Bug 94933

Summary: [RV610] Freeze when turning on an external monitor after resume from suspend
Product: DRI Reporter: Nicola Mori <nicolamori>
Component: DRM/RadeonAssignee: Default DRI bug account <dri-devel>
Status: RESOLVED MOVED QA Contact:
Severity: normal    
Priority: medium CC: nicolamori
Version: unspecified   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
dmesg
none
Xorg.0.log
none
dmesg on screen resize
none
Xorg.0.log for screen resize none

Description Nicola Mori 2016-04-14 15:38:21 UTC 
I have a laptop with a Mobility Radeon HD3470 (RV610) and Plasma 5.6.2 as desktop environment. After suspending to RAM and resuming, I experience a system freeze when trying to switch to a dual monitor setup using an external monitor connected to the VGA output. The dual monitor can be turned on without problems before the suspend/resume cycle.
I don't know which logs/information could be useful to diagnose the problem, so I will provide it on demand. Thanks.

System details
--------------
VGA: Mobility Radeon HD3470 (RV610)
OS: ArchLinux 64 bit, kernel 4.4.7, xf86-video-ati 7.7.0
Desktop: Plasma 5.6.2 (with KF5 5.21 and Qt 5.6.0)

Steps to reproduce
------------------
- Start the system with only the laptop panel turned on
- Suspend to RAM and then resume
- Connect an external monitor
- Enable the external monitor with xrandr or with the KCM module (System settings -> Display and Monitor -> Display configuration)
Comment 1 Alex Deucher 2016-04-14 17:07:31 UTC 
Please attach your xorg log and dmesg output.  Does the whole system freeze or just X?
Comment 2 Nicola Mori 2016-04-15 07:48:08 UTC 
Created attachment 122958 [details]
dmesg
Comment 3 Nicola Mori 2016-04-15 07:48:28 UTC 
Created attachment 122959 [details]
Xorg.0.log
Comment 4 Nicola Mori 2016-04-15 08:22:23 UTC 
The freeze is only related to X, I guess. If, after triggering it, I'm quick enough to switch to a tty then the system is still responsive, I can log in and input commands to the shell (this is how I got the dmesg after the freeze). If instead I wait a bit after the freeze then the keyboard and the mouse become unresponsive, and pressing Ctrl+Alt+F2 has no effect. The system gets stuck with a black screen, the mouse cursor can still be moved around but clicks have no effect. The same happens when switching back to X from the tty after the "quick switch to tty" mentioned above.
Comment 5 Michel Dänzer 2016-04-15 08:42:59 UTC 
The X desktop size changes from 1280x800 to 3200x1080 around the time the GPU hangs. Can you also reproduce the problem by only changing the desktop size, without changing anything about the external monitor, e.g. using something like

xrandr --fb 3200x1080

?
Comment 6 Nicola Mori 2016-04-15 08:58:44 UTC 
Changing the desktop size screws the screen but the system is still responsive. I can go back to a fully working situation with

xrandr --fb 1280x800

I attach the relevant parts of dmesg and Xorg.0.log.
Comment 7 Nicola Mori 2016-04-15 08:59:09 UTC 
Created attachment 122961 [details]
dmesg on screen resize
Comment 8 Nicola Mori 2016-04-15 08:59:35 UTC 
Created attachment 122962 [details]
Xorg.0.log for screen resize
Comment 9 Alex Deucher 2016-04-15 14:58:05 UTC 
Does disabling dpm fix the issue?  remove radeon.dpm=1 from your kernel command line in grub.  dpm is disabled by default on r6xx due to stability issues.
Comment 10 Nicola Mori 2016-04-15 15:25:45 UTC 
Yes, disabling dpm the problem vanishes.
Comment 11 Martin Peres 2019-11-19 09:14:42 UTC 
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/drm/amd/issues/707.

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