Commits
Sagi Grimberg committed 0157ec8dad3
nvme: fix controller removal race with scan work
With multipath enabled, nvme_scan_work() can read from the device
(through nvme_mpath_add_disk()) and hang [1]. However, with fabrics,
once ctrl->state is set to NVME_CTRL_DELETING, the reads will hang
(see nvmf_check_ready()) and the mpath stack device make_request
will block if head->list is not empty. However, when the head->list
consistst of only DELETING/DEAD controllers, we should actually not
block, but rather fail immediately.
In addition, before we go ahead and remove the namespaces, make sure
to clear the current path and kick the requeue list so that the
request will fast fail upon requeuing.
[1]:
--
INFO: task kworker/u4:3:166 blocked for more than 120 seconds.
Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:3 D 0 166 2 0x80004000
Workqueue: nvme-wq nvme_scan_work
Call Trace:
__schedule+0x851/0x1400
schedule+0x99/0x210
io_schedule+0x21/0x70
do_read_cache_page+0xa57/0x1330
read_cache_page+0x4a/0x70
read_dev_sector+0xbf/0x380
amiga_partition+0xc4/0x1230
check_partition+0x30f/0x630
rescan_partitions+0x19a/0x980
__blkdev_get+0x85a/0x12f0
blkdev_get+0x2a5/0x790
__device_add_disk+0xe25/0x1250
device_add_disk+0x13/0x20
nvme_mpath_set_live+0x172/0x2b0
nvme_update_ns_ana_state+0x130/0x180
nvme_set_ns_ana_state+0x9a/0xb0
nvme_parse_ana_log+0x1c3/0x4a0
nvme_mpath_add_disk+0x157/0x290
nvme_validate_ns+0x1017/0x1bd0
nvme_scan_work+0x44d/0x6a0
process_one_work+0x7d7/0x1240
worker_thread+0x8e/0xff0
kthread+0x2c3/0x3b0
ret_from_fork+0x35/0x40
INFO: task kworker/u4:1:1034 blocked for more than 120 seconds.
Not tainted 5.2.0-rc6-vmlocalyes-00005-g808c8c2dc0cf #316
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:1 D 0 1034 2 0x80004000
Workqueue: nvme-delete-wq nvme_delete_ctrl_work
Call Trace:
__schedule+0x851/0x1400
schedule+0x99/0x210
schedule_timeout+0x390/0x830
wait_for_completion+0x1a7/0x310
__flush_work+0x241/0x5d0
flush_work+0x10/0x20
nvme_remove_namespaces+0x85/0x3d0
nvme_do_delete_ctrl+0xb4/0x1e0
nvme_delete_ctrl_work+0x15/0x20
process_one_work+0x7d7/0x1240
worker_thread+0x8e/0xff0
kthread+0x2c3/0x3b0
ret_from_fork+0x35/0x40
--
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Tested-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>