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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 32F4AC3A5A6 for ; Sat, 31 Aug 2019 01:54:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFFAC23774 for ; Sat, 31 Aug 2019 01:54:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="qo53S/FN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728420AbfHaByz (ORCPT ); Fri, 30 Aug 2019 21:54:55 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:38890 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726640AbfHaByy (ORCPT ); Fri, 30 Aug 2019 21:54:54 -0400 Received: by mail-pg1-f194.google.com with SMTP id e11so4385681pga.5 for ; Fri, 30 Aug 2019 18:54:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=pdFBtfEznPzYI1PZUuaXzJOVce4Il2s8BFPZI5Emkrs=; b=qo53S/FNZr+IQ3+9ohhcRqe1gNSAm0HXkjiVkJFeMf4dbCvyC0ILd7IuD3YC50/SYZ KxZeEzNojwCkoAQyQvwqeo4NcoO5h5mHLabpBAgGNp/hC6E+Uej2NuAATxNTzBtuSjNJ C7Zk7oT7SkfFOOsXSkABL6o56pEwVoF2caYJTQKMdQX99LEnB+ox/91o4LQ05scNzPAA RqeFBqMjtxwXPSvNAW2AvhmyCFP0qX5566MibaxQg4El5ABx8fqo5YGWnQ3FavjDe8v+ r37UWF8vkvFurQacu0r1FZnZa5TRtOOlaT0A+dVsvNbdror8/djmDvVmHs4ja57rHtF8 Mvzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=pdFBtfEznPzYI1PZUuaXzJOVce4Il2s8BFPZI5Emkrs=; b=qojSoBMh0lnZ9xZL9ajor0tH0pxmz4iWp7vlJosmUoCUHCR8qxK0KQFhGXLRRGWYG/ bYyc0AbsAIOtJfQDMrXA0FvzOBPuRCE4rpaomq7LZsVx0GBDQxBobAvdnUhUdWCh9foI PB2IHGdz2IwEmmBxbNRe4x+pt4kcXFR/c9BrCWvnCia1II4vthrxdrSyQgKKUaLAVLxS KFPlPvsPo6RTGqQ+ZNZBvcLsfO2x7/GHlpiJTrcIzF0N8CBFd/h/WpvAxIAz94DaDpo5 UHvc669pQXSf1G23pwxcBfl3E0cx+5bz3wNZ0mh1rPAJYB9+yIE/pfstornuP5Dy/IHq XOsg== X-Gm-Message-State: APjAAAVUKoySHQNYP9LMsaN3cSXg/MVBy1Fhb/Y1yznaCjMGDT5jlD2/ tKDOz9YCh8UxxpFroLxoacKKaQ== X-Google-Smtp-Source: APXvYqw2S4KTFPVmA9LgtP64jK14mKKXmjtAdtsF/lDQXhHqirbJzkENNc8Ufk7eww2P4kgAb4pU/w== X-Received: by 2002:a65:6108:: with SMTP id z8mr15345981pgu.289.1567216493739; Fri, 30 Aug 2019 18:54:53 -0700 (PDT) Received: from [192.168.1.188] (66.29.164.166.static.utbb.net. [66.29.164.166]) by smtp.gmail.com with ESMTPSA id o130sm11871570pfg.171.2019.08.30.18.54.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 30 Aug 2019 18:54:52 -0700 (PDT) Subject: Re: [block/for-next] writeback: don't access page->mapping directly in track_foreign_dirty TP To: Tejun Heo , Jan Kara Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com References: <20190830233954.GC2263813@devbig004.ftw2.facebook.com> From: Jens Axboe Message-ID: Date: Fri, 30 Aug 2019 19:54:51 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190830233954.GC2263813@devbig004.ftw2.facebook.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/30/19 5:39 PM, Tejun Heo wrote: > page->mapping may encode different values in it and page_mapping() > should always be used to access the mapping pointer. > track_foreign_dirty tracepoint was incorrectly accessing page->mapping > directly. Use page_mapping() instead. Also, add NULL checks while at > it. Applied, thanks. -- Jens Axboe