Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964860AbWJCKFy (ORCPT ); Tue, 3 Oct 2006 06:05:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964864AbWJCKFy (ORCPT ); Tue, 3 Oct 2006 06:05:54 -0400 Received: from ns2.suse.de ([195.135.220.15]:29851 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S964862AbWJCKFw (ORCPT ); Tue, 3 Oct 2006 06:05:52 -0400 From: Andi Kleen To: Pavel Machek Subject: Re: How is Code in do_sys_settimeofday() safe in case of SMP and Nest Kernel Path? Date: Tue, 3 Oct 2006 12:03:57 +0200 User-Agent: KMail/1.9.3 Cc: Nick Piggin , Dong Feng , Christoph Lameter , Arjan van de Ven , Paul Mackerras , David Howells , linux-kernel@vger.kernel.org References: <200609301703.45364.ak@suse.de> <20061003080352.GA4078@ucw.cz> In-Reply-To: <20061003080352.GA4078@ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200610031203.57328.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 804 Lines: 21 On Tuesday 03 October 2006 10:03, Pavel Machek wrote: > On Sat 30-09-06 17:03:45, Andi Kleen wrote: > > > > > Did you get to the bottom of this yet? It looks like you're right, > > > and I suggest a seqlock might be a good option. > > > > It basically doesn't matter because nobody changes the time zone after boot. > > Attacker might; in a tight loop, to confuse time-of-day subsystem, or > maybe oops the kernel. (a) only root change it. (b) the time of day subsystem never cares about the time zone. It is just a variable stored for user space. -Andi - 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/