KVM: nVMX: Provide EFER.LMA saving support
We will need EFER.LMA saving to provide unrestricted guest mode. All
what is missing for this is picking up EFER.LMA from VM_ENTRY_CONTROLS
on L2->L1 switches. If the host does not support EFER.LMA saving,
no change is performed, otherwise we properly emulate for L1 what the
hardware does for L0. Advertise the support, depending on the host
feature.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8eaabfb..02f8c32 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2022,6 +2022,7 @@
static u32 nested_vmx_pinbased_ctls_low, nested_vmx_pinbased_ctls_high;
static u32 nested_vmx_exit_ctls_low, nested_vmx_exit_ctls_high;
static u32 nested_vmx_entry_ctls_low, nested_vmx_entry_ctls_high;
+static u32 nested_vmx_misc_low, nested_vmx_misc_high;
static __init void nested_vmx_setup_ctls_msrs(void)
{
/*
@@ -2106,6 +2107,11 @@
nested_vmx_secondary_ctls_high &=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
SECONDARY_EXEC_WBINVD_EXITING;
+
+ /* miscellaneous data */
+ rdmsr(MSR_IA32_VMX_MISC, nested_vmx_misc_low, nested_vmx_misc_high);
+ nested_vmx_misc_low &= VMX_MISC_SAVE_EFER_LMA;
+ nested_vmx_misc_high = 0;
}
static inline bool vmx_control_verify(u32 control, u32 low, u32 high)
@@ -2176,7 +2182,8 @@
nested_vmx_entry_ctls_high);
break;
case MSR_IA32_VMX_MISC:
- *pdata = 0;
+ *pdata = vmx_control_msr(nested_vmx_misc_low,
+ nested_vmx_misc_high);
break;
/*
* These MSRs specify bits which the guest must keep fixed (on or off)
@@ -7398,6 +7405,10 @@
vmcs12->guest_pending_dbg_exceptions =
vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS);
+ vmcs12->vm_entry_controls =
+ (vmcs12->vm_entry_controls & ~VM_ENTRY_IA32E_MODE) |
+ (vmcs_read32(VM_ENTRY_CONTROLS) & VM_ENTRY_IA32E_MODE);
+
/* TODO: These cannot have changed unless we have MSR bitmaps and
* the relevant bit asks not to trap the change */
vmcs12->guest_ia32_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL);