sparc64/142102: FreeBSD 8.0 kernel panics on sparc64 when accessing NFS

[Marius Strobl]

The following reply was made to PR sparc64/142102; it has been noted by GNATS.

From: Marius Strobl <marius at alchemy.franken.de>
To: Manuel Tobias Schiller <mala at hinterbergen.de>
Cc: Mark Linimon <linimon at lonesome.com>, FreeBSD-gnats-submit at FreeBSD.org
Subject: Re: sparc64/142102: FreeBSD 8.0 kernel panics on sparc64 when accessing NFS
Date: Tue, 29 Dec 2009 19:53:58 +0100

 On Tue, Dec 29, 2009 at 04:34:11PM +0100, Manuel Tobias Schiller wrote:
 > On Tue, 29 Dec 2009 01:58:29 +0100
 > Marius Strobl <marius at alchemy.franken.de> wrote:
 > > I'm using a more or less current HEAD but the NFS code hasn't
 > > changed that much since 8.0, at least it doesn't contain any
 > > other alignment fixes I'm aware of.
 > > I think I got what the problem is but I still haven't managed
 > > to reproduce it so far. Could you please test whether the
 > > following patch makes a difference?
 > > http://people.freebsd.org/~marius/fha_extract_info_realign.diff
 > > 
 > > Marius
 > 
 > I applied the patch, compiled the kernel and rebooted. NFS read access
 > seems to work as before. When I try to write to the server, the server
 > locks up solid, i.e. I do not even get a kernel panic reported on the
 > serial console, so I can't give you a backtrace or anything. I had to
 > disconnect the cable from the wall outlet to the power supply to restart
 > it. It came up without problems, though.
 > 
 
 Oh, sorry, I had a bug in there, the svc code used a stale
 pointer to the mbuf with this. Could you please re-fetch
 and try again? I can't guarantee that this fixes the hang
 you experienced but at least in theory just re-aligning
 the data can't make the issue with the unaligned access
 any worse. Using the LOM or by breaking into the kernel
 by sending a break you should be able to power-cycle/
 reboot the machine without removing the power cord should
 it hang again though.
 What NFS client and with which mount options are you
 using to trigger is problem?
 
 Marius