pid: 3145 ppid: 3141 flags:0x00004000 [373.140998] Call Trace: [373.145501] <TASK> [373.149654] __schedule+0xb56/0x4850 [373.155306] ? io_schedule_timeout+0x190/0x190 [373.161965] ? lockdep_hardirqs_on+0x7e/0x100 [373.168469] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [373.175468] schedule+0xe0/0x270 [373.180814] wait_for_commit+0x104/0x150 [btrfs] [373.187643] ? test_and_set_bit+0x20/0x20 [btrfs] [373.194772] ? kmem_cache_free+0x124/0x550 [373.201191] ? btrfs_put_transaction+0x69/0x3d0 [btrfs] [373.208738] ? finish_wait+0x270/0x270 [373.214704] ? __btrfs_end_transaction+0x347/0x7b0 [btrfs] [373.222342] btrfs_commit_transaction+0x44d/0x2610 [btrfs] [373.230233] ? join_transaction+0x255/0xe30 [btrfs] [373.237334] ? btrfs_record_root_in_trans+0x4d/0x170 [btrfs] [373.245251] ? btrfs_apply_pending_changes+0x50/0x50 [btrfs] [373.253296] relocate_block_group+0x105/0xc20 [btrfs] [373.260533] ? mutex_lock_io_nested+0x1270/0x1270 [373.267516] ? btrfs_wait_nocow_writers+0x85/0x180 [btrfs] [373.275155] ? merge_reloc_roots+0x710/0x710 [btrfs] [373.283602] ? btrfs_wait_ordered_extents+0xd30/0xd30 [btrfs] [373.291934] ? kmem_cache_free+0x124/0x550 [373.298180] btrfs_relocate_block_group+0x35c/0x930 [btrfs] [373.306047] btrfs_relocate_chunk+0x85/0x210 [btrfs] [373.313229] btrfs_balance+0x12f4/0x2d20 [btrfs] [373.320227] ? lock_release+0x3a9/0x6d0 [373.326206] ? btrfs_relocate_chunk+0x210/0x210 [btrfs] [373.333591] ? lock_is_held_type+0xe4/0x140 [373.340031] ? rcu_read_lock_sched_held+0x3f/0x70 [373.346910] btrfs_ioctl_balance+0x548/0x700 [btrfs] [373.354207] btrfs_ioctl+0x7f2/0x71b0 [btrfs] [373.360774] ? lockdep_hardirqs_on_prepare+0x410/0x410 [373.367957] ? lockdep_hardirqs_on_prepare+0x410/0x410 [373.375327] ? btrfs_ioctl_get_supported_features+0x20/0x20 [btrfs] [373.383841] ? find_held_lock+0x2c/0x110 [373.389993] ? lock_release+0x3a9/0x6d0 [373.395828] ? mntput_no_expire+0xf7/0xad0 [373.402083] ? lock_is_held_type+0xe4/0x140 [373.408249] ? vfs_fileattr_set+0x9f0/0x9f0 [373.414486] ? selinux_file_ioctl+0x349/0x4e0 [373.420938] ? trace_raw_output_lock+0xb4/0xe0 [373.427442] ? selinux_inode_getsecctx+0x80/0x80 [373.434224] ? lockdep_hardirqs_on+0x7e/0x100 [373.440660] ? force_qs_rnp+0x2a0/0x6b0 [373.446534] ? lock_is_held_type+0x9b/0x140 [373.452763] ? __blkcg_punt_bio_submit+0x1b0/0x1b0 [373.459732] ? security_file_ioctl+0x50/0x90 [373.466089] __x64_sys_ioctl+0x127/0x190 [373.472022] do_syscall_64+0x3b/0x90 [373.477513] entry_SYSCALL_64_after_hwframe+0x44/0xae [373.484823] RIP: 0033:0x7f8f4af7e2bb [373.490493] RSP: 002b:00007ffcbf936178 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [373.500197] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f8f4af7e2bb [373.509451] RDX: 00007ffcbf936220 RSI: 00000000c4009420 RDI: 0000000000000003 [373.518659] RBP: 00007ffcbf93774a R08: 0000000000000013 R09: 00007f8f4b02d4e0 [373.527872] R10: 00007f8f4ae87740 R11: 0000000000000246 R12: 0000000000000001 [373.537222] R13: 00007ffcbf936220 R14: 0000000000000000 R15: 0000000000000002 [373.546506] </TASK> [373.550878] INFO: task btrfs:3146 blocked for more than 123 seconds. [373.559383] Not tainted 5.16.0-rc8 torvalds#7 [373.565748] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [373.575748] task:btrfs state:D stack: 0 pid: 3146 ppid: 2168 flags:0x00000000 [373.586314] Call Trace: [373.590846] <TASK> [373.595121] __schedule+0xb56/0x4850 [373.600901] ? __lock_acquire+0x23db/0x5030 [373.607176] ? io_schedule_timeout+0x190/0x190 [373.613954] schedule+0xe0/0x270 [373.619157] schedule_timeout+0x168/0x220 [373.625170] ? usleep_range_state+0x150/0x150 [373.631653] ? mark_held_locks+0x9e/0xe0 [373.637767] ? do_raw_spin_lock+0x11e/0x250 [373.643993] ? lockdep_hardirqs_on_prepare+0x17b/0x410 [373.651267] ? _raw_spin_unlock_irq+0x24/0x50 [373.657677] ? lockdep_hardirqs_on+0x7e/0x100 [373.664103] wait_for_completion+0x163/0x250 [373.670437] ? bit_wait_timeout+0x160/0x160 [373.676585] btrfs_quota_disable+0x176/0x9a0 [btrfs] [373.683979] ? btrfs_quota_enable+0x12f0/0x12f0 [btrfs] [373.691340] ? down_write+0xd0/0x130 [373.696880] ? down_write_killable+0x150/0x150 [373.703352] btrfs_ioctl+0x3945/0x71b0 [btrfs] [373.710061] ? find_held_lock+0x2c/0x110 [373.716192] ? lock_release+0x3a9/0x6d0 [373.722047] ? __handle_mm_fault+0x23cd/0x3050 [373.728486] ? btrfs_ioctl_get_supported_features+0x20/0x20 [btrfs] [373.737032] ? set_pte+0x6a/0x90 [373.742271] ? do_raw_spin_unlock+0x55/0x1f0 [373.748506] ? lock_is_held_type+0xe4/0x140 [373.754792] ? vfs_fileattr_set+0x9f0/0x9f0 [373.761083] ? selinux_file_ioctl+0x349/0x4e0 [373.767521] ? selinux_inode_getsecctx+0x80/0x80 [373.774247] ? __up_read+0x182/0x6e0 [373.780026] ? count_memcg_events.constprop.0+0x46/0x60 [373.787281] ? up_write+0x460/0x460 [373.792932] ? security_file_ioctl+0x50/0x90 [373.799232] __x64_sys_ioctl+0x127/0x190 [373.805237] do_syscall_64+0x3b/0x90 [373.810947] entry_SYSCALL_64_after_hwframe+0x44/0xae [373.818102] RIP: 0033:0x7f1383ea02bb [373.823847] RSP: 002b:00007fffeb4d71f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [373.833641] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1383ea02bb [373.842961] RDX: 00007fffeb4d7210 RSI: 00000000c0109428 RDI: 0000000000000003 [373.852179] RBP: 0000000000000003 R08: 0000000000000003 R09: 0000000000000078 [373.861408] R10: 00007f1383daec78 R11: 0000000000000202 R12: 00007fffeb4d874a [373.870647] R13: 0000000000493099 R14: 0000000000000001 R15: 0000000000000000 [373.879838] </TASK> [373.884018] Showing all locks held in the system: [373.894250] 3 locks held by kworker/4:1/58: [373.900356] 1 lock held by khungtaskd/63: [373.906333] #0: ffffffff8945ff60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 [373.917307] 3 locks held by kworker/u16:6/103: [373.923938] #0: ffff888127b4f138 ((wq_completion)btrfs-qgroup-rescan){+.+.}-{0:0}, at: process_one_work+0x712/0x1320 [373.936555] #1: ffff88810b817dd8 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work+0x73f/0x1320 [373.951109] #2: ffff888102dd4650 (sb_internal#2){.+.+}-{0:0}, at: btrfs_qgroup_rescan_worker+0x1f6/0x10c0 [btrfs] [373.964027] 2 locks held by less/1803: [373.969982] #0: ffff88813ed56098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 [373.981295] #1: ffffc90000b3b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x9e2/0x1060 [373.992969] 1 lock held by btrfs-transacti/2347: [373.999893] #0: ffff88813d4887a8 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0xe3/0x3c0 [btrfs] [374.015872] 3 locks held by btrfs/3145: [374.022298] #0: ffff888102dd4460 (sb_writers#18){.+.+}-{0:0}, at: btrfs_ioctl_balance+0xc3/0x700 [btrfs] [374.034456] #1: ffff88813d48a0a0 (&fs_info->reclaim_bgs_lock){+.+.}-{3:3}, at: btrfs_balance+0xfe5/0x2d20 [btrfs] [374.047646] #2: ffff88813d488838 (&fs_info->cleaner_mutex){+.+.}-{3:3}, at: btrfs_relocate_block_group+0x354/0x930 [btrfs] [374.063295] 4 locks held by btrfs/3146: [374.069647] #0: ffff888102dd4460 (sb_writers#18){.+.+}-{0:0}, at: btrfs_ioctl+0x38b1/0x71b0 [btrfs] [374.081601] #1: ffff88813d488bb8 (&fs_info->subvol_sem){+.+.}-{3:3}, at: btrfs_ioctl+0x38fd/0x71b0 [btrfs] [374.094283] #2: ffff888102dd4650 (sb_internal#2){.+.+}-{0:0}, at: btrfs_quota_disable+0xc8/0x9a0 [btrfs] [374.106885] #3: ffff88813d489800 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_disable+0xd5/0x9a0 [btrfs] [374.126780] ============================================= To avoid the deadlock, wait for the qgroup rescan worker to complete before starting the transaction for the quota disable ioctl. Clear BTRFS_FS_QUOTA_ENABLE flag before the wait and the transaction to request the worker to complete. On transaction start failure, set the BTRFS_FS_QUOTA_ENABLE flag again. These BTRFS_FS_QUOTA_ENABLE flag changes can be done safely since the function btrfs_quota_disable is not called concurrently because of fs_info->subvol_sem. Also check the BTRFS_FS_QUOTA_ENABLE flag in qgroup_rescan_init to avoid another qgroup rescan worker to start after the previous qgroup worker completed. CC: [email protected] # 5.4+ Suggested-by: Nikolay Borisov <[email protected]> Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Shin'ichiro Kawasaki <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit fb5222a upstream. Patch series "page table check fixes and cleanups", v5. This patch (of 4): The pte entry that is used in pte_advanced_tests() is never removed from the page table at the end of the test. The issue is detected by page_table_check, to repro compile kernel with the following configs: CONFIG_DEBUG_VM_PGTABLE=y CONFIG_PAGE_TABLE_CHECK=y CONFIG_PAGE_TABLE_CHECK_ENFORCED=y During the boot the following BUG is printed: debug_vm_pgtable: [debug_vm_pgtable ]: Validating architecture page table helpers ------------[ cut here ]------------ kernel BUG at mm/page_table_check.c:162! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.16.0-11413-g2c271fe77d52 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 ... The entry should be properly removed from the page table before the page is released to the free list. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Fixes: a5c3b9f ("mm/debug_vm_pgtable: add tests validating advanced arch page table helpers") Signed-off-by: Pasha Tatashin <[email protected]> Reviewed-by: Zi Yan <[email protected]> Tested-by: Zi Yan <[email protected]> Acked-by: David Rientjes <[email protected]> Reviewed-by: Anshuman Khandual <[email protected]> Cc: Paul Turner <[email protected]> Cc: Wei Xu <[email protected]> Cc: Greg Thelen <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Will Deacon <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Dave Hansen <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Aneesh Kumar K.V <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Muchun Song <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: <[email protected]> [5.9+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Henry von Tresckow added 4 commits May 14, 2018 21:49

Initial Commit to support GB-PC2

2a26d5f

- Add gbpc2.dts based on GB-PC2.dts from https://gogs.librecmc.org/ldpinney/GnuBee-libreCMC - add config DTB_GNUBEE2 opttion to Kconfig - add gnubee2_defconfig

Enable Task accounting for Iotop

1214165

Enable Kexec system call for booting other kernels without flashing

5b3a917

Add additional LED triggers:

d1a3416

Aded onshot,disk,heartbeat and cpu triggers for system LEDs

neilbrown merged commit 093cb5a into neilbrown:gnubee/v4.15 Jun 6, 2018

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Gnubee/v4.15 #3

Gnubee/v4.15 #3

hvontres commented May 15, 2018

neilbrown commented Jun 6, 2018

hvontres commented Jun 6, 2018 via email

Gnubee/v4.15 #3

Gnubee/v4.15 #3

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hvontres commented May 15, 2018

neilbrown commented Jun 6, 2018

hvontres commented Jun 6, 2018 via email