misc/185182: xorg of 10-RC2 has blank screen on APU-3400 system

[Jin Guojun]

>Number:         185182
>Category:       misc
>Synopsis:       xorg of 10-RC2 has blank screen on APU-3400 system
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Dec 25 19:10:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Jin Guojun
>Release:        10.0-RC2
>Organization:
>Environment:
FreeBSD FB-10 10.0-RC2 FreeBSD 10.0-RC2 #0 r259404: Sun Dec 15 08:18:20 UTC 2013
     root at snap.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64

ASUS FM1-A75 motherboard + ADM A3400 APU
>Description:
When running "X -configure", it crashed with following error:

X.Org X Server 1.7.7
Release Date: 2010-05-04
X Protocol Version 11, Revision 0
Build Operating System: FreeBSD 10.0-BETA1 amd64
Current Operating System: FreeBSD FB-10 10.0-RC2 FreeBSD 10.0-RC2 #0 r259404: Su
n Dec 15 08:18:20 UTC 2013     root at snap.freebsd.org:/usr/obj/usr/src/sys/GENERI
C amd64
Build Date: 05 December 2013  08:08:22PM
........

(II) GPU only supported with KMS, using vesa instead.
Segmentation fault at address 0x0

Fatal server error:
Caught signal 11 (Segmentation fault). Server aborting

----------------

After switch device from Radeon to Vesa as suggested (this works for 8.3 and 8.4 releases on the same system), X will start with a blank screen.
Altr-Ctrl-F1 can bring system back to the text console, and it means that system is still alive.

Since Xorg works on FreeBSD 8.3-R and 8.4-Release, so this is a xorg problem in 10-R.
>How-To-Repeat:
Not sure if this is for all systems with FM1 socketed APU.
Install FreeBSD 10-RC2 on ASUS FM1-A75 motherboard with A3400 APU.
Run "X -configure", modify device Driver from radeon to vesa in Section "Device", and then start X with this xorg.conf.new. You will see a blank screen.
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: