From owner-freebsd-current Tue Mar 26 17: 2:21 2002 Delivered-To: freebsd-current@freebsd.org Received: from obsecurity.dyndns.org (adsl-64-169-104-17.dsl.lsan03.pacbell.net [64.169.104.17]) by hub.freebsd.org (Postfix) with ESMTP id AFFBA37B405; Tue, 26 Mar 2002 17:02:16 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 1977E66D19; Tue, 26 Mar 2002 17:02:16 -0800 (PST) Date: Tue, 26 Mar 2002 17:02:15 -0800 From: Kris Kennaway To: Alfred Perlstein Cc: Kris Kennaway , current@FreeBSD.org Subject: Re: Lock order reversals in sys_pipe.c Message-ID: <20020326170215.A45743@xor.obsecurity.org> References: <20020324142632.A60767@xor.obsecurity.org> <20020326224307.GE93885@elvis.mu.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="cNdxnHkX5QqsyA0e" Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <20020326224307.GE93885@elvis.mu.org>; from alfred@FreeBSD.org on Tue, Mar 26, 2002 at 02:43:07PM -0800 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG --cNdxnHkX5QqsyA0e Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Mar 26, 2002 at 02:43:07PM -0800, Alfred Perlstein wrote: > * Kris Kennaway [020324 14:26] wrote: > > The bento cluster is now running with WITNESS enabled to try and track > > down some odd UMA lock corruption panics. Instead, it found the > > following lock order reversal in sys_pipe.c overnight: > >=20 > > Mar 24 07:31:44 gohan17 kernel: lock order reversal > > Mar 24 07:31:44 gohan17 kernel: 1st 0xcf51aa80 pipe mutex @= /local0/scratch/usr/src/sys/kern/sys_pipe.c:450 > > Mar 24 07:31:44 gohan17 kernel: 2nd 0xcf88dadc process lock= @ /local0/scratch/usr/src/sys/kern/kern_sig.c:2093 > > Mar 24 07:32:12 gohan10 kernel: lock order reversal > > Mar 24 07:32:12 gohan10 kernel: 1st 0xd9a29dc0 pipe mutex @= /local0/scratch/usr/src/sys/kern/sys_pipe.c:450 > > Mar 24 07:32:12 gohan10 kernel: 2nd 0xd961addc process lock= @ /local0/scratch/usr/src/sys/kern/kern_sig.c:2093 > > Mar 24 07:32:57 gohan12 kernel: lock order reversal > > Mar 24 07:32:57 gohan12 kernel: 1st 0xd9423080 pipe mutex @= /local0/scratch/usr/src/sys/kern/sys_pipe.c:450 > > Mar 24 07:32:57 gohan12 kernel: 2nd 0xdaa704dc process lock= @ /local0/scratch/usr/src/sys/kern/kern_sig.c:2093 > > Mar 24 09:02:29 gohan13 kernel: lock order reversal > > Mar 24 09:02:29 gohan13 kernel: 1st 0xd99d6500 pipe mutex @= /local0/scratch/usr/src/sys/kern/sys_pipe.c:450 > > Mar 24 09:02:29 gohan13 kernel: 2nd 0xd971cddc process lock= @ /local0/scratch/usr/src/sys/kern/kern_sig.c:2093 > >=20 > > Those source references are from a -current kernel from last night. >=20 > Are you %100 on that? How did you get this to happen? Yes. I wasn't doing anything special, unless you count building 5-10 packages simultaneously for a period of 24 hours counts as special ;-) I had to increase the witness limits in order to stop getting the following: witness_get: witness exhausted Well, I eventually got it anyway on all of the machines, but it didn't happen instantly like it did with the default values ;-) I haven't seen any more witness warnings, but it's probably only because it ran out of resources. I expect I'll see it again when I reboot the cluster. Kris --cNdxnHkX5QqsyA0e Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE8oRnzWry0BWjoQKURAqlgAJ9VtwZFyK39A/IvX3pA9x0k1KFzmACg9p7B OtoEebKmuAm0+pZbc9Cv8TE= =VpVh -----END PGP SIGNATURE----- --cNdxnHkX5QqsyA0e-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message