kern/153757: Kernel panic using openchrome Xorg driver on 9-CURRENT

[James Butler]

>Number:         153757
>Category:       kern
>Synopsis:       Kernel panic using openchrome Xorg driver on 9-CURRENT
>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:   Fri Jan 07 10:40:01 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     James Butler
>Release:        9-CURRENT
>Organization:
>Environment:
FreeBSD multivac.local 9.0-CURRENT FreeBSD 9.0-CURRENT #2: Fri Jan  7 22:06:43 NZDT 2011     james at multivac.local:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
Machine is a (crappy) VIA A8V-MX motherboard with K8M800 IGP. I built and installed CURRENT to try the newish via drm bits, but starting X with the openchrome driver results in the following panic:

lock "via_blit_lk" 0xffffff80006b4de8 already initialized

with the backtrace:

db:0:kdb.enter.panic>  bt
Tracing pid 2613 tid 100108 td 0xfffffe0002d59000
kdb_enter() at kdb_enter+0x3d
panic() at panic+0x180
lock_init() at lock_init+0x6a
via_init_dmablit() at via_init_dmablit+0xc3
via_map_init() at via_map_init+0x146
drm_ioctl() at drm_ioctl+0x2f2
devfs_ioctl_f() at devfs_ioctl_f+0x7a
kern_ioctl() at kern_ioctl+0xbe
ioctl() at ioctl+0xfd
syscallenter() at syscallenter+0x1aa
syscall() at syscall+0x4c
Xfast_syscall() at Xfast_syscall+0xe2
>How-To-Repeat:
On my K8M800-based machine:

Install the port x11-drivers/xf86-video-openchrome
Start Xorg
>Fix:
Two workarounds I know of:
* Downgrade to 8.x
* Use the vesa driver

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