From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH 2/3] KVM: x86: Save&restore interrupt shadow mask Date: Wed, 17 Feb 2010 10:07:12 +0100 Message-ID: <4B7BB1C0.2060200@siemens.com> References: <0bc4d8c46c0868cff70568bb5ee6df25162ddab6.1266227138.git.jan.kiszka@siemens.com> <20100217003941.GA1110@amt.cnet> <4B7BA374.4040102@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , Avi Kivity , kvm To: Zachary Amsden Return-path: Received: from goliath.siemens.de ([192.35.17.28]:17488 "EHLO goliath.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934200Ab0BQJHa (ORCPT ); Wed, 17 Feb 2010 04:07:30 -0500 In-Reply-To: <4B7BA374.4040102@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Zachary Amsden wrote: > On 02/16/2010 02:39 PM, Marcelo Tosatti wrote: >> On Mon, Feb 15, 2010 at 10:45:42AM +0100, Jan Kiszka wrote: >> >>> The interrupt shadow created by STI or MOV-SS-like operations is part of >>> the VCPU state and must be preserved across migration. Transfer it in >>> the spare padding field of kvm_vcpu_events.interrupt. > > STI and MOV-SS interrupt shadow are both treated differently by > hardware. Any attempt to unify them into a single field is wrong, > especially so in a hardware virtualization context, where they are > actually represented by different fields in the undocumented but > nevertheless extant format that can be inferred from the hardware > virtualization context used by specific vendors. Someone should ask AMD why they thought differently about this while designing SVM... Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux