Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422911Ab3CVUWH (ORCPT ); Fri, 22 Mar 2013 16:22:07 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43954 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422768Ab3CVUWF (ORCPT ); Fri, 22 Mar 2013 16:22:05 -0400 Message-ID: <1363983716.3728.42.camel@deadeye.wl.decadent.org.uk> Subject: Re: [PATCH] dm: dm-cache fails to write the cache device in writethrough mode From: Ben Hutchings To: "Darrick J. Wong" Cc: Linus Torvalds , dm-devel@redhat.com, linux-kernel@vger.kernel.org, Heinz Mauelshagen , Joe Thornber , Mike Snitzer , Mikulas Patocka , Paul Taysom , Randy Dunlap , stable@vger.kernel.org Date: Fri, 22 Mar 2013 20:21:56 +0000 In-Reply-To: <20130322201151.GB5357@blackbox.djwong.org> References: <20130322201151.GB5357@blackbox.djwong.org> Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-xL1yf2M+VvuXOU057dBO" X-Mailer: Evolution 3.4.4-2 Mime-Version: 1.0 X-SA-Exim-Connect-IP: 2001:470:1f08:1539:9535:520b:eb30:917a X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2165 Lines: 60 --=-xL1yf2M+VvuXOU057dBO Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2013-03-22 at 13:11 -0700, Darrick J. Wong wrote: > The new writethrough strategy for dm-cache issues a bio to the origin dev= ice, > remaps the bio to the cache device, and issues the bio to the cache devic= e. > However, the block layer modifies bi_sector and bi_size, so we need to pr= eserve > these or else nothing gets written to the cache (bi_size =3D=3D 0). This= fixes the > problem where someone writes a block through the cache, but a subsequent = reread > (from the cache) returns old contents. >=20 > Signed-off-by: Darrick J. Wong > --- [...] This is not the correct way to submit a change to stable. See Documentation/stable_kernel_rules.txt Ben. --=20 Ben Hutchings Make three consecutive correct guesses and you will be considered an expert= . --=-xL1yf2M+VvuXOU057dBO Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIVAwUAUUy9ZOe/yOyVhhEJAQoHvg//Sgjxk/3keq0IR14wAVOFqldqHXYlJ4mf 6rTUfWPLQzxcmPOtOdpRhH8e7tBufe30wTwh/RUmGC9t+vB4U/NzCCwXm5RSl1e6 O5Ur3aoUBBhVw0An/jvcTIXRtYowK9Sc5xDWBsPE6I3QG+jBQB1KkZHdRsbYVJIz bhrhA+ZVitt0OOiSkBwfgm+Zy1I3BEoutnbJuknn5NkAI7zkWhCnSc5k0IZ6PR9+ zMdIzsQB7F96LFJIE9PO/pM+v92cqDLKWPFGRUzrYlQStOF3M3qzdTn1QSUg3bW/ ipsQklsFlHSQFMdedIMjkAFZtkrXssh/LQ38zpGxT8SynCgSfKEm6037AZhVE7eZ kBbr5QcR+iAuq8loZuvG8FXEPJCLYTLC5Wp5bU1ntJyUpNyv25AZETiDdOUcd41N FtRg3hDx21Oo29wxXFAqZIuSgm3YHmfz8whJeZmCWiGlo1dO6QM4ZN4vK6/6/uWT WkxqdUz1OIHK47XbzDTYJFRFs4fOOjbiyjDC8x9lGXdR9FsufAxV3OadwTYlt9xx rnBNrUjrIftb2hoXf8YpTAGMeJK9LzkEPGtTDoJazBZD/VfI9sM1bcutEcDmTSQA m1/pKt0F9LoMJHXxUh0YBvJW73Sz+TwYMt3fIpSYeurEPVRhMnk6DEOqypV4CE0i 91lh8P/QFNw= =nvqL -----END PGP SIGNATURE----- --=-xL1yf2M+VvuXOU057dBO-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/