From f0495f9b9992f80f82b14306946444b287193390 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 7 Jun 2012 17:06:10 +0300 Subject: [PATCH] KVM: VMX: Relax check on unusable segment Some userspace (e.g. QEMU 1.1) munge the d and g bits of segment descriptors, causing us not to recognize them as unusable segments with emulate_invalid_guest_state=1. Relax the check by testing for segment not present (a non-present segment cannot be usable). Signed-off-by: Avi Kivity --- arch/x86/kvm/vmx.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 486db2f9561..82ab1fb2683 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3198,7 +3198,7 @@ static u32 vmx_segment_access_rights(struct kvm_segment *var) { u32 ar; - if (var->unusable) + if (var->unusable || !var->present) ar = 1 << 16; else { ar = var->type & 15; @@ -3210,8 +3210,6 @@ static u32 vmx_segment_access_rights(struct kvm_segment *var) ar |= (var->db & 1) << 14; ar |= (var->g & 1) << 15; } - if (ar == 0) /* a 0 value means unusable */ - ar = AR_UNUSABLE_MASK; return ar; } -- 2.20.1