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-rw-r--r--kernel/futex.c18
1 files changed, 15 insertions, 3 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index 4949d33..5c88839 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1791,6 +1791,7 @@ static int futex_wait(u32 __user *uaddr, int fshared,
current->timer_slack_ns);
}
+retry:
/* Prepare to wait on uaddr. */
ret = futex_wait_setup(uaddr, val, fshared, &q, &hb);
if (ret)
@@ -1808,9 +1809,14 @@ static int futex_wait(u32 __user *uaddr, int fshared,
goto out_put_key;
/*
- * We expect signal_pending(current), but another thread may
- * have handled it for us already.
+ * We expect signal_pending(current), but we might be the
+ * victim of a spurious wakeup as well.
*/
+ if (!signal_pending(current)) {
+ put_futex_key(fshared, &q.key);
+ goto retry;
+ }
+
ret = -ERESTARTSYS;
if (!abs_time)
goto out_put_key;
@@ -2118,9 +2124,11 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
*/
plist_del(&q->list, &q->list.plist);
+ /* Handle spurious wakeups gracefully */
+ ret = -EAGAIN;
if (timeout && !timeout->task)
ret = -ETIMEDOUT;
- else
+ else if (signal_pending(current))
ret = -ERESTARTNOINTR;
}
return ret;
@@ -2198,6 +2206,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
debug_rt_mutex_init_waiter(&rt_waiter);
rt_waiter.task = NULL;
+retry:
key2 = FUTEX_KEY_INIT;
ret = get_futex_key(uaddr2, fshared, &key2, VERIFY_WRITE);
if (unlikely(ret != 0))
@@ -2292,6 +2301,9 @@ out_put_keys:
out_key2:
put_futex_key(fshared, &key2);
+ /* Spurious wakeup ? */
+ if (ret == -EAGAIN)
+ goto retry;
out:
if (to) {
hrtimer_cancel(&to->timer);
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