Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fix from Thomas Gleixner:
 "rt_mutex_futex_unlock() grew a new irq-off call site, but the function
  assumes that its always called from irq enabled context.

  Use (un)lock_irqsafe() to handle the new call site correctly"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rtmutex: Make rt_mutex_futex_unlock() safe for irq-off callsites

1 files changed, 3 insertions, 2 deletions

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 65cc0cb984e6..940633c63254 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1616,11 +1616,12 @@ bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
 void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
 {
         DEFINE_WAKE_Q(wake_q);
+        unsigned long flags;
         bool postunlock;
 
-        raw_spin_lock_irq(&lock->wait_lock);
+        raw_spin_lock_irqsave(&lock->wait_lock, flags);
         postunlock = __rt_mutex_futex_unlock(lock, &wake_q);
-        raw_spin_unlock_irq(&lock->wait_lock);
+        raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
 
         if (postunlock)
                 rt_mutex_postunlock(&wake_q);