From owner-freebsd-fs@FreeBSD.ORG Fri Dec 26 01:47:31 2014 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 617AE7B; Fri, 26 Dec 2014 01:47:31 +0000 (UTC) Received: from vps.rulingia.com (vps.rulingia.com [103.243.244.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "vps.rulingia.com", Issuer "CAcert Class 3 Root" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id D11932915; Fri, 26 Dec 2014 01:47:29 +0000 (UTC) Received: from server.rulingia.com (c220-239-242-83.belrs5.nsw.optusnet.com.au [220.239.242.83]) by vps.rulingia.com (8.14.9/8.14.9) with ESMTP id sBQ1gS5B036442 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 26 Dec 2014 12:42:34 +1100 (AEDT) (envelope-from peter@rulingia.com) X-Bogosity: Ham, spamicity=0.000000 Received: from server.rulingia.com (localhost.rulingia.com [127.0.0.1]) by server.rulingia.com (8.14.9/8.14.9) with ESMTP id sBQ1gKO2002041 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 26 Dec 2014 12:42:20 +1100 (AEDT) (envelope-from peter@server.rulingia.com) Received: (from peter@localhost) by server.rulingia.com (8.14.9/8.14.9/Submit) id sBQ1gKIs002040; Fri, 26 Dec 2014 12:42:20 +1100 (AEDT) (envelope-from peter) Date: Fri, 26 Dec 2014 12:42:20 +1100 From: Peter Jeremy To: Rick Macklem Subject: Re: "panic: len 0" on NFS read Message-ID: <20141226014220.GA2001@server.rulingia.com> References: <20141225233742.GA3385@server.rulingia.com> <1000783981.2374019.1419556100933.JavaMail.root@uoguelph.ca> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="1yeeQ81UyVL57Vl7" Content-Disposition: inline In-Reply-To: <1000783981.2374019.1419556100933.JavaMail.root@uoguelph.ca> X-PGP-Key: http://www.rulingia.com/keys/peter.pgp User-Agent: Mutt/1.5.23 (2014-03-12) Cc: freebsd-fs@freebsd.org, benno@freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Dec 2014 01:47:31 -0000 --1yeeQ81UyVL57Vl7 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2014-Dec-25 20:08:20 -0500, Rick Macklem wrote: >Peter Jeremy wrote: >> Whilst trying to debug a RPC issue with a NFS tunneling tool, I >> mounted a >> NFS filesystem onto the same host and got a panic when I tried to >> access it. >>=20 >> I'm running FreeBSD/amd64 10-stable r276177. >>=20 >> I mounted the filesystem with: >> # mount -o udp,nfsv3 $(hostname):/tank/src92 /dist >>=20 >> (/tank/src92 and / are ZFS) >>=20 >> And then ran: >> $ grep zzzz /dist/* >>=20 >> And got: >> panic: len 0 >r275941 in head changed this KASSERT to allow a 0 length mbuf, so I >don't think the panic is meaningful. >Maybe r275941 should be MFC'd? (I've cc'd benno, who did the commit.) Thanks. I've tried MFCing r275941 and can't reproduce the panic by following the above (though without knowing the exact reason for having a 0-byte mbuf in the chain originally, I can't be sure that I'm getting a 0-byte mbuf in the chain now). --=20 Peter Jeremy --1yeeQ81UyVL57Vl7 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQJ8BAEBCgBmBQJUnLz8XxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXRFRUIyOTg2QzMwNjcxRTc0RTY1QzIyN0Ux NkE1OTdBMEU0QTIwQjM0AAoJEBall6Dkogs0QAEP/2BA5fzMDAuPmUVxN5eGdWVm khrwTYwYCmV19KDrS9TnHCwcATN62bCkryM1dvSiRjEBXQCgSLwVWP8gwOQxpdxk 4KvOyVLQkjh9FGkWO2IIV7X9CUgibTULqPU7UDwm7bNwW0duB5q/iKRFLuPwWZX2 RK8Mt2RpiM+MJOhJualOTb+zob/ijqAtSJ5OtECqztDKtMFcwJNii23d4SfCyQu3 A6wBChnXg5a9JG4OLzCleNB5RLS8OpnGR+3rPTzARKpUxMKFwUrj3gRPvCOIgc4c SJc0Ua91WiX8+zp9xkyAZ+l7gF00ZKHs0XvoDKOsUggENS8kxIQW1CJyf5Zr+hI6 bMEukO2EaSQ46wQaynbMrOJUYz4925qNUf4jRatY2bRl1Za86pz0TnXeJh0/bo0Z bKGRZkgCdWYEjIBc1tQJ96R6e5zTlni5JmpRBfYjS12cP/j46AFCyEaAASm3G3Sa dzIgTVfiVttVATG1ENiihIpMWX7bUL7+D4NCyIkjzNYiZAngnlFt1UwkLNZobxP6 YfLwRedXIL/UHXeeHzotFH6wOUT8jxwibpX8mXklzi4vRhl+pX7FnuFdkAYfEIq/ CSMFCoDTwD86+9vCvwzuQQIeVoYDKUjHjIwQdNgvilsnCiwSQ4SgpN0CSSVK9Asf 7/3VLDtqWZYfbgP7QOf7 =MxsQ -----END PGP SIGNATURE----- --1yeeQ81UyVL57Vl7--