On 09/13/2016, 05:35 PM, Tejun Heo wrote: > Hello, > > On Sat, Sep 10, 2016 at 11:33:48AM +0200, Dmitry Vyukov wrote: >> Hit the WARNING with the patch. It showed "Showing busy workqueues and >> worker pools:" after the WARNING, but then no queue info. Was it >> already destroyed and removed from the list?... > > Hmm... It either means that the work item which was in flight when > WARN_ON() ran finished by the time the debug printout got to it or > that it's something unrelated to busy work items. > >> [ 198.113838] WARNING: CPU: 2 PID: 26691 at kernel/workqueue.c:4042 >> destroy_workqueue+0x17b/0x630 > > I don't seem to have the same source code that you have. Which exact > WARN_ON() is this?
I assume Dmitry sees the same what I am still seeing, so I reported this some time ago: https://lkml.org/lkml/2016/3/21/492 This warning is trigerred there and still occurs with "HEAD": (pwq != wq->dfl_pwq) && (pwq->refcnt > 1) and the state dump is in the log empty too: destroy_workqueue: name='hci0' pwq=ffff88006b5c8f00 wq->dfl_pwq=ffff88006b5c9b00 pwq->refcnt=2 pwq->nr_active=0 delayed_works: pwq 13: cpus=2-3 node=1 flags=0x4 nice=-20 active=0/1 in-flight: 2669:wq_barrier_func thanks, -- js suse labs
