xtensa: fix futex_atomic_cmpxchg_inatomic
Return 0 if the operation was successful, not the userspace memory value. Check that userspace value equals passed oldval, not itself. Don't update *uval if the value wasn't read from userspace memory. This fixes process hang due to infinite loop in futex_lock_pi. It also fixes a bunch of glibc tests nptl/tst-mutexpi*. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
parent
32bb954dbf
commit
ca47480921
|
@ -92,7 +92,6 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
|
||||||
u32 oldval, u32 newval)
|
u32 oldval, u32 newval)
|
||||||
{
|
{
|
||||||
int ret = 0;
|
int ret = 0;
|
||||||
u32 prev;
|
|
||||||
|
|
||||||
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
|
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
|
||||||
return -EFAULT;
|
return -EFAULT;
|
||||||
|
@ -103,26 +102,24 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
|
||||||
|
|
||||||
__asm__ __volatile__ (
|
__asm__ __volatile__ (
|
||||||
" # futex_atomic_cmpxchg_inatomic\n"
|
" # futex_atomic_cmpxchg_inatomic\n"
|
||||||
"1: l32i %1, %3, 0\n"
|
" wsr %5, scompare1\n"
|
||||||
" mov %0, %5\n"
|
"1: s32c1i %1, %4, 0\n"
|
||||||
" wsr %1, scompare1\n"
|
" s32i %1, %6, 0\n"
|
||||||
"2: s32c1i %0, %3, 0\n"
|
"2:\n"
|
||||||
"3:\n"
|
|
||||||
" .section .fixup,\"ax\"\n"
|
" .section .fixup,\"ax\"\n"
|
||||||
" .align 4\n"
|
" .align 4\n"
|
||||||
"4: .long 3b\n"
|
"3: .long 2b\n"
|
||||||
"5: l32r %1, 4b\n"
|
"4: l32r %1, 3b\n"
|
||||||
" movi %0, %6\n"
|
" movi %0, %7\n"
|
||||||
" jx %1\n"
|
" jx %1\n"
|
||||||
" .previous\n"
|
" .previous\n"
|
||||||
" .section __ex_table,\"a\"\n"
|
" .section __ex_table,\"a\"\n"
|
||||||
" .long 1b,5b,2b,5b\n"
|
" .long 1b,4b\n"
|
||||||
" .previous\n"
|
" .previous\n"
|
||||||
: "+r" (ret), "=&r" (prev), "+m" (*uaddr)
|
: "+r" (ret), "+r" (newval), "+m" (*uaddr), "+m" (*uval)
|
||||||
: "r" (uaddr), "r" (oldval), "r" (newval), "I" (-EFAULT)
|
: "r" (uaddr), "r" (oldval), "r" (uval), "I" (-EFAULT)
|
||||||
: "memory");
|
: "memory");
|
||||||
|
|
||||||
*uval = prev;
|
|
||||||
return ret;
|
return ret;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue