From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757207AbbE2TeH (ORCPT ); Fri, 29 May 2015 15:34:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58216 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756694AbbE2TeF (ORCPT ); Fri, 29 May 2015 15:34:05 -0400 Message-ID: <5568BF28.3040806@redhat.com> Date: Fri, 29 May 2015 21:34:00 +0200 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= CC: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, guangrong.xiao@linux.intel.com, bdas@redhat.com Subject: Re: [PATCH v2 00/13] SMM implementation for KVM References: <1432746314-50196-1-git-send-email-pbonzini@redhat.com> <20150529190305.GB7856@potion.brq.redhat.com> In-Reply-To: <20150529190305.GB7856@potion.brq.redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29/05/2015 21:03, Radim Krčmář wrote: > I found a corner case that doesn't fit any specific patch: > > We allow INIT while in SMM. This brings some security complications as > we also don't reset hflags (another long standing bug?), but we don't > really need to because INIT in SMM is against the spec anyway; > APM May 2013 2:10.3.3 Exceptions and Interrupts, > • INIT—The processor does not recognize INIT while in SMM. > > SDM April 2015: 34.5.1 Initial SMM Execution Environment, > Maskable hardware interrupts, exceptions, NMI interrupts, SMI > interrupts, A20M interrupts, single-step traps, breakpoint traps, and > INIT operations are inhibited when the processor enters SMM. > > And there is no mention of an exception for INIT. > (Some extra old experiments say that INIT could be enabled, but that is > not applicable now, http://www.rcollins.org/ddj/Mar97/Mar97.html) > > I think that INIT received before RSM should be delivered after. Yes. I'll look at it next week and post a 14th patch. Paolo