Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754444Ab1ELCNV (ORCPT ); Wed, 11 May 2011 22:13:21 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:60288 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751685Ab1ELCNU (ORCPT ); Wed, 11 May 2011 22:13:20 -0400 MIME-Version: 1.0 In-Reply-To: <4DCA4C05.4030803@redhat.com> References: <4DC7D37F.9040308@redhat.com> <20110509224511.GC15227@parisc-linux.org> <20110510225659.GE9253@agk-dp.fab.redhat.com> <4DCA4C05.4030803@redhat.com> From: Linus Torvalds Date: Wed, 11 May 2011 19:12:57 -0700 Message-ID: Subject: Re: [PATCH] Don't mlock guardpage if the stack is growing up To: Milan Broz Cc: Alasdair G Kergon , Matthew Wilcox , Zdenek Kabelac , Mikulas Patocka , linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, Hugh Dickins , Oleg Nesterov Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 793 Lines: 19 On Wed, May 11, 2011 at 1:42 AM, Milan Broz wrote: > > Another one is cryptsetup [..] Quite frankly, all security-related uses should always be happy about a "MCL_SPARSE" model, since there is no point in ever bringing in pages that haven't been used. The whole (and only) point of mlock[all]() for them is the "avoid to push to disk" issue. I do wonder if we really should ever do the page-in at all. We might simply be better off always just saying "we'll lock pages you've touched, that's it". 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/