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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5229C433EF for ; Sun, 6 Mar 2022 22:43:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E7CE98D0002; Sun, 6 Mar 2022 17:43:54 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E051D8D0001; Sun, 6 Mar 2022 17:43:54 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C7E548D0002; Sun, 6 Mar 2022 17:43:54 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id B3E7F8D0001 for ; Sun, 6 Mar 2022 17:43:54 -0500 (EST) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 777262322A for ; Sun, 6 Mar 2022 22:43:54 +0000 (UTC) X-FDA: 79215440388.15.0D169A6 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf15.hostedemail.com (Postfix) with ESMTP id 45F04A0002 for ; Sun, 6 Mar 2022 22:43:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=+i9vRmNI7+eHzPPl/RuOFsNSwoWFlLZKj3k3cgvkPwE=; b=C7wEujQbkNSEL8UesYZpUV1Owu 5y5vzvRLA9jhhEy3AtVVgWpwbbHaPsCo5A/wYRNy+lJDxAg7gPm6kHeHB+b/2X7tVihHQ1+Wh72Tn RvWNFEYZgum5b1z+ZKpf0mF4Ge8XXlI5X+rbSBmslYhDGMc0PNpXt+zDNP/3EVJ9hDcAybpYQ5Zyb j5j7LEGQZHGR1bi8fvYz+db4QRDs6k/aVLppY9CfeBfPvoevFmwRReAxGu2Vd0KABcvks6N6sdx1d XfJe7O5Zo0QKkhB+1K1wyL3WV9NaZ5ZaZp8DQ7CGhzYQ8Dh7QzNM2aGJ5dYTiP9YgNsYWT9a8BGUI LjpaIgfQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nQzb9-00EfoG-RJ; Sun, 06 Mar 2022 22:43:32 +0000 Date: Sun, 6 Mar 2022 22:43:31 +0000 From: Matthew Wilcox To: Jarkko Sakkinen Cc: Greg Kroah-Hartman , linux-mm@kvack.org, Dave Hansen , Nathaniel McCallum , Reinette Chatre , Andrew Morton , linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org, Florian Fainelli , Thomas Bogendoerfer , Matthew Auld , Thomas =?iso-8859-1?Q?Hellstr=F6m?= , Daniel Vetter , Jason Ekstrand , Chris Wilson , Maarten Lankhorst , Tvrtko Ursulin , Shakeel Butt , Vasily Averin , zhangyiru , Alexander Mikhalitsyn , Alexey Gladkov , linux-mips@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, codalist@coda.cs.cmu.edu, linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH RFC 1/3] mm: Add f_ops->populate() Message-ID: References: <20220306053211.135762-1-jarkko@kernel.org> <20220306053211.135762-2-jarkko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 45F04A0002 X-Stat-Signature: p3ps4z76xfqyyhtd9yu9z44nocauwnft Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=C7wEujQb; spf=none (imf15.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Rspam-User: X-HE-Tag: 1646606633-128186 X-Bogosity: Ham, tests=bogofilter, spamicity=0.003942, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Mar 06, 2022 at 07:02:57PM +0200, Jarkko Sakkinen wrote: > So can I conclude from this that in general having populate available for > device memory is something horrid, or just the implementation path? You haven't even attempted to explain what the problem is you're trying to solve. You've shown up with some terrible code and said "Hey, is this a good idea". No, no, it's not.