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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 76DEACA0FFD for ; Fri, 29 Aug 2025 07:17:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5595D10EB54; Fri, 29 Aug 2025 07:17:02 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="WMgAY7RS"; dkim-atps=neutral Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5B05D10E6CD; Thu, 28 Aug 2025 07:37:58 +0000 (UTC) Received: by mail-ed1-f44.google.com with SMTP id 4fb4d7f45d1cf-61cb9f6dbe7so1131551a12.0; Thu, 28 Aug 2025 00:37:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1756366677; x=1756971477; darn=lists.freedesktop.org; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=TVrt2ctwbXgHbo+Hn2TZ0gCxiv/sLljbJFjbqAY/TQU=; b=WMgAY7RSZ48rQF9CxGJ1qXnOzw6U0P4GaHwBa9+EduNcJallioKhnj4jSIkYTbTwcI l84sZTcQ5Z5uas9ZQzi+j76+0dGuFzWMjBcrkp833NuMHlkNTDdbx1xevTFBI28gakYy QQoN+GaW4NVpZkwZ4BnXO8N9ev4xPg9YQol3088Azw9JUMjp0+k0oxkM6pVOzDvq44ta lTdERaKgWznH0HJKqm9PRYL6wKBBR4qdwozYWsDaBVL9Vi2wNMahUGXeMEKlt93i6uMB TlrTTq2hmL8gvFuGu94VGbibEkSooCVjJkeARQNVNJhZNf+u4x1u+scZsvwMtl4Hvve9 KXBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756366677; x=1756971477; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=TVrt2ctwbXgHbo+Hn2TZ0gCxiv/sLljbJFjbqAY/TQU=; b=ZvYQPFR0zjSk20NnnZ6CywKA8dppTd2UHqClyikd2tLCSvnpIkRh8Wscc5EAEPmR3q aOGJn8ekkUA60z/Qh/Iqlvdsj6WLpbtM6cF3smTUnBBk8J90ERjCKrBqjMbzl+vrJ1uL 54nK/duR5J6+378bBO1uu1vWow7KPegq/My3hs2l7HD5320qPadf+5lAczE1d2b2/wvA ZkIzm79fHTd9170HGVZ2doU98Nad2nBeOAiDDnTOlv3Fhix/mx87SW9mx4djG/XZXYmh 50sqVyYRXz4wrHoWCAu+la3Q+hFKvnkD76P6AaH59NbZ0q0CfhHNfENW+/GXsFOepumY VLww== X-Forwarded-Encrypted: i=1; AJvYcCUj5Q2D9F/em6/a91ksWKVjAuLb4A58VeHSL94D2hL2bvyNrlqt5VeDWu77dIwo7m/XT/FSyiV5iCYj@lists.freedesktop.org, AJvYcCVHSVYDOB/UGki5fisdn2V4FHyAoemiIDH/wH81V03Heutn19c4uJYdij25L2ml19vkYjdBmJubsQo=@lists.freedesktop.org X-Gm-Message-State: AOJu0YzIUE3XZ3TpDy9qrgG9KJcwEA/xFW8W65LV9zyg0omAydHMwrCA Cnue33T7sweJuUkAmzSj6lfwwl00rnErqvL5VCDjp84zbiaidReOJWZ1 X-Gm-Gg: ASbGncve2s19361mDjkRDGMaJ5aYL4STvqGtBd5mUOCnHm5eBStRSLG/n3CZPtMPxpO 9QxZgobxNKaCrljqWaSkHfyEIiMfFqaO/GutA6R9O58eXsNO5m8xNBZZRVO4qxi8QA/M+sHP/MX 34gc+gsHokztxcUcWBOUQl+r2RhKbX+mXnflTezS0y4EjLxgAg2v+zrHxIBwBS3595t6twk0SBJ gm6hZT+t5n+PqUlE+I/eAl2+bOlesQ3IWZVZBV2T6wVbgkcbTJPTMoNqikmeyttv+gLKswDNca9 NCjGiF5qH6OAfHuEXAjoWOk8pHdg94VyVwVC6A1HQOh8RZj61jdzzrRqtdu5Tg/rimyrAk3uuZw 9XQDw/POFjg541N7IOPyVqh03Pm8AFb6G/6SMrzjazdOv03w= X-Google-Smtp-Source: AGHT+IHzpXzU7IRYTRL9u8s1GDWZ3U5CYmUtBakw/pIBZX/rgdseIwaMMauanPlQhlJ9DDnzYy2q2w== X-Received: by 2002:a05:6402:52c4:b0:607:28c9:c3c9 with SMTP id 4fb4d7f45d1cf-61c1b453182mr20154119a12.6.1756366676733; Thu, 28 Aug 2025 00:37:56 -0700 (PDT) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-61cdb00baf9sm715248a12.33.2025.08.28.00.37.56 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 28 Aug 2025 00:37:56 -0700 (PDT) Date: Thu, 28 Aug 2025 07:37:56 +0000 From: Wei Yang To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, Zi Yan , "Mike Rapoport (Microsoft)" , Alexander Potapenko , Andrew Morton , Brendan Jackman , Christoph Lameter , Dennis Zhou , Dmitry Vyukov , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, iommu@lists.linux.dev, io-uring@vger.kernel.org, Jason Gunthorpe , Jens Axboe , Johannes Weiner , John Hubbard , kasan-dev@googlegroups.com, kvm@vger.kernel.org, "Liam R. Howlett" , Linus Torvalds , linux-arm-kernel@axis.com, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-ide@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mips@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, Lorenzo Stoakes , Marco Elver , Marek Szyprowski , Michal Hocko , Muchun Song , netdev@vger.kernel.org, Oscar Salvador , Peter Xu , Robin Murphy , Suren Baghdasaryan , Tejun Heo , virtualization@lists.linux.dev, Vlastimil Babka , wireguard@lists.zx2c4.com, x86@kernel.org Subject: Re: [PATCH v1 11/36] mm: limit folio/compound page sizes in problematic kernel configs Message-ID: <20250828073755.gyq5cyafrxb7lnw2@master> References: <20250827220141.262669-1-david@redhat.com> <20250827220141.262669-12-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250827220141.262669-12-david@redhat.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Mailman-Approved-At: Fri, 29 Aug 2025 07:17:00 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Wei Yang Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Thu, Aug 28, 2025 at 12:01:15AM +0200, David Hildenbrand wrote: >Let's limit the maximum folio size in problematic kernel config where >the memmap is allocated per memory section (SPARSEMEM without >SPARSEMEM_VMEMMAP) to a single memory section. > >Currently, only a single architectures supports ARCH_HAS_GIGANTIC_PAGE >but not SPARSEMEM_VMEMMAP: sh. > >Fortunately, the biggest hugetlb size sh supports is 64 MiB >(HUGETLB_PAGE_SIZE_64MB) and the section size is at least 64 MiB >(SECTION_SIZE_BITS == 26), so their use case is not degraded. > >As folios and memory sections are naturally aligned to their order-2 size >in memory, consequently a single folio can no longer span multiple memory >sections on these problematic kernel configs. > >nth_page() is no longer required when operating within a single compound >page / folio. > >Reviewed-by: Zi Yan >Acked-by: Mike Rapoport (Microsoft) >Signed-off-by: David Hildenbrand Reviewed-by: Wei Yang -- Wei Yang Help you, Help me