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=-8.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 D2645C4363D for ; Fri, 25 Sep 2020 08:22:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71620207C4 for ; Fri, 25 Sep 2020 08:22:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="VozTjWaD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727461AbgIYIWY (ORCPT ); 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <34706a92-3153-20d7-2a22-cbc39b1980eb@suse.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 24.09.20 г. 13:21 ч., Nikolay Borisov wrote: > > > On 24.09.20 г. 13:11 ч., Anand Jain wrote: >> commit 343694eee8d8 (btrfs: switch seed device to list api), missed to >> check if the last arg (seed) is true in the function btrfs_find_device(). >> This arg tells whether to traverse through the seed device list or not. >> >> This means after the above commit the arg is always true, and the parent >> function which set this arg to false aren't effective. >> >> So we don't worry about the parent functions which set the last arg to >> true, instead there is only one parent with calling btrfs_find_device >> with the last arg false in device_list_add(). >> >> But in fact, even the device_list_add() has no purpose that it has to set >> the last arg to false. Because the fs_devices always points to the >> device's fs_devices. So with the devid+uuid matching, it shall find the >> btrfs_device and returns. So naturally, it won't traverse through the >> seed fs_devices (if) present. >> >> So this patch makes it official that we don't need the last arg in the >> function btrfs_find_device() and it shall always traverse through the >> seed device list. >> >> Signed-off-by: Anand Jain > > IMO the changelog could be vastly simplified by stating that following > commit 343694eee8d8 the seed argument is no longer used and can simply > be removed. > > In any case > > Reviewed-by: Nikolay Borisov > > Actually I went back and it seems that I accidentally removed the portion of btrfs_find_device() which was predicated on seed bool parameter being true or false. So the correct thing to do is really to send a patch which adds it back and consider it a fix (i.e adding a Fixes: tag as well). OTOH - does it really make any difference? SO what if btrfs_find_device returns a device from fs_devices->seed_list in device_list_add (which is called only from device scan)?