Messages in this thread Patch in this message | | | Date | Fri, 13 May 2016 17:18:10 -0400 | From | Tejun Heo <> | Subject | [GIT PULL] workqueue fixes for v4.6-rc7 |
| |
Hello, Linus.
CPU hotplug callbacks can invoke DOWN_FAILED w/o preceding DOWN_PREPARE which can trigger a WARN_ON() in workqueue. The bug has been there for a very long time. It only triggers if CPU down fails at a specific point and I don't think it has adverse effects other than the warning messages. The fix is very low impact.
Thanks.
The following changes since commit 346c09f80459a3ad97df1816d6d606169a51001a:
workqueue: fix ghost PENDING flag while doing MQ IO (2016-04-26 11:23:22 -0400)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-4.6-fixes
for you to fetch changes up to f7c17d26f43d5cc1b7a6b896cd2fa24a079739b9:
workqueue: fix rebind bound workers warning (2016-05-12 12:00:23 -0400)
---------------------------------------------------------------- Wanpeng Li (1): workqueue: fix rebind bound workers warning
kernel/workqueue.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 801a698..1b2e36b 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -4555,6 +4555,17 @@ static void rebind_workers(struct worker_pool *pool) pool->attrs->cpumask) < 0); spin_lock_irq(&pool->lock); + + /* + * XXX: CPU hotplug notifiers are weird and can call DOWN_FAILED + * w/o preceding DOWN_PREPARE. Work around it. CPU hotplug is + * being reworked and this can go away in time. + */ + if (!(pool->flags & POOL_DISASSOCIATED)) { + spin_unlock_irq(&pool->lock); + return; + } + pool->flags &= ~POOL_DISASSOCIATED; for_each_pool_worker(worker, pool) {
| |