From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Tran Subject: [PATCH] raid1: set bi_idx after bio cloning Date: Fri, 13 May 2005 16:39:02 -0500 Message-ID: <1116020307.6557.34.camel@langvan2.homenetwork> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: neilb@cse.unsw.edu.au, axboe@suse.de, linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi Neil et al, The scenario: Having LVM (striped) volumes on top of 2 raid1 devices The problem: Corruption in building the scatter gather list for device driver (see /drivers/block/blk_rq_map_sg() function) In DM code, a bio sometimes can be split into several clones and the clones' bi_idx is set accordingly by DM. MD raid1 also clones bio but does not adjust bi_idx. The problem can be fixed in either __bio_clone() or the caller of bio_clone(). I chose to fix raid1. --- linux-2.6.12-rc4-orig/drivers/md/raid1.c 2005-05-10 13:35:06.000000000-0500 +++ linux-2.6.12-rc4-patch/drivers/md/raid1.c 2005-05-13 15:41:43.000000000-0500 @@ -577,6 +577,7 @@ r1_bio->bios[rdisk] = read_bio; + read_bio->bi_idx = bio->bi_idx; read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; read_bio->bi_bdev = mirror->rdev->bdev; read_bio->bi_end_io = raid1_end_read_request; -- Regards, Mike T.