From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755536Ab1HRKps (ORCPT ); Thu, 18 Aug 2011 06:45:48 -0400 Received: from a.ns.miles-group.at ([95.130.255.143]:54722 "EHLO radon.swed.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755166Ab1HRKpq (ORCPT ); Thu, 18 Aug 2011 06:45:46 -0400 Message-ID: <4E4CED56.1030100@nod.at> Date: Thu, 18 Aug 2011 12:45:42 +0200 From: Richard Weinberger User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:6.0) Gecko/20110812 Thunderbird/6.0 MIME-Version: 1.0 To: Stanislav Meduna CC: linux-kernel@vger.kernel.org, gunnarlindroth@hotmail.com, user-mode-linux-devel@lists.sourceforge.net, inguin@gmx.de Subject: Re: [uml-devel] Floating point problems on UML - help needed References: <4E4C2B6F.7000800@nod.at> <4E4CB13C.7010502@meduna.org> In-Reply-To: <4E4CB13C.7010502@meduna.org> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 18.08.2011 08:29, schrieb Stanislav Meduna: > On 17.08.2011 22:58, Richard Weinberger wrote: > >> It looks like FPU registers get sometimes lost after switching between >> two or more threads. > > This is probably a bug in UML I reported nearly three years ago. > For me mode=skas0 worked aruond the issue. > > http://thread.gmane.org/gmane.linux.uml.devel/11824/focus=11840 > > You might try the patch posted in > http://thread.gmane.org/gmane.linux.uml.devel/12158 > (I don't have the environment to test it anymore) Cool, saving the FP registers explicitly on each task switch solves the issue. Do you know why Ingo's patch was never applied? Ingo? Thanks, //richard