Commit 77f300b1 authored Apr 16, 2014 by Daeseok Youn Committed by Tejun Heo Apr 16, 2014

workqueue: fix bugs in wq_update_unbound_numa() failure path



wq_update_unbound_numa() failure path has the following two bugs.

- alloc_unbound_pwq() is called without holding wq->mutex; however, if
  the allocation fails, it jumps to out_unlock which tries to unlock
  wq->mutex.

- The function should switch to dfl_pwq on failure but didn't do so
  after alloc_unbound_pwq() failure.

Fix it by regrabbing wq->mutex and jumping to use_dfl_pwq on
alloc_unbound_pwq() failure.

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4c16bd32 ("workqueue: implement NUMA affinity for unbound workqueues")

parent c9eaa447

kernel/workqueue.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -4100,7 +4100,8 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
		if (!pwq) {
		pr_warning("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
		wq->name);
		goto out_unlock;
		mutex_lock(&wq->mutex);
		goto use_dfl_pwq;
		}

		/*