From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Thiago Jung Bauermann To: Dan Williams Cc: linux-block@vger.kernel.org, Andi Kleen , Jan Kara , Rabin Vincent , linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, Jens Axboe , Wei Fang , linux-fsdevel@vger.kernel.org, Christoph Hellwig Subject: Re: [RFC PATCH v2 0/2] block: fix backing_dev_info lifetime Date: Mon, 23 Jan 2017 19:17:21 -0200 In-Reply-To: <148375097100.37020.495735345355345658.stgit@dwillia2-desk3.amr.corp.intel.com> References: <148375097100.37020.495735345355345658.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Message-Id: <7780787.RVFXFXDN3H@morokweng> Sender: linux-kernel-owner@vger.kernel.org List-ID: Hello Dan, Am Freitag, 6. Januar 2017, 17:02:51 BRST schrieb Dan Williams: > v1 of these changes [1] was a one line change to bdev_get_queue() to > prevent a shutdown crash when del_gendisk() races the final > __blkdev_put(). > > While it is known at del_gendisk() time that the queue is still alive, > Jan Kara points to other paths [2] that are racing __blkdev_put() where > the assumption that ->bd_queue, or inode->i_wb is valid does not hold. > > Fix that broken assumption, make it the case that if you have a live > block_device, or block_device-inode that the corresponding queue and > inode-write-back data is still valid. > > These changes survive a run of the libnvdimm unit test suite which puts > some stress on the block_device shutdown path. I realize that the kernel test robot found problems with this series, but FWIW it fixes the bug mentioned in [2]. > [1]: http://marc.info/?l=linux-block&m=148366637105761&w=2 > [2]: http://www.spinics.net/lists/linux-fsdevel/msg105153.html -- Thiago Jung Bauermann IBM Linux Technology Center