From: Josh Poimboeuf Date: Tue, 25 Jul 2017 14:44:51 +0000 (-0500) Subject: x86/asm: Make objtool unreachable macros independent from GCC version X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=1ee6f00d1164955b7bdadd36fc0f2736754784d9;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git x86/asm: Make objtool unreachable macros independent from GCC version The ASM_UNREACHABLE macro isn't GCC version-specific, so move it outside the GCC 4.5+ check. Otherwise the 0-day robot will report objtool warnings for uses of ASM_UNREACHABLE with GCC 4.4. Also move the annotate_unreachable() macro so the related macros can stay together. Reported-by: kbuild test robot Signed-off-by: Josh Poimboeuf Cc: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: aa5d1b81500e ("x86/asm: Add ASM_UNREACHABLE") Link: http://lkml.kernel.org/r/fb18337dbf230fd36450d9faf19a2b2533dbcba1.1500993873.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 179375b2d862..17cbe3cffc0e 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -128,6 +128,22 @@ #define __always_unused __attribute__((unused)) #define __mode(x) __attribute__((mode(x))) +#ifdef CONFIG_STACK_VALIDATION +#define annotate_unreachable() ({ \ + asm("%c0:\n\t" \ + ".pushsection .discard.unreachable\n\t" \ + ".long %c0b - .\n\t" \ + ".popsection\n\t" : : "i" (__LINE__)); \ +}) +#define ASM_UNREACHABLE \ + "999:\n\t" \ + ".pushsection .discard.unreachable\n\t" \ + ".long 999b - .\n\t" \ + ".popsection\n\t" +#else +#define annotate_unreachable() +#endif + /* gcc version specific checks */ #if GCC_VERSION < 30200 @@ -201,22 +217,6 @@ #endif #endif -#ifdef CONFIG_STACK_VALIDATION -#define annotate_unreachable() ({ \ - asm("%c0:\n\t" \ - ".pushsection .discard.unreachable\n\t" \ - ".long %c0b - .\n\t" \ - ".popsection\n\t" : : "i" (__LINE__)); \ -}) -#define ASM_UNREACHABLE \ - "999:\n\t" \ - ".pushsection .discard.unreachable\n\t" \ - ".long 999b - .\n\t" \ - ".popsection\n\t" -#else -#define annotate_unreachable() -#endif - /* * Mark a position in code as unreachable. This can be used to * suppress control flow warnings after asm blocks that transfer