From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from LGEAMRELO11.lge.com ([156.147.23.51]:48202 "EHLO lgeamrelo11.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750749AbdLMFi0 (ORCPT ); Wed, 13 Dec 2017 00:38:26 -0500 Subject: Re: [PATCH] locking/lockdep: Add CONFIG_LOCKDEP_AGGRESSIVE To: Linus Torvalds Cc: Theodore Ts'o , Peter Zijlstra , Thomas Gleixner , kernel-team@lge.com, linux-block , linux-fsdevel , Oleg Nesterov , Tejun Heo References: <20171211035017.32678-1-tytso@mit.edu> From: Byungchul Park Message-ID: Date: Wed, 13 Dec 2017 14:38:24 +0900 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org On 12/13/2017 2:00 AM, Linus Torvalds wrote: > On Mon, Dec 11, 2017 at 9:20 PM, Byungchul Park wrote: >> >> The *problem* is false positives, since locks and waiters in >> kernel are not classified properly > > So the problem is that those false positives apparently end up being a > big deal for the filesystem people. > > I personally don't think the code itself has to be removed, but I do > think that it should never have been added on as part of the generic > lock proving, and should always have been a separate config option. I admit it. > I also feel that you dismiss "false positives" much too easily. A I don't dismiss the ones easily... Anyway, I mostly agree with your whole opinion. Thanks for replying. > false positive is a big problem - because it makes people ignore the > real cases (or just disable the functionality entirely). > > It's why I am very quick to disable compiler warnings that have false > positives, for example. Just a couple of "harmless" false positive > warnings will poison the real warnings for people because they'll get > used to seeing warnings while building, and no longer actually look at > them. > > Linus > -- Thanks, Byungchul