diff options
| author | Ingo Molnar <mingo@elte.hu> | 2007-03-16 13:38:31 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-03-23 12:49:23 -0700 |
| commit | 120d6d2e32028348c630abb1aa4a68a83dfe6d8e (patch) | |
| tree | 0f91aab962512de1d66b9893505b4726850ab38e | |
| parent | 2e84657dbb433207cac7edfa45f755c8312fb15b (diff) | |
futex: PI state locking fix
Testing of -rt by IBM uncovered a locking bug in wake_futex_pi(): the PI
state needs to be locked before we access it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | kernel/futex.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 5a737de857d3..1df411e6be33 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -565,6 +565,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this) if (!pi_state) return -EINVAL; + spin_lock(&pi_state->pi_mutex.wait_lock); new_owner = rt_mutex_next_owner(&pi_state->pi_mutex); /* @@ -604,6 +605,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this) pi_state->owner = new_owner; spin_unlock_irq(&new_owner->pi_lock); + spin_unlock(&pi_state->pi_mutex.wait_lock); rt_mutex_unlock(&pi_state->pi_mutex); return 0; |