From: Zhihao Cheng chengzhihao1@huawei.com
[ Upstream commit 7764656b108cd308c39e9a8554353b8f9ca232a3 ]
Followling process: nvme_probe nvme_reset_ctrl nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING) queue_work(nvme_reset_wq, &ctrl->reset_work)
--------------> nvme_remove nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING) worker_thread process_one_work nvme_reset_work WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING)
, which will trigger WARN_ON in nvme_reset_work(): [ 127.534298] WARNING: CPU: 0 PID: 139 at drivers/nvme/host/pci.c:2594 [ 127.536161] CPU: 0 PID: 139 Comm: kworker/u8:7 Not tainted 5.13.0 [ 127.552518] Call Trace: [ 127.552840] ? kvm_sched_clock_read+0x25/0x40 [ 127.553936] ? native_send_call_func_single_ipi+0x1c/0x30 [ 127.555117] ? send_call_function_single_ipi+0x9b/0x130 [ 127.556263] ? __smp_call_single_queue+0x48/0x60 [ 127.557278] ? ttwu_queue_wakelist+0xfa/0x1c0 [ 127.558231] ? try_to_wake_up+0x265/0x9d0 [ 127.559120] ? ext4_end_io_rsv_work+0x160/0x290 [ 127.560118] process_one_work+0x28c/0x640 [ 127.561002] worker_thread+0x39a/0x700 [ 127.561833] ? rescuer_thread+0x580/0x580 [ 127.562714] kthread+0x18c/0x1e0 [ 127.563444] ? set_kthread_struct+0x70/0x70 [ 127.564347] ret_from_fork+0x1f/0x30
The preceding problem can be easily reproduced by executing following script (based on blktests suite): test() { pdev="$(_get_pci_dev_from_blkdev)" sysfs="/sys/bus/pci/devices/${pdev}" for ((i = 0; i < 10; i++)); do echo 1 > "$sysfs/remove" echo 1 > /sys/bus/pci/rescan done }
Since the device ctrl could be updated as an non-RESETTING state by repeating probe/remove in userspace (which is a normal situation), we can replace stack dumping WARN_ON with a warnning message.
Fixes: 82b057caefaff ("nvme-pci: fix multiple ctrl removal schedulin") Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 80e1d45b0668..fb48a88d1acb 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2596,7 +2596,9 @@ static void nvme_reset_work(struct work_struct *work) bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL); int result;
- if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING)) { + if (dev->ctrl.state != NVME_CTRL_RESETTING) { + dev_warn(dev->ctrl.device, "ctrl state %d is not RESETTING\n", + dev->ctrl.state); result = -ENODEV; goto out; }