Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750754AbWJ0WIW (ORCPT ); Fri, 27 Oct 2006 18:08:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750762AbWJ0WIW (ORCPT ); Fri, 27 Oct 2006 18:08:22 -0400 Received: from mustang.oldcity.dca.net ([216.158.38.3]:53716 "HELO mustang.oldcity.dca.net") by vger.kernel.org with SMTP id S1750754AbWJ0WIW (ORCPT ); Fri, 27 Oct 2006 18:08:22 -0400 Subject: Re: AMD X2 unsynced TSC fix? From: Lee Revell To: Chris Friesen Cc: Andi Kleen , linux-kernel , john stultz In-Reply-To: <45427E91.2000402@nortel.com> References: <1161969308.27225.120.camel@mindpipe> <200610271335.10178.ak@suse.de> <1161981682.27225.184.camel@mindpipe> <45427E91.2000402@nortel.com> Content-Type: text/plain Date: Fri, 27 Oct 2006 18:08:22 -0400 Message-Id: <1161986902.27225.206.camel@mindpipe> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 843 Lines: 24 On Fri, 2006-10-27 at 15:48 -0600, Chris Friesen wrote: > Lee Revell wrote: > > > What exactly does that AMD patch do? > > "...by periodically adjusting the core time-stamp-counters, so that they > are synchronized." > > It sounds like they just periodically write a new value to the TSC. > Presumably they set the "slower" one equal to the "faster" one. > > You'd likely still have windows where time might run backwards, but it > would be better than nothing. The patch also apparently changes boot params to make the OS use the ACPI PM timer, so it must not be a complete solution. Lee - 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/