From owner-freebsd-stable@FreeBSD.ORG Sat Sep 8 18:17:38 2007 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8AD5C16A41B; Sat, 8 Sep 2007 18:17:38 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from relay02.kiev.sovam.com (relay02.kiev.sovam.com [62.64.120.197]) by mx1.freebsd.org (Postfix) with ESMTP id 2BF8113C46A; Sat, 8 Sep 2007 18:17:38 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from [212.82.216.226] (helo=deviant.kiev.zoral.com.ua) by relay02.kiev.sovam.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.67) (envelope-from ) id 1IU4s4-000448-4X; Sat, 08 Sep 2007 21:17:36 +0300 Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.1/8.14.1) with ESMTP id l88IHQps053682; Sat, 8 Sep 2007 21:17:26 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.1/8.14.1/Submit) id l88IHQp3053681; Sat, 8 Sep 2007 21:17:26 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Sat, 8 Sep 2007 21:17:26 +0300 From: Kostik Belousov To: Maxim Sobolev Message-ID: <20070908181726.GR53667@deviant.kiev.zoral.com.ua> References: <46E19D4E.1060009@FreeBSD.org> <20070908040233.GP53667@deviant.kiev.zoral.com.ua> <46E25620.6050906@FreeBSD.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Pa4xkLBhPDIhDLv1" Content-Disposition: inline In-Reply-To: <46E25620.6050906@FreeBSD.org> User-Agent: Mutt/1.4.2.3i X-Scanner-Signature: a96565856d7d777f03ae631b61e05b17 X-DrWeb-checked: yes X-SpamTest-Envelope-From: kostikbel@gmail.com X-SpamTest-Group-ID: 00000000 X-SpamTest-Info: Profiles 1448 [September 7 2007] X-SpamTest-Info: helo_type=3 X-SpamTest-Info: {received from trusted relay: not dialup} X-SpamTest-Method: none X-SpamTest-Method: Local Lists X-SpamTest-Rate: 0 X-SpamTest-Status: Not detected X-SpamTest-Status-Extended: not_detected X-SpamTest-Version: SMTP-Filter Version 3.0.0 [0255], KAS30/Release Cc: stable@freebsd.org Subject: Re: kqueue LOR X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 08 Sep 2007 18:17:38 -0000 --Pa4xkLBhPDIhDLv1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Sep 08, 2007 at 12:58:24AM -0700, Maxim Sobolev wrote: > Kostik Belousov wrote: > >On Fri, Sep 07, 2007 at 11:49:50AM -0700, Maxim Sobolev wrote: > >>Hi, > >> > >>On my 6.2 system I am seeing LOR discussed almost 1 year ago here: > >> > >>http://lists.freebsd.org/pipermail/freebsd-stable/2006-November/031048.= html > >>http://lists.freebsd.org/pipermail/freebsd-stable/2006-December/031197.= html > >> > >>lock order reversal: > >> 1st 0xc52cb500 kqueue (kqueue) @ kern/kern_event.c:1547 > >> 2nd 0xc4e4d80c struct mount mtx (struct mount mtx) @=20 > >>ufs/ufs/ufs_vnops.c:138 > >> > >>Do you have any plans to commit the suggested fix? > >I suspect that the LOR is bogus. I was never able to get the information > >where the reverse lock order happen. What I asked of the most reporters = is > >to apply sys/kern/subr_witness.c rev. 1.222 to RELENG_6 and provide me > >with the LOR report, if any. >=20 > What do you mean "bogus"? It happens reliably on my system. Bogus means that reported LOR, most likely, do not cause actual deadlock. >=20 > >Note that doing that on RELENG_6_2 makes no sense, most likely you will > >get LORs with cdev mutex, fixed in RELENG_6. >=20 > I don't quite understand that. RELENG_6_2 had known LOR that already was fixed in RELENG_6, between cdev mutex and and sleep mtxpool, namely LOR #197. After user have applyed rev. 1.222 of subr_witness, I usuallygot the reports of that LOR, if any, but not the LOR I needed. --Pa4xkLBhPDIhDLv1 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFG4uc1C3+MBN1Mb4gRAm1lAKCYjRK37Y0e4T8bTcc4IgTcWbihMwCdFvx/ OOdhjqemRPR1JIiH5ls32VQ= =esTX -----END PGP SIGNATURE----- --Pa4xkLBhPDIhDLv1--