[PATCH v1 03/23] KVM: VMX: Add support for the secondary VM exit controls

Xin Li
2023-11-08T19:00:27Z

Enable the secondary VM exit controls to prepare for FRED enabling.

The activation of the secondary VM exit controls is off now, and it
will be switched on when a VMX feature needing it is enabled.

Tested-by: Shan Kang <shan.kang@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
---
arch/x86/include/asm/msr-index.h | 1 +
arch/x86/include/asm/vmx.h | 3 +++
arch/x86/kvm/vmx/capabilities.h | 9 ++++++++-
arch/x86/kvm/vmx/vmcs.h | 1 +
arch/x86/kvm/vmx/vmx.c | 28 +++++++++++++++++++++++++---
arch/x86/kvm/vmx/vmx.h | 7 ++++++-
6 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index d7d4eace5dae..c95ed288aa5d 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -1109,6 +1109,7 @@
#define MSR_IA32_VMX_TRUE_ENTRY_CTLS 0x00000490
#define MSR_IA32_VMX_VMFUNC 0x00000491
#define MSR_IA32_VMX_PROCBASED_CTLS3 0x00000492
+#define MSR_IA32_VMX_EXIT_CTLS2 0x00000493

/* Resctrl MSRs: */
/* - Intel: */
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 5771c5751e7e..4d4177ec802c 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -105,6 +105,7 @@
#define VM_EXIT_CLEAR_BNDCFGS 0x00800000
#define VM_EXIT_PT_CONCEAL_PIP 0x01000000
#define VM_EXIT_CLEAR_IA32_RTIT_CTL 0x02000000
+#define VM_EXIT_ACTIVATE_SECONDARY_CONTROLS 0x80000000

#define VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR 0x00036dff

@@ -247,6 +248,8 @@ enum vmcs_field {
TERTIARY_VM_EXEC_CONTROL_HIGH = 0x00002035,
PID_POINTER_TABLE = 0x00002042,
PID_POINTER_TABLE_HIGH = 0x00002043,
+ SECONDARY_VM_EXIT_CONTROLS = 0x00002044,
+ SECONDARY_VM_EXIT_CONTROLS_HIGH = 0x00002045,
GUEST_PHYSICAL_ADDRESS = 0x00002400,
GUEST_PHYSICAL_ADDRESS_HIGH = 0x00002401,
VMCS_LINK_POINTER = 0x00002800,
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index cb6588238f46..e8f3ad0f79ee 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -59,8 +59,9 @@ struct vmcs_config {
u32 cpu_based_exec_ctrl;
u32 cpu_based_2nd_exec_ctrl;
u64 cpu_based_3rd_exec_ctrl;
- u32 vmexit_ctrl;
u32 vmentry_ctrl;
+ u32 vmexit_ctrl;
+ u64 secondary_vmexit_ctrl;
u64 misc;
struct nested_vmx_msrs nested;
};
@@ -136,6 +137,12 @@ static inline bool cpu_has_tertiary_exec_ctrls(void)
CPU_BASED_ACTIVATE_TERTIARY_CONTROLS;
}

+static inline bool cpu_has_secondary_vmexit_ctrls(void)
+{
+ return vmcs_config.vmexit_ctrl &
+ VM_EXIT_ACTIVATE_SECONDARY_CONTROLS;
+}
+
static inline bool cpu_has_vmx_virtualize_apic_accesses(void)
{
return vmcs_config.cpu_based_2nd_exec_ctrl &
diff --git a/arch/x86/kvm/vmx/vmcs.h b/arch/x86/kvm/vmx/vmcs.h
index 7c1996b433e2..7d45a6504200 100644
--- a/arch/x86/kvm/vmx/vmcs.h
+++ b/arch/x86/kvm/vmx/vmcs.h
@@ -47,6 +47,7 @@ struct vmcs_host_state {
struct vmcs_controls_shadow {
u32 vm_entry;
u32 vm_exit;
+ u64 secondary_vm_exit;
u32 pin;
u32 exec;
u32 secondary_exec;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 396a806bf2b2..df769207cbe0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2574,6 +2574,7 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
u32 _cpu_based_2nd_exec_control = 0;
u64 _cpu_based_3rd_exec_control = 0;
u32 _vmexit_control = 0;
+ u64 _secondary_vmexit_control = 0;
u32 _vmentry_control = 0;
u64 basic_msr;
int i;
@@ -2693,6 +2694,11 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
_vmexit_control &= ~x_ctrl;
}

+ 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);
+
rdmsrl(MSR_IA32_VMX_BASIC, basic_msr);

/* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */
@@ -2714,8 +2720,9 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
vmcs_conf->cpu_based_exec_ctrl = _cpu_based_exec_control;
vmcs_conf->cpu_based_2nd_exec_ctrl = _cpu_based_2nd_exec_control;
vmcs_conf->cpu_based_3rd_exec_ctrl = _cpu_based_3rd_exec_control;
- vmcs_conf->vmexit_ctrl = _vmexit_control;
vmcs_conf->vmentry_ctrl = _vmentry_control;
+ vmcs_conf->vmexit_ctrl = _vmexit_control;
+ vmcs_conf->secondary_vmexit_ctrl = _secondary_vmexit_control;

rdmsrl(MSR_IA32_VMX_MISC, vmcs_conf->misc);

@@ -4420,9 +4427,21 @@ static u32 vmx_vmexit_ctrl(void)
if (cpu_has_perf_global_ctrl_bug())
vmexit_ctrl &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;

- /* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */
+ /*
+ * The following features are toggled dynamically:
+ * - Loading of PERF_GLOBAL_CTRL
+ * - Loading of EFER
+ * - Activating of SECONDARY_CONTROLS
+ */
return vmexit_ctrl &
- ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER);
+ ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL |
+ VM_EXIT_LOAD_IA32_EFER |
+ VM_EXIT_ACTIVATE_SECONDARY_CONTROLS);
+}
+
+static u64 vmx_secondary_vmexit_ctrl(void)
+{
+ return vmcs_config.secondary_vmexit_ctrl;
}

static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
@@ -4770,6 +4789,9 @@ static void init_vmcs(struct vcpu_vmx *vmx)

vm_exit_controls_set(vmx, vmx_vmexit_ctrl());

+ if (cpu_has_secondary_vmexit_ctrls())
+ secondary_vm_exit_controls_set(vmx, vmx_secondary_vmexit_ctrl());
+
/* 22.2.1, 20.8.1 */
vm_entry_controls_set(vmx, vmx_vmentry_ctrl());

diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index c2130d2c8e24..99a0f6783085 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -502,7 +502,11 @@ static inline u8 vmx_get_rvi(void)
VM_EXIT_LOAD_IA32_EFER | \
VM_EXIT_CLEAR_BNDCFGS | \
VM_EXIT_PT_CONCEAL_PIP | \
- VM_EXIT_CLEAR_IA32_RTIT_CTL)
+ VM_EXIT_CLEAR_IA32_RTIT_CTL | \
+ 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_REQUIRED_VMX_PIN_BASED_VM_EXEC_CONTROL \
(PIN_BASED_EXT_INTR_MASK | \
@@ -606,6 +610,7 @@ static __always_inline void lname##_controls_clearbit(struct vcpu_vmx *vmx, u##b
}
BUILD_CONTROLS_SHADOW(vm_entry, VM_ENTRY_CONTROLS, 32)
BUILD_CONTROLS_SHADOW(vm_exit, VM_EXIT_CONTROLS, 32)
+BUILD_CONTROLS_SHADOW(secondary_vm_exit, SECONDARY_VM_EXIT_CONTROLS, 64)
BUILD_CONTROLS_SHADOW(pin, PIN_BASED_VM_EXEC_CONTROL, 32)
BUILD_CONTROLS_SHADOW(exec, CPU_BASED_VM_EXEC_CONTROL, 32)
BUILD_CONTROLS_SHADOW(secondary_exec, SECONDARY_VM_EXEC_CONTROL, 32)
--
2.42.0