Kernel panic with CAM on current (fatal trap 12)

[Kenneth D. Merry]

On Wed, Aug 27, 2003 at 00:49:56 +0200, Martin wrote:
> 
> Hi,
> 
> I compiled world and kernel tonight (Aug 26th) on my Thinkpad 
> R40 with a CD/RW drive. I tried my old settings with cam 
> enabled so I can use cdrecord.
> 
> During boot I got a kernel panic about 10 seconds after the
> kernel detected the CD/RW drive. Here some info:
> 
> Fatal trap 12: page fault while in kernel mode
> fault virtual address = 0x0
> fault code = supervisor write, page not present
> [...IP/SP reg values changing...]
> code segment = base 0x0, limit 0xfffff, type 0x1b
>              = DPL 0, pres 1, def32 1, gran 1
> processor eflags = interrupt enabled, resume, IOPL = 0
> current process = 20 (swi3:cambio)
> trap number = 12
> 
> In verbose mode it also showed some "non-retryable
> errors" while accessing ata0 and sbp0, before the
> kernel stops with the panic.
> 
> I could start the latest kernel after removing
> sbp, umass, cam-stuff and atapicam and recompiling
> it. The last kernel without these effects was compiled
> on Aug 18th.
> 
> I hope it helps, if not, I can write down more 
> information for you.

There are known problems with atapicam.

Try enabling DDB in your kernel config, and get a stack trace.  If you're
panicing in free_hcb(), disable atapicam and try again.

Ken
-- 
Kenneth Merry
ken at kdm.org