Re: kern/44652: 'gpt destroy' panics

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

The following reply was made to PR kern/44652; it has been noted by GNATS.

From: Christoph Egger <Christoph_Egger%gmx.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: Hauke Fath <hf%spg.tu-darmstadt.de@localhost>, 
kern-bug-people%netbsd.org@localhost, 
 gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/44652: 'gpt destroy' panics
Date: Tue, 01 Mar 2011 11:08:59 +0100

 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