3.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jan Beulich <[email protected]> commit 06325190bd577e11429444d54f454b9d13f560c9 upstream. Just like for other ISA extension instruction uses we should check whether the assembler actually supports them. The fallback here simply is to encode an instruction with fixed operands (%eax and %ecx). [ hpa: tagging for -stable as a build fix ] Signed-off-by: Jan Beulich <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Cc: Francesco Fusco <[email protected]> Cc: Thomas Graf <[email protected]> Cc: David S. Miller <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: H. Peter Anvin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/Makefile | 1 + arch/x86/lib/hash.c | 4 ++++ 2 files changed, 5 insertions(+) --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -152,6 +152,7 @@ cfi-sections := $(call as-instr,.cfi_sec # does binutils support specific instructions? asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1) +asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1) avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1) avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1) --- a/arch/x86/lib/hash.c +++ b/arch/x86/lib/hash.c @@ -39,7 +39,11 @@ static inline u32 crc32_u32(u32 crc, u32 val) { +#ifdef CONFIG_AS_CRC32 asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val)); +#else + asm (".byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1" : "+a" (crc) : "c" (val)); +#endif return crc; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
