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 EC0F2C433F5 for ; Thu, 5 May 2022 14:06:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 40D3F6B0071; Thu, 5 May 2022 10:06:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3BB876B0073; Thu, 5 May 2022 10:06:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2A9DD6B0074; Thu, 5 May 2022 10:06:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 1CC446B0071 for ; Thu, 5 May 2022 10:06:41 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id A326C60619 for ; Thu, 5 May 2022 14:06:40 +0000 (UTC) X-FDA: 79431864960.18.54FC15D Received: from mail-pf1-f175.google.com (mail-pf1-f175.google.com [209.85.210.175]) by imf30.hostedemail.com (Postfix) with ESMTP id 304928009E for ; Thu, 5 May 2022 14:06:24 +0000 (UTC) Received: by mail-pf1-f175.google.com with SMTP id i24so3721705pfa.7 for ; Thu, 05 May 2022 07:06:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=Q2ljtViJ97MO8Fx257qphwHt+nQ75TNnUf7PUXRqZ2w=; b=aOqVKnxxHjfkSNNgo6dj5GOX2bAnYy0by0tdOKMfYjFbgycrfiKPTwxwN1MUesuXpd Cd59l4npDzVpoxEUGc/CsE75OtHmFyiOsdCpUnF6ucK+EOQJbIGMNpSbDpnqfdulYYmj CZBBBQ4phmsavwma1uOMH1scQdFF+Qwm1CZDoCgUc1/HXorv7AqJSM0/jrNppluwT62k 6EGnB9xAnfmOid66q/w83ckrkWDRj6yniG2HEtcH5x0A1OwXGRqlv+l5C3zLXzi1e1h1 PlAI9ijpLeAToeMi2imNIX2jliyQicYyNSB88OqqIJvWylKlGB4oBeIlJ71XQrBL+0Tn uRPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Q2ljtViJ97MO8Fx257qphwHt+nQ75TNnUf7PUXRqZ2w=; b=TVykx17sDfzZ8SB7+EUlv2QhARuZTBYeZUDnuM1+NUKYdO9WIQvDCtOuioWqgnSUrP rLNlzqg7Dmqx31r06Wvj5TEc2okXvZlZvBKadWYD8DbWd4xcD1RWYGe1nDq03rWhT8l4 3s5Eo+oB3wTxcyxGNZDn3w4Lyjcsp30YsZIibk8o85eZvNrFZE7d8AeJLYWmhbkANT5u jUaYFpm40nfRwxjcxjC4Ns0qA7Yu8Gpj4q8WsMMQxg6JP9DhHKarOpfxPj+YE89Gziah 2lm3yhFsx5G64yWaL1YBelk8n9EqJAt3aTBi+B/DdfyBRsh+XQB9plK321Yp8jYph+H3 0R1g== X-Gm-Message-State: AOAM533zVoh0MnrnNIevqgPEK2DriQdB+aR1Bit9uR4VLqIRMOHsFUbi RZOofQxCvi801V6HIvHzLwEi1g== X-Google-Smtp-Source: ABdhPJxrGj5lRIZdvSqmPTjoHxM6GE1WuxbKRCnPdk5AEc1NL/F2SsECH09Pl7Da4LnsHVdqpNeUpg== X-Received: by 2002:a05:6a00:248d:b0:510:5d7d:18ab with SMTP id c13-20020a056a00248d00b005105d7d18abmr3713300pfv.51.1651759596369; Thu, 05 May 2022 07:06:36 -0700 (PDT) Received: from localhost ([2408:8207:18da:2310:717f:b863:7c3d:2306]) by smtp.gmail.com with ESMTPSA id m17-20020aa79011000000b0050dc7628177sm1410071pfo.81.2022.05.05.07.06.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 May 2022 07:06:36 -0700 (PDT) Date: Thu, 5 May 2022 22:06:33 +0800 From: Muchun Song To: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Marco Elver , Alexander Potapenko , Dmitry Vyukov , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4] mm/kfence: reset PG_slab and memcg_data before freeing __kfence_pool Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: 5chzdst958t99owo1xjk7mf44tdxfhcx X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 304928009E Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=bytedance-com.20210112.gappssmtp.com header.s=20210112 header.b=aOqVKnxx; spf=pass (imf30.hostedemail.com: domain of songmuchun@bytedance.com designates 209.85.210.175 as permitted sender) smtp.mailfrom=songmuchun@bytedance.com; dmarc=pass (policy=none) header.from=bytedance.com X-Rspam-User: X-HE-Tag: 1651759584-586637 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 Thu, May 05, 2022 at 09:45:18PM +0900, Hyeonggon Yoo wrote: > When kfence fails to initialize kfence pool, it frees the pool. > But it does not reset memcg_data and PG_slab flag. > > Below is a BUG because of this. Let's fix it by resetting memcg_data > and PG_slab flag before free. > > [ 0.089149] BUG: Bad page state in process swapper/0 pfn:3d8e06 > [ 0.089149] page:ffffea46cf638180 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3d8e06 > [ 0.089150] memcg:ffffffff94a475d1 > [ 0.089150] flags: 0x17ffffc0000200(slab|node=0|zone=2|lastcpupid=0x1fffff) > [ 0.089151] raw: 0017ffffc0000200 ffffea46cf638188 ffffea46cf638188 0000000000000000 > [ 0.089152] raw: 0000000000000000 0000000000000000 00000000ffffffff ffffffff94a475d1 > [ 0.089152] page dumped because: page still charged to cgroup > [ 0.089153] Modules linked in: > [ 0.089153] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G B W 5.18.0-rc1+ #965 > [ 0.089154] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 > [ 0.089154] Call Trace: > [ 0.089155] > [ 0.089155] dump_stack_lvl+0x49/0x5f > [ 0.089157] dump_stack+0x10/0x12 > [ 0.089158] bad_page.cold+0x63/0x94 > [ 0.089159] check_free_page_bad+0x66/0x70 > [ 0.089160] __free_pages_ok+0x423/0x530 > [ 0.089161] __free_pages_core+0x8e/0xa0 > [ 0.089162] memblock_free_pages+0x10/0x12 > [ 0.089164] memblock_free_late+0x8f/0xb9 > [ 0.089165] kfence_init+0x68/0x92 > [ 0.089166] start_kernel+0x789/0x992 > [ 0.089167] x86_64_start_reservations+0x24/0x26 > [ 0.089168] x86_64_start_kernel+0xa9/0xaf > [ 0.089170] secondary_startup_64_no_verify+0xd5/0xdb > [ 0.089171] > > Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") > Fixes: 8f0b36497303 ("mm: kfence: fix objcgs vector allocation") > Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> > Thanks for your work on this. Reviewed-by: Muchun Song