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 A3B6CC77B7C for ; Thu, 3 Jul 2025 10:06:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C0F76B0130; Thu, 3 Jul 2025 06:06:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 376EB6B00D3; Thu, 3 Jul 2025 06:06:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 25F0B6B00D3; Thu, 3 Jul 2025 06:06:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 0F5246B012B for ; Thu, 3 Jul 2025 06:06:37 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id CA2DA1A0109 for ; Thu, 3 Jul 2025 10:06:36 +0000 (UTC) X-FDA: 83622523992.15.F9017B6 Received: from fhigh-a4-smtp.messagingengine.com (fhigh-a4-smtp.messagingengine.com [103.168.172.155]) by imf01.hostedemail.com (Postfix) with ESMTP id C3D6E40002 for ; Thu, 3 Jul 2025 10:06:34 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kroah.com header.s=fm2 header.b=bXnSup6a; dkim=pass header.d=messagingengine.com header.s=fm2 header.b=nSUOFKLK; dmarc=pass (policy=none) header.from=kroah.com; spf=pass (imf01.hostedemail.com: domain of greg@kroah.com designates 103.168.172.155 as permitted sender) smtp.mailfrom=greg@kroah.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1751537194; a=rsa-sha256; cv=none; b=Bck4SEZF1FelI77TbByvCsQF39rNL3bLTLpX6uT8Cvdq6B6W7nhW7V4HJu8BUR3ACyJsAd 5cQ8yqTForZ+I2LyZMnKGzw/kddzzXNmTBnO495tlheV2S5W5zxW6tq8G+AJJD3HwCsN1G 9IAos+zu26T9ksFaH6Bn9Z/gUMBQe+U= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=kroah.com header.s=fm2 header.b=bXnSup6a; dkim=pass header.d=messagingengine.com header.s=fm2 header.b=nSUOFKLK; dmarc=pass (policy=none) header.from=kroah.com; spf=pass (imf01.hostedemail.com: domain of greg@kroah.com designates 103.168.172.155 as permitted sender) smtp.mailfrom=greg@kroah.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1751537194; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9lrf5wzMoZ6J/QpHfivU+gednLxgwZTZ/c4/OmLJKLo=; b=3n8fDsBhDfWKpc6rZlv8pvOheUkB/Yay7cLTPxm6H77AxWKGtv4UrWt8S2vUksc/4SAsSy Ao60/SxghJRYptLHmpDIjoRDN5oTLyMd/4kpKoc+XRMW8/LONwJYHj7+/JPkXN/lAwg/Us m8AHSL5uHy4fn3JQaMKVgkzGtvApmIk= Received: from phl-compute-08.internal (phl-compute-08.phl.internal [10.202.2.48]) by mailfhigh.phl.internal (Postfix) with ESMTP id 0F16F14000B9; Thu, 3 Jul 2025 06:06:34 -0400 (EDT) Received: from phl-mailfrontend-01 ([10.202.2.162]) by phl-compute-08.internal (MEProxy); Thu, 03 Jul 2025 06:06:34 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:subject :subject:to:to; s=fm2; t=1751537194; x=1751623594; bh=9lrf5wzMoZ 6J/QpHfivU+gednLxgwZTZ/c4/OmLJKLo=; b=bXnSup6aQieDoOuvAIMgY5JcDz LxThvKxitMaxLgrqGbilntah1YvrSP8RWMVLxvinNO8zo/xo9GZgbTkZv4QzCEdO Jzgu0MDRjTG8L/64LDPBVzZHUjrF9fPPkR6fY9r1LT4xsMObR/T9hwwwoYQpJQ1f 38beKDam6zSnxoAfZsEwdksOnzrLiuDYwvRqH3MLLRyhH1j7Ug3yT36eqD43EZDD Dufax9oXZHRL8nVJPyestwDu4OFenpf0KySOJEzSClZoBCUd3inssJq+U7eYW4TP 5nOCY0Kb7B1B54iwekU7bJz5HbtPx600Awiq5kziy5CJNL7Id4UqwjNxswcw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; t= 1751537194; x=1751623594; bh=9lrf5wzMoZ6J/QpHfivU+gednLxgwZTZ/c4 /OmLJKLo=; b=nSUOFKLKBUBSel8rm8kefj5N/uEAiplic4esh2Ri1yHOt1p2hxF OGvQqL9m+marQ8ly3uW9RExA9B793bwlw7gTAGI3BwKzpvisDZJPyYUrdNtJNR2f fqdB3V2IliQhOlDs87w89cmgbXkONy5LaLheF/g9Kmw1XWcEpqiUl4couezFOYPp 6KqqKZwx/jlvoTdtGlMV5wY9/WO7uq7x55gavQMwhBxOrb3H1YQ17XVMPwSH6qji UXVW1U2BmPeBvx/xLY+pfLSJareJ/TOyTFCiQ71rkVQh/kBJq8mziUnpXErNGJE1 R0LJSezzFG8CyLDNn7HeOb78vhzk6qVucVQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtdefgdduleellecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpuffrtefokffrpgfnqfghnecuuegr ihhlohhuthemuceftddtnecunecujfgurhepfffhvfevuffkfhggtggujgesthdtredttd dtvdenucfhrhhomhepifhrvghgucfmjfcuoehgrhgvgheskhhrohgrhhdrtghomheqnecu ggftrfgrthhtvghrnhepgeehueehgfdtledutdelkeefgeejteegieekheefudeiffdvud effeelvedttddvnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucevlhhushhtvghr ufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtg homhdpnhgspghrtghpthhtohepudegpdhmohguvgepshhmthhpohhuthdprhgtphhtthho pegrhhgrfedutdehuddtsehgmhgrihhlrdgtohhmpdhrtghpthhtohepshhtrggslhgvse hvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtohepuhhrvgiikhhisehgmhgrihhl rdgtohhmpdhrtghpthhtoheprghkphhmsehlihhnuhigqdhfohhunhgurghtihhonhdroh hrghdprhgtphhtthhopegvughumhgriigvthesghhoohhglhgvrdgtohhmpdhrtghpthht oheplhhinhhugidqmhhmsehkvhgrtghkrdhorhhgpdhrtghpthhtoheplhhinhhugidqkh gvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhg X-ME-Proxy: Feedback-ID: i787e41f1:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 3 Jul 2025 06:06:33 -0400 (EDT) Date: Thu, 3 Jul 2025 12:06:32 +0200 From: Greg KH To: Jeongjun Park Cc: stable@vger.kernel.org, urezki@gmail.com, akpm@linux-foundation.org, edumazet@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 6.12.y] mm/vmalloc: fix data race in show_numa_info() Message-ID: <2025070315-breezy-bogged-75f3@gregkh> References: <20250702153428.352047-1-aha310510@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250702153428.352047-1-aha310510@gmail.com> X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: C3D6E40002 X-Stat-Signature: j5pc3cn14objqturoyr9a1fiuo5nrwjb X-Rspam-User: X-HE-Tag: 1751537194-786024 X-HE-Meta: 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 ZECUdkOz cjjCRlOBDum4Nr/GcLZrjue4wf3MdhSmvMS46vaCUT2tT2lzjxZQ0zwt9jBCNICChlW8nPySoHJxrx1N2OS/c3hIm/HEoKVN7NGUpJ5Y09Esny3uUFYucejfVDBlsG7fEP7cmF27toxfoO+fGIRJ7xC8jqrgA2BwZA4GdoWMFhLQx9zXYwX0BZLiIOlvQEsh6lHOjz1YUMlushO5rFlJMRx4n1tzHvt3YWE9wXk+LxjjUrNgdxN6oiPtz3Z7+qjAT5ywo4BQMjBglwoamxccxi6QFDwmamnptAoWAyRxEbqWErnFdPd2hjCQ1wamABQcYmQUSqrhU1aGO+N1Xa6F7HlPmSUV5e28AexMxxRsD0uwr8MA= 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 Thu, Jul 03, 2025 at 12:34:28AM +0900, Jeongjun Park wrote: > commit 5c5f0468d172ddec2e333d738d2a1f85402cf0bc upstream. > > The following data-race was found in show_numa_info(): > > ================================================================== > BUG: KCSAN: data-race in vmalloc_info_show / vmalloc_info_show > > read to 0xffff88800971fe30 of 4 bytes by task 8289 on cpu 0: > show_numa_info mm/vmalloc.c:4936 [inline] > vmalloc_info_show+0x5a8/0x7e0 mm/vmalloc.c:5016 > seq_read_iter+0x373/0xb40 fs/seq_file.c:230 > proc_reg_read_iter+0x11e/0x170 fs/proc/inode.c:299 > .... > > write to 0xffff88800971fe30 of 4 bytes by task 8287 on cpu 1: > show_numa_info mm/vmalloc.c:4934 [inline] > vmalloc_info_show+0x38f/0x7e0 mm/vmalloc.c:5016 > seq_read_iter+0x373/0xb40 fs/seq_file.c:230 > proc_reg_read_iter+0x11e/0x170 fs/proc/inode.c:299 > .... > > value changed: 0x0000008f -> 0x00000000 > ================================================================== > > According to this report,there is a read/write data-race because > m->private is accessible to multiple CPUs. To fix this, instead of > allocating the heap in proc_vmalloc_init() and passing the heap address to > m->private, vmalloc_info_show() should allocate the heap. > > Link: https://lkml.kernel.org/r/20250508165620.15321-1-aha310510@gmail.com > Fixes: 8e1d743 ("mm: vmalloc: support multiple nodes in vmallocinfo") Same comments on the 6.15 version, why change this line? thanks, greg k-h