TearFree is lost after switching output monitors
Submitted by Martin Kjær Jørgensen @mkj
Assigned to Chris Wilson @ickle
Description
I'm running latest Debian Stretch on a ThinkPad X1 Carbon 20A7, sometimes attached to a dock.
When detaching or attaching my dock with a DP monitor attached, my video output gets teared. I saw this in the attached Xorg.0.log:
[ 807.026] (II) intel(0): switch to mode 2560x1440@60.0 on DP2-2 using pipe 1, position (0, 0), rotation normal, reflection none
[ 1123.133] (EE) intel(0): Failed to prepare CRTC for page flipping, disabling TearFree
[ 1123.690] (II) intel(0): switch to mode 2560x1440@60.0 on eDP1 using pipe 0, position (0, 0), rotation normal, reflection none
[ 1123.986] (EE) intel(0): Failed to prepare CRTC for page flipping, disabling TearFree
[ 1123.991] (II) intel(0): Disabled output DP2-1
[ 1123.991] (II) intel(0): Disabled output DP2-2
[ 1123.991] (II) intel(0): Disabled output DP2-3
[ 11204.479] (II) intel(0): Enabled output DP2-1
[ 11204.479] (II) intel(0): Enabled output DP2-2
[ 11204.479] (II) intel(0): Enabled output DP2-3
Any ideas?