[PATCH RT 20/25][RFC 3.0.23-rt39-rc1] futex/rt: Fix possible lockup when taking pi_lock in proxy handler
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2012-03-06 16:58:34
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Steven Rostedt <rostedt@goodmis.org> When taking the pi_lock, we must disable interrupts because the pi_lock can also be taken in an interrupt handler. Use raw_spin_lock_irq() instead of raw_spin_lock(). Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Carsten Emde <redacted> Cc: John Kacur <jkacur@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Clark Williams <redacted> Cc: stable-rt@vger.kernel.org Link: http://lkml.kernel.org/r/20120301190345.165160680@goodmis.org Signed-off-by: Thomas Gleixner <redacted> --- kernel/rtmutex.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index 789744a..a02fbd9 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c@@ -1365,14 +1365,14 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock, * PI_REQUEUE_INPROGRESS, so that if the task is waking up * it will know that we are in the process of requeuing it. */ - raw_spin_lock(&task->pi_lock); + raw_spin_lock_irq(&task->pi_lock); if (task->pi_blocked_on) { - raw_spin_unlock(&task->pi_lock); + raw_spin_unlock_irq(&task->pi_lock); raw_spin_unlock(&lock->wait_lock); return -EAGAIN; } task->pi_blocked_on = PI_REQUEUE_INPROGRESS; - raw_spin_unlock(&task->pi_lock); + raw_spin_unlock_irq(&task->pi_lock); #endif ret = task_blocks_on_rt_mutex(lock, waiter, task, detect_deadlock);
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1.7.8.3