kern/64206: panic: lockmgr: locking against myself (kern_lock.c:370)

[Pawel Jakub Dawidek]

The following reply was made to PR kern/64206; it has been noted by GNATS.

From: Pawel Jakub Dawidek <pjd at FreeBSD.org>
To: Nik Clayton <nik at crf-consulting.co.uk>
Cc: FreeBSD-gnats-submit at FreeBSD.org
Subject: Re: kern/64206: panic: lockmgr: locking against myself (kern_lock.c:370)
Date: Tue, 16 Mar 2004 19:21:45 +0100

 --3MMMIZFJzhAsRj/+
 Content-Type: text/plain; charset=iso-8859-2
 Content-Disposition: inline
 Content-Transfer-Encoding: quoted-printable
 
 On Sat, Mar 13, 2004 at 10:39:53AM +0000, Nik Clayton wrote:
 +> >Description:
 +>=20
 +> After a clean boot, with background_fsck=3D"NO" in /etc/rc.conf (so the =
 disks=20
 +> had been fsck'd at startup), on a filesystem with softupdates enabled, I=
 =20
 +> could reliably reproduce a panic by doing something disk intensive, like
 +>=20
 +>     cd /usr/ports/multimedia/kdemultimedia3
 +>     make clean extract
 +>=20
 +> The panic would happen within a few seconds of the extraction starting.
 +>=20
 +> This was completely reproducible:
 +>=20
 +>     reboot
 +>     disks get fscked
 +>     login
 +>     'make clean extract'
 +>     panic
 +>=20
 +> and I did so several times for testing.
 +>=20
 +> A Google groups search for "kern_lock.c panic 370" shows numerous reports
 +> of this over the past year or so.  Most of them have linked this to=20
 +> background fsck.
 +>=20
 +> Since I had had background fsck enabled previously, I'll theorise wildly,
 +> and suggest that the problem is an interaction between the softupdates c=
 ode
 +> and snapshot code (since the previous, incomplete, background fscks will
 +> have left snapshots behind when the system panic'd before they completed=
 ).
 
 Thanks for reporting this! I've exactly same problem, but I was sure this
 is HW issue:)
 
 In my configuration I've only one partition, softupdates are off,
 so I don't know why snapshot is created (as it looks from your debug).
 
 --=20
 Pawel Jakub Dawidek                       http://www.FreeBSD.org
 pjd at FreeBSD.org                           http://garage.freebsd.pl
 FreeBSD committer                         Am I Evil? Yes, I Am!
 
 --3MMMIZFJzhAsRj/+
 Content-Type: application/pgp-signature
 Content-Disposition: inline
 
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.2.4 (FreeBSD)
 
 iD8DBQFAV0W5ForvXbEpPzQRAvKCAJ9oajjagXLC/R/7CzFHg8xN6ehMhgCfWseG
 UuR5M2tHLQojBOPUYEGx++c=
 =kEnz
 -----END PGP SIGNATURE-----
 
 --3MMMIZFJzhAsRj/+--