From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f52.google.com (mail-ed1-f52.google.com [209.85.208.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8BEF72DEA7B; Thu, 28 Aug 2025 07:37:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.52 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756366680; cv=none; b=gvjZHxSC/eIodf4bXPWCDL3HR/rjHRl9VQMg/YWulSEWsRxDh2NPvzV/jktAVWDBsqgyB4Yi6IYfBT13v+fOPiiDeyk9x602vvr6XYoTi0H1WUHtgMfblCTMv0Vx70o9Xm9KGmcndA6O1qvnx57BRhbjTa15M5vhQZuC/OTolDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756366680; c=relaxed/simple; bh=Evx+qHc0PZj/WJzWjKhVcHVcvE7nkS3TygD2JsAVLCE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pnKX7GTeApjwqNIyVHJnSYf8q9NWNqmX/h+aMZyS0PBlXOpplg43Z4frUnKcKdUJ9yvNq3vAQn+h1tKWjZGy43gH9/CQ8JvcS2GPCDNhy8mxNra+wwgf94r2J5ftI48NpNir/iDGAYG+et05bms89nDp39e7Co6FyjPlSepoopU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=TxmgKBFb; arc=none smtp.client-ip=209.85.208.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TxmgKBFb" Received: by mail-ed1-f52.google.com with SMTP id 4fb4d7f45d1cf-61cb9f6dbe7so1131548a12.0; 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=vger.kernel.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=TxmgKBFb3qxDi71Fwfir8qC2NoATnSBLuhH8SWGnYPOeg7duHU2JwIkArwAFRoI3bP 1UabzhGWlZwCf/RsTaKhzAsm4ZFba4pNr9Z8NpDm0GkPzztUadkKblvlAgudTeqWiJ41 TDtInE1meUgFCh7DHbDYz9NmYRD7IFZoQLRAnNV3AQBSAf0XTEdFtX+KOY6wOo8PcmT8 Sjs+i8zwl++amwg5cwK+gJhH23X+AzADqygs33KEDHtQgOnJ/IWfCM9RUuBYMp2iGgru +7QRt2cOgQn35J6JJOfFQiCEWWaEZBU83leSm7E3HB20ChRtWa6Zs4RMywzLDmv1MrUY 2p8Q== 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=It98vGtiP9GToZHqC9/yImB+mjxQpKuYUIKW99JYChP3nTpFKHhM36ctVYBOuszzKc pV9BV26qXcokV8XUWh+roMeObhLjDA+Swv/7/UCF4rDwAnfLQJZ2ds/kRL3UiZJTkJ6x mps2rXVtatIsawknLYS5iwSIkw0YITv17MmYpVY0gMwmR8YDgR+L3AFy0MU7AiaBv6Ud IKYdVNtG0FTUQesusNZNduI4luUqRuBP2Pg0oMLvrzgdTNEtXQVvleoOTIcUjh6K+KLq QSry3OaIJiyHKIle6exZrw57i68+gTzC0bzjVmMbysROqwEFKyVNpbbtSeN+kFDW/4Do vxRQ== X-Forwarded-Encrypted: i=1; AJvYcCUyvRsRjrcz2hzzNGL16dbxDF/oT2ERo6841HlLJYpiAYrazdmYZ9shyMjSsJJa9DFHBUhMDV0EaFj1ow==@vger.kernel.org, AJvYcCVD21Z5jK6QIxbxn7E4J8HcvcaT08u6vAmSN1kn8s2WxlWaFE8lLvOkyR1epAmVjRpKrn9Wh30bz4tJ@vger.kernel.org, AJvYcCVWd4POk1Nhd4qH9aO2VW9gjbiBlVubAygkSaoIs164i+Yz3tycLANwIBONwHVHoDPLDQMGoHDt@vger.kernel.org, AJvYcCVuzN2Ik14gnPBXS5F7HVBoXTDSqhra5WyGlGY9KDJX+d+lyJTL3ny1yp2I2oPzfiAXiIhAbVEbXw==@vger.kernel.org, AJvYcCW6Z/dRm+AhpT2AyGkKtnj+F84m4ksGDZia8xoI+l2caaWQ5LqXbxUp9nkYRp8WoBxfUG+NYTsoeWPotw==@vger.kernel.org, AJvYcCWg2znyOtVyxEyKGdc5CY1SQESXxeorFPDLaCJZyuNVAiz9epnP7bUPjnGQ0A8p4Xr+2YjzQcbqhKwBeQ==@vger.kernel.org, AJvYcCWlsJXmrC83UjiWPdw8oFGhs8eVXDkYmfIRhKmn1WEPTdv9gTqKWuuln8t3JlrfiIPuKWeR5Uk+EAGQacvr@vger.kernel.org, AJvYcCX5XVxqz0RnE8IHUNPnjOTwYZ+miOSvXFQW5MpO/b1DMe8q5f90ZuDVQKudRt8RSEbNETXTWVg4zTUT@vger.kernel.org, AJvYcCXKlgXpl6grbzlDYMbg1JmEqMofGRkyrP7ABPAh1qxAKK4ETL75YBj0Q4V5tklaYTifeAuL5ydes7kw9VPSOa/v@vger.kernel.org, AJvYcCXM7bO9uRd+eOZil5A1s1YzqLeEzcv5wuoME2IQAD5Nkrx/Fw8eX7mGfPFbZ39Mdn7+h6DJ@vger.kernel.org X-Gm-Message-State: AOJu0YwGxUCCkO6POPsL8jIYWDGHpwmVERE0uID6TCgomq8xGfP5GGS8 mv6GnzHSu5iFSgtqP77oFv66pq/nA4WYc+Nf811mmDqKW+ZUnEwdpfp/ X-Gm-Gg: ASbGncurm8o+M71u9hkm0FNIVG92SdhVC4gRveZm8LZv8tj5gtzCAlA0ioiqz0D4f5r rfFYTQHF2e+ICJXQc3r+HHcOGWZJpSBN/NV6WpAQL2yPdLcid9ltZ8pFlRnClyABrhNw5gmAPLN GSNs2+eQW8hGoLen8CSNHjpSkEXki6H4nhb2Ofdn3FqtRDegMukRdcd1GlaIMHnZQqb3U6pTM8w gjnI1owNQCLuUcK0QoXF8qiA/5hr0yZOB/ZE5oT+cYfO0Ys14Z+frSUMtCOrGw8ZooN5qmCVeIN HCQwF3y/EgcJVCJbjtlzJhw4JrTM3GmxAYN4O0ouY/7vhjdBJisRtqvfu7xlegFJHisdsyiJJlN U9DjvITKAvV8gpJkjQNxmsUABoGe7Q4L+xFqnPPmRdn0EXIQ= 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> Reply-To: Wei Yang References: <20250827220141.262669-1-david@redhat.com> <20250827220141.262669-12-david@redhat.com> Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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) 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