My Dell D620 is also exhibiting this or a closely related issue. Coming back from suspend I occasionally enter the gdm restart loop which terminates (with failure) after a couple of iterations.
An interesting thing is that this problem occurs more frequently after the machine has been suspended for a longer period of time. If I suspend the machine and immediately wake it back up, I almost never see this bug. However I see it about 20% of the time after the machine has been suspended for a few hours. I'm going to try enabling SAVE_VIDEO_PCI_STATE=true in /etc/default /acpi-support and see if that makes a difference. Here are the relevant details: lspci: 00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS/940GML Express Integrated Graphics Controller (rev 03) Xorg: Error in I830WaitLpRing(), now is -354572395, start is -354574396 pgetbl_ctl: 0x3ffc0001 pgetbl_err: 0x0 ipeir: 0 iphdr: 0 LP ring tail: f8 head: 0 len: 1f001 start 0 eir: 0 esr: 1 emr: ffff instdone: ffc1 instpm: 0 memmode: 10f instps: 2014c0 hwstam: fffe ier: 2 imr: 0 iir: 20 space: 130816 wanted 131064 (II) I810(0): [drm] removed 1 reserved context for kernel (II) I810(0): [drm] unmapping 8192 bytes of SAREA 0xf8b8d000 at 0xb7a87000 Fatal server error: lockup <...snip...> FatalError re-entered, aborting lockup -David Carr -- i810 Xv crashes after suspend -> infinite resprawn https://launchpad.net/bugs/28326 -- kubuntu-bugs mailing list kubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/kubuntu-bugs