Subject: Re: kern/35042: panic in vmem system (missing splfoo?)
To: None <kern-bug-people@netbsd.org, gnats-admin@netbsd.org,>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: netbsd-bugs
Date: 11/12/2006 19:25:02
The following reply was made to PR kern/35042; it has been noted by GNATS.

From: Manuel Bouyer <bouyer@antioche.eu.org>
To: gnats-bugs@NetBSD.org
Cc: kern-bug-people@NetBSD.org, gnats-admin@NetBSD.org,
	netbsd-bugs@NetBSD.org
Subject: Re: kern/35042: panic in vmem system (missing splfoo?)
Date: Sun, 12 Nov 2006 20:23:56 +0100

 On Sun, Nov 12, 2006 at 07:15:05PM +0000, Jason Thorpe wrote:
 > The following reply was made to PR kern/35042; it has been noted by GNATS.
 > 
 > From: Jason Thorpe <thorpej@shagadelic.org>
 > To: gnats-bugs@NetBSD.org
 > Cc: kern-bug-people@netbsd.org, gnats-admin@netbsd.org,
 > 	netbsd-bugs@netbsd.org
 > Subject: Re: kern/35042: panic in vmem system (missing splfoo?) 
 > Date: Sun, 12 Nov 2006 11:13:27 -0800
 > 
 >  On Nov 12, 2006, at 10:40 AM, Manuel.Bouyer@lip6.fr wrote:
 >  
 >  >> 	My Xen3 dom0 paniced twice today; each time in vmem(9). Looking at
 >  > 	backtrace I suspect a missing splfoo() somewhere: we get an interrupt
 >  > 	which ends up calling vmem_alloc() while we are in vmem_free().
 >  > 	Another Xen3 user reported a similar panic on port-xen:
 >  > 	http://mail-index.netbsd.org/port-xen/2006/11/08/0004.html
 >  
 >  I didn't think vmem was allowed in interrupt contexts...
 
 Then we have a problem; it can't be used for xen_shm
 Before vmem is used a extent_create(), which was fine for use in
 interrupt context.
 
 -- 
 Manuel Bouyer <bouyer@antioche.eu.org>
      NetBSD: 26 ans d'experience feront toujours la difference
 --