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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 AE824C55186 for ; Thu, 23 Apr 2020 11:07:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89B712076C for ; Thu, 23 Apr 2020 11:07:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728010AbgDWLHq (ORCPT ); Thu, 23 Apr 2020 07:07:46 -0400 Received: from mx2.suse.de ([195.135.220.15]:47186 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726805AbgDWLHq (ORCPT ); Thu, 23 Apr 2020 07:07:46 -0400 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 1DA16B0B8; Thu, 23 Apr 2020 11:07:43 +0000 (UTC) Date: Thu, 23 Apr 2020 13:07:38 +0200 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Christoph Hellwig Cc: Qian Cai , Jens Axboe , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , linux-block@vger.kernel.org, linux-s390@vger.kernel.org, LKML Subject: Re: s390 boot woe due to "block: fix busy device checking in blk_drop_partitions" Message-ID: <20200423110738.GA102241@blackbook> References: <20200410054544.GA17923@lst.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="BOKacYhQ+x31HxR3" Content-Disposition: inline In-Reply-To: <20200410054544.GA17923@lst.de> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --BOKacYhQ+x31HxR3 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi. On Fri, Apr 10, 2020 at 07:45:44AM +0200, Christoph Hellwig wrote: > @@ -496,7 +496,7 @@ int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev) > - if (bdev->bd_part_count || bdev->bd_openers) > + if (bdev->bd_part_count || bdev->bd_openers > 1) > return -EBUSY; I noticed this (and the previous patch) change unmasks race between ioctl(LOOP_SET_STATUS64, ... lo_flags=LO_FLAGS_PARTSCAN ...) and udev processing loop device uevents. See [1] for details. Should the condition be changed in the case of newly setup loop devices? (Or shouldn't the ioctl propagate EBUSY in its return value?) Thanks, Michal [1] https://bugzilla.opensuse.org/show_bug.cgi?id=1169932 --BOKacYhQ+x31HxR3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEEoQaUCWq8F2Id1tNia1+riC5qSgFAl6hdvAACgkQia1+riC5 qSgT0A/9HF8wBP+q81PKssmN3OAiHSEBVgWuK2oRpZDemVZOk7Ju4HOdfgFW//7y 3HREuHE2FTBMSvd+kp6B8PRSA8Qzw1GaJEHRCeh2+3nfUT4UmMDlJiw9mB7oN2pH fmVdjfTWhsdEx1FhOTvKnPWzwrWJIdhCyqB8xnRzosIdCaeXPM7HLwbSG64GZ/VE biTAGgAGXZGXexNVfi0UWbxll6td64pNFr+XMoToCzRNUvyxu9jMDBvyyAB7F5et pOGedkxdysYujjFle3o3Lw6ifJ+dZh3BLgZfFWAPW59J/b6ZTi1k4vzv40vPdSju fho2c4Q3QPPFC0o5SMws3Vu92woJfrzRbUdzqSpnCrXZY//8/0fyuuPyjgBEglDs daxWBKhAdrAb4tsIul+jc3nSY7KGCgy1Eef7rU7TC5rduJ0a65dco4POXHL1CGk6 pppFxjAmupe6tevT/C7HtSWOaSvoWkaKPq7MQ0VSEMTyuErYhdv7402+IzSjLuxJ z6uG/k52yUce51P1z8LW57BRiHW0rBB4Qs6nSN3qu2O+Hul2OBZAgCp5qpzYcIBG qH0L4V39Q1U6PILsDkQYX9GLM3hEWf4LaSg7xCYcjYLn3YbXXMiUzmVvl/igXbBe zBFiBwslvrRk/71wSdK7xYT1NbnqSNcRJLe6ePYnCNP8p2i77dI= =pl+J -----END PGP SIGNATURE----- --BOKacYhQ+x31HxR3--