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 4516CC54E94 for ; Thu, 26 Jan 2023 11:28:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 91CC56B0073; Thu, 26 Jan 2023 06:28:53 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8A4D06B0075; Thu, 26 Jan 2023 06:28:53 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7461E8E0001; Thu, 26 Jan 2023 06:28:53 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 5FF156B0073 for ; Thu, 26 Jan 2023 06:28:53 -0500 (EST) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 263161C62EA for ; Thu, 26 Jan 2023 11:28:53 +0000 (UTC) X-FDA: 80396728146.16.4709DAB Received: from gentwo.de (gentwo.de [161.97.139.209]) by imf09.hostedemail.com (Postfix) with ESMTP id 75DA3140002 for ; Thu, 26 Jan 2023 11:28:51 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=gentwo.de header.s=default header.b="hTW/HzhE"; spf=pass (imf09.hostedemail.com: domain of cl@gentwo.de designates 161.97.139.209 as permitted sender) smtp.mailfrom=cl@gentwo.de; dmarc=pass (policy=none) header.from=gentwo.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1674732531; 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=MjeJA3NTnp7VBIpasqh8v6gjDuTw3unVXYc5oF/te00=; b=b6tHNkbgA+LMaCkvJ8o+Zao9ut+4VWfAeEJGfx9guEdjXbxtd2LosV92yddPlZi9Z/S0Va hv8cSCUnLp5sR/CHMUKNEZBpF+nuVO7Q8gMteAqyIQuzoRvTL/fJbh+qyeD8fO4lHRTtep 3YK4fy5tldMOTPihXtjPCI34bBMPDPU= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=gentwo.de header.s=default header.b="hTW/HzhE"; spf=pass (imf09.hostedemail.com: domain of cl@gentwo.de designates 161.97.139.209 as permitted sender) smtp.mailfrom=cl@gentwo.de; dmarc=pass (policy=none) header.from=gentwo.de ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1674732531; a=rsa-sha256; cv=none; b=7pmuNlbuE5Go676XZ5xOxYBRzU4sF5AhS6X+rr3OX3DRtT8TOKCAqyX9u/EerkoIulnLv4 1YhkV/4xw5dGZBdNvrwu4cYJ84IVCS4JPqOxScIbI40IV6SEPd/lX+uRULJXDgC3vZbMoo wqxKg9kNUYN0oQUr7oTYga69/U596SI= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gentwo.de; s=default; t=1674732529; bh=MjeJA3NTnp7VBIpasqh8v6gjDuTw3unVXYc5oF/te00=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=hTW/HzhEHDw08AypQ8JO9SLQYHba1iZboqg7mongU/LCdGcy0LIkDnwxRwdy88v5U AmZAYk5TgR1OzOJg3RZVHwZkhgctKYX6DXKBJJpJpCANkqDnUIa3xl1Ew61e38Gutx sbJo2/hEv5HKK3xPURdyQ26pqKLpKFJsQvfcw+8o166pz3utFATNO5GSdOxt6bzUMe j4XnwUVjjsnigx1yIiH7xer/waHNiSXAfj3nBHLOTFBpqgPN9DYLyL/M6hdYq1DHch +Y64B9NTk8zLbPf93dc25uqzGQYObUlC8jGWecVfp6f1bh97w2GM43Z8rUoyLvAVLG 0Vh3uLv4I1bCA== Received: by gentwo.de (Postfix, from userid 1001) id 1165AB0028E; Thu, 26 Jan 2023 12:28:49 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by gentwo.de (Postfix) with ESMTP id 0E4FDB00137; Thu, 26 Jan 2023 12:28:49 +0100 (CET) Date: Thu, 26 Jan 2023 12:28:49 +0100 (CET) From: Christoph Lameter To: George Prekas cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Catalin Marinas , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, Thomas Gleixner , "Eric W. Biederman" , Sebastian Andrzej Siewior , Andy Lutomirski , Peter Zijlstra , "Liam R. Howlett" , Fenghua Yu , Andrei Vagin Subject: Re: [PATCH 7/9] mm: kmemleak: erase page->s_mem in slab_destroy In-Reply-To: <20230123170419.7292-8-george@enfabrica.net> Message-ID: <73309bf-ca5b-b0ba-8ac-4be7dcc278b7@gentwo.de> References: <20230123170419.7292-1-george@enfabrica.net> <20230123170419.7292-8-george@enfabrica.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 75DA3140002 X-Stat-Signature: nke7ygatayogsek5uwfa5aqn974nuxbh X-Rspam-User: X-HE-Tag: 1674732531-584791 X-HE-Meta: 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 SG2/ImqY rTdfiwiNabehUM6/wIny+TVWPywNPNYBX2B8qHwP7MCXNhjjtVoLhZNH9aSDN/Uu3QnLGp3pGT13YKoWX3/WDbdtcDzkW1qwBlrWnmDj9tXpY7SvDEfYQ6tMuFZ26QOJrU93Bx7YkZEAe3Yv9ZF1doGIOhloYm5KZTVwAKVGEbtFprCns/xIEgbSO95mMaihIlLC27q5ruJJIXeM+jExo8nH9ZWXak5l2ugNjE/KBb4UTDN1M3hkwaXa/miU794rvXXJBleX/x6zAZhWHOCUIg0zZDQ== 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: On Mon, 23 Jan 2023, George Prekas wrote: > The field s_mem of struct page is initialized with the virtual address > of the page in function alloc_slabmgmt. If kmalloc allocates an object > that starts on this page, then kmemleak knows that this object has 2 > references. On slab_destroy, s_mem should not continue referring to any > allocated object in the future. Nope. s_mem is a pointer to an array of objects. It is not a pointer to a page. If a slab-caches is used for slabmanagement then these objects contain slab metadata which may be a bit confusing.