Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754181Ab0AHAj6 (ORCPT ); Thu, 7 Jan 2010 19:39:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753931Ab0AHAj5 (ORCPT ); Thu, 7 Jan 2010 19:39:57 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:58557 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753909Ab0AHAj5 (ORCPT ); Thu, 7 Jan 2010 19:39:57 -0500 Date: Thu, 7 Jan 2010 16:39:27 -0800 (PST) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: KAMEZAWA Hiroyuki cc: Peter Zijlstra , Christoph Lameter , Arjan van de Ven , "Paul E. McKenney" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "minchan.kim@gmail.com" , "hugh.dickins" , Nick Piggin , Ingo Molnar Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() In-Reply-To: <20100108092333.1040c799.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <20100104182429.833180340@chello.nl> <20100104182813.753545361@chello.nl> <20100105054536.44bf8002@infradead.org> <20100105192243.1d6b2213@infradead.org> <1262884960.4049.106.camel@laptop> <1262900683.4049.139.camel@laptop> <20100108092333.1040c799.kamezawa.hiroyu@jp.fujitsu.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 851 Lines: 25 On Fri, 8 Jan 2010, KAMEZAWA Hiroyuki wrote: > > Hmm, do_brk() sometimes unmap conflicting mapping. Isn't it be a problem ? No. For two reasons: - sys_brk() doesn't actually do that (see the "find_vma_intersection()" call). I'm not sure why do_brk() does, but it might have to do with execve(). - the patch I sent out just falls back to the old code if it finds something fishy, so it will do whatever do_brk() does regardless. (Yes, brk() does unmap the old brk for the _shrinking_ case, of course. Again, the patch I sent just falls back to the old behavior in that case) Linus -- 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/