Display turn off when switching workspace

[X512]

This is hrev53713 x86 gcc2hybrid.

Steps to reproduce:

1. Switch to 3-rd workspace.
2. Display will turn off.

Switching back to 1-st workspace don't help.

Used driver: intel_extreme Video adapter:

device Display controller (VGA compatible controller, VGA controller) [3|0|0]
  vendor 8086: Intel Corporation
  device 0412: Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller

[diver]

Could it be that you have some custom resolution on the 3rd workspace from which intel_extreme driver can't recover?

[X512]

Seems fixed after reapplying display settings on all workspaces. Anyway driver should not allow set mode that makes display unusable until reboot.

[diver]

I wonder why switching back to the 1st workspace didn't change the resolution back.

[pulkomandy]

Replying to diver:

I wonder why switching back to the 1st workspace didn't change the resolution back.

Because the modesetting code puts the display in a completely invalid state when this happens, and does not know how to reset it properly.

"Good" news is I can reproduce this on my main machine.

[pulkomandy]

No syslog here, but there was one for a similar case attached to #15628 where we can see this:

intel_set_display_mode(14947x24936)

This is the input from app_server, so I think something is wrong on app_server side for this one.

[pulkomandy]

I have intentionally put this ticket in the generic "intel_extreme" component because it affects other devices too. What happens is on update, the screenmode settings end up being ignored or misinterpreted somehow and the workspaces get invalid video modes. It does not seem to be specific to the hardware, more that the driver fails to sanitize video modes properly in general.

[modeenf]

ah sorry..