https://bugs.freedesktop.org/show_bug.cgi?id=110250

Bug ID: 110250 Summary: [Regression linux 5.1-rc1] Displayport 1.2 tty second monitor corruption Product: DRI Version: unspecified Hardware: x86-64 (AMD64) OS: Linux (All) Status: NEW Severity: normal Priority: medium Component: DRM/AMDgpu Assignee: dri-devel@lists.freedesktop.org Reporter: freedesktop@sibrenvasse.nl

Created attachment 143781 --> https://bugs.freedesktop.org/attachment.cgi?id=143781&action=edit Bisect log & result

I have two monitors daisy chained via Displayport 1.2.

GPU: Radeon RX 570 4GB amdgpu.dc=1 (issue does not occur when disabled)

After upgrading to Linux 5.1-rc1 when switching to a tty the second monitor (that's connected to the first) displays a corrupted version of the first monitor. Previously this would display a stretched version of monitor 1 (because of a different aspect ratio).

There is no output in dmesg when switching to a tty.

I have bisected the issue between tags v5.0 and v5.1-rc1. The result was bc7f670ee04cd619f8c4627c37d77b3618bc5edd as the first bad commit. Bisect log attached.

commit 8a48b44cd00f10e83f573b9028d11bd90a36de26 GOOD

commit bc7f670ee04cd619f8c4627c37d77b3618bc5edd BAD After switching from graphical environment to a tty, the second monitor will keep displaying the last frame of the graphical environment.

commit b2e85302494a6b7d3a3006c8d80a729377600628 BAD Screen display is corrupted.