On Mon, 2007-03-12 at 10:13 +0100, Ingo Molnar wrote: > Subject: [patch] futex: PI state locking fix > From: Ingo Molnar <[EMAIL PROTECTED]> > > testing of -rt by IBM uncovered a locking bug in wake_futex_pi(): the PI > state needs to be locked before we access it. > > this patch has been tested in -rt. Must-have for v2.6.21. > > Signed-off-by: Ingo Molnar <[EMAIL PROTECTED]>
Acked-by: Thomas Gleixner <[EMAIL PROTECTED]> > -- > kernel/futex.c | 2 ++ > 1 file changed, 2 insertions(+) > > Index: linux/kernel/futex.c > =================================================================== > --- linux.orig/kernel/futex.c > +++ linux/kernel/futex.c > @@ -566,6 +566,7 @@ static int wake_futex_pi(u32 __user *uad > if (!pi_state) > return -EINVAL; > > + spin_lock(&pi_state->pi_mutex.wait_lock); > new_owner = rt_mutex_next_owner(&pi_state->pi_mutex); > > /* > @@ -605,6 +606,7 @@ static int wake_futex_pi(u32 __user *uad > 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; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
