On 02/27/2017 08:15 PM, Keith Busch wrote: > On Mon, Feb 27, 2017 at 07:27:51PM +0200, Sagi Grimberg wrote: >> OK, I think we can get it for fabrics too, need to figure out how to >> handle it there too. >> >> Do you have a reproducer? > > To repro, I have to run a buffered writer workload then put the system into S3. > > This fio job seems to reproduce for me: > > fio --name=global --filename=/dev/nvme0n1 --bsrange=4k-128k --rw=randwrite --ioengine=libaio --iodepth=8 --numjobs=8 --name=foobar > > I use rtcwake to test suspend/resume: > > rtcwake -m mem -s 10 > > Without the patch we'll get stuck after "Disabling non-boot CPUs ..." > when blk-mq waits to freeze some entered queues after nvme was disabled. I'm observing the same thing when hibernating during mdraid resync on nvme - it hangs in blk_mq_freeze_queue_wait() after "Disabling non-boot CPUs ...". This patch did not help but when I put nvme_wait_freeze() right after nvme_start_freeze() it appeared to be working. Maybe the difference here is that requests are submitted from a non-freezable kernel thread (md sync_thread)? Thanks, Artur
