[PATCH] x86: fix atomic64_xxx_cx8() functions
From: Eric Dumazet <hidden>
Date: 2012-01-03 16:35:46
Also in:
lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
It appears about all functions in arch/x86/lib/atomic64_cx8_32.S are wrong in case cmpxchg8b must be restarted, because LOCK_PREFIX macro defines a label "1" clashing with other local labels : 1: some_instructions LOCK_PREFIX cmpxchg8b (%ebp) jne 1b / jumps to beginning of LOCK_PREFIX ! A possible fix is to use a magic label "672" in LOCK_PREFIX asm definition, similar to the "671" one we defined in LOCK_PREFIX_HERE. Signed-off-by: Eric Dumazet <redacted> Acked-by: Jan Beulich <redacted> CC: Christoph Lameter <redacted> CC: Ingo Molnar <redacted> CC: H. Peter Anvin <hpa@zytor.com> Cc: stable@vger.kernel.org [2.6.35+] --- arch/x86/include/asm/alternative-asm.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h
index 091508b..952bd01 100644
--- a/arch/x86/include/asm/alternative-asm.h
+++ b/arch/x86/include/asm/alternative-asm.h@@ -4,10 +4,10 @@ #ifdef CONFIG_SMP .macro LOCK_PREFIX -1: lock +672: lock .section .smp_locks,"a" .balign 4 - .long 1b - . + .long 672b - . .previous .endm #else