Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758587AbYHDOzY (ORCPT ); Mon, 4 Aug 2008 10:55:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754996AbYHDOyn (ORCPT ); Mon, 4 Aug 2008 10:54:43 -0400 Received: from mx1.redhat.com ([66.187.233.31]:32819 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758140AbYHDOyi (ORCPT ); Mon, 4 Aug 2008 10:54:38 -0400 Date: Mon, 4 Aug 2008 10:53:18 -0400 From: Dave Jones To: Peter Zijlstra Cc: Roland Dreier , Linus Torvalds , David Miller , jeremy@goop.org, hugh@veritas.com, mingo@elte.hu, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH 7/7] lockdep: spin_lock_nest_lock() Message-ID: <20080804145318.GA17867@redhat.com> Mail-Followup-To: Dave Jones , Peter Zijlstra , Roland Dreier , Linus Torvalds , David Miller , jeremy@goop.org, hugh@veritas.com, mingo@elte.hu, akpm@linux-foundation.org, linux-kernel@vger.kernel.org References: <20080804130317.994042639@chello.nl> <20080804131012.246115111@chello.nl> <1217859571.3589.7.camel@twins> <1217860332.3589.11.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1217860332.3589.11.camel@twins> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1120 Lines: 29 On Mon, Aug 04, 2008 at 04:32:12PM +0200, Peter Zijlstra wrote: > On Mon, 2008-08-04 at 07:26 -0700, Roland Dreier wrote: > > > No more than 48 locks (mutexes, rwlocks, spinlock, RCU, everything > > > covered by lockdep) held by any one code-path; including nested > > > interrupt contexts. > > > > Does that mean that something like the new mm_take_all_locks() operation > > is going to explode if someone tries to use it with lockdep on? > > Gah - yes, clearly nobody tried this.. :-/ > > Just looking at the code it will not only run into this limit, but it > would warn about recursion on the second file/anon vma due to utter lack > of annotation. > > Why are people still developing without lockdep? More puzzling, is why hasn't this triggered in the Fedora rawhide kernels, which do have lockdep enabled. Dave -- http://www.codemonkey.org.uk -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/