linux/tools/objtool
Josh Poimboeuf 3c1f05835c objtool: Add Clang support
Since the ORC unwinder was made the default on x86_64, Clang-built
defconfig kernels have triggered some new objtool warnings:

  drivers/gpu/drm/i915/i915_gpu_error.o: warning: objtool: i915_error_printf()+0x6c: return with modified stack frame
  drivers/gpu/drm/i915/intel_display.o: warning: objtool: pipe_config_err()+0xa6: return with modified stack frame

The problem is that objtool has never seen clang-built binaries before.

Shockingly enough, objtool is apparently able to follow the code flow
mostly fine, except for one instruction sequence.  Instead of a LEAVE
instruction, clang restores RSP and RBP the long way:

   67c:   48 89 ec                mov    %rbp,%rsp
   67f:   5d                      pop    %rbp

Teach objtool about this new code sequence.

Reported-and-test-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fce88ce81c356eedcae7f00ed349cfaddb3363cc.1521741586.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27 08:21:29 +02:00
..
arch/x86 objtool: Fix Clang enum conversion warning 2017-12-28 13:11:13 +01:00
Documentation x86/asm: Fix inline asm call constraints for Clang 2017-09-23 15:06:20 +02:00
.gitignore objtool: Move synced files to their original relative locations 2017-11-07 10:48:23 +01:00
arch.h objtool: Assume unannotated UD2 instructions are dead ends 2017-07-28 08:33:32 +02:00
Build objtool: Add ORC unwind table generation 2017-07-18 10:57:43 +02:00
builtin-check.c objtool: Add module specific retpoline rules 2018-02-21 09:05:05 +01:00
builtin-orc.c objtool: Use existing global variables for options 2018-02-21 09:05:04 +01:00
builtin.h objtool: Add module specific retpoline rules 2018-02-21 09:05:05 +01:00
cfi.h objtool: Handle GCC stack pointer adjustment bug 2017-08-30 10:48:41 +02:00
check.c objtool: Add Clang support 2018-03-27 08:21:29 +02:00
check.h objtool: Add retpoline validation 2018-02-21 09:05:04 +01:00
elf.c objtool: Improve error message for bad file argument 2018-01-16 01:27:27 +01:00
elf.h objtool: Add ORC unwind table generation 2017-07-18 10:57:43 +02:00
Makefile tools/objtool/Makefile: don't assume sync-check.sh is executable 2018-01-13 10:42:48 -08:00
objtool.c objtool: Print top level commands on incorrect usage 2017-10-18 15:22:26 +02:00
orc_dump.c objtool: Fix 64-bit build on 32-bit host 2017-12-06 22:38:14 +01:00
orc_gen.c objtool: Warn on stripped section symbol 2018-01-30 15:09:23 +01:00
orc.h objtool: Move synced files to their original relative locations 2017-11-07 10:48:23 +01:00
special.c objtool: Implement stack validation 2.0 2017-06-30 10:19:19 +02:00
special.h
sync-check.sh objtool: Move kernel headers/code sync check to a script 2017-11-07 10:48:34 +01:00
warn.h objtool: Implement stack validation 2.0 2017-06-30 10:19:19 +02:00