[PATCH v3 04/27] KVM: VMX: Initialize FRED VM entry/exit controls in vmcs_config

From: Xin Li (Intel)
Date: Tue Oct 01 2024 - 01:06:47 EST


From: Xin Li <xin3.li@xxxxxxxxx>

Setup FRED VM entry/exit controls in the global vmcs_config for proper
FRED VMCS fields management, i.e., load guest FRED state upon VM entry,
and save guest/load host FRED state during VM exit.

Signed-off-by: Xin Li <xin3.li@xxxxxxxxx>
Signed-off-by: Xin Li (Intel) <xin@xxxxxxxxx>
Tested-by: Shan Kang <shan.kang@xxxxxxxxx>
Reviewed-by: Chao Gao <chao.gao@xxxxxxxxx>
---

Change since v2:
* Add FRED VM entry/exit controls consistency checks to the existing
consistency check framework (Sean Christopherson).
* Just do the unnecessary FRED state load/store on entry/exit (Sean
Christopherson).
---
arch/x86/include/asm/vmx.h | 4 ++++
arch/x86/kvm/vmx/vmx.c | 2 ++
arch/x86/kvm/vmx/vmx.h | 7 +++++--
3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 57a37ea06a17..551f62892e1a 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -108,6 +108,9 @@
#define VM_EXIT_CLEAR_IA32_RTIT_CTL 0x02000000
#define VM_EXIT_ACTIVATE_SECONDARY_CONTROLS 0x80000000

+#define SECONDARY_VM_EXIT_SAVE_IA32_FRED BIT_ULL(0)
+#define SECONDARY_VM_EXIT_LOAD_IA32_FRED BIT_ULL(1)
+
#define VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR 0x00036dff

#define VM_ENTRY_LOAD_DEBUG_CONTROLS 0x00000004
@@ -120,6 +123,7 @@
#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 ec548c75c3ef..efd2ad397ad2 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2627,6 +2627,8 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
{ VM_ENTRY_LOAD_IA32_EFER, VM_EXIT_LOAD_IA32_EFER },
{ VM_ENTRY_LOAD_BNDCFGS, VM_EXIT_CLEAR_BNDCFGS },
{ VM_ENTRY_LOAD_IA32_RTIT_CTL, VM_EXIT_CLEAR_IA32_RTIT_CTL },
+ { VM_ENTRY_LOAD_IA32_FRED, VM_EXIT_ACTIVATE_SECONDARY_CONTROLS,
+ SECONDARY_VM_EXIT_SAVE_IA32_FRED | SECONDARY_VM_EXIT_LOAD_IA32_FRED },
};

memset(vmcs_conf, 0, sizeof(*vmcs_conf));
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index cf3a6c116634..e0d76d2460ef 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -485,7 +485,8 @@ 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 | \
@@ -511,7 +512,9 @@ 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 | \
--
2.46.2