From owner-freebsd-emulation@FreeBSD.ORG Wed Apr 11 17:07:27 2007 Return-Path: X-Original-To: freebsd-emulation@FreeBSD.org Delivered-To: freebsd-emulation@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id DB6C316A401 for ; Wed, 11 Apr 2007 17:07:27 +0000 (UTC) (envelope-from jkim@FreeBSD.org) Received: from anuket.mj.niksun.com (gwnew.niksun.com [65.115.46.162]) by mx1.freebsd.org (Postfix) with ESMTP id 8A58313C45E for ; Wed, 11 Apr 2007 17:07:27 +0000 (UTC) (envelope-from jkim@FreeBSD.org) Received: from niksun.com (anuket [10.70.0.5]) by anuket.mj.niksun.com (8.13.6/8.13.6) with ESMTP id l3BH7JbZ066681; Wed, 11 Apr 2007 13:07:23 -0400 (EDT) (envelope-from jkim@FreeBSD.org) From: Jung-uk Kim To: freebsd-emulation@FreeBSD.org Date: Wed, 11 Apr 2007 13:07:15 -0400 User-Agent: KMail/1.6.2 References: <461CFD4B.4020801@icyb.net.ua> In-Reply-To: <461CFD4B.4020801@icyb.net.ua> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200704111307.17455.jkim@FreeBSD.org> X-Virus-Scanned: ClamAV 0.88.6/3068/Wed Apr 11 09:12:33 2007 on anuket.mj.niksun.com X-Virus-Status: Clean Cc: Andriy Gapon , freebsd-ports@FreeBSD.org, Juergen Lock Subject: Re: kqemu+amd64: fpudna in kernel mode X-BeenThere: freebsd-emulation@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Development of Emulators of other operating systems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Apr 2007 17:07:28 -0000 On Wednesday 11 April 2007 11:22 am, Andriy Gapon wrote: > I get swarms of messages "fpudna in kernel mode" in system log when > I run qemu with kqemu on FreeBSD 6.2 amd64 host with Windows XP > 32-bit guest. I noticed that someone reported this problem a while > ago: > http://lists.freebsd.org/pipermail/freebsd-emulation/2006-February/ >001800.html This happens because we do not allow FP instructions in kernel mode as the error message suggested. Executing FP instructions in kernel mode requires expensive save/restore cycles for FP states. > There is no harm done, but the messages are annoying and they might > be indicative of some bigger issue. > Note that I am running qemu like follows: > $ qemu-system-x86_64 ... -m 512 -net tap -net nic -localtime > > there is no -kernel-kqemu option and "info kqemu" in qemu monitor > says that it is enabled for user code. -kernel-kqemu option does not work for FreeBSD and it is very experimental feature for Linux x86-64. Since KQEMU is release under GPL recently, it can be fixed if someone's motivated enough, though. ;-) > As I understand "fpudna" means "FPU device not available" and the > message comes from here: > http://fxr.watson.org/fxr/source/amd64/amd64/trap.c > > on T_DNA ("device not avaialble") _kernel_ fault. You can ignore the complaints for now until we come up with better FP handling in kernel. > BTW, not complaining about the following, but I think I should > report it. When I use -kernel-kqemu option I get random crashes of > the guest XP (BSOD) with diagnostics like the following (they > vary): > > IRQL_NOT_GREATER_OR_EQUAL > PFN_LIST_CORRUPT > PAGE_FAULT_IN_NONPAGED_AREA > > Looks like all three are caused by some sort of memory corruption > or driver misbehavior according to the following: > http://aumha.org/a/stop.htm Windows guest is not supported by full virtualization mode, AFAIK. http://www.qemu.net/kqemu-doc.html BTW, it doesn't give you much performance gain as you may think: 'Best performances are achieved with Linux 2.4 kernels. Linux 2.6 works but the performance gains are small.' Even if we make it work with FreeBSD, I would expect similar results. Jung-uk Kim