Bug 811110

Summary:	Qemu complains no space left during installation and migration while actually it should be enough
Product:	Red Hat Enterprise Linux 6	Reporter:	Qunfang Zhang <qzhang>
Component:	qemu-kvm	Assignee:	Kevin Wolf <kwolf>
Status:	CLOSED NOTABUG	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.3	CC:	acathrow, areis, bsarathy, dyasny, juzhang, kwolf, michen, mkenneth, virt-maint
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-04-11 05:28:39 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Qunfang Zhang 2012-04-10 07:31:24 UTC

Description of problem:
This issue is found during test bug 760899 on a rhel6.3 host. Install and migrate a guest (I used win7-64) between 2 hosts and the images is
located on a iscsi storage. Create a small LV and enlarge it with "lvextend"
command when there's no space to proceed installation. I enlarge it to 20G which is large enough to install the guest. But after migration guest still stops and prompts there's no enough space to continue installation.

Version-Release number of selected component (if applicable):
kernel-2.6.32-261.el6.x86_64
qemu-kvm-0.12.1.2-2.270.el6.x86_64
seabios-0.6.1.2-16.el6.x86_64

How reproducible:
Always

Steps to Reproduce:
0. Create the lv and image file and *make sure the image is valid and active on
both 2 hosts*.
#vgcreate vgtest-qzhang /dev/sdb1
#lvcreate -n lv-install -L 1G vgtest-qzhang
#qemu-img create -f qcow2 /dev/vgtest-qzhang/lv-installation 20G

1.Boot a win7 guest on host A and start installation (from iscsi disk):

/usr/libexec/qemu-kvm -M rhel6.3.0 -cpu Conroe -no-kvm-pit-reinjection -rtc-td-hack -enable-kvm -m 2G -smp 2,sockets=1,cores=2,threads=1 -name rhel5.8 -uuid c1392688-189d-4b8b-a170-a8939dad2d18 -rtc base=localtime,driftfix=slew -drive file=/dev/vgtest-qzhang/lv-installation,if=none,id=drive-virtio-disk0,format=qcow2,cache=none,werror=stop,rerror=stop,aio=native -device virtio-blk-pci,bus=pci.0,drive=drive-virtio-disk0,id=virtio-disk0 -netdev tap,id=hostnet0,vhost=on,script=/etc/qemu-ifup -device virtio-net-pci,netdev=hostnet0,id=net0,mac=00:1a:2a:28:18:22,bus=pci.0 -usb -device usb-tablet,id=input0 -boot dc -monitor stdio  -drive file=/mnt/en_windows_7_ultimate_with_sp1_x64_dvd_618240.iso,if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw -device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -fda /mnt/virtio-win-1.4.0.vfd -spice port=5930,disable-ticketing -vga qxl -global qxl-vga.vram_size=67108864

2. Boot guest with "-incoming tcp:0:5800" on host B.

3. Migration guest from host A to host B.

4. On host B, wait for guest finishes installation and stops due to no enough space.

5. On host B, when guest stops, enlarge the LV to 20G
# lvextend -L +19G /dev/vgtest-qzhang/lv-installation 
  Extending logical volume lv-installation to 20.00 GiB

6. Check on host A, to see if the LV is enlarged
#lvs

7. On host B. continue guest with 'cont' command and migration it back to host A
(qemu)cont
(qemu)migrate -d tcp:$host_A_IP:5800

  
Actual results:
Guest is migrated to host A, but still stops and prompts no enough space. Actually if I install the guest with 20G disk directly, it's large enough.

Expected results:
Guest should migrate and install successfully.

Additional info:

Comment 1 Qunfang Zhang 2012-04-10 07:35:44 UTC

After step 7:

spice_server_add_interface: SPICE_INTERFACE_TABLET
block I/O error in device 'drive-virtio-disk0': No space left on device (28)
handle_dev_stop: stop
block I/O error in device 'drive-virtio-disk0': No space left on device (28)
block I/O error in device 'drive-virtio-disk0': No space left on device (28)
block I/O error in device 'drive-virtio-disk0': No space left on device (28)
block I/O error in device 'drive-virtio-disk0': No space left on device (28)
block I/O error in device 'drive-virtio-disk0': No space left on device (28)

(qemu) 
(qemu) info status 
VM status: paused (io-error)


[root@t1 ~]# lvs
  LV              VG            Attr     LSize   Pool Origin Data%  Move Log Copy%  Convert                                           
  lv-installation vgtest-qzhang -wi-ao--  20.00g                                           
[root@t1 ~]# 
[root@t1 ~]# 
[root@t1 ~]# 
[root@t1 ~]# qemu-img info /dev/vgtest-qzhang/lv-installation 
image: /dev/vgtest-qzhang/lv-installation
file format: qcow2
virtual size: 20G (21474836480 bytes)
disk size: 0
cluster_size: 65536

Comment 3 Kevin Wolf 2012-04-10 08:35:39 UTC

When do you start qemu -incoming on host A? Is it before or after the lvextend?

Comment 4 Qunfang Zhang 2012-04-11 05:28:39 UTC

(In reply to comment #3)
> When do you start qemu -incoming on host A? Is it before or after the lvextend?

Hi, Kevin
Re-test again, it will happen on both start qemu -incoming before and after the
lvextend.

And please check bug 683721 - qemu still claims ENOSPAC even if enlarge the
image when doing migration. (closed as not a bug)

When I tried the method in the bug 683721 comment 11, this bug will not exist
any more.

"(If you run fdisk -l <lv path> on dest the sizeis still 512M).
If you run "lvmchange --refresh <LV path> " , and continue the dest vm
everything run smoothly."

So, I would like to close this bug. Please correct me if I am wrong.

Comment 5 Kevin Wolf 2012-04-11 10:18:59 UTC

Thanks for investigating. Closing the bug looks right to me.