objtool: Fix '-mtune=atom' decoding support in objtool 2.0
authorJosh Poimboeuf <jpoimboe@redhat.com>
Thu, 27 Jul 2017 20:56:55 +0000 (15:56 -0500)
committerIngo Molnar <mingo@kernel.org>
Mon, 21 Aug 2017 14:07:27 +0000 (16:07 +0200)
commitdeecd4d71b12626db48544faa66bb897e2cafd07
treefb351bffbae38eec99a99b63bec7a2c3039d172d
parent14ccee78fc82f5512908f4424f541549a5705b89
objtool: Fix '-mtune=atom' decoding support in objtool 2.0

With '-mtune=atom', which is enabled with CONFIG_MATOM=y, GCC uses some
unusual instructions for setting up the stack.

Instead of:

  mov %rsp, %rbp

it does:

  lea (%rsp), %rbp

And instead of:

  add imm, %rsp

it does:

  lea disp(%rsp), %rsp

Add support for these instructions to the objtool decoder.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: baa41469a7b9 ("objtool: Implement stack validation 2.0")
Link: http://lkml.kernel.org/r/4ea1db896e821226efe1f8e09f270771bde47e65.1501188854.git.jpoimboe@redhat.com
[ This is a cherry-picked version of upcoming commit 5b8de48e82ba. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
tools/objtool/arch/x86/decode.c