On Fri, Mar 6, 2020 at 10:47 AM Ming Lei <ming.lei@xxxxxxxxxx> wrote:
>
> On Tue, Feb 25, 2020 at 08:47:27AM +0800, Ming Lei wrote:
> > On Thu, Feb 20, 2020 at 07:22:37PM -0800, Bart Van Assche wrote:
> > > blk_mq_map_queues() and multiple .map_queues() implementations expect that
> > > set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the number of hardware
> > > queues. Hence set .nr_queues before calling these functions. This patch
> > > fixes the following kernel warning:
> > >
> > > WARNING: CPU: 0 PID: 2501 at include/linux/cpumask.h:137
> > > Call Trace:
> > > blk_mq_run_hw_queue+0x19d/0x350 block/blk-mq.c:1508
> > > blk_mq_run_hw_queues+0x112/0x1a0 block/blk-mq.c:1525
> > > blk_mq_requeue_work+0x502/0x780 block/blk-mq.c:775
> > > process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
> > > worker_thread+0x98/0xe40 kernel/workqueue.c:2415
> > > kthread+0x361/0x430 kernel/kthread.c:255
> > >
> > > Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> > > Cc: Ming Lei <ming.lei@xxxxxxxxxx>
> > > Cc: Hannes Reinecke <hare@xxxxxxxx>
> > > Cc: Johannes Thumshirn <jth@xxxxxxxxxx>
> > > Reported-by: syzbot+d44e1b26ce5c3e77458d@xxxxxxxxxxxxxxxxxxxxxxxxx
> > > Fixes: ed76e329d74a ("blk-mq: abstract out queue map") # v5.0
> > > Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
> > > ---
> > > block/blk-mq.c | 8 ++++++++
> > > 1 file changed, 8 insertions(+)
> > >
> > > diff --git a/block/blk-mq.c b/block/blk-mq.c
> > > index f298500e6dda..a92444c077bc 100644
> > > --- a/block/blk-mq.c
> > > +++ b/block/blk-mq.c
> > > @@ -3023,6 +3023,14 @@ static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set)
> > >
> > > static int blk_mq_update_queue_map(struct blk_mq_tag_set *set)
> > > {
> > > + /*
> > > + * blk_mq_map_queues() and multiple .map_queues() implementations
> > > + * expect that set->map[HCTX_TYPE_DEFAULT].nr_queues is set to the
> > > + * number of hardware queues.
> > > + */
> > > + if (set->nr_maps == 1)
> > > + set->map[HCTX_TYPE_DEFAULT].nr_queues = set->nr_hw_queues;
> > > +
> > > if (set->ops->map_queues && !is_kdump_kernel()) {
> > > int i;
> > >
> > >
> >
> > Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
> >
>
> Hi Jens,
>
> This one and the 3rd patch may belong to 5.6, any chance to consider
> them to 5.6?
Just got test feedback from one RH partner, the patch fixes kernel oops
on NVMe FC when updating nr_hw_queues.
Thanks,
Ming Lei
