diff options
| author | Jeremy Fitzhardinge <jeremy@goop.org> | 2012-04-02 16:15:33 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-22 15:38:59 -0700 |
| commit | 36f87c5f10a44a44d1c1d9111c043d965295ab44 (patch) | |
| tree | abac1416a69fdc7f66a12d7becd217bde218ba47 | |
| parent | a10c8741cf87142f6eb835c0adac649ffa34767e (diff) | |
x86: Use correct byte-sized register constraint in __xchg_op()
commit 2ca052a3710fac208eee690faefdeb8bbd4586a1 upstream.
x86-64 can access the low half of any register, but i386 can only do
it with a subset of registers. 'r' causes compilation failures on i386,
but 'q' expresses the constraint properly.
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Link: http://lkml.kernel.org/r/4F7A3315.501@goop.org
Reported-by: Leigh Scott <leigh123linux@googlemail.com>
Tested-by: Thomas Reitmayr <treitmayr@devbase.at>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/include/asm/cmpxchg.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h index b3b73326290..bc18d0ed459 100644 --- a/arch/x86/include/asm/cmpxchg.h +++ b/arch/x86/include/asm/cmpxchg.h @@ -43,7 +43,7 @@ extern void __add_wrong_size(void) switch (sizeof(*(ptr))) { \ case __X86_CASE_B: \ asm volatile (lock #op "b %b0, %1\n" \ - : "+r" (__ret), "+m" (*(ptr)) \ + : "+q" (__ret), "+m" (*(ptr)) \ : : "memory", "cc"); \ break; \ case __X86_CASE_W: \ |