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Wed, 23 Dec 2020 03:07:07 -0500 Received: by smtp.corp.redhat.com (Postfix) id 3636C1004036; Wed, 23 Dec 2020 08:07:07 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast06.extmail.prod.ext.rdu2.redhat.com [10.11.55.22]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 320E5110F0D9 for ; Wed, 23 Dec 2020 08:06:58 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C625D186E120 for ; Wed, 23 Dec 2020 08:06:58 +0000 (UTC) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-501-WdOCD2gyP4uNBDm2omCkYg-1; Wed, 23 Dec 2020 03:06:56 -0500 X-MC-Unique: WdOCD2gyP4uNBDm2omCkYg-1 Received: by verein.lst.de (Postfix, from userid 2407) id 407DE67373; Wed, 23 Dec 2020 09:06:54 +0100 (CET) Date: Wed, 23 Dec 2020 09:06:53 +0100 From: Christoph Hellwig To: Hannes Reinecke , Mike Snitzer , Christoph Hellwig , linux-block@vger.kernel.org, dm-devel@redhat.com, Jens Axboe , Linux Kernel Mailing List , Alasdair G Kergon Message-ID: <20201223080653.GB4974@lst.de> References: <20201222095056.7a5ac0a0@canb.auug.org.au> <20201222131528.GA29822@lst.de> <20201222145327.GC12885@redhat.com> <288d1c58-c0e2-9d6f-4816-48c66536fe8b@suse.de> <20201222210604.GD29336@agk.fab.redhat.com> MIME-Version: 1.0 In-Reply-To: <20201222210604.GD29336@agk.fab.redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-loop: dm-devel@redhat.com Subject: Re: [dm-devel] DM's filesystem lookup in dm_get_dev_t() [was: Re: linux-next: manual merge of the device-mapper tree with Linus' tree] X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Tue, Dec 22, 2020 at 09:06:04PM +0000, Alasdair G Kergon wrote: > I have not read the background about whatever the new problem is - I'm > jumping in cold seeing this message - but from the very beginning of > device-mapper we have strongly recommended that userspace supplies the > block device in the form MAJOR:MINOR and all our own tools do that. We > guarantee not to deadlock in these places when this is done. > > We also accept the device in the form of a path name as we know there > are times when this is safe and convenient, but then we offer no > guarantees - we place the responsibility upon userspace only to do this > when it knows it is safe to do so i.e. no race and no deadlock. 644bda6f346038bce7ad3ed48f7044c10dde6d47 changes that by accepting all kinds of weirdo formats :( -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel 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=BAYES_00, 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 4895FC433DB for ; Wed, 23 Dec 2020 08:07:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 015D9207C9 for ; Wed, 23 Dec 2020 08:07:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727919AbgLWIHg (ORCPT ); Wed, 23 Dec 2020 03:07:36 -0500 Received: from verein.lst.de ([213.95.11.211]:33710 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727622AbgLWIHg (ORCPT ); Wed, 23 Dec 2020 03:07:36 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id 407DE67373; Wed, 23 Dec 2020 09:06:54 +0100 (CET) Date: Wed, 23 Dec 2020 09:06:53 +0100 From: Christoph Hellwig To: Hannes Reinecke , Mike Snitzer , Christoph Hellwig , linux-block@vger.kernel.org, dm-devel@redhat.com, Jens Axboe , Linux Kernel Mailing List , Alasdair G Kergon Subject: Re: [dm-devel] DM's filesystem lookup in dm_get_dev_t() [was: Re: linux-next: manual merge of the device-mapper tree with Linus' tree] Message-ID: <20201223080653.GB4974@lst.de> References: <20201222095056.7a5ac0a0@canb.auug.org.au> <20201222131528.GA29822@lst.de> <20201222145327.GC12885@redhat.com> <288d1c58-c0e2-9d6f-4816-48c66536fe8b@suse.de> <20201222210604.GD29336@agk.fab.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201222210604.GD29336@agk.fab.redhat.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Dec 22, 2020 at 09:06:04PM +0000, Alasdair G Kergon wrote: > I have not read the background about whatever the new problem is - I'm > jumping in cold seeing this message - but from the very beginning of > device-mapper we have strongly recommended that userspace supplies the > block device in the form MAJOR:MINOR and all our own tools do that. We > guarantee not to deadlock in these places when this is done. > > We also accept the device in the form of a path name as we know there > are times when this is safe and convenient, but then we offer no > guarantees - we place the responsibility upon userspace only to do this > when it knows it is safe to do so i.e. no race and no deadlock. 644bda6f346038bce7ad3ed48f7044c10dde6d47 changes that by accepting all kinds of weirdo formats :(