Created attachment 103841 [details]
full dmesg output with the 2 crashes included (Magic SYSRQ + k), reiserfs is
/boot (storing the info there)

summary: 1st crash happened within fluxbox + chromium (html5 video) on youtube,
movie trailers


right after Magic SYSRQ + k, xdm (slim) came up again

erroneously got into Xfce4 + compiz-fusion,


then exited and got into fluxbox + chromium again

here the 

2nd crash happened during attempt to open up/loading of bugs.freedesktop.org
(via chromium)


now posting this information from fluxbox + firefox 31 (compiled on this
system) still on the running system (no system reboot !) - so gpu state got
more stable than previous drm-next-3.17-rebased-on-fixes


dmesg output seems to suggest that it's still related & an issue introduced
with the recent GPUVM changes


hope this information is valuable and helps in tracking down where the problem
lies