Messages in this thread | | | Date | Tue, 27 Dec 2011 14:07:38 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH block/for-3.3/core] block: an exiting task should be allowed to create io_context |
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On Sun, 25 Dec 2011 14:29:34 +0100 Jens Axboe <axboe@kernel.dk> wrote:
> On 2011-12-25 02:02, Tejun Heo wrote: > > While fixing io_context creation / task exit race condition, > > 6e736be7f2 "block: make ioc get/put interface more conventional and > > fix race on alloction" also prevented an exiting (%PF_EXITING) task > > from creating its own io_context. This is incorrect as exit path may > > issue IOs, e.g. from exit_files(), and if those IOs are the first ones > > issued by the task, io_context needs to be created to process the IOs. > > > > Combined with the existing problem of io_context / io_cq creation > > failure having the possibility of stalling IO, this problem results in > > deterministic full IO lockup with certain workloads. > > > > Fix it by allowing io_context creation regardless of %PF_EXITING for > > %current.
The patch works for me.
> Thanks, applied.
So we get another great big bisection hole in mainline. I feel duty bound to rewhine about this :(
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