From: Ming Lei Date: Mon, 14 Oct 2024 00:51:15 +0000 (+0800) Subject: blk-mq: setup queue ->tag_set before initializing hctx X-Git-Tag: nvme-6.12-2024-10-31~9 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=c25c0c9035bb8b28c844dfddeda7b8bdbcfcae95;p=nvme.git blk-mq: setup queue ->tag_set before initializing hctx Commit 7b815817aa58 ("blk-mq: add helper for checking if one CPU is mapped to specified hctx") needs to check queue mapping via tag set in hctx's cpuhp handler. However, q->tag_set may not be setup yet when the cpuhp handler is enabled, then kernel oops is triggered. Fix the issue by setup queue tag_set before initializing hctx. Cc: stable@vger.kernel.org Reported-and-tested-by: Rick Koch Closes: https://lore.kernel.org/linux-block/CANa58eeNDozLaBHKPLxSAhEy__FPfJT_F71W=sEQw49UCrC9PQ@mail.gmail.com Fixes: 7b815817aa58 ("blk-mq: add helper for checking if one CPU is mapped to specified hctx") Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Reviewed-by: John Garry Link: https://lore.kernel.org/r/20241014005115.2699642-1-ming.lei@redhat.com Signed-off-by: Jens Axboe --- diff --git a/block/blk-mq.c b/block/blk-mq.c index 4b2c8e940f59..cf626e061dd7 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4310,6 +4310,12 @@ int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, /* mark the queue as mq asap */ q->mq_ops = set->ops; + /* + * ->tag_set has to be setup before initialize hctx, which cpuphp + * handler needs it for checking queue mapping + */ + q->tag_set = set; + if (blk_mq_alloc_ctxs(q)) goto err_exit; @@ -4328,8 +4334,6 @@ int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, INIT_WORK(&q->timeout_work, blk_mq_timeout_work); blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ); - q->tag_set = set; - q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT; INIT_DELAYED_WORK(&q->requeue_work, blk_mq_requeue_work);