From 9d978f7cf24e6451af158eb5da483193010c10f0 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 6 Aug 2009 14:39:59 -0300 Subject: [PATCH] KVM: SVM: Remove port 80 passthrough MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit (cherry picked from commit 99f85a28a78e96d28907fe036e1671a218fee597) 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(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 8233b86c778..77cae0107c3 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -429,7 +429,6 @@ static __init int svm_hardware_setup(void) 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)) -- 2.11.4.GIT