This is a note to let you know that I've just added the patch titled

nvme: fix hang in remove path

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: nvme-fix-hang-in-remove-path.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Mon Apr 9 17:09:24 CEST 2018

From: Ming Lei ming.lei@redhat.com Date: Fri, 2 Jun 2017 16:32:08 +0800 Subject: nvme: fix hang in remove path

From: Ming Lei ming.lei@redhat.com

[ Upstream commit 82654b6b8ef8b93ee87a97fc562f87f081fc2f91 ]

We need to start admin queues too in nvme_kill_queues() for avoiding hang in remove path[1].

This patch is very similar with 806f026f9b901eaf(nvme: use blk_mq_start_hw_queues() in nvme_kill_queues()).

[1] hang stack trace [<ffffffff813c9716>] blk_execute_rq+0x56/0x80 [<ffffffff815cb6e9>] __nvme_submit_sync_cmd+0x89/0xf0 [<ffffffff815ce7be>] nvme_set_features+0x5e/0x90 [<ffffffff815ce9f6>] nvme_configure_apst+0x166/0x200 [<ffffffff815cef45>] nvme_set_latency_tolerance+0x35/0x50 [<ffffffff8157bd11>] apply_constraint+0xb1/0xc0 [<ffffffff8157cbb4>] dev_pm_qos_constraints_destroy+0xf4/0x1f0 [<ffffffff8157b44a>] dpm_sysfs_remove+0x2a/0x60 [<ffffffff8156d951>] device_del+0x101/0x320 [<ffffffff8156db8a>] device_unregister+0x1a/0x60 [<ffffffff8156dc4c>] device_destroy+0x3c/0x50 [<ffffffff815cd295>] nvme_uninit_ctrl+0x45/0xa0 [<ffffffff815d4858>] nvme_remove+0x78/0x110 [<ffffffff81452b69>] pci_device_remove+0x39/0xb0 [<ffffffff81572935>] device_release_driver_internal+0x155/0x210 [<ffffffff81572a02>] device_release_driver+0x12/0x20 [<ffffffff815d36fb>] nvme_remove_dead_ctrl_work+0x6b/0x70 [<ffffffff810bf3bc>] process_one_work+0x18c/0x3a0 [<ffffffff810bf61e>] worker_thread+0x4e/0x3b0 [<ffffffff810c5ac9>] kthread+0x109/0x140 [<ffffffff8185800c>] ret_from_fork+0x2c/0x40 [<ffffffffffffffff>] 0xffffffffffffffff

Fixes: c5552fde102fc("nvme: Enable autonomous power state transitions") Reported-by: Rakesh Pandit rakesh@tuxera.com Tested-by: Rakesh Pandit rakesh@tuxera.com Reviewed-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/nvme/host/core.c | 4 ++++ 1 file changed, 4 insertions(+)

--- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2040,6 +2040,10 @@ void nvme_kill_queues(struct nvme_ctrl * struct nvme_ns *ns;

mutex_lock(&ctrl->namespaces_mutex); + + /* Forcibly start all queues to avoid having stuck requests */ + blk_mq_start_hw_queues(ctrl->admin_q); + list_for_each_entry(ns, &ctrl->namespaces, list) { /* * Revalidating a dead namespace sets capacity to 0. This will

Patches currently in stable-queue which might be from ming.lei@redhat.com are

queue-4.9/blk-mq-fix-kernel-oops-in-blk_mq_tag_idle.patch queue-4.9/nvme-fix-hang-in-remove-path.patch queue-4.9/fix-loop-device-flush-before-configure-v3.patch queue-4.9/blk-mq-fix-race-between-updating-nr_hw_queues-and-switching-io-sched.patch