Created attachment 86871 [details]
kernel log file edited for relevant lines with nouveau problems

Boot linux kernel mainline 3.12-rc3 in arch linux. Graphics hardware is:

01:00.0 VGA compatible controller: NVIDIA Corporation G86GLM [Quadro FX 360M]
(rev a1)

KDM greeter allows login to KDE.

Within a few seconds of logging in to KDE the DE freezes, and the mouse and all
controls are frozen. It is not possible to get to a text console and reboot is
necessary to unfreeze the system - using stable 3.11.2 kernel to continue
working.

Nouveau packages installed are: 

$ sudo pacman -Ss nouveau
extra/nouveau-dri 9.2.0-2 [installed]
    Mesa drivers for Nouveau
extra/xf86-video-nouveau 1.0.9-1 (xorg-drivers xorg) [installed]
    Open Source 2D acceleration driver for nVidia cards

Attaching log file segments relevant to the crash as follows:
kernel-sep30-crash.log
error.sep30-crash.log
Xorg.0.log.sep30.log