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: dfr at freebsd.org
Cc: Manuel Tobias Schiller <mala at hinterbergen.de>,
        FreeBSD-gnats-submit at freebsd.org
Subject: Re: sparc64/142102: FreeBSD 8.0 kernel panics on sparc64 when accessing NFS
Date: Wed, 30 Dec 2009 17:36:27 +0100

 On Wed, Dec 30, 2009 at 01:25:55AM +0100, Manuel Tobias Schiller wrote:
 > On Tue, 29 Dec 2009 19:53:58 +0100
 > Marius Strobl <marius at alchemy.franken.de> wrote:
 > > 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
 > 
 > I managed to compile and test a kernel with your updated patch, and things
 > seem to work. I'll try to stress-test it over the night by copying a few
 > tens of gigabytes over and report back with the results.
 
 Doug,
 
 could you please review the following patch? The problem
 apparently is that nfsm_srvmtofh_xx() assumes the 4-byte
 alignment required by XDR so fha_extract_info() has to
 ensure that the mbuf data is aligned accordingly.
 http://people.freebsd.org/~marius/fha_extract_info_realign.diff
 
 Thanks,
 Marius