Intel KMS Cannot runin framebuffer mode

[tsuraan]

>> My guess is that my xorg.conf somehow conflicts with KMS, so, since X
>> is now supposed to work without a config file, I'd give that a try.
>> The xorg.conf that I'm trying to use is attached (if I'm lucky...).

As it turns out, the xorg.conf isn't relevant.  I removed the fbdev
and vesa drivers from my machine, and now without any config file I
get the same backtrace.  It looks like the actual segv is in libdrm;
my version of that library is 2.4.11, which is the latest that gentoo
offers in their stable tree.  Do I need a newer (development?) version
of libdrm to use modesetting?