Subject: Re: port-i386/10187: consistent panic: lockmgr: no context
To: None <thorpej@zembu.com>
From: Simon Burge <simonb@netbsd.org>
List: tech-kern
Date: 05/24/2000 14:00:28
Jason R Thorpe wrote:

> On Tue, May 23, 2000 at 10:59:44PM -0400, John Hawkinson wrote:
> 
>  > >Category:       port-i386
> 
> This is not i386-specific.
> 
>  > >Fix:
>  > 	I dunno. This panic happens if curproc is NULL upon entry into
>  > lockmgr(), but I don't know what causes curproc to go NULL, other than
>  > cpu_switch(), and I'm presuming that's not what is going on here.
> 
> curproc is NULL when the system is idle.  If you then get an interrupt
> which leads to a panic, curproc is obviously still NULL and the problem
> occurs.
> 
> The alternative, of course, is for lockmgr() to simply dereference NULL
> when it attempts to store the pid of the locking process in the lock
> structure.

Dumb question time - do we need that lock just to sync the disks and
create a crash dump?  I dunno if it's possible, but say the system gets
wedged in the idle loop for some reason - not being able to get a dump
could be painful...

> Which do you prefer?  Random kernel fault or meaningful panic? :-)

Simon.