While using the block fake timeout injector to reproduce a nvme error handling hang, a hang was observed when the following script was run: echo 100 > /sys/kernel/debug/fail_io_timeout/probability echo 1000 > /sys/kernel/debug/fail_io_timeout/times echo 1 > /sys/block/nvme0n1/io-timeout-fail dd if=/dev/nvme0n1 of=/dev/null bs=512 count=1 dmesg: [ 370.018164] INFO: task kworker/u113:9:1191 blocked for more than 122 seconds. [ 370.018849] Not tainted 5.7.0-rc4 #1 [ 370.019251] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 370.019653] kworker/u113:9 D 0 1191 2 0x80004000 [ 370.019660] Workqueue: nvme-reset-wq nvme_reset_work [nvme] [ 370.019661] Call Trace: [ 370.019667] __schedule+0x2dc/0x710 [ 370.019668] schedule+0x44/0xb0 [ 370.019671] blk_mq_freeze_queue_wait+0x4b/0xb0 [ 370.019675] ? finish_wait+0x80/0x80 [ 370.019681] nvme_wait_freeze+0x36/0x50 [nvme_core] [ 370.019683] nvme_reset_work+0xb65/0xf2b [nvme] [ 370.019688] process_one_work+0x1ab/0x380 [ 370.019689] worker_thread+0x37/0x3b0 [ 370.019691] kthread+0x120/0x140 [ 370.019692] ? create_worker+0x1b0/0x1b0 [ 370.019693] ? kthread_park+0x90/0x90 [ 370.019696] ret_from_fork+0x35/0x40 This occurs when a fake timeout is scheduled on a request that is in he process of being cancelled due to the previous fake timeout. Alan Adamson (1): block: don't inject fake timeouts on quiesced queues block/blk-timeout.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) -- 1.8.3.1
