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 X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 076BAC433F5 for ; Thu, 23 Sep 2021 15:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF4F8610D1 for ; Thu, 23 Sep 2021 15:19:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241903AbhIWPVC (ORCPT ); Thu, 23 Sep 2021 11:21:02 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:30945 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233080AbhIWPU7 (ORCPT ); Thu, 23 Sep 2021 11:20:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632410367; h=from:from: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=XGCu5vIJXzqgCg8xHHPR2KnAZqh2TqcPDCJS3P0Px/M=; b=EyiWcpSUPIYHO8ZvlWEgPzwy3llR9Gjkv5714GZP5CYUsFgw6sVOsWJjH6U/+f7Z/MC7sX sgddpm9I3nI6VEfWNDE5m0XaY3aVMEGfAr8dTOECUZPFNzyjV+VXglWRt2Got07Xvupe9S MGjKRsDHg3T9L4jxxZlnkyvq7KEDagA= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-435-U819BazYOcuKRYcYvOg3tA-1; Thu, 23 Sep 2021 11:19:25 -0400 X-MC-Unique: U819BazYOcuKRYcYvOg3tA-1 Received: by mail-wr1-f71.google.com with SMTP id c2-20020adfa302000000b0015e4260febdso5386887wrb.20 for ; Thu, 23 Sep 2021 08:19:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=XGCu5vIJXzqgCg8xHHPR2KnAZqh2TqcPDCJS3P0Px/M=; b=dOtK29dQcKQh0gVuL65gseORhk5zHMRxdWyIeF+bClIlEssmm7nB634DJAoqit6dSR zR9e4N4JCeo4ObDCIBNkyG39Un0Hm7fhzw1M1p1Gdp2lqC15g9io6Mig+Ia3Xizw5q4C yuUr6eauJkCIvnC5NgLlUUO+ptWx41kYvjboABeXf5Osh/Dqmg4esaeljqaCWdXtzm/y 1KG/zqUATJw7qJcpxQNT6lg8Wc2zI6GItV4I7ItIpCsWUbFRdJqMqSocK7HaBCl9U6B6 rDpqIkomjdr9dxlhDd1iYsvtIeY1C3EtQevx6CMz1H1+bDfVhlDW8j6V7ceHWtImAkfm jkrg== X-Gm-Message-State: AOAM530zP4V8bZKPQhQXYM+P8YVBZ3BxvL5xESR7X4RFbA1K5k7DMI9m HjsovDU9IlCFm2J85RbYwlvGHw7W3vMAZ3F1W4S1gA8/GafowXpLkimEka40KEA0Skp84S8Qtxt 1f2axfF3EJJp7B3VCdRLPb+AI X-Received: by 2002:a05:600c:4642:: with SMTP id n2mr16390935wmo.39.1632410364456; Thu, 23 Sep 2021 08:19:24 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwSN9YInxHJH0+b/VUtAFg6XTyNqR/4Wp+Pvtm/ukXlGQBhABku40FhX82R08bdZ8ySOn/iiQ== X-Received: by 2002:a05:600c:4642:: with SMTP id n2mr16390921wmo.39.1632410364252; Thu, 23 Sep 2021 08:19:24 -0700 (PDT) Received: from [192.168.3.132] (p4ff23e5d.dip0.t-ipconnect.de. [79.242.62.93]) by smtp.gmail.com with ESMTPSA id j4sm5899868wrt.67.2021.09.23.08.19.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Sep 2021 08:19:23 -0700 (PDT) Subject: Re: [PATCH] mm/memory_failure: Fix the missing pte_unmap() call To: Qi Zheng , naoya.horiguchi@nec.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, songmuchun@bytedance.com References: <20210923122642.4999-1-zhengqi.arch@bytedance.com> From: David Hildenbrand Organization: Red Hat Message-ID: <7330e2e0-9dc4-e412-a821-ed62a469371d@redhat.com> Date: Thu, 23 Sep 2021 17:19:22 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210923122642.4999-1-zhengqi.arch@bytedance.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 23.09.21 14:26, Qi Zheng wrote: > The paired pte_unmap() call is missing before the > dev_pagemap_mapping_shift() returns. So fix it. > > Signed-off-by: Qi Zheng > --- > mm/memory-failure.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index e2984c123e7e..4e5419f16fd4 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -306,6 +306,7 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, > struct vm_area_struct *vma) > { > unsigned long address = vma_address(page, vma); > + unsigned long ret = 0; > pgd_t *pgd; > p4d_t *p4d; > pud_t *pud; > @@ -330,10 +331,12 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, > return PMD_SHIFT; > pte = pte_offset_map(pmd, address); > if (!pte_present(*pte)) > - return 0; > + goto unmap; > if (pte_devmap(*pte)) > - return PAGE_SHIFT; > - return 0; > + ret = PAGE_SHIFT; > +unmap: > + pte_unmap(pte); > + return ret; > } > > /* > I guess this code never runs on 32bit / highmem, that's why we didn't notice so far. Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb