On Thu, 2018-02-22 at 14:42 -0800, Omar Sandoval wrote: > On Thu, Feb 22, 2018 at 09:10:23PM +0000, Bart Van Assche wrote: > > I/O hangs if I run the following command on top of kernel v4.16-rc2 + the > > ib_srpt patch that adds RDMA/CM support: > > > > srp-test/run_tests -c -d -r 10 -t 02-mq -e kyber > > > > This does not happen with the deadline scheduler nor without a scheduler. > > This test passed a few months ago. I have attached the output of the following > > command to this e-mail: > > > > (cd /sys/kernel/debug/block && grep -r .) | grep -v /poll_stat > > > > Can you have a look? > > Hey, Bart, thanks for the report. Can you clarify what the device > topology is w.r.t. the dm devices? Hello Omar, The topology was nothing fancy: dm-rq in blk-mq mode was configured to use one scsi-mq SRP-over-RoCE path. The multipath output is as follows: # multipath -ll mpathb (3600140572616d6469736b31000000000) dm-0 LIO-ORG,IBLOCK size=32M features='3 queue_if_no_path queue_mode mq' hwhandler='0' wp=rw `-+- policy='service-time 0' prio=50 status=active `- 4:0:0:0 sdc 8:32 active ready running # for d in /sys/block/{dm-0,sdc}; do echo $(basename $d): $(<$d/queue/scheduler); done dm-0: bfq [kyber] mq-deadline none sdc: bfq [kyber] mq-deadline none Bart.