The patch below does not apply to the 6.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.4.y git checkout FETCH_HEAD git cherry-pick -x a7a7dabb5dd72d2875bc3ce56f94ea5ceb259d5b # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023081213-glamorous-appliance-33dd@gregkh' --subject-prefix 'PATCH 6.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From a7a7dabb5dd72d2875bc3ce56f94ea5ceb259d5b Mon Sep 17 00:00:00 2001 From: Ming Lei <ming.lei@xxxxxxxxxx> Date: Wed, 9 Aug 2023 10:04:40 +0800 Subject: [PATCH] nvme: core: don't hold rcu read lock in nvme_ns_chr_uring_cmd_iopoll Now nvme_ns_chr_uring_cmd_iopoll() has switched to request based io polling, and the associated NS is guaranteed to be live in case of io polling, so request is guaranteed to be valid because blk-mq uses pre-allocated request pool. Remove the rcu read lock in nvme_ns_chr_uring_cmd_iopoll(), which isn't needed any more after switching to request based io polling. Fix "BUG: sleeping function called from invalid context" because set_page_dirty_lock() from blk_rq_unmap_user() may sleep. Fixes: 585079b6e425 ("nvme: wire up async polling for io passthrough commands") Reported-by: Guangwu Zhang <guazhang@xxxxxxxxxx> Cc: Kanchan Joshi <joshi.k@xxxxxxxxxxx> Cc: Anuj Gupta <anuj20.g@xxxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> Tested-by: Guangwu Zhang <guazhang@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230809020440.174682-1-ming.lei@xxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c index 5c3250f36ce7..d39f3219358b 100644 --- a/drivers/nvme/host/ioctl.c +++ b/drivers/nvme/host/ioctl.c @@ -786,11 +786,9 @@ int nvme_ns_chr_uring_cmd_iopoll(struct io_uring_cmd *ioucmd, if (!(ioucmd->flags & IORING_URING_CMD_POLLED)) return 0; - rcu_read_lock(); req = READ_ONCE(ioucmd->cookie); if (req && blk_rq_is_poll(req)) ret = blk_rq_poll(req, iob, poll_flags); - rcu_read_unlock(); return ret; } #ifdef CONFIG_NVME_MULTIPATH
