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 74392C46467 for ; Mon, 16 Jan 2023 11:35:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EAAE76B0071; Mon, 16 Jan 2023 06:35:23 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E5A8B6B0072; Mon, 16 Jan 2023 06:35:23 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D49796B0073; Mon, 16 Jan 2023 06:35:23 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id C1A106B0071 for ; Mon, 16 Jan 2023 06:35:23 -0500 (EST) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 216E2401D7 for ; Mon, 16 Jan 2023 11:35:23 +0000 (UTC) X-FDA: 80360456526.16.5806EE1 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf10.hostedemail.com (Postfix) with ESMTP id D5A7AC000F for ; Mon, 16 Jan 2023 11:35:20 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=none; spf=pass (imf10.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1673868921; a=rsa-sha256; cv=none; b=TNk3oBdo8fWchgzyh0ZF/bvj2j4oI/lZEEfP8BB4RicpPVDwvk4EjcyjF7RB/6oUQmgJ05 VPwCWV+vfvXupReyGSvQKYcBx5yFa/FcOECDe1TYeIiBtfYr3tey36WXpfN3CCLcmnNsLX TsvqVAzMAJq8JnHqrTkY6/ezQYYe12A= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=none; spf=pass (imf10.hostedemail.com: domain of wangkefeng.wang@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=wangkefeng.wang@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1673868921; 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; bh=Is+T+7xAQmKbYOlWRQOJdODfWbJzdEuFrHJtCUY9oVs=; b=r2/KGJWcSKIKn4dvCK9YMYqzo5SJk5dp5k6Uyi0ukP45HBbF+F/y+ASCRtDYmE7LIo31v+ 9ZIqY6mmz8qmhRSpehfm5QL6P3F0ZgrYVG66HDn47ZZJOQVVGaRIhgmp+Kqpf0ngvI3PvV iwuevrDPVbxYDHeZauDW7mQqOxAAZy0= Received: from dggpemm500001.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NwVJt6q36znVGf; Mon, 16 Jan 2023 19:33:34 +0800 (CST) Received: from [10.174.177.243] (10.174.177.243) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Mon, 16 Jan 2023 19:35:16 +0800 Message-ID: <07774400-8e85-e728-b325-4263ec5499b1@huawei.com> Date: Mon, 16 Jan 2023 19:35:16 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.5.1 Subject: Re: [PATCH -next 5/7] mm: memory: convert wp_page_copy() to use folios Content-Language: en-US To: SeongJae Park , Lorenzo Stoakes CC: David Hildenbrand , Marek Szyprowski , , , , References: <20230113221606.1370-1-sj@kernel.org> From: Kefeng Wang In-Reply-To: <20230113221606.1370-1-sj@kernel.org> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.243] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected X-Rspam-User: X-Rspamd-Queue-Id: D5A7AC000F X-Rspamd-Server: rspam01 X-Stat-Signature: ntq45j78z55ueqfq4fzwct44acipod99 X-HE-Tag: 1673868920-820939 X-HE-Meta: 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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: On 2023/1/14 6:16, SeongJae Park wrote: > Hello, > > On Fri, 13 Jan 2023 19:04:14 +0000 Lorenzo Stoakes wrote: > >> On Fri, Jan 13, 2023 at 02:08:36PM +0100, David Hildenbrand wrote: >>> On 13.01.23 14:01, Marek Szyprowski wrote: >>>> Hi >>>> >>>> On 12.01.2023 09:30, Kefeng Wang wrote: >>>>> The old_page/new_page are converted to old_folio/new_folio in >>>>> wp_page_copy(), then replaced related page functions to folio >>>>> functions. >>>>> >>>>> Signed-off-by: Kefeng Wang >>>> >>>> This patch, merged into today's linux-next as commit 9ebae00c8e30 ("mm: >>>> memory: convert wp_page_copy() to use folios"), causes serious stability >>>> issues on my ARM based test boards. Here is the example of such crash: >>> >>> syzbot is also not happy: >>> >>> https://lkml.kernel.org/r/000000000000807c7805f2205df1@google.com >>> >>> -- >>> Thanks, >>> >>> David / dhildenb >>> >> >> This also completely broke my qemu environment. > > Same to me. > >> >> In that thread Willy points out that the issue stems from blindly assigning >> page_folio(old_page) to old_folio without checking whether it is NULL first, >> therefore triggering a NULL pointer deref. >> >> A quick fix would be to put in a check (as shown below) which fixes the issue, >> but as Willy said, I think we should drop this until it can be fixed in a >> respin. Hello all, sorry for the break, thanks all to quick fix and analysis, as the patch has be dropped from mm-unstable and next, will resend after address some comments from Matthew Wilcox and do more test.