From owner-freebsd-ports@FreeBSD.ORG Thu Apr 12 10:21:40 2007 Return-Path: X-Original-To: freebsd-ports@FreeBSD.org Delivered-To: freebsd-ports@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 2A8B616A402; Thu, 12 Apr 2007 10:21:40 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from gateway.cybervisiontech.com.ua (gateway.cybervisiontech.com.ua [88.81.251.18]) by mx1.freebsd.org (Postfix) with ESMTP id 6CDCC13C468; Thu, 12 Apr 2007 10:21:39 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from localhost (hq.cybervisiontech.com [127.0.0.1]) by gateway.cybervisiontech.com.ua (Postfix) with ESMTP id 26FB0ED49E0; Thu, 12 Apr 2007 13:21:30 +0300 (EEST) X-Virus-Scanned: amavisd-new at cybervisiontech.com Received: from gateway.cybervisiontech.com.ua ([127.0.0.1]) by localhost (hq.cybervisiontech.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id z8V-mfkjYYlN; Thu, 12 Apr 2007 13:21:28 +0300 (EEST) Received: from [10.2.1.87] (rein.cybervisiontech.com.ua [10.2.1.87]) by gateway.cybervisiontech.com.ua (Postfix) with ESMTP id 81774ED49C9; Thu, 12 Apr 2007 13:21:28 +0300 (EEST) Message-ID: <461E082B.8040401@icyb.net.ua> Date: Thu, 12 Apr 2007 13:21:31 +0300 From: Andriy Gapon User-Agent: Thunderbird 1.5.0.10 (X11/20070329) MIME-Version: 1.0 To: Jung-uk Kim References: <461CFD4B.4020801@icyb.net.ua> <200704111307.17455.jkim@FreeBSD.org> In-Reply-To: <200704111307.17455.jkim@FreeBSD.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-emulation@FreeBSD.org, Juergen Lock , freebsd-ports@FreeBSD.org Subject: Re: kqemu+amd64: fpudna in kernel mode X-BeenThere: freebsd-ports@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting software to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Apr 2007 10:21:40 -0000 on 11/04/2007 20:07 Jung-uk Kim said the following: > 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. > Jung-uk, thank you for the reply but there is still something not clear to me. I've read Bruce's response also, but I must admit I couldn't understand much. So, if floating point instructions cause trap then they apparently fail (or no ?), then why does (k)qemu executes them anyway ? And how (k)qemu is able to proceed normally after such failure ? -- Andriy Gapon