Bug 202799

Summary: amd/dc: right monitor sometimes never comes back up on dual-display setup after locking session
Product: Drivers Reporter: Clément Guérin (libcg)
Component: Video(DRI - non Intel)Assignee: drivers_video-dri
Status: RESOLVED OBSOLETE    
Severity: normal CC: harry.wentland, nicholas.kazlauskas
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 5.0 Subsystem:
Regression: No Bisected commit-id:
Attachments: xrandr --props output
dmesg output
Xorg.1.log
dmesg drm.debug=4

Description Clément Guérin 2019-03-07 02:20:56 UTC
Created attachment 281547 [details]
xrandr --props output

- linux 5.0 (4.20 also had the same issue)
- xf86-video-amdgpu 18.1.0
- GNOME 3.30

Left screen is a Dell U2412M (1920x1200), right screen is a Dell P2715Q (4K monitor set at 2560x1440, primary). GPU is RX 580.

Steps to reproduce:
- Lock session, screens turn off
- After a while, press a key to turn the screens back on again
- When the left screen lights up first, the system only displays an image on the left screen. The right screen lights up afterwards but goes back to sleep because it's getting no signal, although xrandr still recognizes it.  I need to manually turn off the right screen and back on again to get it to reconfigure.

When using `amdgpu.dc=0`, this issue disappears.
Comment 1 Michel Dänzer 2019-03-07 09:19:01 UTC
Please attach the corresponding Xorg log file and full output of dmesg, preferably captured after the problem occurred.
Comment 2 Clément Guérin 2019-03-07 21:21:10 UTC
Created attachment 281577 [details]
dmesg output
Comment 3 Clément Guérin 2019-03-07 21:27:03 UTC
Created attachment 281587 [details]
Xorg.1.log

Logs after the bug was triggered.
Comment 4 Clément Guérin 2019-03-13 22:02:15 UTC
Hi Michel, is there anything else you need to debug this?
Comment 5 Michel Dänzer 2019-03-14 08:56:09 UTC
I have to defer to the DC guys in the CC list.
Comment 6 Nicholas Kazlauskas 2019-03-14 13:14:57 UTC
It might be useful to have a dmesg log from after the problem occurred with drm.debug=4 set in your kernel boot parameters.
Comment 7 Clément Guérin 2019-03-15 22:00:09 UTC
Created attachment 281855 [details]
dmesg drm.debug=4

Here's the log as requested.
Comment 8 Clément Guérin 2019-03-28 03:47:31 UTC
Do you need anything else?
Comment 9 Clément Guérin 2019-05-10 20:15:26 UTC
I'm still seeing this bug with linux 5.1.
Comment 10 Clément Guérin 2019-07-09 23:04:22 UTC
This is still a problem on Linux 5.2.
Comment 11 Clément Guérin 2020-02-15 22:44:17 UTC
I switched to wayland months ago and haven't hit that bug since.