kern/49088: New DRMKMS kernel panics on my amd64 + radeon IGP (RS780) machine

[mk%kilbi.de@localhost]

>Number:         49088
>Category:       kern
>Synopsis:       New DRMKMS kernel panics on my amd64 + radeon IGP (RS780) 
>machine
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Aug 07 16:30:01 +0000 2014
>Originator:     Markus W Kilbinger
>Release:        NetBSD 6.99.49
>Organization:
        
>Environment:
        
        
System: NetBSD qie 6.99.49 NetBSD 6.99.49 (Q) #0: Tue Aug 5 13:05:52 MEST 2014 
root@q:/usr/u/NetBSD/HEAD/src/sys/arch/amd64/compile/Q amd64
Architecture: x86_64
Machine: amd64
>Description:
        After recent DRMKMS changes I compiled an actual preconfigrued
        DRMKMS kernel for my amd64 + radeon IGP (RS780) machine (asus
        m3a78-t).

        Booting this kernel ends up in a panic quite at the end of the
        normal dmesg-output with 'Unable to locate a BIOS ROM':

          http://nice.afraid.org/DRMKMS-uSJg+K1/DRMKMS-panic1.jpeg
          http://nice.afraid.org/DRMKMS-uSJg+K1/DRMKMS-panic2.jpeg

        My normal and working radeondrm - kernel's dmesg for
        reference:

          http://nice.afraid.org/DRMKMS-uSJg+K1/dmesg.txt

>How-To-Repeat:
        Compile an amd64 DRMKMS kernel (from .../amd64/conf/DRMKMS
        config), boot it on a asus m3a78-t machine and see how it
        fails / panics.

>Fix:
        Unknown.

>Unformatted: