Hm. That does sound nasty. I think you've probably already reported the items of interest - I'll pass them on to the dev team and see if they have anything to say about it. You should be able to remove the i915 update by doing the following:
apt-get remove i915-4.3.3-4.2.0-dkms
and then rebooting. Does that fix the problem? If so it's a bug in the backported i915 driver,
in which case we'd be interested in the output of
lspci -kvnn
Hello,
I have an HP nc6320 Laptop that is running 32bit Ubuntu 15.10.
I thought I'd try the Intel graphics installer 1.4.0 as there are some minor glitches with window movement and corner transparency on my machine.
The drivers installed without error as far as I could see, but on reboot, the usual Ubuntu login screen did not appear.
What happens now is the mouse pointer appears correctly, and can move around, and the ubuntu "drums" sound, but in the top 1cm (ish) , there is a ubuntu purple stripe, and the rest of the screen is blank.
In this purple stripe, there are a few white pixels, that start off in the top left of the stripe, and as I move the mouse pointer around, more white pixels appear.
If I type my password in as normal, my Ubuntu desktop appears as normal (sadly the screen corruption hasn't been fixed by this installation).
While this is workable, if I ever need to log in to my machine as another user, I'm in trouble as I can't see the login screen to select other users or window managers.
There are warnings in the syslog file, but I don't know if this is important:
WARNING: CPU: 0 PID: 113 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/i915/intel_display.c:1391 assert_planes_disabled+0x100/0x140 [i915]()
WARNING: CPU: 0 PID: 79 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/drm_atomic.c:493 drm_atomic_check_only+0x4bf/0x5a0 [drm]()
WARNING: CPU: 0 PID: 79 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/i915/intel_fbdev.c:402 intel_fb_initial_config+0x2dc/0x5f0 [i915]()
WARNING: CPU: 0 PID: 4 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/i915/intel_fbdev.c:402 intel_fb_initial_config+0x2dc/0x5f0 [i915]()
WARNING: CPU: 0 PID: 4 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/i915/intel_display.c:11673 intel_plane_atomic_calc_changes+0x51c/0x690 [i915]()
CPU: 0 PID: 4 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/drm_atomic_helper.c:676 drm_atomic_helper_update_legacy_modeset_state+0x26a/0x280 [drm_kms_helper]()
WARNING: CPU: 0 PID: 4 at /var/lib/dkms/i915-4.3.3-4.2.0/2/build/drivers/gpu/drm/i915/intel_display.c:1391 assert_planes_disabled+0x100/0x140 [i915]()
gpu-manager[1196]: update-alternatives: warning: alternative /usr/lib/i386-linux-gnu/mesa/ld.so.conf (part of link group i386-linux-gnu_gl_conf) doesn't exist; removing from list of alternatives
Is there anything I can check to find out why the login screen isn't displaying properly?
Thanks