Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757103Ab2B1LVX (ORCPT ); Tue, 28 Feb 2012 06:21:23 -0500 Received: from mx1.redhat.com ([209.132.183.28]:4640 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752283Ab2B1LVV (ORCPT ); Tue, 28 Feb 2012 06:21:21 -0500 Message-ID: <4F4CB89C.4060500@redhat.com> Date: Tue, 28 Feb 2012 13:21:00 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Linus Torvalds CC: "H. Peter Anvin" , Josh Boyer , Jongman Heo , Thomas Gleixner , Ingo Molnar , x86@kernel.org, Linux Kernel Mailing List , KVM list Subject: Re: [PATCH 2/2] i387: split up into exported and internal interfaces References: <4F42FE08.5020309@zytor.com> <4F43DB69.9060509@zytor.com> <4F440945.1020904@zytor.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1201 Lines: 27 On 02/21/2012 11:41 PM, Linus Torvalds wrote: > Btw, I really don't like what arch/x86/kvm/ does with CR0.TS and the FP > state. I'm not at all sure that's all kosher. But I don't know the > code, so I just made sure that at no point did any of the semantics > change. > Can you elaborate on what you don't like in the kvm code (apart from "it does virtualiztion")? btw, some time ago I did some work to lazify fpu save (as opposed to just fpu restore) and abstract out the various users (user mode, kernel threads, irq context, guest mode, and signal handlers). This would allow you to run task A's user mode with task B's fpu loaded, have preemptible kernel fpu being, avoid fpu switching while handling signals, and run user mode with a guest fpu loaded or vice versa. However I abandoned the effort as too complex. Perhaps a more determined hacker can make more progress there. -- error compiling committee.c: too many arguments to function -- 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/