Kernel panic when external monitors go blank

Submitted by Ainola

Assigned to Default DRI bug account

Link to original bug (#107863)

Description

Created attachment 141478
kernel panic

This is a follow-up from bug https://bugs.freedesktop.org/show_bug.cgi?id=105018. If I leave my laptop in its dock (one HDMI and one DisplayPort) it has a high chance of kernel panicking when DPMS turns the displays off. This affects my Dell Precision 7720 with a Radeon Pro WX 7100 on Archlinux, kernel 4.18.5. My boot parameters include amdgpu.dc=1 (a redundant option nowadays, I know, I forgot to remove this option). Suspend/resume work are fine, this happens only immediately after idle blanking. As far as I can tell this does not occur when using only the laptop screen but I could be wrong as I spend the majority of my time on the dock.


I've attached a kernel log. For now I work around the issue by disabling dpms entirely.

Thank you!

Attachment 141478, "kernel panic":
kernel.log