path: root/virt
diff options
authorLai Jiangshan <laijs@cn.fujitsu.com>2014-02-15 22:02:28 +0800
committerTejun Heo <tj@kernel.org>2014-02-18 16:35:20 -0500
commit5bdfff96c69a4d5ab9c49e60abf9e070ecd2acbb (patch)
treedab862c9f8694478b58adf92d3e1c87ba5a24a44 /virt
parentfada94ee64e6e18793b1db60fb8278d2eddbf922 (diff)
workqueue: ensure @task is valid across kthread_stop()
When a kworker should die, the kworkre is notified through WORKER_DIE flag instead of kthread_should_stop(). This, IIRC, is primarily to keep the test synchronized inside worker_pool lock. WORKER_DIE is first set while holding pool->lock, the lock is dropped and kthread_stop() is called. Unfortunately, this means that there's a slight chance that the target kworker may see WORKER_DIE before kthread_stop() finishes and exits and frees the target task before or during kthread_stop(). Fix it by pinning the target task before setting WORKER_DIE and putting it after kthread_stop() is done. tj: Improved patch description and comment. Moved pinning above WORKER_DIE for better signify what it's protecting. CC: stable@vger.kernel.org Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'virt')
0 files changed, 0 insertions, 0 deletions