From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id 2359B6B0003 for ; Tue, 2 Oct 2018 10:44:18 -0400 (EDT) Received: by mail-ed1-f72.google.com with SMTP id k16-v6so1414127ede.6 for ; Tue, 02 Oct 2018 07:44:18 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id r44-v6si1610946edr.198.2018.10.02.07.44.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Oct 2018 07:44:17 -0700 (PDT) Date: Tue, 2 Oct 2018 16:44:13 +0200 From: Johannes Thumshirn Subject: Re: Problems with VM_MIXEDMAP removal from /proc//smaps Message-ID: <20181002144412.GC4963@linux-x5ow.site> References: <20181002100531.GC4135@quack2.suse.cz> <20181002121039.GA3274@linux-x5ow.site> <20181002142959.GD9127@quack2.suse.cz> <20181002143713.GA19845@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181002143713.GA19845@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Hellwig Cc: Jan Kara , Dan Williams , Dave Jiang , linux-nvdimm@lists.01.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-api@vger.kernel.org On Tue, Oct 02, 2018 at 07:37:13AM -0700, Christoph Hellwig wrote: > No, it should not. DAX is an implementation detail thay may change > or go away at any time. Well we had an issue with an application checking for dax, this is how we landed here in the first place. It's not that I want them to do it, it's more that they're actually doing it in all kinds of interesting ways and then complaining when it doesn't work anymore. So it's less of an "API beauty price problem" but more of a "provide a documented way which we won't break" way. Byte, Johannes -- Johannes Thumshirn Storage jthumshirn@suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nurnberg GF: Felix Imendorffer, Jane Smithard, Graham Norton HRB 21284 (AG Nurnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850