libvirt users - Apr 2019 - Failed to probe capabilities on libvirt v5.1.0

Hi everyone,

Unfortunately, I'm facing an issue with libvirt 5.1.0 when probing
capabilities.

Failed to probe capabilities for /usr/bin/qemu-system-x86_64: internal
error: Failed to start QEMU binary /usr/bin/qemu-system-x86_64 for
probing: qemu-system-x86_64: cannot create PID file: Cannot open pid
file: Permission denied

I see that the qmp directory is being created, however, it belongs to
root instead of qemu:

/var/lib/libvirt/qemu/qmp-U1w6o6:
0 drwx------. 2 root root   6 Apr 11 14:46 qmp-U1w6o6

The user and group are set to "qemu" in /etc/libvirt/qemu.conf

I would appreciate any pointers.
Thank you!

Vladik

On 4/11/19 6:20 PM, Vladik Romanovsky wrote:
> Hi everyone,
> 
> Unfortunately, I'm facing an issue with libvirt 5.1.0 when probing
capabilities.
> 
> Failed to probe capabilities for /usr/bin/qemu-system-x86_64: internal
> error: Failed to start QEMU binary /usr/bin/qemu-system-x86_64 for
> probing: qemu-system-x86_64: cannot create PID file: Cannot open pid
> file: Permission denied
> 
> I see that the qmp directory is being created, however, it belongs to
> root instead of qemu:
> 
> /var/lib/libvirt/qemu/qmp-U1w6o6:
> 0 drwx------. 2 root root   6 Apr 11 14:46 qmp-U1w6o6
> 
> The user and group are set to "qemu" in /etc/libvirt/qemu.conf
Yep, this is a libvirt bug. There's a fix here:

https://www.redhat.com/archives/libvir-list/2019-April/msg00876.html

BTW: are you running libvirt inside a container perhaps? Or without capng?

Michal