Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751741AbdF1V3R (ORCPT ); Wed, 28 Jun 2017 17:29:17 -0400 Received: from verein.lst.de ([213.95.11.211]:51629 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751551AbdF1V3J (ORCPT ); Wed, 28 Jun 2017 17:29:09 -0400 Date: Wed, 28 Jun 2017 23:29:08 +0200 From: Christoph Hellwig To: Shaohua Li Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, tj@kernel.org, gregkh@linuxfoundation.org, hch@lst.de, axboe@fb.com, rostedt@goodmis.org, lizefan@huawei.com, Kernel-team@fb.com, Shaohua Li Subject: Re: [PATCH V4 10/12] block: call __bio_free in bio_endio Message-ID: <20170628212908.GA19350@lst.de> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 804 Lines: 16 On Wed, Jun 28, 2017 at 09:30:00AM -0700, Shaohua Li wrote: > From: Shaohua Li > > bio_free isn't a good place to free cgroup/integrity info. There are a > lot of cases bio is allocated in special way (for example, in stack) and > never gets called by bio_put hence bio_free, we are leaking memory. This > patch moves the free to bio endio, which should be called anyway. The > __bio_free call in bio_free is kept, in case the bio never gets called > bio endio. > > This assumes ->bi_end_io() doesn't access cgroup/integrity info, which > seems true in my audit. Otherwise, we probably must add a flag to > distinguish if bio will be called by bio_put. bio_integrity_endio -> bio_integrity_verify_fn -> bio_integrity_process access the integrity data, so I don't think this works as-is.