Re: kern/44652: 'gpt destroy' panics

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

On 03/01/11 11:00, Hauke Fath wrote:
> The following reply was made to PR kern/44652; it has been noted by GNATS.
>
> From: Hauke Fath<hf%spg.tu-darmstadt.de@localhost>
> To: gnats-bugs%NetBSD.org@localhost
> Cc: kern-bug-people%NetBSD.org@localhost, gnats-admin%NetBSD.org@localhost
> Subject: Re: kern/44652: 'gpt destroy' panics
> Date: Tue, 1 Mar 2011 10:58:40 +0100
>
>   At 17:15 Uhr +0000 28.02.2011, Hauke Fath wrote:
>   >  'gpt destroy raid0' when raid0 is on dk1 which has just been
>   >  'dkctl delwedge'd panics the machine.
>   >
>   >  For details, see the lovely picture (900 KByte) at
>   >  <http://la.causeuse.org/hauke/NetBSD/gpt-issues/gpt_destroy_panic.jpg>
>
>   And another one...
>
>   I deconstructed wedges and gpts of the above installation in the right
>   sequence, dd(1)ed the beginning of the disk, and ten seconds or so later
>   was hit with
>   <http://la.causeuse.org/hauke/NetBSD/gpt-issues/gpt_destroy_raid_panic.jpg>.
>
>         hauke

The same assembler instruction in both cases. When you do
'show register' in ddb (after the crash) and you see a line

  rax         0

then the crash is caused by a NULL pointer dereference.

When you built your kernel with makeoptions DEBUG="-g"
then you have a netbsd.gdb file and you can do:

gdb netbsd.gdb
(gdb) list *(dkstrategy+0x1a)

Christoph