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 64EE3FA3742 for ; Sat, 29 Oct 2022 01:55:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C23256B0073; Fri, 28 Oct 2022 21:55:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id BD3536B0074; Fri, 28 Oct 2022 21:55:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A9BB96B0075; Fri, 28 Oct 2022 21:55:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 9AF9F6B0073 for ; Fri, 28 Oct 2022 21:55:30 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 737CA140878 for ; Sat, 29 Oct 2022 01:55:30 +0000 (UTC) X-FDA: 80072320020.27.B27457A Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf08.hostedemail.com (Postfix) with ESMTP id 8497E160015 for ; Sat, 29 Oct 2022 01:55:29 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MzjCw6xmTzHvSW; Sat, 29 Oct 2022 09:55:08 +0800 (CST) Received: from [10.174.151.185] (10.174.151.185) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Sat, 29 Oct 2022 09:55:23 +0800 Subject: Re: [PATCH v3 2/2] mm, hwpoison: When copy-on-write hits poison, take page offline To: "Luck, Tony" CC: Matthew Wilcox , Shuai Xue , "Williams, Dan J" , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" , Naoya Horiguchi , Andrew Morton References: <20221019170835.155381-1-tony.luck@intel.com> <20221021200120.175753-1-tony.luck@intel.com> <20221021200120.175753-3-tony.luck@intel.com> From: Miaohe Lin Message-ID: <4de52973-7590-8ba8-62ca-c78e42f36a63@huawei.com> Date: Sat, 29 Oct 2022 09:55:23 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.151.185] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1667008530; 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=MLK/PBT72N2z7ghSUt4AwdTUAnjLbl3xBK2ZS85mV20=; b=oZgZR4pErxyEmTNkqkU9c3ZuEMrLKeZdbbbl/HGuIFYiibGUjyGmxWCb7CSzgChII0oLwK b2kNLNgQV/nXVc7A++EBUCFVT9Mrxh5opt8pp3zAyTVWxfLmlz/CU1YMOIEncCNl9MOmnu JS9W8ZMqupJOInMYslwDDBwHhFWBuEM= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=none; spf=pass (imf08.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1667008530; a=rsa-sha256; cv=none; b=ImA3nnaxA/BoBjQyoCiMnVQtSf95tIMkcKcsqk5ogyI2zkFWsX3GNj5xjBPMDSnQo+rkT+ 4iwmCMKSn8Sqj63NwV7rtWoLHG9WmUcPC/DloYa7aybSE7+diKpszO1DqAU/LKF0SeroGt OlhmZjU1gcOpdP4DyvWX4dJ+lpRQQI8= X-Stat-Signature: 457u79ffghs95bx4octa3h3j3jkuu3aq X-Rspamd-Queue-Id: 8497E160015 X-Rspam-User: Authentication-Results: imf08.hostedemail.com; dkim=none; spf=pass (imf08.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-Rspamd-Server: rspam04 X-HE-Tag: 1667008529-253503 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000009, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2022/10/29 0:13, Luck, Tony wrote: >>> Cannot call memory_failure() directly from the fault handler because >>> mmap_lock (and others) are held. >> >> Could you please explain which lock makes it unfeasible to call memory_failure() directly and >> why? I'm somewhat confused. But I agree using memory_failure_queue() should be a good idea. > > I tried calling memory_failure() directly, and my system just hung. I made the assumption > that it had deadlocked based somewhat on the comments in mm/memory.c about mmap_lock > being held ... but I didn't dig into what had gone wrong. I see. Thanks for your explanation. :) > > -Tony >