kern/103432: panic: nfssvc_nfsd(): debug.mpsafenet=1 && Giant

Robert Watson rwatson at
Tue Dec 25 06:30:05 PST 2007

The following reply was made to PR kern/103432; it has been noted by GNATS.

From: Robert Watson <rwatson at>
To: Daniel Rudy <dcrudy at>
Cc: freebsd-gnats-submit at, freebsd-bugs at
Subject: Re: kern/103432: panic: nfssvc_nfsd(): debug.mpsafenet=1 && Giant
Date: Tue, 25 Dec 2007 14:23:11 +0000 (GMT)

 On Wed, 20 Sep 2006, Daniel Rudy wrote:
 >> Number:         103432
 >> Category:       kern
 >> Synopsis:       panic: nfssvc_nfsd(): debug.mpsafenet=1 && Giant
 >> Confidential:   no
 >> Severity:       critical
 >> Priority:       high
 >> Responsible:    freebsd-bugs
 >> State:          open
 >> Quarter:
 >> Keywords:
 >> Date-Required:
 >> Class:          sw-bug
 >> Submitter-Id:   current-users
 >> Arrival-Date:   Wed Sep 20 15:40:17 GMT 2006
 >> Closed-Date:
 >> Last-Modified:
 >> Originator:     Daniel Rudy
 >> Release:        6.1-RELEASE-p7
 >> Organization:
 >> Environment:
 >> Description:
 > This computer is configured as a NFS server and it also has IPSEC enabled.  When a NFS client accesses this server, the server imediately panics with the following error "panic: nfssvc_nfsd(): debug.mpsafenet=1 && Giant" and reboots hanging the client.  On a release 6.0 machine, debug.mpsafe is forced to 0 because IPSEC requires Giant.
 >> How-To-Repeat:
 > On a 6.1 system, enable IPSEC and NFS then try to access the server remotely.
 >> Fix:
 > Can't.  The OID for debug.mpsafenet is readonly.
 It would be very helpful to have a stack trace on this one.
 There's a reasonable chance that this bug is gone in 7.x as we now have an 
 entirely MPSAFE IPSEC implementation, and the debug.mpssafenet compat code has 
 been entirely removed.  However, it would be very helpful to know.  You should 
 be able to compile and use a 7.x kernel with a 6.x userspace, which would give 
 you a lower-risk way to determine this.  Make sure to do a 7.x buildworld 
 before 7.x buildkernel, but only to a 7.x installkernel, not 7.x 
 Robert N M Watson
 Computer Laboratory
 University of Cambridge

More information about the freebsd-bugs mailing list