Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754588AbYHLAzh (ORCPT ); Mon, 11 Aug 2008 20:55:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750899AbYHLAz0 (ORCPT ); Mon, 11 Aug 2008 20:55:26 -0400 Received: from terminus.zytor.com ([198.137.202.10]:57582 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750869AbYHLAz0 (ORCPT ); Mon, 11 Aug 2008 20:55:26 -0400 Message-ID: <48A0DDEC.704@zytor.com> Date: Mon, 11 Aug 2008 17:48:44 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Herbert Xu CC: Suresh Siddha , Ingo Molnar , Wolfgang Walter , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "viro@ZenIV.linux.org.uk" , "vegard.nossum@gmail.com" , Thomas Gleixner Subject: Re: Kernel oops with 2.6.26, padlock and ipsec: probably problem with fpu state changes References: <489DC15D.9070308@zytor.com> <20080809185224.GH13158@linux-os.sc.intel.com> <20080809193724.GJ13158@linux-os.sc.intel.com> <20080810030521.GA2332@gondor.apana.org.au> <20080811190131.GL13158@linux-os.sc.intel.com> <20080811192203.GC12788@elte.hu> <48A0920B.30306@zytor.com> <20080811201901.GN13158@linux-os.sc.intel.com> <20080812003938.GC18230@gondor.apana.org.au> <48A0DC6D.8040409@zytor.com> <20080812004641.GB18444@gondor.apana.org.au> In-Reply-To: <20080812004641.GB18444@gondor.apana.org.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1041 Lines: 23 Herbert Xu wrote: > On Mon, Aug 11, 2008 at 05:42:21PM -0700, H. Peter Anvin wrote: >> That's not sufficient, though, because you have to track all the state >> and how it relates to everything. You now have to track both the >> userspace FPU state and the potential kernel FPU state. The VIA >> instructions are special (in the short bus to school sense) in that they >> use a mechanism intended to protect specific state to protect -- exactly >> nothing. > > Sorry, the kernel TS state is what I meant. I'm definitely not > advocating the saving of the kernel FPU state. This is only for > things like the VIA (which also exists for other processors, see > the xor SSE stuff in include/asm-x86). No, there you are actually using the FPU state (which includes the SSE state.) -hpa -- 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/