Bug 1302168

Created attachment 1118646 [details]
libvirtd.log

commit b4698538123d57808e1b904b3d06d1adaf7f3624
Author: Peter Krempa <pkrempa>
Date:   Fri Dec 16 16:06:57 2016 +0100

    qemu: blockjob: Fix locking of block copy/active block commit
    
    For the blockjobs, where libvirt is able to track the state internally
    we can fix locking of images we can remove the appropriate locks.
    
    Also when doing a pivoting operation we should not acquire the lock on
    any of those images since both are actually locked already.

Verified on:
======
libvirt-3.0.0-2.el7.x86_64
qemu-kvm-rhev-2.8.0-4.el7.x86_64


PASSED


Steps:
======
1. Preparing virlockd environment
# cat /etc/libvirt/qemu-lockd.conf
auto_disk_leases = 1
require_lease_for_disks = 1
file_lockspace_dir = "/var/lib/libvirt/lockd/scsivolumes"

# cat /etc/libvirt/qemu.conf
lock_manager = "lockd"

# systemctl restart virtlockd && systemctl restart libvirtd

2. prepare a transient vm
## virsh start vm1
lDomain vm1 started

## virsh list
 Id    Name                           State
----------------------------------------------------
 11    vm1                            running


## virsh undefine vm1
Domain vm1 has been undefined

3. check the lock file
## ll /var/lib/libvirt/lockd/scsivolumes
total 0
-rw-------. 1 root root 0 Mar  2 16:45 4a871df074d9339f152adf33b7dd7b81c21d427e88009d3606aa78617a422c98

4. Do the blockcopy and check a new lock file generated for the copied file
 ## virsh blockcopy vm1 vda /var/lib/libvirt/images/vm1.cpy --wait --verbose
Block Copy: [100 %]
Now in mirroring phase

 ## virsh dumpxml vm1 | grep cpy -a10
  ...
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/RHEL-7.3-latest.img'/>
      <backingStore/>
      <mirror type='file' file='/var/lib/libvirt/images/vm1.cpy' format='qcow2' job='copy' ready='yes'>
        <format type='qcow2'/>
        <source file='/var/lib/libvirt/images/vm1.cpy'/>
      </mirror>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </disk>
...

## ll /var/lib/libvirt/lockd/scsivolumes
total 0
-rw-------. 1 root root 0 Mar  2 16:56 2bc4f0846679db12a738f2019cb3014439047f4357cccdf106e602f2855718f9
-rw-------. 1 root root 0 Mar  2 16:53 4a871df074d9339f152adf33b7dd7b81c21d427e88009d3606aa78617a422c98
5. do the blockjob pivot
## virsh blockjob vm1 vda --pivot
6. check one lock file for the original vda gone
## ll /var/lib/libvirt/lockd/scsivolumes
total 0
-rw-------. 1 root root 0 Mar  2 16:56 2bc4f0846679db12a738f2019cb3014439047f4357cccdf106e602f2855718f9
## virsh dumpxml vm1 | grep cpy -a10
  ...
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/vm1.cpy'/>
      <backingStore/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </disk>
...

7. login the vm and check the os works well
## virsh console vm1
Connected to domain vm1
Escape character is ^]

Red Hat Enterprise Linux Server 7.3 Beta (Maipo)
Kernel 3.10.0-461.el7.x86_64 on an x86_64

yisun_vm1 login: root
Password:
Last login: Wed Mar  1 18:16:39 on ttyS0
[root@yisun_vm1 ~]# uname -r
3.10.0-461.el7.x86_64

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2017:1846

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2017:1846