Dear Ruediger,

Am Thu, Nov 06, 2025 at 01:56:54PM +0100 schrieb H.-R. Oberhage:
> The problem here most probably are the PV (paravirtualized) VMs.
> There is no "spice" option available for it, to my dismay, so
> I'm stuck with VNC as display device and the "video" is "xen".

I experimented a bit with different display options here. For me
VNC display worked at least with qemu. Can you post the output
when starting a vm from cmd like so:

$ virsh -d0 -c qemu:///system start devuan-daedalus
start: domain(optdata): devuan-daedalus
start: found option <domain>: devuan-daedalus
start: <domain> trying as domain NAME
error: Failed to start domain 'devuan-daedalus'
error: internal error: process exited while connecting to monitor: 2025-11-12T20:10:32.687041Z qemu-system-x86_64: warning: This feature depends on other features that were not requested: CPUID.8000000AH:EDX.flushbyasid [bit 6]
2025-11-12T20:10:32.687042Z qemu-system-x86_64: warning: This feature depends on other features that were not requested: CPUID.8000000AH:EDX.pause-filter [bit 10]
2025-11-12T20:10:32.687044Z qemu-system-x86_64: warning: This feature depends on other features that were not requested: CPUID.8000000AH:EDX.pfthreshold [bit 12]
2025-11-12T20:10:32.687045Z qemu-system-x86_64: warning: This feature depends on other features that were not requested: CPUID.8000000AH:EDX.vgif [bit 16]
2025-11-12T20:10:32.695765Z qemu-system-x86_64: -device {"driver":"virtio-vga-gl","id":"video0","max_outputs":1,"bus":"pcie.0","addr":"0x1"}: The display backend does not have OpenGL support enabled
It can be enabled with '-display BACKEND,gl=on' where BACKEND is the name of the display backend to use.

(This was output with a intentionally bad config) I assume
you have to use "xen:///system" instead for connect uri.

I currently have no xen machine for further tests here,
maybe I have to prepare it.

Best regards,
Andreas

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