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 C4579C433EF for ; Fri, 15 Jul 2022 02:51:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 147759401C6; Thu, 14 Jul 2022 22:51:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0F7F59401A5; Thu, 14 Jul 2022 22:51:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F280C9401C6; Thu, 14 Jul 2022 22:51:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id E402E9401A5 for ; Thu, 14 Jul 2022 22:51:07 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id B144C20EF8 for ; Fri, 15 Jul 2022 02:51:07 +0000 (UTC) X-FDA: 79687807374.26.2417AD1 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf12.hostedemail.com (Postfix) with ESMTP id B897840085 for ; Fri, 15 Jul 2022 02:51:06 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4LkbQL0QyBzjWy9; Fri, 15 Jul 2022 10:48:26 +0800 (CST) Received: from [10.174.177.76] (10.174.177.76) 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 15.1.2375.24; Fri, 15 Jul 2022 10:50:32 +0800 Subject: Re: [PATCH] mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte To: Peter Xu CC: Axel Rasmussen , Mike Kravetz , Andrew Morton , Muchun Song , Linux MM , LKML References: <20220712130542.18836-1-linmiaohe@huawei.com> <1a27f20c-ed69-398a-5e6d-bb7ec5f14f5f@huawei.com> From: Miaohe Lin Message-ID: Date: Fri, 15 Jul 2022 10:50:32 +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: [10.174.177.76] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657853467; a=rsa-sha256; cv=none; b=BcX6xhHyQ/iGokSe5cD2/8d4yTQV1P3SNZhtouUZ+QuKy/+T/XMs+rmN26H5v1YwMbeAVP pwAjzieO6bAPJxWIYAaUzvDohkKn3FTxYLOLAP+tqwGB8cdK3FFNpcBBJx5FmGpiOZafzQ C7JUvE0NFvaKDPgxjHz6ptUMZTxqVSU= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf12.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657853467; 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=Zjus4UEcBFnWB1lqtJ6JigehRccnp3j1WshCYw/jhJE=; b=UyZMLHZdwzWtsXsSxU4xZ0Ro6Jzda0q7MHXUa5el/Sn0ID1CdMLeJ1/N5ZIM8wJybwf/gY 18FmqfA5JUVuNZSoAr0z49J5y1x2bjxVvyuONKRl/Gd8kwscDz0jWSqsBR/aJPMBUm0ANp E58SBop2i2ZU6pKpyncPuVCNnuItlmw= X-Stat-Signature: q8ghmwettro9ib69yyfzktuhgmhj4adn X-Rspamd-Queue-Id: B897840085 Authentication-Results: imf12.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf12.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1657853466-245749 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 2022/7/14 23:45, Peter Xu wrote: > On Thu, Jul 14, 2022 at 06:09:49PM +0800, Miaohe Lin wrote: >> As discussed in another thread, we might call page_dup_file_rmap for newly >> allocated page (regardless of this patch). So should we come up a seperate >> patch to call page_add_file_rmap here instead? > > Hmm, why we need page_add_file_rmap() even if a new page allocated? Say, > we're at least also using page_dup_file_rmap() in hugetlb_no_page(). > > I see majorly two things extra there: memcg accounts on NR_FILE_MAPPED, and > mlock. But I assume both of them will not apply to hugetlb pages? I think you are right. PageDoubleMap is also irrelevant for hugetlb. page_add_file_rmap shouldn't be called for hugetlb page. It seems page_dup_file_rmap can be regarded as hugetlb variant of page_add_file_rmap. Sorry for making noise. > Thanks.