On Thu, Dec 10, 2015 at 11:28:02AM +0200, Nikolay Borisov wrote: > On 12/09/2015 06:27 PM, Tejun Heo wrote: > > Hello, > > > > On Wed, Dec 09, 2015 at 06:23:15PM +0200, Nikolay Borisov wrote: > >> I think we are seeing this at least daily on at least 1 server (we have > >> multiple servers like that). So adding printk's would likely be the way > >> to go, anything in particular you might be interested in knowing? I see > >> RCU stuff around so might be tricky race condition. > > > > Printing out the workqueue's pointer, name, pwq's pointer, the node > > being installed for and the installed pointer should give us enough > > clues. There's RCU involved but the pointers shouldn't be becoming > > NULLs unless we're installing NULL ptrs. > > So the debug patch has been rolled on 1 server and several more > are in the process, here it is what it prints: > > WQ: ffff88046f00ba00 (events_unbound) old_pwq: (null) new_pwq: > ffff88046f00d300 node: 0 ... > Is this format ok? Also I observed the exact same crash > on a machine running 4.1.12 kernel as well.
Yeah, I think it can be a good starting point. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
