Bug 43231

Summary: black screen on sonyvaio vpccw1
Product: ACPI Reporter: Marco Bo (black_painkiller)
Component: Power-VideoAssignee: Zhang Rui (rui.zhang)
Status: CLOSED CODE_FIX    
Severity: normal CC: emil.l.velikov, kvs, lenb
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.4 Subsystem:
Regression: Yes Bisected commit-id:

Description Marco Bo 2012-05-11 17:39:21 UTC 
https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-nouveau/+bug/984866

I though it was a nouveau problem but they told me it's from ACPI.
Also, on 3.3 backlight is reported as software , on 3.4 kernel thinks it is hardware and so nouveau does not enable control over it
Comment 1 Len Brown 2012-05-15 02:18:11 UTC 
so 3.3.4 works and 3.4 fails?
can you bisect which commit caused the failure?
Comment 2 Marco Bo 2012-05-21 07:50:45 UTC 
I'm not able to do that, sorry.
Comment 4 Vlad K 2012-06-06 07:41:58 UTC 
This does appear to be a bug in drivers/acpi/video.c likely from commit ea9f8856bd6d4ed45885b06a338f7362cd6c60e5 as mentioned in other bug report. I was able to copy video.c from 3.3.6 branch and system booted no problem. Also I booted fine with "nomodeset" option and manually inserted nouveau, which produced these messages in kern.log: http://pastebin.com/3D3UZiw8
Comment 5 Vlad K 2012-06-07 20:30:14 UTC 
After further testing it seems my previous comment is unrelated to this bug.
Comment 6 Marco Bo 2012-06-07 20:37:17 UTC 
i reverted the version of drivers/acpi/video.c before that commit and recompile the kernel and it works.
did you mean the second part of your comment?
Comment 7 Vlad K 2012-06-07 21:29:24 UTC 
yeah, after bisecting it appears to be a different regression in drm (43353).
Comment 8 Marco Bo 2012-06-19 20:57:41 UTC 
dublicate of https://bugs.freedesktop.org/show_bug.cgi?id=50175.

in comments there the patch
https://bugzilla.kernel.org/attachment.cgi?id=73576

that fixes it!
Comment 9 Emil Velikov 2012-06-24 21:50:26 UTC 
Vlad K

Copying files accross different kernel versions is a bad idea. Please consider reverting the commit in the future

Furthermore according to your dmesg you're experiencing another issue bug 43353

To the original reporter - the issue has been reported on freedesktop.org bug 5017 as well as kernel.org bug 43168, although it is an ACPI in nature

Consider closing the bug as a duplicate of bug 43168, as per original report
Comment 10 Zhang Rui 2012-11-13 07:47:58 UTC 
Patch in bug #43168 has been shipped in upstream linux kernel.

please reopen the bug report if the problem still exists.