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

Oleksandr Natalenko
2017-08-27T07:43:57Z

Hi.

Here is disk setup for QEMU VM:

===
[root@archmq ~]# smartctl -i /dev/sda
…
Device Model: QEMU HARDDISK
Serial Number: QM00001
Firmware Version: 2.5+
User Capacity: 4,294,967,296 bytes [4.29 GB]
Sector Size: 512 bytes logical/physical
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: ATA/ATAPI-7, ATA/ATAPI-5 published, ANSI NCITS 340-2000
Local Time is: Sun Aug 27 09:31:54 2017 CEST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

[root@archmq ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 4G 0 disk
`-sda1 8:1 0 4G 0 part
`-md0 9:0 0 4G 0 raid10
`-system 253:0 0 4G 0 crypt
|-system-boot 253:1 0 512M 0 lvm /boot
|-system-swap 253:2 0 512M 0 lvm [SWAP]
`-system-root 253:3 0 3G 0 lvm /
sdb 8:16 0 4G 0 disk
`-sdb1 8:17 0 4G 0 part
`-md0 9:0 0 4G 0 raid10
`-system 253:0 0 4G 0 crypt
|-system-boot 253:1 0 512M 0 lvm /boot
|-system-swap 253:2 0 512M 0 lvm [SWAP]
`-system-root 253:3 0 3G 0 lvm /
sr0 11:0 1 1024M 0 rom

[root@archmq ~]# mdadm --misc --detail /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Sat Jul 29 16:37:05 2017
Raid Level : raid10
Array Size : 4191232 (4.00 GiB 4.29 GB)
Used Dev Size : 4191232 (4.00 GiB 4.29 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent

Update Time : Sun Aug 27 09:30:33 2017
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0

Layout : far=2
Chunk Size : 512K

Name : archiso:0
UUID : 43f4be59:c8d2fa0a:a94acdff:1c7f2f4e
Events : 485

Number Major Minor RaidDevice State
0 8 1 0 active sync /dev/sda1
1 8 17 1 active sync /dev/sdb1
===

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.

On neděle 27. srpna 2017 8:02:00 CEST Ming Lei wrote:
> On Sat, Aug 26, 2017 at 12:48:01PM +0200, Oleksandr Natalenko wrote:
> > Quick update: reproduced on both v4.12.7 and v4.13.0-rc6.
>
> BTW, given it hangs during resume, it isn't easy to collect debug
> info, and there should have been lots useful info there.
>
> You mentioned that you can reproduce it on QEMU, could you
> share the exact raid10 setting? such as which disks behind
> the raid10.
>
> Or can you reproduce the issue without raid10 involved?
>
> I will try to reproduce it in my VM if you may provide the
> above info.
>
> Thanks,
> Ming