[PATCH v5 4/7] KVM: nVMX: Move the checks for VM-Exit Control Fields to a separate helper function

[Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>]

.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
Reviewed-by: Mihai Carabas <mihai.carabas@xxxxxxxxxx>
Reviewed-by: Mark Kanda <mark.kanda@xxxxxxxxxx>
---
 arch/x86/kvm/vmx.c | 43 +++++++++++++++++++++++++++++++++----------
 1 file changed, 33 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6fa48b7..2284b8f 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -12267,20 +12267,28 @@ static int nested_vmx_check_msr_switch(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
-static int nested_vmx_check_msr_switch_controls(struct kvm_vcpu *vcpu,
-						struct vmcs12 *vmcs12)
+static int nested_vmx_check_exit_msr_switch_controls(struct kvm_vcpu *vcpu,
+						     struct vmcs12 *vmcs12)
 {
 	if (nested_vmx_check_msr_switch(vcpu, vmcs12->vm_exit_msr_load_count,
 					vmcs12->vm_exit_msr_load_addr) ||
 	    nested_vmx_check_msr_switch(vcpu, vmcs12->vm_exit_msr_store_count,
-					vmcs12->vm_exit_msr_store_addr) ||
-	    nested_vmx_check_msr_switch(vcpu, vmcs12->vm_entry_msr_load_count,
-					vmcs12->vm_entry_msr_load_addr))
+					vmcs12->vm_exit_msr_store_addr))
 		return -EINVAL;
 
 	return 0;
 }
 
+static int nested_vmx_check_msr_switch_controls(struct kvm_vcpu *vcpu,
+                                                struct vmcs12 *vmcs12)
+{
+	if (nested_vmx_check_msr_switch(vcpu, vmcs12->vm_entry_msr_load_count,
+                                        vmcs12->vm_entry_msr_load_addr))
+                return -EINVAL;
+
+	return 0;
+}
+
 static int nested_vmx_check_pml_controls(struct kvm_vcpu *vcpu,
 					 struct vmcs12 *vmcs12)
 {
@@ -13046,6 +13054,23 @@ static int nested_check_vm_execution_controls(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
+/*
+ * Checks related to VM-Exit Control Fields
+ */
+static int nested_check_vm_exit_controls(struct kvm_vcpu *vcpu,
+                                         struct vmcs12 *vmcs12)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vmx_control_verify(vmcs12->vm_exit_controls,
+				vmx->nested.msrs.exit_ctls_low,
+				vmx->nested.msrs.exit_ctls_high) ||
+	    nested_vmx_check_exit_msr_switch_controls(vcpu, vmcs12))
+		return -EINVAL;
+
+	return 0;
+}
+
 static int nested_vmx_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
 					    struct vmcs12 *vmcs12)
 {
@@ -13055,7 +13080,8 @@ static int nested_vmx_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
 	    vmcs12->guest_activity_state != GUEST_ACTIVITY_HLT)
 		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
 
-	if (nested_check_vm_execution_controls(vcpu, vmcs12))
+	if (nested_check_vm_execution_controls(vcpu, vmcs12) ||
+	    nested_check_vm_exit_controls(vcpu, vmcs12))
 		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
 
 	if (nested_vmx_check_msr_switch_controls(vcpu, vmcs12))
@@ -13066,10 +13092,7 @@ static int nested_vmx_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
 	    !nested_cr3_valid(vcpu, vmcs12->host_cr3))
 		return VMXERR_ENTRY_INVALID_HOST_STATE_FIELD;
 
-	if (!vmx_control_verify(vmcs12->vm_exit_controls,
-				vmx->nested.msrs.exit_ctls_low,
-				vmx->nested.msrs.exit_ctls_high) ||
-	    !vmx_control_verify(vmcs12->vm_entry_controls,
+	if (!vmx_control_verify(vmcs12->vm_entry_controls,
 				vmx->nested.msrs.entry_ctls_low,
 				vmx->nested.msrs.entry_ctls_high))
 		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
-- 
2.9.5