[libvirt] [frankschreuder at outlook.com: Fwd: Reproducible live disk detach bug]

[Richard W.M. Jones]

Forwarding from Frank Schreuder who was having some issues
sending this to the mailing list.

----- Begin forwarded message -----

> Subject: Reproducible live disk detach bug
> 
> Hey guys,
> 
> I am currently running into a reproducible libvirt bug when I detach a
> disk from a running VM using libvirt 1.2.18 and qemu 2.3.0.
> 
> I can attach a disk to a running VM without any problems.
> During the attach operation I don't create a disk alias name, which
> results in libvirt generating an unique alias.
> Using virsh dumpxml I get the following output(snippet):
> 
> <disk type='file' device='disk'>
>       <driver name='qemu' type='raw' cache='none'/>
>       <source file='/var/local/mnt/test-storage/test-storage.raw'/>
>       <backingStore/>
>       <target dev='vde' bus='virtio'/>
>       <iotune>
>         <read_bytes_sec>94371840</read_bytes_sec>
>         <write_bytes_sec>31457280</write_bytes_sec>
>         <read_iops_sec>1000</read_iops_sec>
>         <write_iops_sec>200</write_iops_sec>
>       </iotune>
>       <alias name='virtio-disk4'/>
>       <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
> </disk>
> 
> As you can see, libvirt generates 'virtio-disk4' as an alias. But as
> soon as I try to detach the disk from the running VM, I will receive the
> following two errors in my libvirt log:
> 
> 2015-08-06 10:48:59.943+0000: 11657: warning :
> qemuMonitorJSONHandleDeviceDeleted:939 : missing device in device
> deleted event
> 2015-08-06 10:48:59.945+0000: 11662: error :
> qemuMonitorTextDriveDel:2594 : operation failed: deleting
> drive-virtio-disk4 drive failed: 2015-08-06T10:48:59.945058Z Device
> 'drive-virtio-disk4' not found
> 
> Apparently libvirt tries to detach the disk with a drive- prefix, which
> doesn't exist? The drive seems to detach correctly though.
> 
> I hope somebody with more extensive knowledge about libvirt can help me
> solve this issue. If more information is needed, feel free to contact me.
> 
> Thanks,
> Frank

----- End forwarded message -----

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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