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 B56E7C433F5 for ; Mon, 7 Mar 2022 15:57:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 254CC8D0001; Mon, 7 Mar 2022 10:57:05 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 202A08D0002; Mon, 7 Mar 2022 10:57:05 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0B0C28D0001; Mon, 7 Mar 2022 10:57:05 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0117.hostedemail.com [216.40.44.117]) by kanga.kvack.org (Postfix) with ESMTP id EBB938D0001 for ; Mon, 7 Mar 2022 10:57:04 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 99E1F8249980 for ; Mon, 7 Mar 2022 15:57:04 +0000 (UTC) X-FDA: 79218043968.28.266BC7D Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf17.hostedemail.com (Postfix) with ESMTP id BCA4940007 for ; Mon, 7 Mar 2022 15:57:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=WrCk5Zjz4zeQvJI59w3Y1NYye/gptEQDerS0Psr1TZ4=; b=wW7FyJ7wdAgP5ZxLNFEf3eQpn9 s8zqFBSs7eoLCpygyX9Z4BS+JtlrW3VXFyql7r4copov9R+nc+r3Nnf6PiKouoQ3GnzE/lX4O9lA5 qtqgL9RKeZTtgw8gRuuv/SFUIU5CglX+vJdOpIkh3XPo2fAv6370VZMHInrLYfgtq0VgKP8mbn98U BGM12OyvkgjC+U3Uz3Ql1bFFylM+W9CTN4fhip9qJ9LDDtx5Zwk0+/CZBJZu4TvAonJOfFmJNBQQj fG7eq9hrelFEh0pr9otbFYrrr622HUWFXIFB1E0lSVCG7DB/Ig2g5G/VZ49wcOXg1BS2R65TowNqr LeKXy8DQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nRFjB-000kY3-Ou; Mon, 07 Mar 2022 15:56:53 +0000 Date: Mon, 7 Mar 2022 07:56:53 -0800 From: Christoph Hellwig To: Jarkko Sakkinen Cc: Christoph Hellwig , Matthew Wilcox , 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 , G@iki.fi, Maarten Lankhorst , Greg Kroah-Hartman , Tvrtko Ursulin , Vasily Averin , Shakeel Butt , Michal Hocko , zhangyiru , Alexey Gladkov , Alexander Mikhalitsyn , 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 0/3] MAP_POPULATE for device memory Message-ID: References: <20220306053211.135762-1-jarkko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: BCA4940007 X-Rspam-User: Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=wW7FyJ7w; dmarc=none; spf=none (imf17.hostedemail.com: domain of BATV+2f3b7bc2299b721f5e4c+6770+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+2f3b7bc2299b721f5e4c+6770+infradead.org+hch@bombadil.srs.infradead.org X-Stat-Signature: n7ak1ronmrq9ip8ugsd6in6mitkkwmk9 X-HE-Tag: 1646668623-187786 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000008, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Mar 07, 2022 at 03:29:35PM +0200, Jarkko Sakkinen wrote: > So what would you suggest to sort out the issue? I'm happy to go with > ioctl if nothing else is acceptable. PLenty of drivers treat all mmaps as if MAP_POPULATE was specified, typically by using (io_)remap_pfn_range. If there any reason to only optionally have the pre-fault semantics for sgx? If not this should be really simple. And if we have a real need for it to be optional we'll just need to find a sane way to pass that information to ->mmap.