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=-6.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 4F61DC433E0 for ; Mon, 8 Feb 2021 21:13:52 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D1A9564E56 for ; Mon, 8 Feb 2021 21:13:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D1A9564E56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 353136B0005; Mon, 8 Feb 2021 16:13:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 300A66B006C; Mon, 8 Feb 2021 16:13:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1F0466B006E; Mon, 8 Feb 2021 16:13:51 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0183.hostedemail.com [216.40.44.183]) by kanga.kvack.org (Postfix) with ESMTP id 09FD36B0005 for ; Mon, 8 Feb 2021 16:13:51 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id C2A7D18477160 for ; Mon, 8 Feb 2021 21:13:50 +0000 (UTC) X-FDA: 77796352620.01.slip57_320f48827601 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin01.hostedemail.com (Postfix) with ESMTP id A4943100592E4 for ; Mon, 8 Feb 2021 21:13:50 +0000 (UTC) X-HE-Tag: slip57_320f48827601 X-Filterd-Recvd-Size: 3949 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Mon, 8 Feb 2021 21:13:49 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 2A15364E8F; Mon, 8 Feb 2021 21:13:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612818828; bh=Hsw7u4NisXSHdMbN0miFLrU3qob/BtZRKy5D0WtD4mQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DqkWj9UrgaNlN7tor4WlT/PbjHoDhVkTAWVyRtiehKqBsBIlg2zRzOAntGDW+86wx t9LmuXLRYqrHRZcBc7unC6XAhPNWrMcUUEvHAvwnkCUgMKqMFZnL9bm2GNE5aC4pUI g9uqZwzHwFkcQ+XmsVzR8yYGxPKdKhbTnQ7myE7Mj0cV6qw47j0NdId0MJHEqRslub /el3Boy5sSLWlkjK0Pm94QQLob4G/uLz4vRWnNapLgu2mZBiTSGLPUWdmMesgwLpz4 8w43a6xpBzhX2L15Qekz5VMG+RTL22BH8Ov5Tcl9FLLVyaJGQwK59/7ht8rPcFYKmt XQ6gGB3oh8qzg== Date: Mon, 8 Feb 2021 23:13:26 +0200 From: Mike Rapoport To: David Hildenbrand Cc: Andrew Morton , Alexander Viro , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dan Williams , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mark Rutland , Michal Hocko , Mike Rapoport , Michael Kerrisk , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Rick Edgecombe , Roman Gushchin , Shakeel Butt , Shuah Khan , Thomas Gleixner , Tycho Andersen , Will Deacon , linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-nvdimm@lists.01.org, linux-riscv@lists.infradead.org, x86@kernel.org Subject: Re: [PATCH v17 00/10] mm: introduce memfd_secret system call to create "secret" memory areas Message-ID: <20210208211326.GV242749@kernel.org> References: <20210208084920.2884-1-rppt@kernel.org> <4996348d-5710-d77d-bb14-d84e370b4a5c@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4996348d-5710-d77d-bb14-d84e370b4a5c@redhat.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 08, 2021 at 10:27:18AM +0100, David Hildenbrand wrote: > On 08.02.21 09:49, Mike Rapoport wrote: > > Some questions (and request to document the answers) as we now allow to have > unmovable allocations all over the place and I don't see a single comment > regarding that in the cover letter: > > 1. How will the issue of plenty of unmovable allocations for user space be > tackled in the future? > > 2. How has this issue been documented? E.g., interaction with ZONE_MOVABLE > and CMA, alloc_conig_range()/alloc_contig_pages?. Secretmem sets the mappings gfp mask to GFP_HIGHUSER, so it does not allocate movable pages at the first place. > 3. How are the plans to support migration in the future and which interface > changes will be required? (Michal mentioned some good points to make this > configurable via the interface, we should plan ahead and document) The only interface change required is an addition of bit value for syscall flags, I really think it can be documented with the addition of migration or any other feature for that sake. -- Sincerely yours, Mike.