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 01F7CC02182 for ; Tue, 21 Jan 2025 08:32:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 011446B007B; Tue, 21 Jan 2025 03:32:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id F034E6B0082; Tue, 21 Jan 2025 03:32:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D7DE66B0083; Tue, 21 Jan 2025 03:32:18 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id B69476B007B for ; Tue, 21 Jan 2025 03:32:18 -0500 (EST) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 684E214084E for ; Tue, 21 Jan 2025 08:32:18 +0000 (UTC) X-FDA: 83030791956.11.12FF380 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf28.hostedemail.com (Postfix) with ESMTP id E52EEC0010 for ; Tue, 21 Jan 2025 08:32:15 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Vdtivvnx; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf28.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1737448336; a=rsa-sha256; cv=none; b=UnPUUdLnszo6ExVadiqKEg8DSfx6N5JF+VdYtA3DUZohpXD9fnwsnLBsflxyXflapIxxmU nRS2OFBz2I9OGbLmRM6wfrCP2y1Iic3tFgDWeslTdOgfRN1Ro8FydPlJFAFaLNkwLQI86n ZvEOMSrWcERoxahgmTma/8jKb4X1ZCs= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Vdtivvnx; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf28.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 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=1737448336; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to: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=ZhX0TMO6oLc9mPbqK/qYx3bp1bB6rtTyAOhF5sEnn8A=; b=BkArfWGKlQe+0nSyg0ph9gh0gtlEdsqSl0ka3BxxfQEY9fxh3PRGVgLvKxfhIaXlbmI55C W+NFFtsDk3LBGyLOKHnxQTUIx3k2NHhrNm4xvIOhbm49wuvEwZfynVmaF0Ycl+gmqyX+pn vYw3I3vBthI7m7fhDtFcigfP5snFLsY= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1737448335; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to: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=ZhX0TMO6oLc9mPbqK/qYx3bp1bB6rtTyAOhF5sEnn8A=; b=VdtivvnxTZI1uJ0Jbn056NJMKnBnA3QQMqXZJcN8GQ5oRq2+ZnRSioh67YiFwUFK55FLd6 xROkB2AfXyCs/ngKVGQ+viA7JS9AnvNZ1IbiLhchNL5hABkFAfivKraaccjrmKXwQMwapi CqAd8OUPu4njQ00I26rBDLQM0PRvAhM= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-91-uSxr7vDUPuCY2FNqll_JKw-1; Tue, 21 Jan 2025 03:32:13 -0500 X-MC-Unique: uSxr7vDUPuCY2FNqll_JKw-1 X-Mimecast-MFC-AGG-ID: uSxr7vDUPuCY2FNqll_JKw Received: by mail-wr1-f69.google.com with SMTP id ffacd0b85a97d-385e2579507so2350551f8f.1 for ; Tue, 21 Jan 2025 00:32:13 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737448332; x=1738053132; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ZhX0TMO6oLc9mPbqK/qYx3bp1bB6rtTyAOhF5sEnn8A=; b=wGnzyueGHpWwBTNBzdRjl+rRtdicJBsVFmaO9QKdt9Wp1dJgU4+uzpbEAW7Y8N0+n+ nfZRBO8VNKZO4SyJ1aiB0aD8KjUoYf1lLemAli/5n+0uoiuHOvin0EGzBJ/Uj5cy9inq mJ6ylDPjXjnteo2jHbreCaY+6Ub9g+utmFzkMOAxasbxHgZOP8YJl0aiSfYQRili9dM+ yWv6qzxdzbXFZDheuU13zu0M5Xqko6qgTbv9xH+Msx4X4Eb5UCrsGN/LFVvwwBQM1CVL aR2dtJ991GAqXqOjeb4NPZLvs9xTWuhlnyPf3ZziB8OkYVc0rlKt815Xnm4y7iLfvHp+ 6Ixw== X-Forwarded-Encrypted: i=1; AJvYcCVwvAq6y7Hm7JoJ5SXHlrEridJKVTeLgw/DxOxYOdKTJWEuEeIxZMwGbH+qThXvwPyHSbZS1gzfZA==@kvack.org X-Gm-Message-State: AOJu0YzFWTGhngZAjYLlivv5K0oJ9uvRHnIj/f9wWGscE5LYeD0s9+Ux dAm+TYimJ9ODrk4TAG22JXS7xMGCavmKAiDy9Oe60CPvUZsh6XKeOFLfsZ9zfy38V+kmcgfIU8J wD19hAWvl6R5ENpvoqQEF7Ab25f4DT4MqxKBrjaWk8ijz3+9So11P2aok X-Gm-Gg: ASbGncvgc88bYN+bNB9hweBzl813zfN9oTykmoabi5CZlE96gog9H8rvtZVus03ACk7 8ukDNV3BeDVluMLBLZDwhSd7S8N0y7M7qS0tl0gjQd9R/A0tayZZB52WByLeXv83cTQsG3MZZ7o aYPCVL3weD/9I2n1VvJyEUiDYu42/WVF5f0QN6pEB65gHlZLFddRccJCnYghPGiAIhUENYm6Bh9 t6UOYUN700F5hfo6aIppU3i7J9GhAcg42EBuidkMmwNXwYOl0uqmFf57a09KO2zuWL4tl8cXXcO +yFDUltUUZO/goOfzTe4BohLX9QCAFMWe0pTjoX7y6F+bZuLG9fkKaDK0ixJoIAcKeZoVETXgkE MZbQP6J1t0yXsUvW0UoMijw== X-Received: by 2002:a5d:588e:0:b0:385:faec:d94d with SMTP id ffacd0b85a97d-38bf57bd65bmr16364893f8f.51.1737448332411; Tue, 21 Jan 2025 00:32:12 -0800 (PST) X-Google-Smtp-Source: AGHT+IHgJRGQccKO2gtkWIfhhrA1WRDu2Lo0mPZooAMOQXktKVH3I20Ngbd2wX6e2oGxU1XrzX5/ag== X-Received: by 2002:a5d:588e:0:b0:385:faec:d94d with SMTP id ffacd0b85a97d-38bf57bd65bmr16364861f8f.51.1737448332020; Tue, 21 Jan 2025 00:32:12 -0800 (PST) Received: from ?IPV6:2003:cb:c709:6200:16ba:af70:999d:6a1a? (p200300cbc709620016baaf70999d6a1a.dip0.t-ipconnect.de. [2003:cb:c709:6200:16ba:af70:999d:6a1a]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-38bf3221db2sm12475321f8f.29.2025.01.21.00.32.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 21 Jan 2025 00:32:10 -0800 (PST) Message-ID: <1608b84c-95a3-41c5-93f7-5cf3239fc0b5@redhat.com> Date: Tue, 21 Jan 2025 09:32:09 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Migration/remap question for hugee pages of 2MB To: Mounesh Badiger , linux-mm@kvack.org References: 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: C3vqwRvamXUD9dM5RJ_XfZJwF4oKPgzaI0bfpCWcjHs_1737448332 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: E52EEC0010 X-Rspamd-Server: rspam10 X-Stat-Signature: danr6d7wemrgs7833gqpmjtk9ue7eq8y X-HE-Tag: 1737448335-974834 X-HE-Meta: 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 gb0dQ9+w s7K5PaFSwjwJ4ER2B2tDoU/ydT6gBCZPS2YBh8qrJS0O0W1EtYGvMuHDFL6K00Erlagf/OIWTrTx9BoOFeHY1pH+Xp2whWQ73Sd1iHGOeJ+fD/ougZen2yNK7Sunvq8GkW+VWa/O/YZse9u38QhjowNjprQQn53/XufspFKcDnkZyxbt3++XuUYBk3W7T1quq2kuvDhgXpdHTJ4yl6/OrSY8izfi1BX9wNv66QPQ3wZ8us7x4J+ilqcpjPMf3u8zb6ceouzIynNDVyWfhyfITljXJECnHYjp2znEtWjFiusc/sJCechBuCRvJbzb8VEvcErQ1G3S7nzfJhtIGPvHQX1vgLr9rH6CBdU3LmIN0hrMOTriKfy5Ruk5jkcDcaTtN3hsmwBjh1uWdML0/8DMMVHb1hHhIOTm6s+EnkFyf6CFw7jsbMGb3dg+3B6xLkYPfJuTN 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 21.01.25 09:18, Mounesh Badiger wrote: > Hi, Hi, > Can linux-mm group confirm, if huge pages of size 2MB cannot be migrated > or remapped when user-space uses them for IO with the bypassing kernel? > We need to VA->PA intact once it is mapped. > > We want to reserve huge pages and map them using hugetlbfs into the > userspace.  Use /proc//pagemap  to get VA->PA mapping and use PA > for IO. A kernel that supports CONFIG_MIGRATION will be able to migrate 2 MiB hugetlb folios on most architectures (e.g., x86-64). Such migration might be triggered by CMA allocations or memory offlining. IIRC, ordinary page compaction should not be migrating 2 MB hugetlb folios, because they consume a full pageblock and there is, therefore, no value in trying to compact such pageblocks. So short answer: they can get migrated, but migration might not happen frequently. To block migration, you could long-term pin these pages from getting migrated either using vmsplice() or iouring fixed buffers. (the latter is preferred). -- Cheers, David / dhildenb