Commit e504c909 authored Nov 13, 2013 by Anthoine Bourgeois Committed by Paolo Bonzini Nov 13, 2013

kvm, vmx: Fix lazy FPU on nested guest



If a nested guest does a NM fault but its CR0 doesn't contain the TS
flag (because it was already cleared by the guest with L1 aid) then we
have to activate FPU ourselves in L0 and then continue to L2. If TS flag
is set then we fallback on the previous behavior, forward the fault to
L1 if it asked for.

Signed-off-by: Anthoine Bourgeois <bourgeois@bertin.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent ede58222

arch/x86/kvm/vmx.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -6643,6 +6643,9 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
		return 0;
		else if (is_page_fault(intr_info))
		return enable_ept;
		else if (is_no_device(intr_info) &&
		!(nested_read_cr0(vmcs12) & X86_CR0_TS))
		return 0;
		return vmcs12->exception_bitmap &
		(1u << (intr_info & INTR_INFO_VECTOR_MASK));
		case EXIT_REASON_EXTERNAL_INTERRUPT: