From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: Etherboot problems Date: Thu, 09 Nov 2006 20:32:34 -0600 Message-ID: <4553E4C2.1050801@cs.utexas.edu> References: <874pt8ip14.wl%simon.kagstrom@bth.se> <455354AB.8000908@qumranet.com> <45536A11.6050808@qumranet.com> <873b8sij7k.wl%simon.kagstrom@bth.se> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Return-path: To: Simon Kagstrom In-Reply-To: <873b8sij7k.wl%simon.kagstrom-6Uc+yI3S9P8@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 Simon Kagstrom wrote: >> Very likely this is due to VT's inability to virtualize real mode >> correctly. Is anyone in the mood to extend x86_emulate.c to support >> real mode? > > I forgot to add that I've tested it in Xen as well, and it works > there. Maybe someone has an AMD at hand to test it on? > > But I also suspected that this was the reason why it failed. I ran a > diff between x86_emulate.c in Xen and KVM but couldn't immediately see > any differences which would explain this. Xen doesn't use x86_emulate.c for real mode. It uses vmxassist which uses vm86 mode (yes, there are many many emulators in Xen). Xen 3.0.4 is planning on dropping vmxassist in favor of CPU state hand off between QEMU and Xen. This would be much easier in KVM ATM as it doesn't require state synchronization for hardware emulation. Regards, Anthony Liguori ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642