From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id 45EE56B7FC1 for ; Fri, 7 Dec 2018 04:22:57 -0500 (EST) Received: by mail-pf1-f197.google.com with SMTP id y88so2822895pfi.9 for ; Fri, 07 Dec 2018 01:22:57 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id 4si2533583pff.161.2018.12.07.01.22.56 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 07 Dec 2018 01:22:56 -0800 (PST) Date: Fri, 7 Dec 2018 10:22:52 +0100 From: Peter Zijlstra Subject: Re: [PATCH v2 08/17] locking/lockdep: Add support for nestable terminal locks Message-ID: <20181207092252.GF2237@hirez.programming.kicks-ass.net> References: <1542653726-5655-1-git-send-email-longman@redhat.com> <1542653726-5655-9-git-send-email-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1542653726-5655-9-git-send-email-longman@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Waiman Long Cc: Ingo Molnar , Will Deacon , Thomas Gleixner , linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Petr Mladek , Sergey Senozhatsky , Andrey Ryabinin , Tejun Heo , Andrew Morton On Mon, Nov 19, 2018 at 01:55:17PM -0500, Waiman Long wrote: > There are use cases where we want to allow nesting of one terminal lock > underneath another terminal-like lock. That new lock type is called > nestable terminal lock which can optionally allow the acquisition of > no more than one regular (non-nestable) terminal lock underneath it. I think I asked for a more coherent changelog on this. The above is still self contradictory and doesn't explain why you'd ever want such a 'misfeature' :-)