Created attachment 186721 [details] dmesg output This originates from another bug 104001. 4.2 kernel spews many kernel warnings on HP EliteBook 940 G1 laptop with Haswell chip. At booting: [ 5.205358] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in has_drrs (expected 1, found 0) [ 5.205361] ------------[ cut here ]------------ [ 5.205387] WARNING: CPU: 3 PID: 76 at drivers/gpu/drm/i915/intel_display.c:12691 intel_modeset_check_state+0x5a4/0x870 [i915]() [ 5.205388] pipe state doesn't match! At plugging DP on dock (MST): [ 33.096865] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in has_drrs (expected 1, found 0) [ 33.096876] ------------[ cut here ]------------ [ 33.096916] WARNING: CPU: 3 PID: 988 at drivers/gpu/drm/i915/intel_display.c:12691 intel_modeset_check_state+0x5a4/0x870 [i915]() [ 33.096919] pipe state doesn't match! .... [ 33.230467] WARNING: CPU: 3 PID: 988 at drivers/gpu/drm/i915/intel_display.c:6330 intel_modeset_check_state+0x112/0x870 [i915]() [ 33.230472] attached crtc is active, but connector isn't At unplugging DP: [ 218.764695] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in has_drrs (expected 1, found 0) [ 218.764706] ------------[ cut here ]------------ [ 218.764739] WARNING: CPU: 3 PID: 988 at drivers/gpu/drm/i915/intel_display.c:12691 intel_modeset_check_state+0x5a4/0x870 [i915]() [ 218.764741] pipe state doesn't match! Note that this is the patched kernel based on vanilla 4.2 and pulling drm-intel-next-fixes (commit 4e3d1e26c2b2c40ebff69f2825fa862bfcf082d1).
Presumed fixed upstream, closing. If the problem persists with latest kernels, please file a bug at the freedesktop.org bugzilla [1], referencing this bug. Thank you. [1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI&component=DRM/Intel