From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932555AbaLDP5k (ORCPT ); Thu, 4 Dec 2014 10:57:40 -0500 Received: from mail-wg0-f52.google.com ([74.125.82.52]:35216 "EHLO mail-wg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932479AbaLDP5f (ORCPT ); Thu, 4 Dec 2014 10:57:35 -0500 From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: rkrcmar@redhat.com, Wanpeng Li Subject: [PATCH 6/9] KVM: cpuid: mask more bits in leaf 0xd and subleaves Date: Thu, 4 Dec 2014 16:57:11 +0100 Message-Id: <1417708634-24333-7-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1417708634-24333-1-git-send-email-pbonzini@redhat.com> References: <1417708634-24333-1-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 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 - EAX=0Dh, ECX=1: output registers ECX/EDX are reserved. - EAX=0Dh, ECX>1: output register ECX bit 0 is clear for all the CPUID leaves we support, because variable "supported" comes from XCR0 and not XSS. Bits above 0 are reserved, so ECX is overall zero. Output register EDX is reserved. Source: Intel Architecture Instruction Set Extensions Programming Reference, ref. number 319433-022 Reviewed-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 2f7bc2de9915..644bfe828ce1 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -482,8 +482,14 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry[i].ebx = xstate_required_size(supported, true); - } else if (entry[i].eax == 0 || !(supported & mask)) - continue; + } else { + if (entry[i].eax == 0 || !(supported & mask)) + continue; + if (WARN_ON_ONCE(entry[i].ecx & 1)) + continue; + } + entry[i].ecx = 0; + entry[i].edx = 0; entry[i].flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; ++*nent; -- 1.8.3.1