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 578BCC2BD09 for ; Mon, 24 Jun 2024 18:50:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 972D06B0096; Mon, 24 Jun 2024 14:50:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 922B26B009A; Mon, 24 Jun 2024 14:50:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7C2F36B009B; Mon, 24 Jun 2024 14:50:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 5DF906B0096 for ; Mon, 24 Jun 2024 14:50:28 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 01C274127B for ; Mon, 24 Jun 2024 18:50:27 +0000 (UTC) X-FDA: 82266672936.07.797D37E Received: from mail-wm1-f54.google.com (mail-wm1-f54.google.com [209.85.128.54]) by imf19.hostedemail.com (Postfix) with ESMTP id D69401A0011 for ; Mon, 24 Jun 2024 18:50:25 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=Wrwd44rx; spf=pass (imf19.hostedemail.com: domain of usamaarif642@gmail.com designates 209.85.128.54 as permitted sender) smtp.mailfrom=usamaarif642@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719255012; 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=yBiWnUshv9OkKg3tPzc7vkd68oaE09mot+Fd5BTkZ5w=; b=P2PYrA6jZzmavVNVyRLinJCg/d3FTgNzIEzHsQJBHiUax9Rs+rc0BdFvRLeuxY9SieRGq/ Cz1ahJdbFM6iY/2Gj3tAAjDRp0u0s3xjlcuJfHtet+AamBkzlCDPP1R0a4hnM8p7TUUFI+ ZkwC/+BDffEnDjo708EXZeHdas84WIM= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719255012; a=rsa-sha256; cv=none; b=siXRoihOKgq6/QHu2+z1Qwk7eY6ENcASldxEM/zPtFgjsqR3Uy6S+QEkijv6FA3ire5ILa wWSYcYohR8KUyOf0I5itvVceX8o5vCIqlQoVPBhonoIqA+tiMjS+vLHTTZVOQWjslAZwQW e2MmjXV1qf+5u4MmsMB1sEKQlk8aKqM= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=Wrwd44rx; spf=pass (imf19.hostedemail.com: domain of usamaarif642@gmail.com designates 209.85.128.54 as permitted sender) smtp.mailfrom=usamaarif642@gmail.com; dmarc=pass (policy=none) header.from=gmail.com Received: by mail-wm1-f54.google.com with SMTP id 5b1f17b1804b1-421757d217aso51482385e9.3 for ; Mon, 24 Jun 2024 11:50:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1719255024; x=1719859824; darn=kvack.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=yBiWnUshv9OkKg3tPzc7vkd68oaE09mot+Fd5BTkZ5w=; b=Wrwd44rx0W0F76aDwO/bqIj5OtZQ3nlcBPUdeBpeQpoJzWmDppG6qAU1q+ondbI0xi GqGwiJ3R4k+4UTB+l5+LRcJ3VSKyUe2hVgS/2IUs8MsPfmGVeXkoqkwHy2qE2jnD7PLp 7Fs1S38s2ZtWjXiG9tLPJtuEVlcSBeQb+tUt80b7UTmxKHuL8AteGw7xHMTI8t3DUoqU 673x6B3rd2kQurZ2pd50mRuDgR4RsJIEBZCmL3FqOUX9bYYef0cTrPEy/FpVpTrBeYO9 8/TYYPL6jKTHwD77+94euqg8RaMi7NdoJDx+39rtOBlfZYq/h42Xqswls7juk1L2Jgoi VQfA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719255024; x=1719859824; h=content-transfer-encoding:in-reply-to:from:content-language :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=yBiWnUshv9OkKg3tPzc7vkd68oaE09mot+Fd5BTkZ5w=; b=jbSkOxQ994bx0IeyfKUxSJ/2oyy1SB/D2v/CXwpRtGyNGaIlKehuN6Xf6+M2O+E9ds Zp2gPZQfeG8bduZbrMK+Aw0GVDOULmRxXZ9DS+JI7Oai3Vxk7D2csOaBZKn/QgJo6own eZzIohdUkZH8OW6oTbwEwfG8SO3GGBocNxpnAvX+EZ+MPxakGWX4yKmaUd/rOocds1zC 3fQgoXq4XJg+NWfnvOGz+E1YLpI63GHYtyn/punp7vM9JXFyovf8HWNPIBa00SmTTjCz 3a5lLsKQFiAS3GCIwK/o1CmmEq6SRXBvQ+W3tayiYvjzzih5RLEKkdrTZHXQOKJcbZiT K+9Q== X-Forwarded-Encrypted: i=1; AJvYcCWcSKraAwpP0KHqivcp8R/GP3JAa/q1GWwnCbQGwDjuGUwtIBN5B64xdzmfYempapa6xPq3mI0ThBjqkUkEODTJxiE= X-Gm-Message-State: AOJu0Ywlw3BvLKQBuUyvMZMole2JXqUOHdLCCFE/ogpZZFmaKfy9mCEw AU5D/e8y6XdG6mQFz56yQwiTm+LLkohBOumdT4UMtt5y8z5rx1P5 X-Google-Smtp-Source: AGHT+IEG0ohM8vCl8uLGcKYTGbH3rrX+tD6F5+jka/SZNjxategSPRKu6VYzlsUqtGUOqJetdRzptg== X-Received: by 2002:a05:600c:21cc:b0:421:756f:b2e8 with SMTP id 5b1f17b1804b1-4248cc271b9mr48044475e9.11.1719255023980; Mon, 24 Jun 2024 11:50:23 -0700 (PDT) Received: from ?IPV6:2001:16a2:df66:b900:46d:aa3:6645:bcd8? ([2001:16a2:df66:b900:46d:aa3:6645:bcd8]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-366383f65easm10837829f8f.23.2024.06.24.11.50.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 24 Jun 2024 11:50:23 -0700 (PDT) Message-ID: Date: Mon, 24 Jun 2024 21:50:21 +0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [linux-next:master] [mm] 0fa2857d23: WARNING:at_mm/page_alloc.c:#__alloc_pages_noprof To: Matthew Wilcox , Yosry Ahmed Cc: kernel test robot , oe-lkp@lists.linux.dev, lkp@intel.com, Linux Memory Management List , Andrew Morton , Chengming Zhou , Nhat Pham , David Hildenbrand , "Huang, Ying" , Hugh Dickins , Johannes Weiner , Shakeel Butt , Andi Kleen , linux-kernel@vger.kernel.org References: <202406241651.963e3e78-oliver.sang@intel.com> Content-Language: en-US From: Usama Arif In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: D69401A0011 X-Stat-Signature: iuep8cwhs8j7mascezrcots7mtfoynm6 X-HE-Tag: 1719255025-650698 X-HE-Meta: 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 H7KfUjAP 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 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 24/06/2024 21:33, Matthew Wilcox wrote: > On Mon, Jun 24, 2024 at 05:05:56AM -0700, Yosry Ahmed wrote: >> On Mon, Jun 24, 2024 at 1:49 AM kernel test robot wrote: >>> kernel test robot noticed "WARNING:at_mm/page_alloc.c:#__alloc_pages_noprof" on: >>> >>> commit: 0fa2857d23aa170e5e28d13c467b303b0065aad8 ("mm: store zero pages to be swapped out in a bitmap") >>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master >> This is coming from WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp), and >> is triggered by the new bitmap_zalloc() call in the swapon path. For a >> sufficiently large swapfile, bitmap_zalloc() (which uses kmalloc() >> under the hood) cannot be used to allocate the bitmap. > Do we need to use a bitmap? > > We could place a special entry in the swapcache instead (there's > XA_ZERO_ENTRY already defined, and if we need a different entry that's > not XA_ZERO_ENTRY, there's room for a few hundred more special entries). I was going for the most space-efficient and simplest data structure, which is bitmap. I believe xarray is either pointer or integer between 0 and LONG_MAX? We could convert the individual bits into integer and store them, and have another function to extract the integer stored in xarray to a bit, but I think thats basically a separate bitmap_xarray API (which would probably take more space than a traditional bitmap API, and I dont want to make this series dependent on something like that), so I would prefer to use bitmap.