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=-15.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 8713AC433EF for ; Thu, 23 Sep 2021 15:30:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6BA7E60FDC for ; Thu, 23 Sep 2021 15:30:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241996AbhIWPbi (ORCPT ); Thu, 23 Sep 2021 11:31:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34250 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233085AbhIWPbh (ORCPT ); Thu, 23 Sep 2021 11:31:37 -0400 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5BF51C061574 for ; Thu, 23 Sep 2021 08:30:06 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id r2so6696538pgl.10 for ; Thu, 23 Sep 2021 08:30:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=ZUy1p6PSvt5yN2wZ9JfbzOdoAH6IHdQaxa/WlcclC5A=; b=vBJT9bZ8UIrkJtobhhnlh/mB+9KIPZv0ORskTyPFxmF+FPTxARiT5mBkoOp4F9mJks oV6BXGQb/eIRLo7yw1UkrIb4oA8h6QSYDosiir5tiSGZwJ+1XGFfReDn0ZXK8DbWv0vG uXpJw66fJjk1G80xiF43wKowpDLn/Dnw+1zbv7nSJQaMK6KiO2dFFkW/lAJIkffK5qTN NNdqalKGAv57XsF3w27sPN4uY7kOE3bDk+4bdgW192dqqnKkvA3aTuh8rBj50AFs73i6 5V03TECnDljVWWcxfxdIQCL64+pM8IfCp114L/JzIkqAhlj+9SMt3/kadYYWaQOMqGef 6unQ== 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:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=ZUy1p6PSvt5yN2wZ9JfbzOdoAH6IHdQaxa/WlcclC5A=; b=RPg/kJN3KHvVWlVDrPErlhV6M7QAl9j4fgcmcExNoridjr5WAbSYvj6a+Dy5qAZBl2 56Sy1nmlTKJR9ELSMHwdt+EpmrvFTm3OowcCtaYJrinR6xv2blFxppX1jR3oJCtYLwem wG2RgYSjo+9c3nW1FlDk6gXEoCVTp7h2Dfje6Ozp1lyCdd1izEBEoFBygPgUviEWb0WP c78Z0V0kzxV3PvkQuSGPcvryQid8WwERliuFBspKOsqWDch+F0Gl+EoJca/k3SlRP93+ dEZZFn9zrLkJOzs1S2KWcbdlWSwriCVq6DdBUwnWQ1e1+vguK+n/KoH0eynULJjewiSq g5Uw== X-Gm-Message-State: AOAM532xwgGmScCF2Z1ocQu00aeGg9WPUve5HMZhwQ+lClIDjnUB2CB5 w2zDAKY6H8ymGDjlmQjHZ1BOMlCfp6xckw== X-Google-Smtp-Source: ABdhPJzlRgeEr2IwjeVRqkMvNkcTvR86bvibTMPjWX++/ibNnSHZgn4GAdjqkrTH9WD3WFAmx9RjCg== X-Received: by 2002:a65:6107:: with SMTP id z7mr4762144pgu.43.1632411005784; Thu, 23 Sep 2021 08:30:05 -0700 (PDT) Received: from [10.255.74.217] ([139.177.225.249]) by smtp.gmail.com with ESMTPSA id h10sm9044360pjs.51.2021.09.23.08.30.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Sep 2021 08:30:05 -0700 (PDT) Subject: Re: [PATCH] mm/memory_failure: Fix the missing pte_unmap() call To: David Hildenbrand , 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> <7330e2e0-9dc4-e412-a821-ed62a469371d@redhat.com> From: Qi Zheng Message-ID: <7a93c298-fd78-1963-a9f6-b4a7191bf747@bytedance.com> Date: Thu, 23 Sep 2021 23:30:01 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <7330e2e0-9dc4-e412-a821-ed62a469371d@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/23/21 11:19 PM, David Hildenbrand wrote: > 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. I guess so too. > > Reviewed-by: David Hildenbrand > Thanks, Qi