From owner-freebsd-current@FreeBSD.ORG Fri Jun 15 18:25:22 2007 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id C152316A479 for ; Fri, 15 Jun 2007 18:25:22 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.freebsd.org (Postfix) with ESMTP id 93CCE13C489 for ; Fri, 15 Jun 2007 18:25:22 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 816871A4D8F; Fri, 15 Jun 2007 11:24:49 -0700 (PDT) Received: from rot13.obsecurity.org (rot13.obsecurity.org [192.168.1.5]) by obsecurity.dyndns.org (Postfix) with ESMTP id AC00C513DD; Fri, 15 Jun 2007 14:25:21 -0400 (EDT) Received: by rot13.obsecurity.org (Postfix, from userid 1001) id A5886BE8F; Fri, 15 Jun 2007 14:25:21 -0400 (EDT) Date: Fri, 15 Jun 2007 14:25:21 -0400 From: Kris Kennaway To: Benjamin Close Message-ID: <20070615182521.GB9619@rot13.obsecurity.org> References: <4672945C.3060304@clearchain.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="6c2NcOVqGQ03X4Wi" Content-Disposition: inline In-Reply-To: <4672945C.3060304@clearchain.com> User-Agent: Mutt/1.4.2.3i Cc: freebsd-current@freebsd.org Subject: Re: Swapfile on ZFS & Deadlock X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Jun 2007 18:25:22 -0000 --6c2NcOVqGQ03X4Wi Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jun 15, 2007 at 11:00:04PM +0930, Benjamin Close wrote: > Hi All, > Whilst running out of memory compiling Xorg (scanPCI is a killer) I=20 > discovered a quick way to deadlock the system: >=20 > dd if=3D/dev/zero of=3Dsomefileonzfs bs=3Dsomething count=3Dsomething > mdconfig -a -f something > swapon /dev/md0 >=20 > Then do something that needs swap.. instant deadlock. The system is=20 > still responsive but all disk access become hung. >=20 > Known issue? If so is there a way we can warn users/prevent users from=20 > doing it? Enable DEBUG_VFS_LOCKS and DEBUG_LOCKS, then break to DDB when the deadlock occurs and do 'show lockedvnods'. Kris --6c2NcOVqGQ03X4Wi Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.3 (FreeBSD) iD8DBQFGctmRWry0BWjoQKURAsidAJwLaPKf9Fsjcb3/bL1xaBdgmWKfgACeO7vP vXSNYoA0poAnJcjHGb3W8+I= =ZarY -----END PGP SIGNATURE----- --6c2NcOVqGQ03X4Wi--