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authorJan Kiszka2013-08-08 16:26:33 +0200
committerPaolo Bonzini2013-09-24 19:12:15 +0200
commit92fbc7b195b824e201d9f06f2b93105f72384d65 (patch)
treee5f9b87ece9ed103076795fb42fe4b3587a225de /arch/x86/kvm
parentKVM: nVMX: Implement support for EFER saving on VM-exit (diff)
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KVM: nVMX: Enable unrestricted guest mode support
Now that we provide EPT support, there is no reason to torture our guests by hiding the relieving unrestricted guest mode feature. We just need to relax CR0 checks for always-on bits as PE and PG can now be switched off. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r--arch/x86/kvm/vmx.c18
1 files changed, 14 insertions, 4 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 58d07a1ced69..e6e8fbc02d5e 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2252,6 +2252,7 @@ static __init void nested_vmx_setup_ctls_msrs(void)
nested_vmx_secondary_ctls_low = 0;
nested_vmx_secondary_ctls_high &=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
+ SECONDARY_EXEC_UNRESTRICTED_GUEST |
SECONDARY_EXEC_WBINVD_EXITING;
if (enable_ept) {
@@ -4877,6 +4878,17 @@ vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
hypercall[2] = 0xc1;
}
+static bool nested_cr0_valid(struct vmcs12 *vmcs12, unsigned long val)
+{
+ unsigned long always_on = VMXON_CR0_ALWAYSON;
+
+ if (nested_vmx_secondary_ctls_high &
+ SECONDARY_EXEC_UNRESTRICTED_GUEST &&
+ nested_cpu_has2(vmcs12, SECONDARY_EXEC_UNRESTRICTED_GUEST))
+ always_on &= ~(X86_CR0_PE | X86_CR0_PG);
+ return (val & always_on) == always_on;
+}
+
/* called to set cr0 as appropriate for a mov-to-cr0 exit. */
static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val)
{
@@ -4895,9 +4907,7 @@ static int handle_set_cr0(struct kvm_vcpu *vcpu, unsigned long val)
val = (val & ~vmcs12->cr0_guest_host_mask) |
(vmcs12->guest_cr0 & vmcs12->cr0_guest_host_mask);
- /* TODO: will have to take unrestricted guest mode into
- * account */
- if ((val & VMXON_CR0_ALWAYSON) != VMXON_CR0_ALWAYSON)
+ if (!nested_cr0_valid(vmcs12, val))
return 1;
if (kvm_set_cr0(vcpu, val))
@@ -7876,7 +7886,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch)
return 1;
}
- if (((vmcs12->guest_cr0 & VMXON_CR0_ALWAYSON) != VMXON_CR0_ALWAYSON) ||
+ if (!nested_cr0_valid(vmcs12, vmcs12->guest_cr0) ||
((vmcs12->guest_cr4 & VMXON_CR4_ALWAYSON) != VMXON_CR4_ALWAYSON)) {
nested_vmx_entry_failure(vcpu, vmcs12,
EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT);