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authorPaolo Bonzini <pbonzini@redhat.com>2014-02-27 22:54:11 +0100
committerPaolo Bonzini <pbonzini@redhat.com>2014-02-27 22:54:11 +0100
commit1b385cbdd74aa803e966e01e5fe49490d6044e30 (patch)
treeba74b3cac9727b3cacda97775729269b7f92781e
parenta08d3b3b99efd509133946056531cdf8f3a0c09b (diff)
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kvm, vmx: Really fix lazy FPU on nested guest
Commit e504c9098ed6 (kvm, vmx: Fix lazy FPU on nested guest, 2013-11-13) highlighted a real problem, but the fix was subtly wrong. nested_read_cr0 is the CR0 as read by L2, but here we want to look at the CR0 value reflecting L1's setup. In other words, L2 might think that TS=0 (so nested_read_cr0 has the bit clear); but if L1 is actually running it with TS=1, we should inject the fault into L1. The effective value of CR0 in L2 is contained in vmcs12->guest_cr0, use it. Fixes: e504c9098ed6acd9e1079c5e10e4910724ad429f Reported-by: Kashyap Chamarty <kchamart@redhat.com> Reported-by: Stefan Bader <stefan.bader@canonical.com> Tested-by: Kashyap Chamarty <kchamart@redhat.com> Tested-by: Anthoine Bourgeois <bourgeois@bertin.fr> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
-rw-r--r--arch/x86/kvm/vmx.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index a06f101ef64b..392752834751 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6688,7 +6688,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu)
else if (is_page_fault(intr_info))
return enable_ept;
else if (is_no_device(intr_info) &&
- !(nested_read_cr0(vmcs12) & X86_CR0_TS))
+ !(vmcs12->guest_cr0 & X86_CR0_TS))
return 0;
return vmcs12->exception_bitmap &
(1u << (intr_info & INTR_INFO_VECTOR_MASK));