Bug 115251

Summary: amdgpu: Black screen + hang with Kaveri
Product: Drivers Reporter: Bernd Steinhauser (linux)
Component: Video(DRI - non Intel)Assignee: drivers_video-dri
Status: RESOLVED CODE_FIX    
Severity: normal CC: alexdeucher
Priority: P1    
Hardware: x86-64   
OS: Linux   
Kernel Version: 4.4.5 Subsystem:
Regression: No Bisected commit-id:
Attachments: Xorg log
fix for 4.5

Description Bernd Steinhauser 2016-03-24 19:40:36 UTC 
Created attachment 210661 [details]
Xorg log

With 4.4.6, I noticed I cannot use the xf86-video-amdgpu ddx anymore.
When the X server starts, the screen will go black, in the log, there is a message telling me that the device initialization failed.
I can't get the console back either, but emergency sync, ro remount and poweroff do work.
Before starting X, the driver seems to work fine, only when starting X things go wrong.
The issue is present with 4.5.0 as well.
Will upload a Xorg log, but it won't be much of a help, because it seems to be cut off, even though I waited for a long time before sync and unmount.
Also tried to capture dmesg, but got only a partial one as well which was cut off before things got interesting.

bisect led to (on the 4.4.y branch):

a46a700abc520bfadf5fa1cc371ba07d6d7f9230 is the first bad commit
commit a46a700abc520bfadf5fa1cc371ba07d6d7f9230
Author: Christian König <christian.koenig@amd.com>
Date:   Fri Feb 26 16:18:15 2016 +0100

    drm/amdgpu: apply gfx_v8 fixes to gfx_v7 as well
····
    commit feebe91aa9a9d99d9ec157612a614fadb79beb99 upstream.
····
    We never ported that back to CIK, so we could run into VM faults here.
····
    Signed-off-by: Christian König <christian.koenig@amd.com>
    Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

:040000 040000 3930bee60c2e64b348ee8e5f618326b5f6141cdc 8501edda2a7d8ee201cde839ac01d943bec84a51 M      drivers

Reverting that commit on top of 4.4.6 (or the corresponding one on top of 4.5.0) gets things working again.
Comment 1 Alex Deucher 2016-03-24 19:52:53 UTC 
Created attachment 210671 [details]
fix for 4.5

The fix for 4.5 has already gone to stable, it just hasn't been applied yet.  4.6 is not affected.
Comment 2 Bernd Steinhauser 2016-03-26 07:59:10 UTC 
Thanks, that works.
Comment 3 Bernd Steinhauser 2016-04-21 04:55:52 UTC 
Ping.

Was this forgotten? Afaics, it's still not applied to 4.5 stable (in 4.5.2).
Comment 4 Alex Deucher 2016-04-21 13:52:31 UTC 
Greg still hasn't applied it.
Comment 5 Bernd Steinhauser 2016-06-03 05:19:08 UTC 
Fixed with v4.5.3 or more specific commit a287c7.