[REGRESSION] fdo bug 86565 - black screen after resume from hibernation since linux kernel 3.18

[Martin Steigerwald <martin@lichtvoll.de>]

Hi!

I reported this with fdo for intel drivers back then as

https://bugs.freedesktop.org/86565

as I thought it to likely be an intel driver bug.


As it still happens and I am not sure of that anymore, I report here as 
well. I still CC intel gfx list as well, as I didn´t get a comment on the 
debug log I attached to the bug report till now.


Since linux kernel 3.18-rc2 I sometimes get a black screen after resuming 
from hibernation via in-kernel-suspend. With 3.17 I didn't have this 
issue. Additionally, sometimes on hibernation the machine after writing 
the image does not switch off, but stays on with the power LED blinking. I 
then usually switch it off manually by pressing power button longer and it 
usually resumes just fine after it.

The first issue is most annoying and it seems they are unrelated, cause as 
I found now, the first issue happens even if the second one didn´t happen 
before. When the screen is black it takes some minutes usually and then  
it displays the lock screen again. As it doesn´t happen on every resume 
from hibernation and it may work okay for five or more attempts, bisecting 
this likely would take ages.

This is with a ThinkPad T520 with BIOS Version: 8AET63WW (1.43 ), Release 
Date: 05/08/2013. The black screen happens with 3.18-rc2 upto 3.19-rc7. 
With Intel Sandybridge graphics (no nvidia optimus).


I think it may be more of a general PM management issue, as I now heard 
the the laptop was making the usual resume audio signal *after* the black 
screen delay. Thus I thought it may be stuck in general resume.


In comment #8 I attached a debug log with no_console_suspend drm.debug=0xe 
initcall_debug as being asked for:

https://bugs.freedesktop.org/show_bug.cgi?id=86565#c8


I didn´t yet receive any comment on this.

Any further ideas?


If not I will test with 3.20-rc2 again and also try the patch Jani 
mentioned in comment #7 in case its not in there.

Thanks,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7