diff options
| author | Will Deacon <will.deacon@arm.com> | 2013-08-12 18:03:26 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-03-23 21:38:13 -0700 |
| commit | 9400319cc170bec3ff02f0adcb978552682725af (patch) | |
| tree | 0793ee1cf60f6f62b408f04aa66fb3145708e1b7 /arch | |
| parent | 5184c0b7c349f6783986d1848a5f1cdf333075b1 (diff) | |
ARM: 7811/1: locks: use early clobber in arch_spin_trylock
commit afa31d8eb86fc2f25083e675d57ac8173a98f999 upstream.
The res variable is written before we've finished with the input
operands (namely the lock address), so ensure that we mark it as `early
clobber' to avoid unintended register sharing.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/include/asm/spinlock.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index dd64cc6f9cb..b07c09e5a0a 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h @@ -107,7 +107,7 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock) " subs %1, %0, %0, ror #16\n" " addeq %0, %0, %4\n" " strexeq %2, %0, [%3]" - : "=&r" (slock), "=&r" (contended), "=r" (res) + : "=&r" (slock), "=&r" (contended), "=&r" (res) : "r" (&lock->slock), "I" (1 << TICKET_SHIFT) : "cc"); } while (res); |