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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 3E7F8C04E87 for ; Wed, 15 May 2019 18:53:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1ABBC20873 for ; Wed, 15 May 2019 18:53:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727154AbfEOSxC (ORCPT ); Wed, 15 May 2019 14:53:02 -0400 Received: from mail-ot1-f68.google.com ([209.85.210.68]:36555 "EHLO mail-ot1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726392AbfEOSxC (ORCPT ); Wed, 15 May 2019 14:53:02 -0400 Received: by mail-ot1-f68.google.com with SMTP id c3so1036655otr.3 for ; Wed, 15 May 2019 11:53:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=F+uKuYKH8D9C30taRndDf2f3BiyObetVuhxljsMhA+w=; b=dTqiLoCH2iQkNJUPDJknBnM3tDtd768jhXToiFyVq4ug5i6Vakk6P0sQk/1fhqy7W4 kX0YLPugcPJcC2Pv8v10vwL1hm+3Ju3gROtHO3i2yI/HMlOW8GXAc4J3ae8ELir4o/Ui RrYh1KWyfn6+NYgfqyUCHK6XxkFl2nKO8w/JqpQXpdpPT5212hUXuZmt/bAkT6MH5dzi NIyWVJlddrSiHpwv6eCX/OVVXZpsAfPduSGCjqweBBKvy2pGI/pyXMnEoPdKM2bYO0Xm cjAaN8mhTuZyN3yoQdVG4Du6zHIHCdC4TTFcINrEvttd+efVT6quenheBcGiJUrwqiZ0 mbSA== X-Gm-Message-State: APjAAAXxAkT9T1zP7yX2/EnBHY3R+oTMFl8bCjLlxnDXWNoJx+JeTfcH 52L8CkaQRZVpp6Ha4s+oJqc= X-Google-Smtp-Source: APXvYqyB1lZtLwM2VdgPfATea+juZlcCsSuhi3KGqNsEZFCafam8pMbRKx9qHz3/tcPn80X+Dfi0tA== X-Received: by 2002:a9d:7643:: with SMTP id o3mr17247096otl.129.1557946381574; Wed, 15 May 2019 11:53:01 -0700 (PDT) Received: from sultan-box.localdomain ([107.193.118.89]) by smtp.gmail.com with ESMTPSA id h23sm1062735oic.10.2019.05.15.11.52.59 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 15 May 2019 11:53:01 -0700 (PDT) Date: Wed, 15 May 2019 11:52:57 -0700 From: Sultan Alsawaf To: Steven Rostedt Cc: Oleg Nesterov , Christian Brauner , Daniel Colascione , Suren Baghdasaryan , Tim Murray , Michal Hocko , Greg Kroah-Hartman , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , 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: <20190515185257.GC2888@sultan-box.localdomain> References: <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> <20190515143248.17b827d0@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190515143248.17b827d0@oasis.local.home> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 15, 2019 at 02:32:48PM -0400, Steven Rostedt wrote: > I'm confused why you did this? Oleg said that debug_locks_off() could've been called and thus prevented lockdep complaints about simple_lmk from appearing. To eliminate any possibility of that, I disabled debug_locks_off(). Oleg also said that __lock_acquire() could return early if lock debugging were somehow turned off after lockdep reported one bug. To mitigate any possibility of that as well, I threw in the BUG_ON() for good measure. I think at this point it's pretty clear that lockdep truly isn't complaining about simple_lmk's locking pattern, and that lockdep's lack of complaints isn't due to it being mysteriously turned off... Sultan