Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030241AbWIRWwj (ORCPT ); Mon, 18 Sep 2006 18:52:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030243AbWIRWwi (ORCPT ); Mon, 18 Sep 2006 18:52:38 -0400 Received: from smtp.osdl.org ([65.172.181.4]:17606 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1030241AbWIRWwh (ORCPT ); Mon, 18 Sep 2006 18:52:37 -0400 Date: Mon, 18 Sep 2006 15:52:14 -0700 (PDT) From: Linus Torvalds To: Jesper Juhl cc: Linux Kernel Mailing List , billm@melbpc.org.au, billm@suburbia.net Subject: Re: Math-emu kills the kernel on Athlon64 X2 In-Reply-To: <9a8748490609181518j2d12e4f0l2c55e755e40d38c2@mail.gmail.com> Message-ID: References: <9a8748490609181518j2d12e4f0l2c55e755e40d38c2@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 996 Lines: 27 On Tue, 19 Sep 2006, Jesper Juhl wrote: > > If I enable the math emulator in 2.6.18-rc7-git2 (only version I've > tried this with) and then boot the kernel with "no387" then I only get > as far as lilo's "...Booting the kernel." message and then the system > hangs. I'm wondering if it tries to use the MMX/XMM stuff for memcpy and friends. I'm also wondering why you'd be doing what you seem to try to be doing in the first place ;) Basically, "no387" doesn't seem to disable any of the fancier FPU features, even though it obviously should. If you ask for math emulation, you'll get emulation faults for _all_ of the modern MMX stuff too (which we don't do). It's entirely possible that nobody has ever tested this combination. Linus - 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/