From owner-freebsd-current@FreeBSD.ORG Sun Aug 7 00:24:06 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AD5371065672; Sun, 7 Aug 2011 00:24:06 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.zoral.com.ua (mx0.zoral.com.ua [91.193.166.200]) by mx1.freebsd.org (Postfix) with ESMTP id 272D78FC14; Sun, 7 Aug 2011 00:24:05 +0000 (UTC) Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id p770Nr3p088133 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 7 Aug 2011 03:23:53 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4) with ESMTP id p770Nq1Q063525; Sun, 7 Aug 2011 03:23:52 +0300 (EEST) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.4/8.14.4/Submit) id p770NqbR063524; Sun, 7 Aug 2011 03:23:52 +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: Sun, 7 Aug 2011 03:23:52 +0300 From: Kostik Belousov To: bf1783@gmail.com Message-ID: <20110807002351.GL17489@deviant.kiev.zoral.com.ua> References: <20110806144325.GE17489@deviant.kiev.zoral.com.ua> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="C2H3fAq9VP7LQDT/" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: clamav-milter 0.95.2 at skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-3.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00, DNS_FROM_OPENWHOIS autolearn=no version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua Cc: freebsd-current@freebsd.org, mm@freebsd.org Subject: Re: Recursive nullfs mounts and r224655 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: Sun, 07 Aug 2011 00:24:06 -0000 --C2H3fAq9VP7LQDT/ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Aug 06, 2011 at 08:11:32PM -0400, b. f. wrote: > On 8/6/11, Kostik Belousov wrote: > > On Sat, Aug 06, 2011 at 04:44:25AM -0400, b. f. wrote: > >> Recent changes to the kernel (sys/kern/vfs_mount.c, in r224655?) > >> between r224550 and r224655 have broken my tinderbox setup. It had a > >> tmpfs filesystem mounted at /T and a UFS filesystem mounted at /U, > >> and, when setting up the tinderbox, performed: > >> > >> mkdir /U/u1 > >> mkdir /U/u2 > >> mkdir /T/t1 > >> mount -t nullfs /T/t1 /U/u1 > >> mkdir-p /U/u1/u3/u4 > >> mount -t nullfs /U/u2 /U/u1/u3/u4 > >> ... > >> > >> This worked at r224550 and before. It now fails at the second nullfs > >> mount, with ENOENT("mount_nullfs: No such file or directory"). > > r224615 and r224655 must be reverted. > > > > The reason for your trouble is that nullfs cannot cache any vnodes, > > thus reclaiming anything that get reference count of 0. This interacts > > badly with VOP_VNTOCNP() which has to operate on the vnodes with > > zero refcount, since we cannot decrement refcount under the namecache > > lock. > > > > Trying to update vptocnp(9) interface is too intrusive change for freeze > > period. > > >=20 >=20 > Thank you for the analysis, it will make fixing this problem locally a > bit easier, while you sort it out. Does 224614 have a bearing on this > problem, as well as 224615? >=20 > b. You are right, r224614 and r224655 are revisions that shall be reverted. --C2H3fAq9VP7LQDT/ Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (FreeBSD) iEYEARECAAYFAk492xcACgkQC3+MBN1Mb4gE0ACfXKSWa1qumMZYKYwKnVUE8qi8 6BcAniUBvzovjkTzSVN4HI8cU4p4YEx7 =42Yh -----END PGP SIGNATURE----- --C2H3fAq9VP7LQDT/--