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 DA931C433EF for ; Thu, 5 May 2022 09:07:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 38D3B6B0071; Thu, 5 May 2022 05:07:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 33B026B0073; Thu, 5 May 2022 05:07:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2034C6B0074; Thu, 5 May 2022 05:07:19 -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 0E4B66B0071 for ; Thu, 5 May 2022 05:07:19 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id D4A362163E for ; Thu, 5 May 2022 09:07:18 +0000 (UTC) X-FDA: 79431110556.11.A0DFFE6 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) by imf08.hostedemail.com (Postfix) with ESMTP id 4878E160022 for ; Thu, 5 May 2022 09:07:07 +0000 (UTC) Received: by mail-pj1-f44.google.com with SMTP id w17-20020a17090a529100b001db302efed6so3549110pjh.4 for ; Thu, 05 May 2022 02:07:17 -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=vzFHg7LpC1f5IJb8pgP21cVA3EcMC1zK7MvlkX40SCk=; b=0YBWTe/JXyCFcM7dhTqyErMW3J9fHg4Anp14lNd9keICEzbNRzMsbp1T8DPiHhbfMv a0bGSiyzndhBZwBq+K0b3Qq7+oRYgL6+f6369FDR9IduzUWXHPXAiXFJMGIyBYbZzMrW V5FvnqJDLHHZO1Q8I5HstF1+xNYXYmqQ8uplY9nsdXwB0nOMo/JfIDoa1ykKZ8Cq2tpO 97SrgRGCW8HcZshF9yuXh41LzIk+0TwKXcYq1DIra3TIHyRct1VT4MCS3DM+xGRnPgmA pAq0Bfb9tU2FCHyWHWASEsX6mJHv1YxTW6YEtdshodnyc2Dehfjo5tf1MuGyDwtD5/oM EX4Q== 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=vzFHg7LpC1f5IJb8pgP21cVA3EcMC1zK7MvlkX40SCk=; b=025PADuDFxI/fvh8BV18ZKh6fV5HOcu4wRs4SjRm17cogUt0CxCWy7eP/GChmmDMB0 7Q4qmUjjbCHk1vAK28Vdx0tZa60EGuQnnmNlWIF+ATg2C2YDNB7w+fEJjyYMJC8wMan/ UGlwIE2mqlFBz0O920ZGlbcw3desKYpvXnz//Avue/a/FaMQY88sBofPqO1nd/zev0Jq HANA98UB6n7gSoLsfCqlKcBgTlSDZ57SST3161giUXej34wMyFLqWDuFYQgoPCWPfPnB 9uj5E3V7Y0FrDH/aWnpN7hPIWulvXz4UE06TM1Wf2tYYcAbZZlStTUKHCpLPev82aVzf F5ag== X-Gm-Message-State: AOAM531svSWADzOvBQBqrFU04IBGNwTedIp48HHxxWheXkLgeMoiSRYa hN9OyH6c9aIbK2vVqHJejlNZLQ== X-Google-Smtp-Source: ABdhPJxPyTqYYsJ3ZFTfoesmL2tSuqns/ua0YMiyZo59qZCgtFrdEHC3JJIqM/k72EfBi6XJJHvaRw== X-Received: by 2002:a17:902:eacd:b0:15c:17fc:31e with SMTP id p13-20020a170902eacd00b0015c17fc031emr26338349pld.4.1651741636318; Thu, 05 May 2022 02:07:16 -0700 (PDT) Received: from localhost ([139.177.225.234]) by smtp.gmail.com with ESMTPSA id 145-20020a630297000000b003c14af505edsm821011pgc.5.2022.05.05.02.07.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 May 2022 02:07:16 -0700 (PDT) Date: Thu, 5 May 2022 17:07:12 +0800 From: Muchun Song To: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Alexander Potapenko , Marco Elver , Dmitry Vyukov , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm/kfence: reset PG_slab and memcg_data before freeing __kfence_pool Message-ID: References: <20220505070105.1835745-1-42.hyeyoo@gmail.com> <20220505073920.1880661-1-42.hyeyoo@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220505073920.1880661-1-42.hyeyoo@gmail.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 4878E160022 X-Stat-Signature: gdohrbmpn5d6wwoeg3sjgporkt6tamz5 X-Rspam-User: Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=bytedance-com.20210112.gappssmtp.com header.s=20210112 header.b="0YBWTe/J"; spf=pass (imf08.hostedemail.com: domain of songmuchun@bytedance.com designates 209.85.216.44 as permitted sender) smtp.mailfrom=songmuchun@bytedance.com; dmarc=pass (policy=none) header.from=bytedance.com X-HE-Tag: 1651741627-801861 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 04:39:20PM +0900, Hyeonggon Yoo wrote: > When kfence fails to initialize kfence pool, it frees the pool. > But it does not reset PG_slab flag and memcg_data of struct page. > > Below is a BUG because of this. Let's fix it by resetting PG_slab > and memcg_data 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> > Reviewed-by: Muchun Song Thanks.