On Thu, Sep 22, 2022 at 11:45:15PM +0900, Suwan Kim wrote:
> Hi Michael,
>
> Can this patch be merged to the next rc?
> We received two bug reports about this issue and need to fix it.
>
> Regards,
> Suwan Kim
>
>
> On Wed, Aug 31, 2022 at 9:44 PM Pankaj Raghav <pankydev8@xxxxxxxxx> wrote:
> >
> > On Wed, Aug 31, 2022 at 12:01:53AM +0900, Suwan Kim wrote:
> > > If a request fails at virtio_queue_rqs(), it is inserted to requeue_list
> > > and passed to virtio_queue_rq(). Then blk_mq_start_request() can be called
> > > again at virtio_queue_rq() and trigger WARN_ON_ONCE like below trace because
> > > request state was already set to MQ_RQ_IN_FLIGHT in virtio_queue_rqs()
> > > despite the failure.
> > >
> > > To avoid calling blk_mq_start_request() twice, This patch moves the
> > > execution of blk_mq_start_request() to the end of virtblk_prep_rq().
> > > And instead of requeuing failed request to plug list in the error path of
> > > virtblk_add_req_batch(), it uses blk_mq_requeue_request() to change failed
> > > request state to MQ_RQ_IDLE. Then virtblk can safely handle the request
> > > on the next trial.
> > >
> > > Fixes: 0e9911fa768f ("virtio-blk: support mq_ops->queue_rqs()")
> > > Reported-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> > > Tested-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> > > Signed-off-by: Suwan Kim <suwan.kim027@xxxxxxxxx>
> > > ---
> > Looks good.
> > Reviewed-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Stefan, Paolo, any feedback here?
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MST
