Bug 1227770 - Gdm doesn't show up in qemu environment with cirrus graphics card (KVM or Xen)
Summary: Gdm doesn't show up in qemu environment with cirrus graphics card (KVM or Xen)
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Fedora
Classification: Fedora
Component: wayland
Version: 24
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: ---
Assignee: Adam Jackson
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2015-06-03 13:04 UTC by Göran Uddeborg
Modified: 2016-12-19 20:31 UTC (History)
7 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2016-12-19 20:31:14 UTC
Type: Bug
Embargoed:


Attachments (Terms of Use)

Description Göran Uddeborg 2015-06-03 13:04:19 UTC
Description of problem:
After upgrading a virtual machine from Fedora 21 to 22 the login console didn't show up.  The fedora "F" logo remained in place.  The machine was configured to use the "cirrus" graphics card.

I activated the "WaylandEnable=false" line in /etc/gdm/custom.conf.  Then the login screen did show up again.

I switched back by commenting out the line again, but switched to a "qxl" graphics card in virt-manager.  The gdm login screen did show up again.

So the problematic combination appears to be wayland on cirrus.

Version-Release number of selected component (if applicable):
I'm not sure what component is to blame, I haven't really understood wayland yet.  But here are a couple of version numbers that might be relevant.
gdm-3.16.1.1-1.fc22.x86_64
xorg-x11-server-Xwayland-1.17.1-12.fc22.x86_64
libwayland-client-1.7.0-1.fc22.x86_64
gnome-session-wayland-session-3.16.0-1.fc22.x86_64


How reproducible:
Every time

Steps to Reproduce:
1. Configure a virtual machine with an cirrus graphics card.
2. Try to run Fedora 22 with gdm on it.

Actual results:
The "F" from the boot stays on the console screen.

Expected results:
A gdm login screen should show up.

Additional info:
The host system is RHEL6, in case that matters.

Comment 1 Seth Jennings 2015-09-22 15:25:21 UTC
Still a problem in F23 as well.

Comment 2 Fedora End Of Life 2016-07-19 14:36:18 UTC
Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.

Comment 3 Göran Uddeborg 2016-07-19 19:42:18 UTC
I haven't tried recently myself, but Seth reported in comment 1 the problem remains in F23.

Comment 4 Seth Jennings 2016-07-21 19:58:45 UTC
Still the case in F24 as well

Comment 5 Dario Faggioli 2016-11-18 16:47:06 UTC
Hi,

I've just tried installing Fedora 25 Beta both as a KVM and Xen (HVM) guest, and I see exactly the same. That's probably totally expected, as both uses qemu as graphic backend.

Install (via the netinstall iso) goes just fine.

Then, with Wayland enabled and Cirrus as emulated graphic card, I don't see the login screen appearing, neither under Xen nor under KVM.

If I keep Cirrus and disable Wayland (via /etc/gdm/custom.conf), both Xen and KVM guests works ok.

If I keep wayland and use a different graphic card (vga or qxl, for instance), both Xen and KVM guests works ok.

Regards,
Dario

Comment 6 Konrad Rzeszutek Wilk 2016-11-18 16:47:06 UTC
Ditton Fedora 25.

Comment 7 Gerd Hoffmann 2016-11-21 09:23:37 UTC
Most likely this is wayland not supporting 24bpp.
No easy way out with cirrus as we mimic existing hardware.

cirrus offers zero advantages over vga, except for old guests.  With "old" as in same-age-as-physical-cirrus-hardware, i.e. stuff designed in the 90ies, which might find the cirrus 2d bitops useful.

So, just use vga and be happy.

verbose version:
https://www.kraxel.org/blog/2014/10/qemu-using-cirrus-considered-harmful/

Comment 8 Konrad Rzeszutek Wilk 2016-11-21 15:25:37 UTC
Gerd,

Please don't just close the bug b/c 'likely' there is an issue. T

Lets figure out the technical parts of the issue. Perhaps Adam can share some clues on how to figure out what is going wrong, and what we can report and look for?

Independently of that if cirrus is not the way forward then work should be done to make sure that libvirt will pick the default stdvga instead of cirrus (both for Xen and KVM).

Comment 9 Gerd Hoffmann 2016-11-21 16:27:43 UTC
> Please don't just close the bug b/c 'likely' there is an issue.

Well, I would be *seriously* surprised if it is something else.  cirrus being pretty much the only hardware still using 24bpp (at the 1024x768 default resolution) leads to problems since years.  There are (have been?) xorg rendering bugs showing up on cirrus only because of this.

> Lets figure out the technical parts of the issue. Perhaps Adam can share
> some clues on how to figure out what is going wrong, and what we can report
> and look for?

You can try whenever wayland runs @ 800x600.
That is the largest resolution cirrus supports 32bpp at.

> Independently of that if cirrus is not the way forward then work should be
> done to make sure that libvirt will pick the default stdvga instead of
> cirrus (both for Xen and KVM).

qemu switched the default a while back (2.2 IIRC).

A bunch of other management tools followed upstream qemu behavior,
I don't have an overview on the current state of all the tools though.

Feel free to file bugs if you find tools still using cirrus by default
for new installs.  You can throw the link to the blog post at them ;)

Comment 10 Gerd Hoffmann 2016-11-21 18:10:01 UTC
(In reply to Gerd Hoffmann from comment #9)
> > Please don't just close the bug b/c 'likely' there is an issue.
> 
> Well, I would be *seriously* surprised if it is something else.

To correct myself:  Could also be that wayland can't pageflip, due to cirrus not having enough video memory for two framebuffers.  Or the kernel driver lacks pageflipping support.  Or both.

Which at the end of they day boils down to the same thing though:
cirrus (virtual) hardware is simply to old to run wayland.

Comment 11 Göran Uddeborg 2016-12-19 20:31:14 UTC
I read Gerd's comments as still saying this won't be fixed.  He/you didn't close the bug again, but I guess that was an oversight.  I'm putting it to rest.


Note You need to log in before you can comment on or make changes to this bug.