diff options
| author | Jan Beulich <JBeulich@suse.com> | 2014-02-27 08:47:02 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-05-06 07:59:26 -0700 |
| commit | f88b98a743b5a59ff49b2e289009d00eff7d7c26 (patch) | |
| tree | e50d5c949969db54a84e0a4bbda7b4661623956a /arch | |
| parent | 7f37f259e30d6230e06d43363b2cbbd9658f0f59 (diff) | |
x86, hash: Fix build failure with older binutils
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 <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/530F0996020000780011FBE7@nat28.tlf.novell.com
Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Thomas Graf <tgraf@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/lib/hash.c | 4 |
2 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index eeda43abed6..f8842c44456 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -152,6 +152,7 @@ cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTI # 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) diff --git a/arch/x86/lib/hash.c b/arch/x86/lib/hash.c index 3056702e81f..060cc4415bd 100644 --- 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; } |