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 051EAD637A8 for ; Wed, 13 Nov 2024 18:45:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7E7DF6B008A; Wed, 13 Nov 2024 13:45:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7979F6B008C; Wed, 13 Nov 2024 13:45:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 65F9B6B0095; Wed, 13 Nov 2024 13:45:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 47FCB6B008A for ; Wed, 13 Nov 2024 13:45:32 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id E394D160A5E for ; Wed, 13 Nov 2024 18:45:31 +0000 (UTC) X-FDA: 82781947080.20.9B37F3C Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf08.hostedemail.com (Postfix) with ESMTP id A2549160006 for ; Wed, 13 Nov 2024 18:45:00 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=EWC42zXz; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf08.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1731523352; h=from:from:sender: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:dkim-signature; bh=oiRy7tMpXqzMBxF0V5M1vZe3r1wcdUHw4HgsZMbQH2Q=; b=PgxTgeKKlg8FJEdma7awmvdrg5K50PmlAiKGrHTJokNUTClxyxeiNYn/LiLSt337NI68Eu MXr2aeA0Uyxh1RZK4AA9+mtwH44KzS/w5Fx/SPJBQHNyC/qEVKMoGUnd2COUGk8XjqVSWO AORxIBX9plPZ1tlx/dMkqmeghweuvgA= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=EWC42zXz; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf08.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1731523352; a=rsa-sha256; cv=none; b=hLQXsExMxmdsio5IGah/Tk8I/Ajhd4ZkNS0aRT9z2LLPht5yWr7bA+RoZs3rtmnfdCdgyi nskBSU7hHTukb+1KDT3w9nrap1+hjw2CiUuFhD0B+G6oiIo8sRDhEOHaMqLjVQ1+liPU/c T/g4CMpoVcdMxmE0zHiPcqfJ085R1Fk= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1731523528; 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:autocrypt:autocrypt; bh=oiRy7tMpXqzMBxF0V5M1vZe3r1wcdUHw4HgsZMbQH2Q=; b=EWC42zXziyiPGOdlCU8gnU2IQFiBnm2Es24EQI1aWtqRPFvdQyV+uHlqWdHJb7UOliv0Sp KGqa4tseRE/HsYTIdP0g2YPrsgW5EhmihrzNU+o/QGX7QBM2OzUgvYxrfWjrG8IakzPOUH YYOYbYEGC9K6tjqhm7Z1HMqDbeoabNE= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-264-CNLUanvLMYmqlZeSfTjf9A-1; Wed, 13 Nov 2024 13:45:25 -0500 X-MC-Unique: CNLUanvLMYmqlZeSfTjf9A-1 X-Mimecast-MFC-AGG-ID: CNLUanvLMYmqlZeSfTjf9A Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-43151e4ef43so50140745e9.3 for ; Wed, 13 Nov 2024 10:45:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731523523; x=1732128323; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=oiRy7tMpXqzMBxF0V5M1vZe3r1wcdUHw4HgsZMbQH2Q=; b=B1QfmgLoqf2X8kfLMFIYJO0jBLhU2lUAywlH5gGUt55UEG6VPQCppqqzi8P5belVc1 Kyl8nNP8rBe8yC3GSeHUE1MK8FlXz9jDEL+GUpyCo2bSx4phClHtjTJTGNAM3GzQFc3N E65xuyr/m8l8y+CIRinRXg4LdfZia+4w8ghdiWTWBgNHXmFO1h2NoddxV9/1CsUSW83N hOVn6ALPZywdAgB5cWdAFtKA3wB/Q9hdqla8B6Y5U8A+9v7++dJ60Arf2tfNdj1y8E61 85CVvyClEwlvNSKW5gxny1868eU8Q+jrphOuuN6afqRGEg8qfsPTilpTxKIC886e7iEk woxw== X-Forwarded-Encrypted: i=1; AJvYcCXo5pH3xMj8JGpXL4xk5TwhVkg2seYRUtOJaxVwm25Tks03x7nHiZL3LZenh3rL68AHTDp1L7s04g==@kvack.org X-Gm-Message-State: AOJu0YxFDEsm6CCCw8VkuWWMdlhKdpK9G0kYwdsP2aTmIlny6PAjc9Gj L74iRAjbIK7Cap+lP2cgOmjZt/ZU940yJddAg3HznbGJtDc4g4N0g2OAIQ9fKsLmLjof19UfFxH 9b/5RyXKng+8OHp3atng2z4EbcZ77fZpHk+FABLlLBdQ2TID2 X-Received: by 2002:a05:600c:c08:b0:42c:bd27:4c12 with SMTP id 5b1f17b1804b1-432d4aae6b7mr42155695e9.10.1731523523058; Wed, 13 Nov 2024 10:45:23 -0800 (PST) X-Google-Smtp-Source: AGHT+IEdMZHL+YKk/qd9EVqmBiiyqPXnVJueSChXwtWqIhdBqK0IgMFXLo997Jor7MXgVsm2UQyemg== X-Received: by 2002:a05:600c:c08:b0:42c:bd27:4c12 with SMTP id 5b1f17b1804b1-432d4aae6b7mr42154585e9.10.1731523521172; Wed, 13 Nov 2024 10:45:21 -0800 (PST) Received: from ?IPV6:2003:cb:c708:1500:d584:7ad8:d3f7:5539? (p200300cbc7081500d5847ad8d3f75539.dip0.t-ipconnect.de. [2003:cb:c708:1500:d584:7ad8:d3f7:5539]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-432d54e2e0esm34971275e9.2.2024.11.13.10.45.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 Nov 2024 10:45:20 -0800 (PST) Message-ID: <3ceb9fc6-47cd-4715-ab86-517ed873dc04@redhat.com> Date: Wed, 13 Nov 2024 19:45:19 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 0/7] mm/mprotect: Fix dax puds To: Peter Xu Cc: Jann Horn , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A . Shutemov" , Nicholas Piggin , Matthew Wilcox , Andrew Morton , James Houghton , Huang Ying , "Aneesh Kumar K . V" , Vlastimil Babka , Rick P Edgecombe , Hugh Dickins , Borislav Petkov , Christophe Leroy , Michael Ellerman , Rik van Riel , Dan Williams , Mel Gorman , x86@kernel.org, Ingo Molnar , linuxppc-dev@lists.ozlabs.org, Dave Hansen , Dave Jiang , Oscar Salvador , Thomas Gleixner References: <20240812181225.1360970-1-peterx@redhat.com> <07ba2a86-f22b-43aa-a542-f1a182656b63@redhat.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: TRlcgrAw_gKIKsg0wlKsCA9pF5LRa4BVkKHv34uikd8_1731523523 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: A2549160006 X-Stat-Signature: myxiuy9wxm3mo8d5aeejt4onbxetmh3d X-Rspam-User: X-HE-Tag: 1731523500-465589 X-HE-Meta: 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 s3hOkeI2 z7k0nlZMvXfA3Ir2gq3kzkfVyAPQnTz2aY18yJqs5LWyZN18jcssCQP6GRF3AzLidfIMZ3baYSLxblsN+0WNOP5oNhPYgm2kbYAE4qfWQflNalwVL3bO1TCq/K3staqLPU+Tdoicy2zc33uzFYAif836V1z1hbulh2dutkjmw2vCQgABa/fUNB5JayMbb7ayPowbVmwaqjTIM8oPWK5263oZ2ptqjpdyRMoJK/vHP2m25bnlyjrEayLs3jtnY3NbaS+LmIhyQKDT9TdOzNa4o+yZjifUfFW/a9uL8hv2juho3vDMB7NeuigWtXvvFIGBPyVG8c5dVk1b/scXt86t01CpYV2ysh3SNQeuVcHSO1ONhIqdhj51yM87PgZia3TJllOb59Iob1tjg31CCn+dJx3xdWkALignygX+lY/ZBbpp9Ze3WWKXPf07vRILs4mB0SiEG 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: List-Subscribe: List-Unsubscribe: On 13.11.24 18:56, Peter Xu wrote: > On Wed, Nov 13, 2024 at 05:42:15PM +0100, David Hildenbrand wrote: >> On 13.11.24 17:39, Peter Xu wrote: >>> On Mon, Nov 11, 2024 at 10:20:59PM +0100, Jann Horn wrote: >>>> On Mon, Aug 12, 2024 at 8:12 PM Peter Xu wrote: >>>>> Dax supports pud pages for a while, but mprotect on puds was missing since >>>>> the start. This series tries to fix that by providing pud handling in >>>>> mprotect(). The goal is to add more types of pud mappings like hugetlb or >>>>> pfnmaps. This series paves way for it by fixing known pud entries. >>>> >>>> Do people actually use hardware where they can use PUD THP mappings >>>> for DAX? I thought that was just some esoteric feature that isn't >>>> actually usable on almost any system. >>>> Was I wrong about that? >>> >>> I did run it with a qemu emulated nvdimm device. Though in reality I've no >>> idea on how many people are using it.. >> >> I wonder if we still have to support it ... or could disable it+rip it out. > > Note that in my previous email, I also mentioned mremap() for PMD on dax > too. If that's a real problem, it won't be fixed even if dropping dax PUD > support. > Very true. > And we definitely want to understand whether there're still users on pud > dax to consider dropping anything.. it could still be that both mprotect() > and mremap() are not yet used in the current use cases. Right, but at least NVDIMMs are getting less important. Just a thought if this is really still worth having. -- Cheers, David / dhildenb