[fedora-virt] [Fedora-xen] Fedora 17 testing as Xen VM / Xorg issue

[Pasi Kärkkäinen]

On Tue, May 29, 2012 at 11:15:52AM -0400, Konrad Rzeszutek Wilk wrote:
> On Mon, May 28, 2012 at 10:45:37PM +0300, Pasi Kärkkäinen wrote:
> > Hello,
> > 
> > I just did some installs with F17 RC4 (the GA version) as a Xen VM.
> > 
> > Xen host/dom0: RHEL 5.8 x86_64 with the included Xen rpms.
> > 
> > Tested F17 RC4 VMs:
> > 
> > 	- 32bit F17 PV domU: graphical GUI install works OK using the Xen vfb/pvfb
> > 	  but Xorg fails to start during normal boot after installation.
> > 
> > 	- 64bit F17 PV domU: graphical GUI install works OK using the Xen vfb/pvfb 
> > 	  but Xorg fails to start during normal boot after installation.
> > 
> > 	- 32bit F17 PVHVM guest: X fails to start so VNC install must be used, install works OK thru VNC. 
> > 	  Xorg fails to start during normal boot after installation.
> > 
> > 	- 64bit F17 PVHVM guest: X fails to start so VNC install must be used, install works OK thru VNC. 
> > 	  Xorg fails to start during normal boot after installation.
> > 
> > (PVHVM == HVM fully virtualized guest with optimized Xen PV drivers.
> > Optimized Xen PVHVM drivers are nowadays included and used as a default with 
> > recent upstream Linux kernel versions (2.6.36+), so disk/net IO doesn't have to be emulated by Xen Qemu-dm.)
> > 
> > I wonder if the problem with X failing to start is related to:
> > http://fedoraproject.org/wiki/Features/DRI2DriversOnly
> > 
> > Xen HVM guests have Qemu-dm emulated Cirrus VGA adapter (or stdvga) visible to the VM.. 
> > which doesn't have DRM/KMS drivers, and I think it's the same for xen-fbfront. 
> > I think I saw Cirrus (Qemu) DRM/KMS driver being worked on dri-devel mailinglist.. 
> 
> You are hitting https://bugzilla.redhat.com/show_bug.cgi?id=810040 I think.
> 

Yes, that was the problem with F17 PV domUs! After I remove fprintd and fprintd-pam rpms
GDM works OK on the Xen pvfb and I can login to the desktop.


However there's a different problem with F17 HVM guests. There Xorg doesn't start at all.
"X startup failed, falling back to text mode" when I try to boot the F17 DVD installer .iso.
Also "Starting Show Plymouth Boot Screen..." is [FAILED].

When I run "X" manually from the console I get this in Xorg.0.log:

LoadModule: "xaa"
Warning, couldn't open module xaa
UnloadModule: "xaa"
Unloading: xaa
CIRRUS: Failed to load module "xaa" (module does not exist, 0)
UnloadModule: "cirrus"
..
Fatal server error:
no screens found
..
Server terminated with error (1).


So it looks like Xorg requires xaa module for cirrus, but it's not there anymore.
I guess this is related to the DRI2Only-feature in F17 ?

http://fedoraproject.org/wiki/Features/DRI2DriversOnly


-- Pasi