Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933287AbcKNLAa (ORCPT ); Mon, 14 Nov 2016 06:00:30 -0500 Received: from lxorguk.ukuu.org.uk ([81.2.110.251]:60940 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932310AbcKNLA2 (ORCPT ); Mon, 14 Nov 2016 06:00:28 -0500 Date: Mon, 14 Nov 2016 10:59:11 +0000 From: One Thousand Gnomes To: Ricardo Neri Cc: Andy Lutomirski , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "linux-kernel@vger.kernel.org" , X86 ML , "linux-doc@vger.kernel.org" , Andy Lutomirski , Andrew Morton , Borislav Petkov , Brian Gerst , Chen Yucong , Chris Metcalf , Dave Hansen , Fenghua Yu , Huang Rui , Jiri Slaby , Jonathan Corbet , "Michael S . Tsirkin" , Paul Gortmaker , "Ravi V . Shankar" , Vlastimil Babka , Shuah Khan , linux-msdos@vger.kernel.org Subject: Re: [PATCH 0/4] x86: enable User-Mode Instruction Prevention Message-ID: <20161114105911.62a6821c@lxorguk.ukuu.org.uk> In-Reply-To: <1478760361.2551.21.camel@ranerica-desktop> References: <1478585533-19406-1-git-send-email-ricardo.neri-calderon@linux.intel.com> <20161108131600.GF3117@twins.programming.kicks-ass.net> <1478665889.2533.8.camel@ranerica-desktop> <1478760361.2551.21.camel@ranerica-desktop> Organization: Intel Corporation X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 643 Lines: 15 > I took a closer look at the dosemu code. It appears that it does not That doesn't tell you want DOS itself will try and do... > purposely utilize SGDT to obtain the descriptor table while in vm86. It > does use SGDT (in protected mode) to emulate certain functionality such > as the Virtual xxx Driver. In such a case, UMIP needs to be disabled. > However, this code seems to be disabled [1]. dosemu includes an i386 > emulator that in some cases uses the actual instructions of the host > system. In such cases, UMIP might be needed to be disabled. Is anyone actually still using DOSemu these days or are people all using DOSbox ? Alan