From owner-freebsd-stable@FreeBSD.ORG Thu Jun 7 06:25:28 2007 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 26B1716A46B; Thu, 7 Jun 2007 06:25:28 +0000 (UTC) (envelope-from doconnor@gsoft.com.au) Received: from cain.gsoft.com.au (cain.gsoft.com.au [203.31.81.10]) by mx1.freebsd.org (Postfix) with ESMTP id 664A413C44C; Thu, 7 Jun 2007 06:25:27 +0000 (UTC) (envelope-from doconnor@gsoft.com.au) Received: from inchoate.gsoft.com.au (inchoate.gsoft.com.au [203.31.81.61]) (authenticated bits=0) by cain.gsoft.com.au (8.13.8/8.13.8) with ESMTP id l576PPxf005769 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 7 Jun 2007 15:55:25 +0930 (CST) (envelope-from doconnor@gsoft.com.au) From: "Daniel O'Connor" To: Tim Kientzle Date: Thu, 7 Jun 2007 15:55:21 +0930 User-Agent: KMail/1.9.5 References: <20070601114047.z6qgi686os4ogw4o@server.yirdis.nl> <20070606095820.83tast6s0804osos@server.yirdis.nl> <46679117.5060909@freebsd.org> In-Reply-To: <46679117.5060909@freebsd.org> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart2149425.jFjPhz8vSj"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200706071555.22707.doconnor@gsoft.com.au> X-Spam-Score: -3.977 () ALL_TRUSTED,BAYES_00 X-Scanned-By: MIMEDefang 2.58 on 203.31.81.10 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Robin Gruyters , freebsd-stable@freebsd.org Subject: Re: Unrecognized archive format with RELENG_6_2 and RELENG_6 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: Thu, 07 Jun 2007 06:25:28 -0000 --nextPart2149425.jFjPhz8vSj Content-Type: multipart/mixed; boundary="Boundary-01=_ST6ZGJeTQapGTpv" Content-Transfer-Encoding: 7bit Content-Disposition: inline --Boundary-01=_ST6ZGJeTQapGTpv Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Thursday 07 June 2007 14:31, Tim Kientzle wrote: > sudo ktrace tar -tf /dev/sa0 > > Then run 'kdump | less' and see if you can find a pair of 'lseek' > calls, which will probably look something like this: > > 53127 bsdtar CALL lseek(0x3,0,0,0,0x1) > 53127 bsdtar RET lseek 6656000/0x659000 > 53127 bsdtar CALL lseek(0x3,0,0x70800,0,0x1) > 53127 bsdtar RET lseek 7116800/0x6c9800 I get the following.. 5378 bsdtar CALL lseek(0x3,0,0,0x1) 5378 bsdtar RET lseek 51200/0xc800 5378 bsdtar CALL lseek(0x3,0,0x2f800,0x1) 5378 bsdtar RET lseek 245760/0x3c000 > I believe you'll find that the SCSI tape driver > in 6.2 lies: It does not actually seek, but the > two lseek calls return different values. As a result, > tar believes that the body of the tar entry has been > skipped when it hasn't. This doesn't occur with tar > from 6.1 because the seek optimization was added after > that; it doesn't happen with compressed archives because > you cannot seek in compressed files. Hmm, so I wonder if this hypothesis can be tested by asking for the=20 position of the tape using mt before and after the seek.. Quick kludge attached.. [cain 15:54] ~ >./test /dev/nsa0: logical block location 0 /dev/nsa0: hardware block location 0 Current pos is 0 /dev/nsa0: logical block location 0 /dev/nsa0: hardware block location 0 Current pos is 100 /dev/nsa0: logical block location 0 /dev/nsa0: hardware block location 0 =2D-=20 Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C --Boundary-01=_ST6ZGJeTQapGTpv-- --nextPart2149425.jFjPhz8vSj Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQBGZ6TS5ZPcIHs/zowRAmN8AJ9gv63hOJeThRAMy83vyYb6ZRrCXgCfaNfu yNh2BkfDSX2+dipZLlequxA= =BmN2 -----END PGP SIGNATURE----- --nextPart2149425.jFjPhz8vSj--