From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Question about EMULATE_DO_MMIO Date: Wed, 17 Oct 2007 12:50:14 +0200 Message-ID: <4715E8E6.2030708@qumranet.com> References: <1192559057.2488.5.camel@lnitindesktop.sc.intel.com> <47151B38.1070402@qumranet.com> <1192566489.2488.10.camel@lnitindesktop.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel To: nitin.a.kamble-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org Return-path: In-Reply-To: <1192566489.2488.10.camel-mpPvwfgnXtFHIUuj5cj4Omt3HXsI98Cx0E9HWUfgJXw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Nitin A Kamble wrote: > On Tue, 2007-10-16 at 13:12 -0700, Avi Kivity wrote: > > >> Why do you think it is better? I would have thought that vm86 is much >> faster. >> >> > I am seeing execution going to strange places in vm86 mode. That issue > is not coming in the emulation. > > That means there's a bug somewhere. We need to fix it. >> That will also handle the few cases where VT can't handle protected >> mode. >> >> It should exit to userspace, same as the non-emulating case. However >> it >> shouldn't happen for normal writes. >> >> > Only thing is if it in the real mode, then returning back to user mode > will setup the cpu state as real mode, and because of that vmenter will > fail. > It will fail, and we'll see it and go back to emulation. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/