-stable review patch. If anyone has any objections, please let us know.
------------------
From: David Miller <[email protected]>
I copied the logic from ll/sc arch implementations, but that
was wrong and makes no sense at all. Just do a straight
compare-exchange instruction, just like x86.
Based upon bug reports from Dennis Gilmore and Fabio Massimo.
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
include/asm-sparc64/futex.h | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
--- linux-2.6.18.2.orig/include/asm-sparc64/futex.h
+++ linux-2.6.18.2/include/asm-sparc64/futex.h
@@ -87,24 +87,22 @@ static inline int
futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
{
__asm__ __volatile__(
- "\n1: lduwa [%2] %%asi, %0\n"
- "2: casa [%2] %%asi, %0, %1\n"
- "3:\n"
+ "\n1: casa [%3] %%asi, %2, %0\n"
+ "2:\n"
" .section .fixup,#alloc,#execinstr\n"
" .align 4\n"
- "4: ba 3b\n"
- " mov %3, %0\n"
+ "3: ba 2b\n"
+ " mov %4, %0\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
- " .word 1b, 4b\n"
- " .word 2b, 4b\n"
+ " .word 1b, 3b\n"
" .previous\n"
- : "=&r" (oldval)
- : "r" (newval), "r" (uaddr), "i" (-EFAULT)
+ : "=r" (newval)
+ : "0" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
: "memory");
- return oldval;
+ return newval;
}
#endif /* !(_SPARC64_FUTEX_H) */
--