[SOLVED] Black screen with virt-manager

YourPadre · 11-29-2013, 08:01 PM

Hi

I have a server OpenSuse 12.3 x64 with libvirt 1.0.2-1.3.1 and somes VM.

Before I managed the VM's using virt-manager 0.9.4 with slackware 14.0.

Now with slackware 14.1 and the recent slackbuild file for virt-manager 0.10.0, when I open a VM only appear a black screen, or rarely in the top of the window a small part of the VM's "monitor".

The VM's uses Video cirrus and Monitor VNC.

Any idea?

Richard Cranium · 11-30-2013, 01:12 PM

I haven't had any problems with qxl drivers and spice-gtk. That with RedHat 6.4 and Kubuntu 13.whatever clients.

Melville · 12-01-2013, 05:22 AM

I can confirm it and reproduce, but it is issue with qemu and not virt-manager. It affects only one display backend: gtk (has nothing to do with chosen vga). Example:

Code:

$ qemu-kvm -cdrom some-linux-distro.iso

Will give blank/black screen, because by default "-display gtk" is used. On other hand:

Code:

$ qemu-kvm -display sdl -cdrom some-linux-distro.iso

Works just fine (not sure how to set that in virt-manager, because I don't use it). Not sure what is the issue. Doesn't affect me, because I use spice output anyway. Downgrading qemu for the start probably would help pinpointing this problem (checking if gtk display is also not working on Slackware 14.1 in previous versions of qemu).

YourPadre · 12-01-2013, 06:50 PM

Quote:

Originally Posted by Melville

Works just fine (not sure how to set that in virt-manager, because I don't use it). Not sure what is the issue. Doesn't affect me, because I use spice output anyway. Downgrading qemu for the start probably would help pinpointing this problem (checking if gtk display is also not working on Slackware 14.1 in previous versions of qemu).

I don't know how work virt-manager too but I thougth that it was connecting to qemu-kvm at the OpenSuse server and using VNC to see the "screen" in my computer, so I don't see any reason to downgrade qemu-kvm because it is the same version, the only difference is slackware, from 14 to 14.1.

I'll install slackware (both 14 and 14.1) in a VM using a local vmware player (inside of my current slackware 14.1) to make some test.

Melville · 12-02-2013, 03:36 AM

Quote:

Originally Posted by YourPadre

I don't know how work virt-manager too but I thougth that it was connecting to qemu-kvm at the OpenSuse server and using VNC to see the "screen" in my computer, so I don't see any reason to downgrade qemu-kvm because it is the same version, the only difference is slackware, from 14 to 14.1.

I'll install slackware (both 14 and 14.1) in a VM using a local vmware player (inside of my current slackware 14.1) to make some test.

If I understand OpenSuse is a host and Slackware guest inside VM? That wasn't 100% clear in previous post.

YourPadre · 12-02-2013, 10:27 PM

Quote:

Originally Posted by Melville

If I understand OpenSuse is a host and Slackware guest inside VM? That wasn't 100% clear in previous post.

No.
a) OpenSuse is the host. Here runs qemu-kvm.
b) Slackware has virt-manager. It manages the host and connects to VM using VNC to "see" the VM screen.
c) The VM are windows and linux.

With Slackware (point b), I used the version 14 before and the VNC works. Now with v14.1 it doesn't works the VNC.

xj25vm · 12-03-2013, 02:34 AM

I can confirm that I'm having the same problem. I'm using Slackware 14.1 as host, Windows XP as guest. SDL and VNC displays work fine, GTK doesn't. I'm using qemu directly on the command line.

GPLeChuck · 12-03-2013, 06:06 AM

Hi guys,

Having the same issue with the black screen after upgrading libvirt, qemu, virt-manager and related packages from the 14.1 Slackbuilds...

Same thing when connecting to existing guest VMs using virt-viewer.

The VMs and libvirt\qemu are fine, I can connect to guests over SSH. I think Melvilles right that its the display backend thats an issue here. If I create a new VM, it displays OK in the virt-manager console. Not at my home computer right now so can't confirm, but I bet comparing the qemu ps output from a blank VM and a newly added VM would show the difference.

Maybe the domain XML files for the old guest VMs can be edited to change the parameters that qemu boots them with, but haven't looked into this yet.

xj25vm · 12-03-2013, 08:16 AM

I should mention that the gtk display doesn't work for a freshly installed Windows XP guest vm for me - a vm which has been created from scratch on Slackware 14.1 host

GPLeChuck · 12-03-2013, 12:39 PM

UGH sincere apologies, the black screen persists for new VMs also. I started to create a new VM previously, to test, and the installation screen appeared in the console, so I thought all was well with the display and stopped the installation - as I didn't need a new VM for any other reason.

Just had a quick look, and worked around it by using SPICE. Tried this for one of the guest VMs and it worked OK.

http://www.linux-kvm.org/page/SPICE

In virt-manager, set the video model to QLX and the display type to SPICE
I had SSH access to the guest, so logged in and installed spice-vdagent

After a reboot, I can access the guest VM using spice client : spicec -h 127.0.0.1 -p 5900

Hope this helps

YourPadre · 02-06-2014, 10:45 PM

Today, February 6, the problem was fixed after run "sbopkg update" and install all virt-manager related packages.

Thanks to the persons who work in the slackbuild files.

willysr · 02-06-2014, 11:17 PM

Actually the problem was fixed with cairo update in 14.1 and current

xj25vm · 02-16-2014, 11:15 AM

Quote:

Originally Posted by willysr

Actually the problem was fixed with cairo update in 14.1 and current

Yes, thanks for that. I confirm that updating cairo from 1.12.14 to 1.12.16 one Slack 14.1 64bit has re-enabled the sdl output.