From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750928AbVKJOG4 (ORCPT ); Thu, 10 Nov 2005 09:06:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750929AbVKJOG4 (ORCPT ); Thu, 10 Nov 2005 09:06:56 -0500 Received: from public.id2-vpn.continvity.gns.novell.com ([195.33.99.129]:23069 "EHLO emea1-mh.id2.novell.com") by vger.kernel.org with ESMTP id S1750911AbVKJOGz convert rfc822-to-8bit (ORCPT ); Thu, 10 Nov 2005 09:06:55 -0500 Message-Id: <4373624A.76F0.0078.0@novell.com> X-Mailer: Novell GroupWise Internet Agent 7.0 Date: Thu, 10 Nov 2005 15:07:54 +0100 From: "Jan Beulich" To: "Andi Kleen" Cc: , Subject: Re: [PATCH 20/39] NLKD/x86-64 - switch_to() floating point adjustment References: <43720DAE.76F0.0078.0@novell.com> <43721239.76F0.0078.0@novell.com> <4372127F.76F0.0078.0@novell.com> <200511101424.53484.ak@suse.de> In-Reply-To: <200511101424.53484.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >>> Andi Kleen 10.11.05 14:24:53 >>> >On Wednesday 09 November 2005 15:15, Jan Beulich wrote: >> Touching of the floating point state in a kernel debugger must be >> NMI-safe, specifically math_state_restore() must be able to deal with >> being called out of an NMI context. In order to do that reliably, the >> context switch code must take care to not leave a window open where >> the current task's TS_USEDFPU flag and CR0.TS could get out of sync. > >Didn't we agree earlier on moving unlazy_fpu() down instead? I wasn't sure about that, and hence I submitted it the way I had coded it. Jan