From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755375AbZDUQBV (ORCPT ); Tue, 21 Apr 2009 12:01:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752215AbZDUQBG (ORCPT ); Tue, 21 Apr 2009 12:01:06 -0400 Received: from mx2.redhat.com ([66.187.237.31]:57638 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750842AbZDUQBF (ORCPT ); Tue, 21 Apr 2009 12:01:05 -0400 Message-ID: <49EDEDAD.20900@redhat.com> Date: Tue, 21 Apr 2009 18:00:45 +0200 From: Gerd Hoffmann User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1b3pre) Gecko/20090324 Fedora/3.0-2.1.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: Avi Kivity CC: Anthony Liguori , Huang Ying , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Andi Kleen Subject: Re: Xenner design and kvm msr handling References: <1239155601.6384.3.camel@yhuang-dev.sh.intel.com> <49DE195D.1020303@redhat.com> <1239332455.6384.108.camel@yhuang-dev.sh.intel.com> <49E08762.1010206@redhat.com> <1239590499.6384.4016.camel@yhuang-dev.sh.intel.com> <49E337D7.5050502@redhat.com> <49EA515C.9000507@codemonkey.ws> <49EAE1F6.9050205@redhat.com> <49EC29D1.8040407@redhat.com> <49EC3198.9070902@redhat.com> <49EC3987.2040001@redhat.com> <49EC3AD6.3090905@redhat.com> <49EC5B2A.9080403@redhat.com> <49EC5C3A.6020108@redhat.com> <49EC68A7.8080403@redhat.com> <49EC6DEE.4070703@redhat.com> <49EC7797.7060004@redhat.com> <49EC7C5F.2000006@redhat.com> <49ED8E6D.80005@redhat.com> <49ED9C70.5010906@redhat.com> <49EDB0E0.5060101@redhat.com> <49EDBBBF.90509@redhat.com> <49EDC050.1040700@redhat.com> <49EDCB1D.1010301@redhat.com> In-Reply-To: <49EDCB1D.1010301@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/21/09 15:33, Avi Kivity wrote: > Gerd Hoffmann wrote: >> Not sure, have to dig into the xen code to figure. >> >> Could be xen doesn't remember the page in the first place. They might >> let the illegal instruction fault handler patch the opcode. At least I >> vaguely remember some discussions about that. Xen does a simple msr-triggered memcpy() as well, without keeping track of the page. On a quick glimpse I can't find a opcode patching place either. Hmm. >> Could be there isn't a interface to forgot the page. "reboot" in xen >> land is "destroy guest, restart it". > > How do you unload a driver then? The linux module (xen-platform-pci) has no module_exit() ... cheers, Gerd