Description of problem:

The nouveau driver in the rawhide kernel has a bug and is in the top 10 of 
kernel oopses:

http://www.kerneloops.org/searchweek.php?search=do_sys_open

This is caused by nouveau returning "1" somewhere for an error rather than "-
1". The effect of this bug is that the kernel doesn't recognize this as an 
error condition and considers this a real pointer.. which it then follows in 
do_sys_open, with an oops as result.

Most likely candidate is:

+       if (ret) {
+               DRM_ERROR("Unable to initialize the mmio mapping (%d). "
+                         "Please report your setup to " DRIVER_EMAIL "\n",
+                         ret);
+               return 1;
+       }