diff options
Diffstat (limited to 'kernel/futex/pi.c')
| -rw-r--r-- | kernel/futex/pi.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/kernel/futex/pi.c b/kernel/futex/pi.c index 90e5197f4e56..5722467f2737 100644 --- a/kernel/futex/pi.c +++ b/kernel/futex/pi.c @@ -1135,6 +1135,7 @@ retry: hb = futex_hash(&key); spin_lock(&hb->lock); +retry_hb: /* * Check waiters first. We do not trust user space values at @@ -1177,12 +1178,17 @@ retry: /* * Futex vs rt_mutex waiter state -- if there are no rt_mutex * waiters even though futex thinks there are, then the waiter - * is leaving and the uncontended path is safe to take. + * is leaving. The entry needs to be removed from the list so a + * new futex_lock_pi() is not using this stale PI-state while + * the futex is available in user space again. + * There can be more than one task on its way out so it needs + * to retry. */ rt_waiter = rt_mutex_top_waiter(&pi_state->pi_mutex); if (!rt_waiter) { + __futex_unqueue(top_waiter); raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); - goto do_uncontended; + goto retry_hb; } get_pi_state(pi_state); @@ -1217,7 +1223,6 @@ retry: return ret; } -do_uncontended: /* * We have no kernel internal state, i.e. no waiters in the * kernel. Waiters which are about to queue themselves are stuck |