Ubuntu
linux package

  1. Bug #1882442
  2. Comment #9

Comment 9 for bug 1882442

Revision history for this message
David W Craig (davidwcraigx) wrote :

I found a similar Fedora bug report, it is a kernel issue, and there is a workaround. See: https://bugzilla.redhat.com/show_bug.cgi?id=1594488

Need to add 'amdgpu.dc=0' to the kernel command line in grub.cfg:

GRUB_CMDLINE_LINUX="amdgpu.dc=0"
then run grub-update

reboot

after booting to a version 5 kernel, video on both monitors works, and a check of the proc cmdline shows:
$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-5.4.0-40-generic root=UUID=95b8de7f-9de3-4cea-b947-e135a738948c ro amdgpu.dc=0