From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752392AbbDEHZY (ORCPT ); Sun, 5 Apr 2015 03:25:24 -0400 Received: from mail-pd0-f169.google.com ([209.85.192.169]:34739 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751114AbbDEHZV (ORCPT ); Sun, 5 Apr 2015 03:25:21 -0400 From: Ming Lei To: Jens Axboe , linux-kernel@vger.kernel.org, Christoph Hellwig , Tejun Heo Cc: Andrew Morton , Alexander Viro , Jarod Wilson , David Herrmann , Markus Pargmann , nbd-general@lists.sourceforge.net, Stefan Haberland , Sebastian Ott , Fabian Frederick , linux-s390@vger.kernel.org Subject: [PATCH 0/6] block: reread partitions changes and fix for loop Date: Sun, 5 Apr 2015 15:24:42 +0800 Message-Id: <1428218688-4092-1-git-send-email-ming.lei@canonical.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Recently there are several reports about loop partition scanning failure[1][2]. For loop, the root cause is one ABBA and one AA lock dependency issue, and the two are fixed by patch 2 and patch 3 each. Another reason is from the trylock in blkdev_reread_part(), which may cause partition scanning failure too sometimes when another task is holding the bd_mutex. In the discussion[1], both Tejun and Christoph suggests to replace the trylock with mutex_lock in blkdev_reread_part(), also Christoph suggests to export blkdev_reread_part. Following the discussion, this patchset exports blkdev_reread_part(), and introduces blkdev_reread_part_nolock() for fixing loop's AA lock issue. Then ioctl_by_bdev(BLKRRPART) in loop, nbd and dasd is replaced with blkdev_reread_part(). In the last patch, trylock in __blkdev_reread_part() is replaced with mutex_lock, and some analysis is provided about the conversion. [1], https://lkml.org/lkml/2015/1/26/137 [2], https://lkml.org/lkml/2015/3/31/888 Thanks, Ming Lei