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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 3A4DEC43331 for ; Wed, 13 Nov 2019 15:05:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0D65E2245B for ; Wed, 13 Nov 2019 15:05:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727874AbfKMPFU (ORCPT ); Wed, 13 Nov 2019 10:05:20 -0500 Received: from mx2.suse.de ([195.135.220.15]:40264 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727820AbfKMPFU (ORCPT ); Wed, 13 Nov 2019 10:05:20 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 9142FB2DB; Wed, 13 Nov 2019 15:05:18 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 2A566DA7E8; Wed, 13 Nov 2019 16:05:22 +0100 (CET) Date: Wed, 13 Nov 2019 16:05:22 +0100 From: David Sterba To: Johannes Thumshirn Cc: David Sterba , Qu Wenru , Linux BTRFS Mailinglist Subject: Re: [PATCH v2 0/7] remove BUG_ON()s in btrfs_close_one_device() Message-ID: <20191113150522.GE3001@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Johannes Thumshirn , David Sterba , Qu Wenru , Linux BTRFS Mailinglist References: <20191113102728.8835-1-jthumshirn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191113102728.8835-1-jthumshirn@suse.de> 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 Wed, Nov 13, 2019 at 11:27:21AM +0100, Johannes Thumshirn wrote: > This series attempts to remove the BUG_ON()s in btrfs_close_one_device(). > Therefore some reorganization of btrfs_close_one_device() and > close_fs_devices() was needed. > > Forthermore a new BUG_ON() had to be temporarily introduced but is removed > again in the last patch of theis series. > > Although it is generally legal to return -ENOMEM on umount(2), the error > handling up until close_ctree() as neither close_ctree() nor btrfs_put_super() > would be able to handle the error. > > This series has passed fstests without any deviation from the baseline and > also the new error handling was tested via error injection using this snippet: > > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index 7c55169c0613..c58802c9c39c 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -1069,6 +1069,9 @@ static int btrfs_close_one_device(struct btrfs_device *device) > > new_device = btrfs_alloc_device(NULL, &device->devid, > device->uuid); > + btrfs_free_device(new_device); > + pr_err("%s() INJECTING -ENOMEM\n", __func__); > + new_device = ERR_PTR(-ENOMEM); > if (IS_ERR(new_device)) > return PTR_ERR(new_device); > > Changes to v1: > > Fixed the decremt of btrfs_fs_devices::seeding. > > In addition to this, I've added two patches changing btrfs_fs_devices::seeding > and btrfs_fs_devices::rotating to bool, as they are in fact used as booleans. > > Johannes Thumshirn (7): > btrfs: decrement number of open devices after closing the device not > before > btrfs: handle device allocation failure in btrfs_close_one_device() > btrfs: handle allocation failure in strdup > btrfs: handle error return of close_fs_devices() > btrfs: remove final BUG_ON() in close_fs_devices() > btrfs: change btrfs_fs_devices::seeing to bool > btrfs: change btrfs_fs_devices::rotating to bool I'll add the last 2 for now as they're obviously correct, the rest has some questions that I'd like to clarify before merging.