[PATCH v1 05/23] KVM: VMX: Initialize FRED VM entry/exit controls in vmcs_config

[Xin Li]

Setup the global vmcs_config for FRED:
1) Add VM_ENTRY_LOAD_IA32_FRED to KVM_OPTIONAL_VMX_VM_ENTRY_CONTROLS to
   have a FRED CPU load guest FRED MSRs from VMCS upon VM entry.
2) Add SECONDARY_VM_EXIT_SAVE_IA32_FRED to
   KVM_OPTIONAL_VMX_SECONDARY_VM_EXIT_CONTROLS to have a FRED CPU save
   guest FRED MSRs to VMCS during VM exit.
3) add SECONDARY_VM_EXIT_LOAD_IA32_FRED to
   KVM_OPTIONAL_VMX_SECONDARY_VM_EXIT_CONTROLS to have a FRED CPU load
   host FRED MSRs from VMCS during VM exit.

Also add sanity checks to make sure FRED VM entry/exit controls can be
set on a FRED CPU.

Tested-by: Shan Kang <shan.kang@xxxxxxxxx>
Signed-off-by: Xin Li <xin3.li@xxxxxxxxx>
---
 arch/x86/include/asm/vmx.h |  3 +++
 arch/x86/kvm/vmx/vmx.c     | 19 ++++++++++++++++++-
 arch/x86/kvm/vmx/vmx.h     |  7 +++++--
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 4d4177ec802c..41796a733bc9 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -106,6 +106,8 @@
 #define VM_EXIT_PT_CONCEAL_PIP			0x01000000
 #define VM_EXIT_CLEAR_IA32_RTIT_CTL		0x02000000
 #define VM_EXIT_ACTIVATE_SECONDARY_CONTROLS	0x80000000
+#define SECONDARY_VM_EXIT_SAVE_IA32_FRED	0x00000001
+#define SECONDARY_VM_EXIT_LOAD_IA32_FRED	0x00000002
 
 #define VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR	0x00036dff
 
@@ -119,6 +121,7 @@
 #define VM_ENTRY_LOAD_BNDCFGS                   0x00010000
 #define VM_ENTRY_PT_CONCEAL_PIP			0x00020000
 #define VM_ENTRY_LOAD_IA32_RTIT_CTL		0x00040000
+#define VM_ENTRY_LOAD_IA32_FRED			0x00800000
 
 #define VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR	0x000011ff
 
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index df769207cbe0..9186f41974ab 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2694,10 +2694,27 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
 		_vmexit_control &= ~x_ctrl;
 	}
 
-	if (_vmexit_control & VM_EXIT_ACTIVATE_SECONDARY_CONTROLS)
+	if (_vmexit_control & VM_EXIT_ACTIVATE_SECONDARY_CONTROLS) {
 		_secondary_vmexit_control =
 			adjust_vmx_controls64(KVM_OPTIONAL_VMX_SECONDARY_VM_EXIT_CONTROLS,
 					      MSR_IA32_VMX_EXIT_CTLS2);
+		if (cpu_feature_enabled(X86_FEATURE_FRED) &&
+		    !(_secondary_vmexit_control & SECONDARY_VM_EXIT_SAVE_IA32_FRED &&
+		      _secondary_vmexit_control & SECONDARY_VM_EXIT_LOAD_IA32_FRED)) {
+			pr_warn_once("FRED enabled but no VMX VM-Exit {SAVE,LOAD}_IA32_FRED controls: %llx\n",
+				     _secondary_vmexit_control);
+			if (error_on_inconsistent_vmcs_config)
+				return -EIO;
+		}
+	}
+
+	if (cpu_feature_enabled(X86_FEATURE_FRED) &&
+	    !(_vmentry_control & VM_ENTRY_LOAD_IA32_FRED)) {
+		pr_warn_once("FRED enabled but no VMX VM-Entry LOAD_IA32_FRED control: %x\n",
+			     _vmentry_control);
+		if (error_on_inconsistent_vmcs_config)
+			return -EIO;
+	}
 
 	rdmsrl(MSR_IA32_VMX_BASIC, basic_msr);
 
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 99a0f6783085..f8c02bd37069 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -480,7 +480,8 @@ static inline u8 vmx_get_rvi(void)
 	 VM_ENTRY_LOAD_IA32_EFER |					\
 	 VM_ENTRY_LOAD_BNDCFGS |					\
 	 VM_ENTRY_PT_CONCEAL_PIP |					\
-	 VM_ENTRY_LOAD_IA32_RTIT_CTL)
+	 VM_ENTRY_LOAD_IA32_RTIT_CTL |					\
+	 VM_ENTRY_LOAD_IA32_FRED)
 
 #define __KVM_REQUIRED_VMX_VM_EXIT_CONTROLS				\
 	(VM_EXIT_SAVE_DEBUG_CONTROLS |					\
@@ -506,7 +507,9 @@ static inline u8 vmx_get_rvi(void)
 	       VM_EXIT_ACTIVATE_SECONDARY_CONTROLS)
 
 #define KVM_REQUIRED_VMX_SECONDARY_VM_EXIT_CONTROLS (0)
-#define KVM_OPTIONAL_VMX_SECONDARY_VM_EXIT_CONTROLS (0)
+#define KVM_OPTIONAL_VMX_SECONDARY_VM_EXIT_CONTROLS			\
+	     (SECONDARY_VM_EXIT_SAVE_IA32_FRED |			\
+	      SECONDARY_VM_EXIT_LOAD_IA32_FRED)
 
 #define KVM_REQUIRED_VMX_PIN_BASED_VM_EXEC_CONTROL			\
 	(PIN_BASED_EXT_INTR_MASK |					\
-- 
2.42.0