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=-8.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 759F2C43331 for ; Tue, 12 Nov 2019 12:43:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E2212084E for ; Tue, 12 Nov 2019 12:43:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="kWXU6OKg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727077AbfKLMnO (ORCPT ); Tue, 12 Nov 2019 07:43:14 -0500 Received: from mout.gmx.net ([212.227.15.15]:59357 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725919AbfKLMnO (ORCPT ); Tue, 12 Nov 2019 07:43:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1573562515; bh=8gSq4Hf0Q2BntII+T3h2Rbbbcq2YVYB6HDMCTRS6CcM=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=kWXU6OKgEjDYVRO12AVWfPiVdMmV6nroIQJOFUPHa6CL67Vkgt1xi32aILb+0bRQ1 T7Rpxaxx79x+XuAz+nElRl99HL3AFIHC4dk46D6hRmEYF9LIrCdPLoa4Qh2LDHbOkR CkUABkL7jUjk7oVKPEMhZihGHcqcuQXMXCQ7SVjM= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([13.231.109.76]) by mail.gmx.com (mrgmx005 [212.227.17.184]) with ESMTPSA (Nemesis) id 1Mdeb5-1hvRn13P97-00ZiHg; Tue, 12 Nov 2019 13:41:55 +0100 Subject: Re: [PATCH 5/5] btrfs: remove final BUG_ON() in close_fs_devices() To: Johannes Thumshirn , David Sterba Cc: Linux BTRFS Mailinglist References: <20191112122416.30672-1-jthumshirn@suse.de> <20191112122416.30672-6-jthumshirn@suse.de> From: Qu Wenruo Message-ID: Date: Tue, 12 Nov 2019 20:41:50 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191112122416.30672-6-jthumshirn@suse.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:4ePeim3t0mO00F67LM4KrGrnJAloz+CN09CoFE2ix6sH8WLyL6P LwCqUt+4TJLVi/5I8EYLO3623lqV0PNUm1L6fwulndHXWT5+ShO7RZFOswn+WsjbWykFfMZ DwoHK9RwV8WGEsB5l8bwnPhbC9nkdzgH0DoHhLqbLwWWbVSX21yEJlhiR9tq41NgkMMH+l3 SFsRMWGHh7/jtpcm1+gWA== X-UI-Out-Filterresults: notjunk:1;V03:K0:jAaZ99ruRKg=:JOygaF+KHsKxkPd0odFmqJ bLCP135bhSJj4iL79QUGFlZtm3WUYMVXXRGVk32lTC84/OCHKxoKq53IlKw9UwVUlpE1PxKQk PdXZU8TGbP41FwGm7Btz7O+axOO/26D/wV28Zyx1GjL33DoVMOgrC03vVYpU/GKD0IrqT5WhP chcg7OAJz5L7cCED9FGoEW/s/PngNVrwZPAuxgH1GUmkCuZqu7YF0jiR1s1kOJIIElkbt//vF rM/2IHyxJAHd0XnbImmQxnTrwlXOMBFfq8dLVqZ7dVyWLPrqzyWLgTojPL7zDWirxGHW3/WuR K+H+oKkXxhw3mhxfj4bLAYzVSlbbFVpeTenDJWCBX85+EfNECNGF8zg/0C2XbfXqklCRHZzjE x5jq3zfIJhjaCLJxlzCtB6abMGOdKkQT9AaKD8W//yWbTQM49ofyYXY50vODYv9wIq/ikawOl drBrLSod+sP6KplHG14TYtRIe9Zmp2I4Lf+ZMtR92N+XG5qn2dbECC29sJ2by5bhIWZwEHYiy MRoTWpIOwsEZsqyVyecpxqIYJkpCt4yo4+6f1Z9H9qHY267Io6Eg+OaflZ7mxhm4eSb3FyoSL tJYaWOFKw8742WVQK0b/QGB3uml4kTy/XXEAxyhvvPZVZfHcRBaxYL57Wgu7Daha9ZxJv/zOw 9U1lLzfP4pxGkSUBuTDFHcw6jN+zcm1W5WZbXyYRsTsUHXsNfNqasoBDFOQI7BkFcm1CDNlkd MJmedGc6J/9GhB3A/6AOC3i7h+yl2q8oijbiEuV5aWPCzHu3mVA7K6Xm/9B10VG5DgL5QeMDp RQt3scJjIYJ0IJIOJfS+Ysszmm9R//h02P6RXbMxgwzezymP7t/C45ZVSYk2dF8pE4px87Pxo 8pf2IGPzogXDIYnEikoHipeaiIPOB8/zKVKoCG4H9jlerHwXVkPTNHnlmbX6i1fjiios/kHfb bt52VItK/QHSEKKWPLdVigwlIqSkvx0rSKqhCD1lg6NdP5Hbr7SuA+8lGUi3Oadtf/cZ8hSd4 ddBkysWTkrYLGVW0Dg68970G5qNMw9EnRGP5izzrAMH4jIkFSU0VM+oTD9vRLXwv7cOuuvMel GY3IJnZxADe6M3vIY0uy2SWjdU2cX2eRpX1WkkxM6QYPOwujeGdFXtI1zecBMChnIplhSjPZ3 o4K11yBugxrJOfH03aL3ELdZb4EWbor7zJUXvX8zt9382EzwsZc3UIsSP5YNTAKrPbDFTOdEF G8yMkgyyxEP+Jj3yESwuks51e/9TmJEn8hmmby6p9fSdAbBsTHEimQHqxHyk= Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2019/11/12 =E4=B8=8B=E5=8D=888:24, Johannes Thumshirn wrote: > Now that the preparation work is done, remove the temporary BUG_ON() in > close_fs_devices() and return an error instead. > > Signed-off-by: Johannes Thumshirn > --- > fs/btrfs/volumes.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index be1fd935edf7..844333b96075 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -1128,7 +1128,12 @@ static int close_fs_devices(struct btrfs_fs_devic= es *fs_devices) > mutex_lock(&fs_devices->device_list_mutex); > list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) = { > ret =3D btrfs_close_one_device(device); > - BUG_ON(ret); /* -ENOMEM */ > + if (ret) { > + mutex_unlock(&fs_devices->device_list_mutex); > + return ret; > + } > + fs_devices->opened--; > + fs_devices->seeding--; This seeding-- doesn't look safe to me. =46rom what I see, fs_devices->seeding seems to be bool value (0 or 1). Wouldn't this seeding-- underflow? Thanks, Qu > } > mutex_unlock(&fs_devices->device_list_mutex); > >