From 495e116684cebc5ae625916aba37fc07f345707b Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Tue, 21 Aug 2012 17:07:02 +0300 Subject: [PATCH] KVM: VMX: Allow real mode emulation using vm86 with dpl=0 Real mode is always entered from protected mode with dpl=0. Since the dpl doesn't affect execution, and we already override it to 3 in the vmcs (as vmx requires), we can allow execution in that state. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/vmx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 88eeb40..4811d91 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3317,7 +3317,7 @@ static bool rmode_segment_valid(struct kvm_vcpu *vcpu, int seg) return false; if (var.limit != 0xffff) return false; - if (ar != 0xf3) + if ((ar | (3 << AR_DPL_SHIFT)) != 0xf3) return false; return true; -- 2.7.4