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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS 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 92912C04E53 for ; Wed, 15 May 2019 18:32:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6ACB020873 for ; Wed, 15 May 2019 18:32:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727322AbfEOScu (ORCPT ); Wed, 15 May 2019 14:32:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:36396 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726422AbfEOScu (ORCPT ); Wed, 15 May 2019 14:32:50 -0400 Received: from oasis.local.home (50-204-120-225-static.hfc.comcastbusiness.net [50.204.120.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9887720843; Wed, 15 May 2019 18:32:48 +0000 (UTC) Date: Wed, 15 May 2019 14:32:48 -0400 From: Steven Rostedt To: Sultan Alsawaf Cc: Oleg Nesterov , Christian Brauner , Daniel Colascione , Suren Baghdasaryan , Tim Murray , Michal Hocko , Greg Kroah-Hartman , Arve =?UTF-8?B?SGrDuG5uZXbDpWc=?= , Todd Kjos , Martijn Coenen , Ingo Molnar , Peter Zijlstra , LKML , "open list:ANDROID DRIVERS" , linux-mm , kernel-team , Andy Lutomirski , "Serge E. Hallyn" , Kees Cook , Joel Fernandes Subject: Re: [RFC] simple_lmk: Introduce Simple Low Memory Killer for Android Message-ID: <20190515143248.17b827d0@oasis.local.home> In-Reply-To: <20190515172728.GA14047@sultan-box.localdomain> References: <20190319231020.tdcttojlbmx57gke@brauner.io> <20190320015249.GC129907@google.com> <20190507021622.GA27300@sultan-box.localdomain> <20190507153154.GA5750@redhat.com> <20190507163520.GA1131@sultan-box.localdomain> <20190509155646.GB24526@redhat.com> <20190509183353.GA13018@sultan-box.localdomain> <20190510151024.GA21421@redhat.com> <20190513164555.GA30128@sultan-box.localdomain> <20190515145831.GD18892@redhat.com> <20190515172728.GA14047@sultan-box.localdomain> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 15 May 2019 10:27:28 -0700 Sultan Alsawaf wrote: > On Wed, May 15, 2019 at 04:58:32PM +0200, Oleg Nesterov wrote: > > Could you explain in detail what exactly did you do and what do you see in dmesg? > > > > Just in case, lockdep complains only once, print_circular_bug() does debug_locks_off() > > so it it has already reported another false positive __lock_acquire() will simply > > return after that. > > > > Oleg. > > This is what I did: > diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c > index 774ab79d3ec7..009e7d431a88 100644 > --- a/kernel/locking/lockdep.c > +++ b/kernel/locking/lockdep.c > @@ -3078,6 +3078,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, > int class_idx; > u64 chain_key; > > + BUG_ON(!debug_locks || !prove_locking); > if (unlikely(!debug_locks)) > return 0; > > diff --git a/lib/debug_locks.c b/lib/debug_locks.c > index 124fdf238b3d..4003a18420fb 100644 > --- a/lib/debug_locks.c > +++ b/lib/debug_locks.c > @@ -37,6 +37,7 @@ EXPORT_SYMBOL_GPL(debug_locks_silent); > */ > int debug_locks_off(void) > { > + return 0; I'm confused why you did this? -- Steve > if (debug_locks && __debug_locks_off()) { > if (!debug_locks_silent) { > console_verbose(); > >