Hi! Just an FYI I am planning on taking a look at this very soon On Mon, 2017-03-27 at 18:02 +0200, Takashi Iwai wrote: > Hi, > > the upstream fix a16b7658f4e0d4aec9bc3e75a5f0cc3f7a3a0422 > drm/i915: Call intel_dp_mst_resume() before resuming displays > > seems to trigger a kernel panic when some modeset change happens > after > S3 resume. The details are found in openSUSE bugzilla, > https://bugzilla.suse.com/show_bug.cgi?id=1029634 > > In short, the following procedure causes a kernel panic (supposedly) > almost 100% on Dell Latitude with Skylake with MST DP on dock: > > - Boot with a docking station, DP-1 connected. > - Login on X > - xrandr --output eDP-1 --primary --auto --output DP-1-1 --auto -- > left-of eDP-1 > ==> This changes the mode. > - Suspend ("systemctl suspend" in my case), and close the lid. > - Remove from the dock (keep the lid closed). > - Open the lid, which resumes automatically. It works. > - Suspend again. > - Connect to the dock again (keep the lid closed). > - Open the lid, which resumes automatically. It's still OK. > - xrandr --output eDP-1 --primary --auto --output DP-1-1 --auto -- > left-of eDP-1 > ==> Now the kernel feezes. > > Reverting the commit mentioned above fixes the problem. > > The problem is present in all versions I tested. The reported kernel > in the Bugzilla is 4.4.x-based one, but the issue is seen in 4.11- > rc3, > too. Note that the S3 resume itself works in 4.11-rc3; the kernel > panic happens when invoking xrandr manually after that. > > Unfortunately, I couldn't get a kernel panic message, so far. kdump > didn't work well in this case by some reason. There are some > screenshots taken by the original reporter (could switch VT > beforehand), but I don't know whether it helps. > > If you have any hints for further debugging, it'd be highly > appreciated. > > > thanks, > > Takashi _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
