Bug 1008312

Created attachment 798117 [details]
The screenshot for guest

Created attachment 798118 [details]
The screenshot for host

Created attachment 798120 [details]
The virt-viewer log file

please provide the xrandr of host (and guest when in fullscreen could be eventually helpful too)

Created attachment 799090 [details]
host_xrandr

Created attachment 799091 [details]
guest xrandr

Help condong providing the host and guest xrandr information which Marc-Andre required.
The guest xrandr is get when in fullscreen status.

I haven't been able to reproduce this here.  It would help if you provided *exact* steps to reproduce this from beginning to end. In other words: instead of saying "Change to Fullscreen mode", describe the exact method you used to do this via clicking on UI elements, etc. This helps reduce any ambiguity and might allow developers to reproduce it on our machines.

Also, thanks for the xrandr output.  Unfortunately, it's a bit hard to draw any conclusions from it for a couple of reasons:

1) the xrandr output doesn't appear to match the screenshots above
2) the guest xrandr output doesn't appear to show any display overlap

It would be nice to have xrandr output and screenshots from the exact same test run so that they're comparable.

Sorry for the confusing steps, make it clear here:

Steps:
1. Prepare a rhel6 guest on a 4 monitors host, with spice+qxl(one) + spicevmc + 4 displays
2. virt-viewer $vm 
3. Open 4 displays, move each display to the corresponding physical monitor and press "F11" to change the display to full-screen mode. Check the resolution.
4. Save the screenshot in guest and host, check them.

The xrandr message is not very long, add here:

On host:
# xrandr
Screen 0: minimum 320 x 200, current 5520 x 1050, maximum 16384 x 16384
DisplayPort-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+   75.0  
   1152x864       75.0  
   1024x768       75.1     60.0  
   800x600        75.0     60.3  
   640x480        75.0     60.0  
   720x400        70.1  
HDMI-0 connected 1280x1024+1280+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+   75.0  
   1152x864       75.0  
   1280x720       50.0     60.0  
   1024x768       75.1     60.0  
   800x600        75.0     60.3  
   720x480        59.9  
   640x480        75.0     60.0  
   720x400        70.1  
DVI-0 connected 1680x1050+2560+0 (normal left inverted right x axis y axis) 474mm x 296mm
   1680x1050      60.0*+   74.9  
   1600x1000      60.0  
   1280x1024      75.0     72.0     60.0  
   1440x900       75.0     59.9  
   1152x864       75.0  
   1024x768       75.1     70.1     60.0  
   800x600        72.2     75.0     60.3  
   640x480        72.8     75.0     66.7     60.0  
   720x400        70.1  
DVI-1 connected 1280x1024+4240+0 (normal left inverted right x axis y axis) 376mm x 301mm
   1280x1024      60.0*+   75.0  
   1152x864       75.0  
   1024x768       75.1     60.0  
   800x600        75.0     60.3  
   640x480        75.0     60.0  
   720x400        70.1

On guest:
# xrandr
Screen 0: minimum 320 x 200, current 2560 x 1024, maximum 8192 x 8192
qxl-0 connected 1280x1024+0+0 0mm x 0mm
   1024x768       60.0 +
   2560x1600      60.0  
   2000x2000      60.0  
   2560x1440      60.0  
   2048x1536      60.0  
   1920x1440      60.0  
   1920x1200      60.0  
   1920x1080      60.0  
   1600x1200      60.0  
   1680x1050      60.0  
   1400x1050      60.0  
   1600x900       60.0  
   1280x1024      60.0* 
   1440x900       60.0  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       60.0  
   1152x870       60.0  
   1152x864       60.0  
   1280x768       60.0  
   1280x760       60.0  
   1280x720       60.0  
   1024x600       60.0  
   960x640        60.0  
   832x624        60.0  
   800x600        60.0  
   800x480        60.0  
   640x480        60.0  
qxl-1 connected 1280x1024+1280+0 0mm x 0mm
   1024x768       60.0 +
   2560x1600      60.0  
   2000x2000      60.0  
   2560x1440      60.0  
   2048x1536      60.0  
   1920x1440      60.0  
   1920x1200      60.0  
   1920x1080      60.0  
   1600x1200      60.0  
   1680x1050      60.0  
   1400x1050      60.0  
   1600x900       60.0  
   1280x1024      60.0* 
   1440x900       60.0  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       60.0  
   1152x870       60.0  
   1152x864       60.0  
   1280x768       60.0  
   1280x760       60.0  
   1280x720       60.0  
   1024x600       60.0  
   960x640        60.0  
   832x624        60.0  
   800x600        60.0  
   800x480        60.0  
   640x480        60.0  
qxl-2 connected 400x375+1424+0 0mm x 0mm
   1024x768       60.0 +
   2560x1600      60.0  
   2000x2000      60.0  
   2560x1440      60.0  
   2048x1536      60.0  
   1920x1440      60.0  
   1920x1200      60.0  
   1920x1080      60.0  
   1600x1200      60.0  
   1680x1050      60.0  
   1400x1050      60.0  
   1600x900       60.0  
   1280x1024      60.0  
   1440x900       60.0  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       60.0  
   1152x870       60.0  
   1152x864       60.0  
   1280x768       60.0  
   1280x760       60.0  
   1280x720       60.0  
   1024x600       60.0  
   960x640        60.0  
   832x624        60.0  
   800x600        60.0  
   800x480        60.0  
   640x480        60.0  
   400x375-2       0.1* 
qxl-3 connected 400x375+1824+0 0mm x 0mm
   1024x768       60.0 +
   2560x1600      60.0  
   2000x2000      60.0  
   2560x1440      60.0  
   2048x1536      60.0  
   1920x1440      60.0  
   1920x1200      60.0  
   1920x1080      60.0  
   1600x1200      60.0  
   1680x1050      60.0  
   1400x1050      60.0  
   1600x900       60.0  
   1280x1024      60.0  
   1440x900       60.0  
   1280x960       60.0  
   1366x768       60.0  
   1360x768       60.0  
   1280x800       60.0  
   1152x870       60.0  
   1152x864       60.0  
   1280x768       60.0  
   1280x760       60.0  
   1280x720       60.0  
   1024x600       60.0  
   960x640        60.0  
   832x624        60.0  
   800x600        60.0  
   800x480        60.0  
   640x480        60.0  
   400x375-3       0.1*

Created attachment 826934 [details]
new screenshot  in guest

Created attachment 826935 [details]
new screenshot  in host

Thanks.  I'm seeing rather strange behavior with 4 displays here as well.  Investigating...

hm, perhaps the strange behavior I'm seeing is slightly different than yours. Can I ask you to get the spice debug output?

virt-viewer --debug --spice-debug $vm

Comment 3 is the log file with spice debug option.

hm, I notice that in the log, after maximizing the last display, the server sends a new MONITORS_CONFIG message with the larger size, but the x-coordinate position of the display makes it so that it does nto intersect the primary canvas that the spice client has for the display channel.  Soon thereafter, the server sends another MONITORS_CONFIG message reverting back to the old size/position for the last monitor.  The same thing happens to the third display.  I still don't understand exactly why the resolution is reverting back to the old size, but I'll continue investigating.

The fix that was recently applied upstream for bug #1002156 should reduce the impact of the bug slightly though, by preventing overlap between display regions.

Talking with Hans, it seems that this is mostly likely a configuration issue rather than a bug.  What is your QXL memory set to?  The default is 64MB, which is apparently known to be insufficient for 4 displays.  Can you try to increase your qxl memory to 128MB or 256MB and see if this fixes the issue.  You can use 'virsh edit $vmname' and change the qxl memory to something like:

<model type='qxl' ram='131072' vram='131072' heads='1'/>

The default is 64MB, and I tested as you said, increase the memory to 128MB

<model type='qxl' ram='131072' vram='131072' heads='1'/>

The problem still can be reproduced,and then I increase the memory to 256MB, can reproduce too.

*** Bug 1034397 has been marked as a duplicate of this bug. ***

*** Bug 1052328 has been marked as a duplicate of this bug. ***

Re-assigning to qxl based on the following conversation, apologies for the delay:

http://lists.freedesktop.org/archives/spice-devel/2013-December/015658.html
http://lists.freedesktop.org/archives/spice-devel/2013-December/015659.html

There are two bugs / issues here, IMHO.

1) Not enough memory for framebuffer in qxl causes the resolution of additional monitors to "shrink" after configuration.  The fix in comment#18 MAY be necessary, but is not sufficient to fix this issue, because the default 16MB is still in effect until you edit the domain XML ("virsh edit myvm")

a. In the <domain> element (at the top), add the attribute:
 xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'

b. Add the following:
  <qemu:commandline>
    <qemu:arg value='-global'/>
    <qemu:arg value='qxl-vga.vgamem_mb=32'/>
  </qemu:commandline>

Maybe the default value should be changed or calculated dynamically based on the "ram" or "vram" configuration.

2) The issue where the second "monitor" shows a combined view of two of the other monitors (part two of the "actual" issue) is "fixed" (according to me as author of the fix ;-) by this commit in the linux kernel which has been merged into Linus's tree for inclusion in release 3.16:

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=52571ad5f4c57067ac593a6bdb1f7a35ed032d27

See upstream bug: 
https://bugs.freedesktop.org/show_bug.cgi?id=78131

(Note: this part of the bug is not necessarily triggered on GNOME3 because of some lucky ordering of ioctl during monitor resizing).

One more note: It may be that the underlying configuration option "-global qxl-vga.vgamem_mb=32" may not be supported in rhel6, and only works in rhel7/fedora so the 16MB framebuffer limit may be impossible to pass without re-compiling...

This limitation is referenced in the second message linked in comment#22.

In that message, the suggestion that the increased FB allocation be tied to the memory reservation  (e.g. ram='131072' vram='131072' should imply a 32MB framebuffer instead of 16mb) seems to be the recommended approach.

it's tempting to close as duplicate of bug 1076728, adding dep

CongDong, can you still reach the mirror display bug?

To reach higher resolution, bug 1053039 provides a mean to configure the maximum framebuffer size.

I cannot reproduce this with the latest pkg and os.

But if I downgrade xorg-x11-drv-qxl to old version like 0.1.1-9.el6,
then I can reproduce this.

thanks