summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorAvi Kivity <avi@redhat.com>2009-05-11 14:21:10 +0300
committerAvi Kivity <avi@redhat.com>2009-05-11 14:40:51 +0300
commit99f85a28a78e96d28907fe036e1671a218fee597 (patch)
tree7d24df5b4d27d6801b1c372297adffb2334d9a97 /arch
parente286e86e6d2042d67d09244aa0e05ffef75c9d54 (diff)
KVM: SVM: Remove port 80 passthrough
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. Cc: stable@kernel.org Reported-by: Piotr Jaroszyński <p.jaroszynski@gmail.com> Tested-by: Piotr Jaroszyński <p.jaroszynski@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kvm/svm.c1
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 9184e32778a..1f8510c51d6 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -411,7 +411,6 @@ 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))