KVM: selftests: test KVM_GET_SUPPORTED_HV_CPUID as a system ioctl

[linux-2.6-microblaze.git] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index f8614ef..ac32887 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2380,10 +2380,22 @@ retry:
                }
 
                /*
-                * Since we just failed the trylock; there must be an owner.
+                * The trylock just failed, so either there is an owner or
+                * there is a higher priority waiter than this one.
                 */
                newowner = rt_mutex_owner(&pi_state->pi_mutex);
-               BUG_ON(!newowner);
+               /*
+                * If the higher priority waiter has not yet taken over the
+                * rtmutex then newowner is NULL. We can't return here with
+                * that state because it's inconsistent vs. the user space
+                * state. So drop the locks and try again. It's a valid
+                * situation and not any different from the other retry
+                * conditions.
+                */
+               if (unlikely(!newowner)) {
+                       err = -EAGAIN;
+                       goto handle_err;
+               }
        } else {
                WARN_ON_ONCE(argowner != current);
                if (oldowner == current) {