Re: I/O hangs after resuming from suspend-to-ram

[Ming Lei <ming.lei@redhat.com>]

On Wed, Sep 20, 2017 at 07:25:02PM +0200, Martin Steigerwald wrote:
> Ming Lei - 28.08.17, 21:32:
> > On Mon, Aug 28, 2017 at 03:10:35PM +0200, Martin Steigerwald wrote:
> > > Ming Lei - 28.08.17, 20:58:
> > > > On Sun, Aug 27, 2017 at 09:43:52AM +0200, Oleksandr Natalenko wrote:
> > > > > Hi.
> > > > > 
> > > > > Here is disk setup for QEMU VM:
> […]
> > > > > In words: 2 virtual disks, RAID10 setup with far-2 layout, LUKS on it,
> > > > > then
> > > > > LVM, then ext4 for boot, swap and btrfs for /.
> > > > > 
> > > > > I couldn't reproduce the issue with single disk without RAID.
> > > > 
> > > > Could you verify if the following patch fixes your issue?
> > > 
> > > Could this also apply to non MD RAID systems? I am using BTRFS RAID
> > > 1 with two SSDs. So far with CFQ it runs stable.
> > 
> > It is for fixing Oleksandr's issue wrt. blk-mq, and looks not for you.
> 
> My findings are different:
> 
> On 4.12.10 with CONFIG_HZ=1000, CONFIG_PREEMPT=y and optimizations for Intel 
> Core/newer Xeon I see this:
> 
> 1) Running with CFQ: No hang after resume
> 
> 2) Running with scsi_mod.use_blk_mq=1 + BFQ: Hang after resume within first 1-2 
> days.

Hi Martin,

Thanks for your report!

Could you test the following patchset to see if it fixes your issue?

	https://marc.info/?l=linux-block&m=150579298505484&w=2


-- 
Ming