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=-4.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8818EC5AE59 for ; Wed, 11 Sep 2019 03:39:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C7AF21D82 for ; Wed, 11 Sep 2019 03:39:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="C2geYC9r" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726648AbfIKDjp (ORCPT ); Tue, 10 Sep 2019 23:39:45 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:46485 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726545AbfIKDjp (ORCPT ); Tue, 10 Sep 2019 23:39:45 -0400 Received: by mail-lj1-f196.google.com with SMTP id e17so18491237ljf.13 for ; Tue, 10 Sep 2019 20:39:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=X6BmCCTqaeiKHBEU2GPvfLm5B6qb+rh7y5TGC07UvGc=; b=C2geYC9rtLL8dmbIZEBWbm3xjz9k6i+yIDHM1XIdxCITtiVxhLCl6R2nZChWyynJEL Ry4edkMKUde/ELMFU6ZbBMZGEmeZCAQgw5GKCdg+wDWPqKe4cH1fp9Qn1zmxHw2z3gZc JYO93qwAObcUrmPQlrK8CQxXWoMPjLZFODuAfXs7uUlf7NTBHeK84hPxtiqkQdU/7Cyp dUnIx6fvJYPNDrrNiOOSF4qpTYT2rM4mgJ3GhQ4N3oGWMPgFN4WcRKCGAypdLt8Xg6JN P00OEqThepdj6oSpht5HP36Wl2e/Xkdu33sDC7wrz47M1LcMdF8qFGw2oZ7iF2hK5EHo KPpA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=X6BmCCTqaeiKHBEU2GPvfLm5B6qb+rh7y5TGC07UvGc=; b=fsBTzcu8vFObnVIXs7o+AqpY8/w7NrxXvCdhNIFXO5Iz2DEG/3/5Ge1m09vuxeOww8 PDCEpWZSjS080JA84+LhpTsTg1vkAsfHtOGGcXG3V2e3JgWjqSBsOVTh7sFOoFUF/eXa 3kxtmcpd03Eg6cAAfuYq8PT/uV2yA7QQwZGhP8l32emN1q0P75ZI84k5eCFuHmIiQG51 uaG3PH3NIDLoh3Ue/XMfB7EGRZgB/I7nDeywk584JfQb6uihFyygvLZwfnUUv2UIJglp YcpXutJbQTF7UNz/B1juQVw9715yJ4+eegG1cuKy9ZOLA18UXBYwuiC2ueTWwmxEET6d vTwQ== X-Gm-Message-State: APjAAAWb3cZguNH8Q8UyG3+cN8p7nzzp/YQj9Sb1Lu8F8oBdthF/BPag uCr9b2tb5RlTtUwsU4d71JRF+NxtwdQqLZ1j61/lwQ== X-Google-Smtp-Source: APXvYqztK0KSkN6OzOo8bybg+rMbotRq/X+CPb2nZ9FGXiJ/z/JEDFNgeXUBAuv5NCnly7PyJ/J3RfL57jZTG7ltO1E= X-Received: by 2002:a2e:9705:: with SMTP id r5mr3781953lji.13.1568173182977; Tue, 10 Sep 2019 20:39:42 -0700 (PDT) MIME-Version: 1.0 References: <7d3d221015cd343df47de4a68ed4776aca2ca0ab.1567649729.git.baolin.wang@linaro.org> <20190910143242.GB3362@kroah.com> In-Reply-To: <20190910143242.GB3362@kroah.com> From: Baolin Wang Date: Wed, 11 Sep 2019 11:39:30 +0800 Message-ID: Subject: Re: [BACKPORT 4.14.y v2 2/6] locking/lockdep: Add debug_locks check in __lock_downgrade() To: Greg KH Cc: "# 3.4.x" , Peter Zijlstra , Ingo Molnar , longman@redhat.com, Arnd Bergmann , Orson Zhai , Vincent Guittot , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Sep 2019 at 22:32, Greg KH wrote: > > On Thu, Sep 05, 2019 at 11:07:14AM +0800, Baolin Wang wrote: > > From: Waiman Long > > > > [Upstream commit 513e1073d52e55b8024b4f238a48de7587c64ccf] > > > > Tetsuo Handa had reported he saw an incorrect "downgrading a read lock" > > warning right after a previous lockdep warning. It is likely that the > > previous warning turned off lock debugging causing the lockdep to have > > inconsistency states leading to the lock downgrade warning. > > > > Fix that by add a check for debug_locks at the beginning of > > __lock_downgrade(). > > > > Reported-by: Tetsuo Handa > > Reported-by: syzbot+53383ae265fb161ef488@syzkaller.appspotmail.com > > Signed-off-by: Waiman Long > > Signed-off-by: Peter Zijlstra (Intel) > > Cc: Andrew Morton > > Cc: Linus Torvalds > > Cc: Paul E. McKenney > > Cc: Peter Zijlstra > > Cc: Thomas Gleixner > > Cc: Will Deacon > > Link: https://lkml.kernel.org/r/1547093005-26085-1-git-send-email-longman@redhat.com > > Signed-off-by: Ingo Molnar > > Signed-off-by: Baolin Wang > > --- > > kernel/locking/lockdep.c | 3 +++ > > 1 file changed, 3 insertions(+) > > Why isn't this relevant for 4.19.y? I can't add a patch to 4.14.y and > then have someone upgrade to 4.19.y and not have the same fix in there, > that would be a regression. > > So can you redo this series also with a 4.19.y set at the same so we > don't get out of sync? I've queued up your first patch already as that > was in 4.19.y (and also needed in 4.9.y). I understood, will do. Thanks. -- Baolin Wang Best Regards