From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD019C3F2CD for ; Fri, 28 Feb 2020 16:20:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87B802467B for ; Fri, 28 Feb 2020 16:20:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725886AbgB1QUi (ORCPT ); Fri, 28 Feb 2020 11:20:38 -0500 Received: from mx2.suse.de ([195.135.220.15]:41432 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725730AbgB1QUi (ORCPT ); Fri, 28 Feb 2020 11:20:38 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 04F85B331; Fri, 28 Feb 2020 16:20:37 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id A2E3EDA79B; Fri, 28 Feb 2020 17:20:16 +0100 (CET) Date: Fri, 28 Feb 2020 17:20:16 +0100 From: David Sterba To: fdmanana@kernel.org Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH] Btrfs: fix crash during unmount due to race with delayed inode workers Message-ID: <20200228162016.GP2902@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, fdmanana@kernel.org, linux-btrfs@vger.kernel.org References: <20200228130436.26128-1-fdmanana@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200228130436.26128-1-fdmanana@kernel.org> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Feb 28, 2020 at 01:04:36PM +0000, fdmanana@kernel.org wrote: > From: Filipe Manana > > During unmount we can have a job from the delayed inode items work queue > still running, that can lead to at least two bad things_ > > 1) A crash, because the worker can try to create a transaction just > after the fs roots were freed; > > 2) A transaction leak, because the worker can create a transaction > before the fs roots are freed and just after we committed the last > transaction and after we stopped the transaction kthread. ... > + * This is a very rare case. Added to misc-next, thanks. I'll tag it for stable but will not put to 5.6-rc queue given that it's very rare, unless requested.