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(p200300cbc708de00549ee4e498dfff72.dip0.t-ipconnect.de. [2003:cb:c708:de00:549e:e4e4:98df:ff72]) by smtp.gmail.com with ESMTPSA id v188-20020a1cacc5000000b00384b71a50d5sm1507806wme.24.2022.03.22.02.46.38 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Mar 2022 02:46:40 -0700 (PDT) Message-ID: <10851f31-632c-5fb4-a941-3dccc46e5156@redhat.com> Date: Tue, 22 Mar 2022 10:46:38 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.2 Subject: Re: [PATCH v1 4/7] arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Content-Language: en-US To: Catalin Marinas , Will Deacon Cc: linux-kernel@vger.kernel.org, Andrew Morton , Hugh Dickins , Linus Torvalds , David Rientjes , Shakeel Butt , John Hubbard , Jason Gunthorpe , Mike Kravetz , Mike Rapoport , Yang Shi , "Kirill A . Shutemov" , Matthew Wilcox , Vlastimil Babka , Jann Horn , Michal Hocko , Nadav Amit , Rik van Riel , Roman Gushchin , Andrea Arcangeli , Peter Xu , Donald Dutile , Christoph Hellwig , Oleg Nesterov , Jan Kara , Liang Zhang , Pedro Gomes , Oded Gabbay , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , linux-mm@kvack.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org References: <20220315141837.137118-1-david@redhat.com> <20220315141837.137118-5-david@redhat.com> <20220321143802.GC11145@willie-the-truck> <20220321174404.GA11389@willie-the-truck> From: David Hildenbrand Organization: Red Hat In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21.03.22 19:27, Catalin Marinas wrote: > On Mon, Mar 21, 2022 at 05:44:05PM +0000, Will Deacon wrote: >> On Mon, Mar 21, 2022 at 04:07:48PM +0100, David Hildenbrand wrote: >>> So the example you gave cannot possibly have that bit set. From what I >>> understand, it should be fine. But I have no real preference: I can also >>> just stick to the original patch, whatever you prefer. >> >> I think I'd prefer to stay on the safe side and stick with bit 2 as you >> originally proposed. If we need to support crazy numbers of swapfiles >> in future then we can revisit the idea of allocating bit 1. > > Sounds fine to me. David, feel free to keep my reviewed-by on the > original patch. > Thanks both, I'll add the following comment to the patch: "Note that we might be able to reuse bit 1, but reusing bit 1 turned out problematic in the past for PROT_NONE handling; so let's play safe and use another bit." -- Thanks, David / dhildenb 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1FAF5C433EF for ; Tue, 22 Mar 2022 09:47:34 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4KN6912HMkz30J6 for ; Tue, 22 Mar 2022 20:47:33 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; 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[2003:cb:c708:de00:549e:e4e4:98df:ff72]) by smtp.gmail.com with ESMTPSA id v188-20020a1cacc5000000b00384b71a50d5sm1507806wme.24.2022.03.22.02.46.38 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Mar 2022 02:46:40 -0700 (PDT) Message-ID: <10851f31-632c-5fb4-a941-3dccc46e5156@redhat.com> Date: Tue, 22 Mar 2022 10:46:38 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.2 Subject: Re: [PATCH v1 4/7] arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE To: Catalin Marinas , Will Deacon References: <20220315141837.137118-1-david@redhat.com> <20220315141837.137118-5-david@redhat.com> <20220321143802.GC11145@willie-the-truck> <20220321174404.GA11389@willie-the-truck> From: David Hildenbrand Organization: Red Hat In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: x86@kernel.org, Jan Kara , Yang Shi , Dave Hansen , Peter Xu , Michal Hocko , linux-mm@kvack.org, Donald Dutile , Liang Zhang , Borislav Petkov , Alexander Gordeev , Christoph Hellwig , Paul Mackerras , Andrea Arcangeli , linux-s390@vger.kernel.org, Vasily Gorbik , Rik van Riel , Hugh Dickins , Matthew Wilcox , Mike Rapoport , Ingo Molnar , linux-arm-kernel@lists.infradead.org, Jason Gunthorpe , David Rientjes , Pedro Gomes , Jann Horn , John Hubbard , Heiko Carstens , Shakeel Butt , Oleg Nesterov , Thomas Gleixner , Vlastimil Babka , Oded Gabbay , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Nadav Amit , Andrew Morton , Linus Torvalds , Roman Gushchin , "Kirill A . Shutemov" , Mike Kravetz Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 21.03.22 19:27, Catalin Marinas wrote: > On Mon, Mar 21, 2022 at 05:44:05PM +0000, Will Deacon wrote: >> On Mon, Mar 21, 2022 at 04:07:48PM +0100, David Hildenbrand wrote: >>> So the example you gave cannot possibly have that bit set. From what I >>> understand, it should be fine. But I have no real preference: I can also >>> just stick to the original patch, whatever you prefer. >> >> I think I'd prefer to stay on the safe side and stick with bit 2 as you >> originally proposed. If we need to support crazy numbers of swapfiles >> in future then we can revisit the idea of allocating bit 1. > > Sounds fine to me. David, feel free to keep my reviewed-by on the > original patch. > Thanks both, I'll add the following comment to the patch: "Note that we might be able to reuse bit 1, but reusing bit 1 turned out problematic in the past for PROT_NONE handling; so let's play safe and use another bit." -- Thanks, David / dhildenb 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1CA8AC433EF for ; Tue, 22 Mar 2022 09:48:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jZ9Uj1m0JHcdh61AXGRBZ8PSU+ybpYEmQk+6Pq5mlPo=; b=FuPjE034u21z/b qyWAITwHTSp+EtT/RtI7yDrNhe7zTz42QPPRw076OLgJKTvrsNsfjrDghEgyVosAc9dOZsS2nGlt3 r2jZVyJ/A9N5rI4extdWE2xtfJTccMUPLT3neocS1zvrxSJ493VhEAa505zOwosy0JtzuybmymB5j lZY43jziiwMmWNGpiJMtWqvoqDYX/gn2+eWwLfNS9KJvK1M9nKnWK8pbWVadKCPa5xlNGdfEGDKfv 1n+riRHBf6lNj2yFHgEcCWxsUipeZK8B/vm/1KUa9sNmuM0cJi9Zkvf26FApF+ZTdqxL2io/I69Xk Xi3KYr8BMDbWz7qwAV6g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nWb6G-00Adts-Uy; Tue, 22 Mar 2022 09:46:49 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nWb6D-00Adso-7Y for linux-arm-kernel@lists.infradead.org; Tue, 22 Mar 2022 09:46:46 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1647942403; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gj16fIvhMGn60A3rgtQAZDpb6AlAuaEkvfPmTyLtwTQ=; b=R1ySavt5osXkTuXusBrsfDurTnhoXlt4uT+0GKNuUGJ9iJQFVKW/D27bmhvoaTOpLsl2Yx wBHyAg6ZDceUl/QJdDququxS7RLzqQ6FCECBehsK/W3QrRLVFgXPqPtVnoACMgSmC1N1lZ Yo7NqyIgJ8waF0F97F/ATgW2CLj2t1w= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-36-aQqe9eyoPMWeUeccqTQaGg-1; Tue, 22 Mar 2022 05:46:42 -0400 X-MC-Unique: aQqe9eyoPMWeUeccqTQaGg-1 Received: by mail-wm1-f71.google.com with SMTP id z16-20020a05600c0a1000b0038bebbd8548so836145wmp.3 for ; Tue, 22 Mar 2022 02:46:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:organization:in-reply-to :content-transfer-encoding; bh=gj16fIvhMGn60A3rgtQAZDpb6AlAuaEkvfPmTyLtwTQ=; b=vZxlvefMGFQ5wmugZMKoX5dl7682QPuIubXHDoGkHjqHYzPGitDsoeoq3F5MJmqxJr ByNyv8UdQthEie/06oJceRvUUUXF5+wf2exBTq4FVbwA4srUkGX2F9Lo0c+Iv15V/KaP Z0NhmMwFD+smhjuH/oHl8rVc8bJqGHmv9mFIEmFV1bcd3xkHAK6MdGnlb1X+N4UeQCMR qD7mynrocwuZ/fztpRU80MOPrLscs12BsUkqIcEIaGEpeatpZE8a/F0GNiyX39uStyTa 7+LO4U4Iwba2PxquuwkfUZpcuqmgdIVkGzm81BFFCwCZmfcinm2SCoFz7cilAdWK4AVR F3sA== X-Gm-Message-State: AOAM532kwyP3zt+E5d9XpnSzuJFq72HaLd0fmsPGC5smHC0G1RhL9jWa mj+wL2mSo7TKeeUt1YiXbLsC9PT6+oJbw3THA427zO2HwuQ+96ZfCmPJYoB/Z4wmdaYHgmUTRAM GH9wr+azoXsh1r61xGG6t9QL74VeBnwSYL34= X-Received: by 2002:adf:f34e:0:b0:203:fa2f:73e with SMTP id e14-20020adff34e000000b00203fa2f073emr14961300wrp.351.1647942401009; Tue, 22 Mar 2022 02:46:41 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyZd8Uvoix5JtZIw5NnbrgIf9I7tI3M1eMO959R1yIf5jk559l3XNPulFYZR9OqDfvtCDALew== X-Received: by 2002:adf:f34e:0:b0:203:fa2f:73e with SMTP id e14-20020adff34e000000b00203fa2f073emr14961247wrp.351.1647942400705; Tue, 22 Mar 2022 02:46:40 -0700 (PDT) Received: from ?IPV6:2003:cb:c708:de00:549e:e4e4:98df:ff72? (p200300cbc708de00549ee4e498dfff72.dip0.t-ipconnect.de. [2003:cb:c708:de00:549e:e4e4:98df:ff72]) by smtp.gmail.com with ESMTPSA id v188-20020a1cacc5000000b00384b71a50d5sm1507806wme.24.2022.03.22.02.46.38 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Mar 2022 02:46:40 -0700 (PDT) Message-ID: <10851f31-632c-5fb4-a941-3dccc46e5156@redhat.com> Date: Tue, 22 Mar 2022 10:46:38 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.2 Subject: Re: [PATCH v1 4/7] arm64/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE To: Catalin Marinas , Will Deacon Cc: linux-kernel@vger.kernel.org, Andrew Morton , Hugh Dickins , Linus Torvalds , David Rientjes , Shakeel Butt , John Hubbard , Jason Gunthorpe , Mike Kravetz , Mike Rapoport , Yang Shi , "Kirill A . Shutemov" , Matthew Wilcox , Vlastimil Babka , Jann Horn , Michal Hocko , Nadav Amit , Rik van Riel , Roman Gushchin , Andrea Arcangeli , Peter Xu , Donald Dutile , Christoph Hellwig , Oleg Nesterov , Jan Kara , Liang Zhang , Pedro Gomes , Oded Gabbay , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , linux-mm@kvack.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org References: <20220315141837.137118-1-david@redhat.com> <20220315141837.137118-5-david@redhat.com> <20220321143802.GC11145@willie-the-truck> <20220321174404.GA11389@willie-the-truck> From: David Hildenbrand Organization: Red Hat In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220322_024645_377894_30337DA5 X-CRM114-Status: GOOD ( 17.38 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 21.03.22 19:27, Catalin Marinas wrote: > On Mon, Mar 21, 2022 at 05:44:05PM +0000, Will Deacon wrote: >> On Mon, Mar 21, 2022 at 04:07:48PM +0100, David Hildenbrand wrote: >>> So the example you gave cannot possibly have that bit set. From what I >>> understand, it should be fine. But I have no real preference: I can also >>> just stick to the original patch, whatever you prefer. >> >> I think I'd prefer to stay on the safe side and stick with bit 2 as you >> originally proposed. If we need to support crazy numbers of swapfiles >> in future then we can revisit the idea of allocating bit 1. > > Sounds fine to me. David, feel free to keep my reviewed-by on the > original patch. > Thanks both, I'll add the following comment to the patch: "Note that we might be able to reuse bit 1, but reusing bit 1 turned out problematic in the past for PROT_NONE handling; so let's play safe and use another bit." -- Thanks, David / dhildenb _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel