From: Bart Van Assche bvanassche@acm.org
commit 6e66b49392419f3fe134e1be583323ef75da1e4b upstream.
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
Fixes: ed76e329d74a ("blk-mq: abstract out queue map") # v5.0 Reported-by: syzbot+d44e1b26ce5c3e77458d@syzkaller.appspotmail.com Signed-off-by: Bart Van Assche bvanassche@acm.org Reviewed-by: Ming Lei ming.lei@redhat.com Reviewed-by: Chaitanya Kulkarni chaitanya.kulkarni@wdc.com Cc: Johannes Thumshirn jth@kernel.org Cc: Hannes Reinecke hare@suse.com Cc: Ming Lei ming.lei@redhat.com Cc: Christoph Hellwig hch@infradead.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- block/blk-mq.c | 8 ++++++++ 1 file changed, 8 insertions(+)
--- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2965,6 +2965,14 @@ static int blk_mq_alloc_rq_maps(struct b
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;