Ubuntu
linux package

  1. Disco (19.04)
  2. Bug #1826691
  3. Comment #9

Comment 9 for bug 1826691

Revision history for this message
You-Sheng Yang (vicamo) wrote :

This is a small C program doing exactly the same thing as fwupd does to trigger this issue. Usage: `sudo ./read-dpcd /dev/drm_dp_aux<N>`.

To find out what <N> is, replace ExecStart property in `/lib/systemd/system/fwupd.service` from `/usr/lib/fwupd/fwupd` to `/usr/bin/strace -D -tt -y -f -o /var/lib/fwupd/strace.log /usr/lib/fwupd/fwupd`. Find the last open /dev/drm_dp_aux*.

This was first reported on a premature hardware platform. It was fixed automatically with a second DVT release and without additional effort being done in the kernel space.