From patchwork Thu Feb 10 14:17:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12741992 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 18708C433EF for ; Thu, 10 Feb 2022 14:21:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 524536B0082; Thu, 10 Feb 2022 09:21:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 4ADA78D0002; Thu, 10 Feb 2022 09:21:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3742B6B0085; Thu, 10 Feb 2022 09:21:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0129.hostedemail.com [216.40.44.129]) by kanga.kvack.org (Postfix) with ESMTP id 218B16B0082 for ; Thu, 10 Feb 2022 09:21:27 -0500 (EST) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D30D5181AC9C6 for ; Thu, 10 Feb 2022 14:21:26 +0000 (UTC) X-FDA: 79127082972.30.DA596CF Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf01.hostedemail.com (Postfix) with ESMTP id 442C240002 for ; Thu, 10 Feb 2022 14:21:26 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Jvf646DzLzbkBd; Thu, 10 Feb 2022 22:20:12 +0800 (CST) Received: from huawei.com (10.175.124.27) 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 15.1.2308.21; Thu, 10 Feb 2022 22:21:14 +0800 From: Miaohe Lin To: , CC: , , Subject: [PATCH 2/8] mm/memory-failure.c: avoid walking page table when vma_address() return -EFAULT Date: Thu, 10 Feb 2022 22:17:27 +0800 Message-ID: <20220210141733.1908-3-linmiaohe@huawei.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20220210141733.1908-1-linmiaohe@huawei.com> References: <20220210141733.1908-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.124.27] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: 442C240002 Authentication-Results: imf01.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf01.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Stat-Signature: 87qpsiqs8685t7wbqdms89jroosh64m9 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1644502886-173689 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: It's unnecessary to walk the page table when vma_address() return -EFAULT. Return early if so to save some cpu cycles. Signed-off-by: Miaohe Lin Acked-by: Naoya Horiguchi --- mm/memory-failure.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b3ff7e99a421..f86819145ea8 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -315,6 +315,8 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, pmd_t *pmd; pte_t *pte; + if (address == -EFAULT) + return 0; pgd = pgd_offset(vma->vm_mm, address); if (!pgd_present(*pgd)) return 0;