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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,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 B7D4AC433E0 for ; Tue, 2 Feb 2021 14:32:23 +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 4CECB64DDC for ; Tue, 2 Feb 2021 14:32:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4CECB64DDC Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com 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 1FC8E100EA2AF; Tue, 2 Feb 2021 06:32:23 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=195.135.220.15; helo=mx2.suse.de; envelope-from=mhocko@suse.com; receiver= Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (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 1FFA9100EB33A for ; Tue, 2 Feb 2021 06:32:20 -0800 (PST) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612276338; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ZY7R/A8eLGtcqtBTwPz4dc8E6975FZbZj6rab/rk/co=; b=j08LbR+/N4gscwMe9/vv1y6TbSr6g+uI8Fvmd6aUiZN3eXaYwuKCYZD1LwoDENfRkxwGU0 412GY/gqoJEVKSXG9cJ4ADonbDGXxcU99oWydp5Rm3Y/nVMao0u9sPUOYRoKgo3QRhPEJy MTJSdg+5u8XcNBah4K1e9Bay/Y5Jdaw= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7D39BAD78; Tue, 2 Feb 2021 14:32:18 +0000 (UTC) Date: Tue, 2 Feb 2021 15:32:16 +0100 From: Michal Hocko To: David Hildenbrand Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> <6de6b9f9c2d28eecc494e7db6ffbedc262317e11.camel@linux.ibm.com> <20210202124857.GN242749@kernel.org> <6653288a-dd02-f9de-ef6a-e8d567d71d53@redhat.com> <211f0214-1868-a5be-9428-7acfc3b73993@redhat.com>

MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Message-ID-Hash: DFUBS5KQJSIALCZDQKERJ3KOKEMYULRA X-Message-ID-Hash: DFUBS5KQJSIALCZDQKERJ3KOKEMYULRA X-MailFrom: mhocko@suse.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Mike Rapoport , James Bottomley , Andrew Morton , Alexander Viro , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Ingo Molnar , "Kirill A. Shutemov" , Matthew Wilcox , Mark Rutland , Mike Rapoport , Michael Kerrisk , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Rick Edgecombe , Roman Gushchin , Shakeel Butt , Shuah Khan , Thomas Gleixner , Tycho Ander sen , 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, Hagen Paul Pfeifer , Palmer Dabbelt 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 Tue 02-02-21 15:26:20, David Hildenbrand wrote: > On 02.02.21 15:22, Michal Hocko wrote: > > On Tue 02-02-21 15:12:21, David Hildenbrand wrote: > > [...] > > > I think secretmem behaves much more like longterm GUP right now > > > ("unmigratable", "lifetime controlled by user space", "cannot go on > > > CMA/ZONE_MOVABLE"). I'd either want to reasonably well control/limit it or > > > make it behave more like mlocked pages. > > > > I thought I have already asked but I must have forgotten. Is there any > > actual reason why the memory is not movable? Timing attacks? > > I think the reason is simple: no direct map, no copying of memory. This is an implementation detail though and not something terribly hard to add on top later on. I was more worried there would be really fundamental reason why this is not possible. E.g. security implications. -- Michal Hocko SUSE Labs _______________________________________________ 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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 B2A68C433DB for ; Tue, 2 Feb 2021 14:34:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8902664DD6 for ; Tue, 2 Feb 2021 14:34:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234387AbhBBOeV (ORCPT ); Tue, 2 Feb 2021 09:34:21 -0500 Received: from mx2.suse.de ([195.135.220.15]:45390 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234568AbhBBOdF (ORCPT ); Tue, 2 Feb 2021 09:33:05 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612276338; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ZY7R/A8eLGtcqtBTwPz4dc8E6975FZbZj6rab/rk/co=; b=j08LbR+/N4gscwMe9/vv1y6TbSr6g+uI8Fvmd6aUiZN3eXaYwuKCYZD1LwoDENfRkxwGU0 412GY/gqoJEVKSXG9cJ4ADonbDGXxcU99oWydp5Rm3Y/nVMao0u9sPUOYRoKgo3QRhPEJy MTJSdg+5u8XcNBah4K1e9Bay/Y5Jdaw= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7D39BAD78; Tue, 2 Feb 2021 14:32:18 +0000 (UTC) Date: Tue, 2 Feb 2021 15:32:16 +0100 From: Michal Hocko To: David Hildenbrand Cc: Mike Rapoport , James Bottomley , 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 , "Kirill A. Shutemov" , Matthew Wilcox , Mark Rutland , 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, Hagen Paul Pfeifer , Palmer Dabbelt Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> <6de6b9f9c2d28eecc494e7db6ffbedc262317e11.camel@linux.ibm.com> <20210202124857.GN242749@kernel.org> <6653288a-dd02-f9de-ef6a-e8d567d71d53@redhat.com> <211f0214-1868-a5be-9428-7acfc3b73993@redhat.com>

MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 02-02-21 15:26:20, David Hildenbrand wrote: > On 02.02.21 15:22, Michal Hocko wrote: > > On Tue 02-02-21 15:12:21, David Hildenbrand wrote: > > [...] > > > I think secretmem behaves much more like longterm GUP right now > > > ("unmigratable", "lifetime controlled by user space", "cannot go on > > > CMA/ZONE_MOVABLE"). I'd either want to reasonably well control/limit it or > > > make it behave more like mlocked pages. > > > > I thought I have already asked but I must have forgotten. Is there any > > actual reason why the memory is not movable? Timing attacks? > > I think the reason is simple: no direct map, no copying of memory. This is an implementation detail though and not something terribly hard to add on top later on. I was more worried there would be really fundamental reason why this is not possible. E.g. security implications. -- Michal Hocko SUSE Labs 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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 5BA66C43381 for ; Tue, 2 Feb 2021 14:32:35 +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 1B2B664DDC for ; Tue, 2 Feb 2021 14:32:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1B2B664DDC Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com 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=TVo+/CC1ko0d2GPPUinWNscLf32fDPwIMwzIfO5RDSs=; b=qk7hi4xZyr7G1pSrboOOXMW1P ud8rP/YTwKJFtNKAaXuj0kTMD32SUoXqYvxDVW8IHDUE4Ojh3nmnuWdAj0U/eOiWM5SVsAAvZokW5 oo1g3DHCW5v0li8JlzIUKeppGvCmATsQ6hJDgxwBvXiyyFiIfVriWTqiTd/JTZ/tNwOfUiA6txrMw FTt2+L5n+AfsEBWPjyPUYubHILc+B9MRFg1ieC83EVNFfwSSM0uW5o142jLAwJQYgK++KhPfhsudG CHECDsMwLpzz8p0F/GXDYGnMmouv+ibCGbqmGvPQKx/uIy8zPl30E/GuPmBPnJ3X8RlbROEi/nzc/ FRj+eInmA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wjC-0001WW-Vu; Tue, 02 Feb 2021 14:32:27 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wj7-0001Ty-U9; Tue, 02 Feb 2021 14:32:22 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612276338; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ZY7R/A8eLGtcqtBTwPz4dc8E6975FZbZj6rab/rk/co=; b=j08LbR+/N4gscwMe9/vv1y6TbSr6g+uI8Fvmd6aUiZN3eXaYwuKCYZD1LwoDENfRkxwGU0 412GY/gqoJEVKSXG9cJ4ADonbDGXxcU99oWydp5Rm3Y/nVMao0u9sPUOYRoKgo3QRhPEJy MTJSdg+5u8XcNBah4K1e9Bay/Y5Jdaw= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7D39BAD78; Tue, 2 Feb 2021 14:32:18 +0000 (UTC) Date: Tue, 2 Feb 2021 15:32:16 +0100 From: Michal Hocko To: David Hildenbrand Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> <6de6b9f9c2d28eecc494e7db6ffbedc262317e11.camel@linux.ibm.com> <20210202124857.GN242749@kernel.org> <6653288a-dd02-f9de-ef6a-e8d567d71d53@redhat.com> <211f0214-1868-a5be-9428-7acfc3b73993@redhat.com>

MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210202_093222_176401_324C00F0 X-CRM114-Status: GOOD ( 17.70 ) 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 , 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 , Palmer Dabbelt , Arnd Bergmann , James Bottomley , Hagen Paul Pfeifer , 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 , Mike Rapoport 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 Tue 02-02-21 15:26:20, David Hildenbrand wrote: > On 02.02.21 15:22, Michal Hocko wrote: > > On Tue 02-02-21 15:12:21, David Hildenbrand wrote: > > [...] > > > I think secretmem behaves much more like longterm GUP right now > > > ("unmigratable", "lifetime controlled by user space", "cannot go on > > > CMA/ZONE_MOVABLE"). I'd either want to reasonably well control/limit it or > > > make it behave more like mlocked pages. > > > > I thought I have already asked but I must have forgotten. Is there any > > actual reason why the memory is not movable? Timing attacks? > > I think the reason is simple: no direct map, no copying of memory. This is an implementation detail though and not something terribly hard to add on top later on. I was more worried there would be really fundamental reason why this is not possible. E.g. security implications. -- Michal Hocko SUSE Labs _______________________________________________ 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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 C32CAC433DB for ; Tue, 2 Feb 2021 14:33:33 +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 808E964DD6 for ; Tue, 2 Feb 2021 14:33:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 808E964DD6 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com 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=wh1ZuwOqf3ma+MqdrKZ1r/Uy1ed2BmLZhQgo4fktGiQ=; b=uE6ElZ0FPbwbZ+Ye71IPuNGrL gOcNnkfV8T1x8ZHACFB8G8ZUxeUm+Iy+2XrtnFHfb5enNvhzWeaz0FcTkJXknmUmMWUeFta/XhTzm M3pTIAQ3LiOXw6qAqAGUhEvC/hY/9mPwf4bhi0CayYfcyx6Yhi2gdbAI7sDJOViw35diAJ69DaBQo XR8k3x1D3U9HhFMZo0QwussK68dvpEF9idkn7BHW/hBmC12loBiufypCzWIqDEGafKHQ543n1MbUW xjXolibat825KkkVEfjtH6q7YBKMrjou0oPTuj971m1eO+dlg2CfMk8G1fzhLdrQSmMvs6GkXCa0d viXeiI6ww==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wjB-0001W0-5B; Tue, 02 Feb 2021 14:32:25 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l6wj7-0001Ty-U9; Tue, 02 Feb 2021 14:32:22 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612276338; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ZY7R/A8eLGtcqtBTwPz4dc8E6975FZbZj6rab/rk/co=; b=j08LbR+/N4gscwMe9/vv1y6TbSr6g+uI8Fvmd6aUiZN3eXaYwuKCYZD1LwoDENfRkxwGU0 412GY/gqoJEVKSXG9cJ4ADonbDGXxcU99oWydp5Rm3Y/nVMao0u9sPUOYRoKgo3QRhPEJy MTJSdg+5u8XcNBah4K1e9Bay/Y5Jdaw= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 7D39BAD78; Tue, 2 Feb 2021 14:32:18 +0000 (UTC) Date: Tue, 2 Feb 2021 15:32:16 +0100 From: Michal Hocko To: David Hildenbrand Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> <6de6b9f9c2d28eecc494e7db6ffbedc262317e11.camel@linux.ibm.com> <20210202124857.GN242749@kernel.org> <6653288a-dd02-f9de-ef6a-e8d567d71d53@redhat.com> <211f0214-1868-a5be-9428-7acfc3b73993@redhat.com>