From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762089AbZENW5M (ORCPT ); Thu, 14 May 2009 18:57:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757064AbZENWmx (ORCPT ); Thu, 14 May 2009 18:42:53 -0400 Received: from kroah.org ([198.145.64.141]:52658 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756470AbZENWme (ORCPT ); Thu, 14 May 2009 18:42:34 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Thu May 14 15:35:27 2009 Message-Id: <20090514223527.514350123@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Thu, 14 May 2009 15:33:18 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Avi Kivity Subject: [patch 43/51] KVM: SVM: Remove port 80 passthrough References: <20090514223235.348540705@mini.kroah.org> Content-Disposition: inline; filename=kvm-svm-remove-port-80-passthrough.patch In-Reply-To: <20090514223755.GA27019@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.29-stable review patch. If anyone has any objections, please let us know. ------------------ From: Avi Kivity commit 99f85a28a78e96d28907fe036e1671a218fee597 upstream. KVM optimizes guest port 80 accesses by passthing them through to the host. Some AMD machines die on port 80 writes, allowing the guest to hard-lock the host. Remove the port passthrough to avoid the problem. Reported-by: Piotr Jaroszyński Tested-by: Piotr Jaroszyński Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm.c | 1 - 1 file changed, 1 deletion(-) --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -411,7 +411,6 @@ static __init int svm_hardware_setup(voi iopm_va = page_address(iopm_pages); memset(iopm_va, 0xff, PAGE_SIZE * (1 << IOPM_ALLOC_ORDER)); - clear_bit(0x80, iopm_va); /* allow direct access to PC debug port */ iopm_base = page_to_pfn(iopm_pages) << PAGE_SHIFT; if (boot_cpu_has(X86_FEATURE_NX))