Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757099Ab0GASNm (ORCPT ); Thu, 1 Jul 2010 14:13:42 -0400 Received: from kroah.org ([198.145.64.141]:60036 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754914Ab0GASKs (ORCPT ); Thu, 1 Jul 2010 14:10:48 -0400 X-Mailbox-Line: From gregkh@clark.site Thu Jul 1 10:28:57 2010 Message-Id: <20100701172857.134213426@clark.site> User-Agent: quilt/0.48-10.1 Date: Thu, 01 Jul 2010 10:26:57 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, NeilBrown Subject: [08/23] md: Fix read balancing in RAID1 and RAID10 on drives > 2TB In-Reply-To: <20100701175134.GA2098@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2118 Lines: 61 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: NeilBrown commit af3a2cd6b8a479345786e7fe5e199ad2f6240e56 upstream. read_balance uses a "unsigned long" for a sector number which will get truncated beyond 2TB. This will cause read-balancing to be non-optimal, and can cause data to be read from the 'wrong' branch during a resync. This has a very small chance of returning wrong data. Reported-by: Jordan Russell Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid1.c | 4 ++-- drivers/md/raid10.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -413,7 +413,7 @@ static void raid1_end_write_request(stru */ static int read_balance(conf_t *conf, r1bio_t *r1_bio) { - const unsigned long this_sector = r1_bio->sector; + const sector_t this_sector = r1_bio->sector; int new_disk = conf->last_used, disk = new_disk; int wonly_disk = -1; const int sectors = r1_bio->sectors; @@ -429,7 +429,7 @@ static int read_balance(conf_t *conf, r1 retry: if (conf->mddev->recovery_cp < MaxSector && (this_sector + sectors >= conf->next_resync)) { - /* Choose the first operation device, for consistancy */ + /* Choose the first operational device, for consistancy */ new_disk = 0; for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -490,7 +490,7 @@ static int raid10_mergeable_bvec(struct */ static int read_balance(conf_t *conf, r10bio_t *r10_bio) { - const unsigned long this_sector = r10_bio->sector; + const sector_t this_sector = r10_bio->sector; int disk, slot, nslot; const int sectors = r10_bio->sectors; sector_t new_distance, current_distance; -- 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/