arm64: extable: sort the exception table at build time

As is done for other architectures, sort the exception table at build-time rather than during boot. Since sortextable appears to be a standalone C program relying on the host elf.h to provide EM_AARCH64, I've had to add a conditional check in order to allow cross-compilation on machines that aren't running a bleeding-edge libc-dev. Signed-off-by: Will Deacon <[email protected]> Signed-off-by: Catalin Marinas <[email protected]>
torvalds · Jun 12, 2013 · adace89 · adace89
1 parent 73150c9
commit adace89
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Showing 3 changed files with 7 additions and 9 deletions.
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
@@ -7,6 +7,7 @@ config ARM64
  select ARM_AMBA
  select ARM_ARCH_TIMER
  select ARM_GIC
+ select BUILDTIME_EXTABLE_SORT
  select CLONE_BACKWARDS
  select COMMON_CLK
  select GENERIC_CLOCKEVENTS

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
@@ -56,7 +56,7 @@ SECTIONS
  }
 
  RO_DATA(PAGE_SIZE)
-
+ EXCEPTION_TABLE(8)
  _etext = .; /* End of text and rodata section */
 
  . = ALIGN(PAGE_SIZE);
@@ -98,14 +98,6 @@ SECTIONS
  CACHELINE_ALIGNED_DATA(64)
  READ_MOSTLY_DATA(64)
 
- /*
- * The exception fixup table (might need resorting at runtime)
- */
- . = ALIGN(32);
- __start___ex_table = .;
- *(__ex_table)
- __stop___ex_table = .;
-
  /*
  * and the usual data section
  */

diff --git a/scripts/sortextable.c b/scripts/sortextable.c
@@ -31,6 +31,10 @@
 #include <tools/be_byteshift.h>
 #include <tools/le_byteshift.h>
 
+#ifndef EM_AARCH64
+#define EM_AARCH64 183
+#endif
+
 static int fd_map; /* File descriptor for file being modified. */
 static int mmap_failed; /* Boolean flag. */
 static void *ehdr_curr; /* current ElfXX_Ehdr * for resource cleanup */
@@ -249,6 +253,7 @@ do_file(char const *const fname)
  custom_sort = sort_relative_table;
  break;
  case EM_ARM:
+ case EM_AARCH64:
  case EM_MIPS:
  break;
  } /* end switch */