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 9C0A8C433DB for ; Mon, 8 Feb 2021 21:15:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6092264E56 for ; Mon, 8 Feb 2021 21:15:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234692AbhBHVPO (ORCPT ); Mon, 8 Feb 2021 16:15:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:33264 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236304AbhBHVOa (ORCPT ); Mon, 8 Feb 2021 16:14:30 -0500 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> Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org 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. 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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 36371C433DB for ; Mon, 8 Feb 2021 21:13:52 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D302664EA4 for ; Mon, 8 Feb 2021 21:13:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D302664EA4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 322A7100EAB63; Mon, 8 Feb 2021 13:13:51 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=rppt@kernel.org; receiver= Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 4DEDB100EAB60 for ; Mon, 8 Feb 2021 13:13:49 -0800 (PST) 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 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-Disposition: inline In-Reply-To: <4996348d-5710-d77d-bb14-d84e370b4a5c@redhat.com> Message-ID-Hash: VIOQO7BICA4UJUDPMPNQBTNZTY5LCH5Y X-Message-ID-Hash: VIOQO7BICA4UJUDPMPNQBTNZTY5LCH5Y X-MailFrom: rppt@kernel.org X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Andrew Morton , Alexander Viro , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , 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 Anders en , 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 X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit 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. _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org 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=-4.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 726E5C433E0 for ; Mon, 8 Feb 2021 21:14:05 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1AAC264E56 for ; Mon, 8 Feb 2021 21:14:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1AAC264E56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=PTrPlIdm8/dq04dHxnO9rJQip819zj30VvMbpyz8CdI=; b=CEjqRw0IIET6rwM16ps2ONkTz c2DyhjJQVAwon6wvbsVZH9umDvgiLXk9SvxOjy/f5xQcSds9Tym60ipOt4IHmqaN3wOLxMF+A2Rkg N+jxPVUDABqpifAMm86xThFIKO6lAHsrgd9qx9t9Ac417BZNowaSm+O8r1EybL0LbflpuCkvTVc0T Bvw9T0gpOEmTH8tTwpN547CuGRZd08WhRgZXQKP/1rqDfP8KpeRfLpr67pL3hYPo341GgP6m99n5q Iu1ZEOWeYbvGtqBWvrP7ijG+79FDZaYHJ1v49w4aNKzGvlGKzOf4ofpClG4U5g3llpTiZG5WdTmRK 7Iy1zpWAg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9Dr2-0008PL-C6; Mon, 08 Feb 2021 21:13:56 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9Dqw-0008NT-3e; Mon, 08 Feb 2021 21:13:51 +0000 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 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-Disposition: inline In-Reply-To: <4996348d-5710-d77d-bb14-d84e370b4a5c@redhat.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210208_161351_098726_2CB58CE7 X-CRM114-Status: GOOD ( 18.09 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Michal Hocko , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, "H. Peter Anvin" , Christopher Lameter , Shuah Khan , Thomas Gleixner , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Michael Kerrisk , Arnd Bergmann , James Bottomley , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Dan Williams , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Shakeel Butt , Andrew Morton , Rick Edgecombe , Roman Gushchin Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org 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. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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=-4.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 04E9EC433E0 for ; Mon, 8 Feb 2021 21:15:08 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5CB3C64E56 for ; Mon, 8 Feb 2021 21:15:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5CB3C64E56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=5aE4CbW2qXJ3IQ7lENfdXAPutCARVLHulw5WOgUsjWY=; b=by+4DSQJaiM3B9uLs6wDaSlLX rVkAZkTI6n78RAfQp7MCTWSAMzBaW3VXLLWcchrKhfLS3cY89hTaO7XiEWnVXz2cgptDnwvU9/ttU dR8VuK+oawyYlMm10HCZu78KBG2rPpa3Rcq3hjd5er+mRJcufPNJH2lFHotOykyrTMWhc6XGzE8qV WKGq0QVEa8F2SbSAe2zd9aAad4GVfx5XsnOvt9okjGqfwVxwmpltEhPLKDKDNKbnd40gCnFR1Q3lw Ng2/+7rx5l5cW8nSjgq0lTl0WnxH5yZ+ee8DDh7QigPl98bh2uL4jKjMxFSb3F0rXpU0Z2Er828Hv nX+H3s0+Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9Dr0-0008Op-3U; Mon, 08 Feb 2021 21:13:54 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9Dqw-0008NT-3e; Mon, 08 Feb 2021 21:13:51 +0000 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 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-Disposition: inline In-Reply-To: <4996348d-5710-d77d-bb14-d84e370b4a5c@redhat.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210208_161351_098726_2CB58CE7 X-CRM114-Status: GOOD ( 18.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Michal Hocko , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, "H. Peter Anvin" , Christopher Lameter , Shuah Khan , Thomas Gleixner , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Michael Kerrisk , Arnd Bergmann , James Bottomley , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Dan Williams , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Shakeel Butt , Andrew Morton , Rick Edgecombe , Roman Gushchin Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel