On 05/08, Jarek Poplawski wrote: > > On 08-05-2007 12:55, Oleg Nesterov wrote: > > On 05/08, Andrew Morton wrote: > >> On Tue, 08 May 2007 10:57:35 +0200 Jiri Slaby <jirislaby@xxxxxxxxx> wrote: > >> > >>> this occured in dmesg during resuming from hwsusp in 2.6.21-mm1 (captured > >>> through netconsole). Perfectly reproducible, it simply happens each time I > >>> try it. > >> Let's cc Oleg. > >> > >>> usb_endpoint usbdev5.1_ep00: PM: resume from 0, parent usb5 still 2 > >>> ------------[ cut here ]------------ > >>> kernel BUG at /home/l/latest/xxx/kernel/workqueue.c:106! > >>> invalid opcode: 0000 [#1] > >>> SMP > >>> Modules linked in: ipv6 floppy ohci1394 ieee1394 parport_pc parport usbhid > >>> ehci_hcd pata_acpi ff_memless sr_mod cdrom > ... > > queue_delayed_work(). > > > > Probably, cancel_delayed_work(&delayed_work->work) was called with the ->timer > > pending. This is wrong, cancel_delayed_work() clears _PENDING unconditionally, > > Maybe I miss your point, but clearing is conditional: on timer delete... > > I think more suspicious is calling cancel_work_sync() for a delayed work > (with timer pending). Or maybe some race profits from _PENDING cleared > without locking? Yes, of course, I meant cancel_work_sync(), sorry for the confusion. Thanks! So, once again, cancel_work_sync(&dwork->work) is wrong unless the timer was stopped. Before make-cancel_rearming_delayed_work-reliable.patch it requires that the @work can't be re-queued. After works, but waits for the timer expiration in a busy-wait loop. Oleg. _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
