[PATCH v4 3/6] KVM: VMX: Detect Tertiary VM-Execution control when setup VMCS config

From: Zeng Guang
Date: Sun Aug 08 2021 - 23:54:51 EST


From: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>

Check VMX feature on tertiary execution control in VMCS config setup.
Currently it's not supported for hyper-v and disabled for now.

Signed-off-by: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>
Signed-off-by: Zeng Guang <guang.zeng@xxxxxxxxx>
---
arch/x86/include/asm/vmx.h | 3 +++
arch/x86/kvm/vmx/capabilities.h | 7 ++++++
arch/x86/kvm/vmx/evmcs.c | 2 ++
arch/x86/kvm/vmx/evmcs.h | 1 +
arch/x86/kvm/vmx/vmcs.h | 1 +
arch/x86/kvm/vmx/vmx.c | 40 ++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/vmx.h | 1 +
7 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 0ffaa3156a4e..8c929596a299 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -31,6 +31,7 @@
#define CPU_BASED_RDTSC_EXITING VMCS_CONTROL_BIT(RDTSC_EXITING)
#define CPU_BASED_CR3_LOAD_EXITING VMCS_CONTROL_BIT(CR3_LOAD_EXITING)
#define CPU_BASED_CR3_STORE_EXITING VMCS_CONTROL_BIT(CR3_STORE_EXITING)
+#define CPU_BASED_ACTIVATE_TERTIARY_CONTROLS VMCS_CONTROL_BIT(TERTIARY_CONTROLS)
#define CPU_BASED_CR8_LOAD_EXITING VMCS_CONTROL_BIT(CR8_LOAD_EXITING)
#define CPU_BASED_CR8_STORE_EXITING VMCS_CONTROL_BIT(CR8_STORE_EXITING)
#define CPU_BASED_TPR_SHADOW VMCS_CONTROL_BIT(VIRTUAL_TPR)
@@ -221,6 +222,8 @@ enum vmcs_field {
ENCLS_EXITING_BITMAP_HIGH = 0x0000202F,
TSC_MULTIPLIER = 0x00002032,
TSC_MULTIPLIER_HIGH = 0x00002033,
+ TERTIARY_VM_EXEC_CONTROL = 0x00002034,
+ TERTIARY_VM_EXEC_CONTROL_HIGH = 0x00002035,
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 4705ad55abb5..38d414f64e61 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -59,6 +59,7 @@ struct vmcs_config {
u32 pin_based_exec_ctrl;
u32 cpu_based_exec_ctrl;
u32 cpu_based_2nd_exec_ctrl;
+ u64 cpu_based_3rd_exec_ctrl;
u32 vmexit_ctrl;
u32 vmentry_ctrl;
struct nested_vmx_msrs nested;
@@ -131,6 +132,12 @@ static inline bool cpu_has_secondary_exec_ctrls(void)
CPU_BASED_ACTIVATE_SECONDARY_CONTROLS;
}

+static inline bool cpu_has_tertiary_exec_ctrls(void)
+{
+ return vmcs_config.cpu_based_exec_ctrl &
+ CPU_BASED_ACTIVATE_TERTIARY_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/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index 896b2a50b4aa..03c15e1e5807 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -299,8 +299,10 @@ const unsigned int nr_evmcs_1_fields = ARRAY_SIZE(vmcs_field_to_evmcs_1);

__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf)
{
+ vmcs_conf->cpu_based_exec_ctrl &= ~EVMCS1_UNSUPPORTED_EXEC_CTRL;
vmcs_conf->pin_based_exec_ctrl &= ~EVMCS1_UNSUPPORTED_PINCTRL;
vmcs_conf->cpu_based_2nd_exec_ctrl &= ~EVMCS1_UNSUPPORTED_2NDEXEC;
+ vmcs_conf->cpu_based_3rd_exec_ctrl = 0;

vmcs_conf->vmexit_ctrl &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL;
vmcs_conf->vmentry_ctrl &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL;
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h
index 2ec9b46f0d0c..8a20295f4f0f 100644
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/evmcs.h
@@ -50,6 +50,7 @@ DECLARE_STATIC_KEY_FALSE(enable_evmcs);
*/
#define EVMCS1_UNSUPPORTED_PINCTRL (PIN_BASED_POSTED_INTR | \
PIN_BASED_VMX_PREEMPTION_TIMER)
+#define EVMCS1_UNSUPPORTED_EXEC_CTRL (CPU_BASED_ACTIVATE_TERTIARY_CONTROLS)
#define EVMCS1_UNSUPPORTED_2NDEXEC \
(SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY | \
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES | \
diff --git a/arch/x86/kvm/vmx/vmcs.h b/arch/x86/kvm/vmx/vmcs.h
index 4b9957e2bf5b..83e2065a955d 100644
--- a/arch/x86/kvm/vmx/vmcs.h
+++ b/arch/x86/kvm/vmx/vmcs.h
@@ -48,6 +48,7 @@ struct vmcs_controls_shadow {
u32 pin;
u32 exec;
u32 secondary_exec;
+ u64 tertiary_exec;
};

/*
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 927a552393b9..ee8c5664dc95 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2391,6 +2391,23 @@ static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
return 0;
}

+static __init int adjust_vmx_controls_64(u64 ctl_min, u64 ctl_opt,
+ u32 msr, u64 *result)
+{
+ u64 vmx_msr;
+ u64 ctl = ctl_min | ctl_opt;
+
+ rdmsrl(msr, vmx_msr);
+ ctl &= vmx_msr; /* bit == 1 means it can be set */
+
+ /* Ensure minimum (required) set of control bits are supported. */
+ if (ctl_min & ~ctl)
+ return -EIO;
+
+ *result = ctl;
+ return 0;
+}
+
static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
struct vmx_capability *vmx_cap)
{
@@ -2399,6 +2416,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
u32 _pin_based_exec_control = 0;
u32 _cpu_based_exec_control = 0;
u32 _cpu_based_2nd_exec_control = 0;
+ u64 _cpu_based_3rd_exec_control = 0;
u32 _vmexit_control = 0;
u32 _vmentry_control = 0;

@@ -2420,7 +2438,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,

opt = CPU_BASED_TPR_SHADOW |
CPU_BASED_USE_MSR_BITMAPS |
- CPU_BASED_ACTIVATE_SECONDARY_CONTROLS;
+ CPU_BASED_ACTIVATE_SECONDARY_CONTROLS |
+ CPU_BASED_ACTIVATE_TERTIARY_CONTROLS;
if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_PROCBASED_CTLS,
&_cpu_based_exec_control) < 0)
return -EIO;
@@ -2494,6 +2513,16 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
"1-setting enable VPID VM-execution control\n");
}

+ if (_cpu_based_exec_control & CPU_BASED_ACTIVATE_TERTIARY_CONTROLS) {
+ u64 opt3 = 0;
+ u64 min3 = 0;
+
+ if (adjust_vmx_controls_64(min3, opt3,
+ MSR_IA32_VMX_PROCBASED_CTLS3,
+ &_cpu_based_3rd_exec_control))
+ return -EIO;
+ }
+
min = VM_EXIT_SAVE_DEBUG_CONTROLS | VM_EXIT_ACK_INTR_ON_EXIT;
#ifdef CONFIG_X86_64
min |= VM_EXIT_HOST_ADDR_SPACE_SIZE;
@@ -2581,6 +2610,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
vmcs_conf->pin_based_exec_ctrl = _pin_based_exec_control;
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;

@@ -4148,6 +4178,11 @@ u32 vmx_exec_control(struct vcpu_vmx *vmx)
return exec_control;
}

+static u64 vmx_tertiary_exec_control(struct vcpu_vmx *vmx)
+{
+ return vmcs_config.cpu_based_3rd_exec_ctrl;
+}
+
/*
* Adjust a single secondary execution control bit to intercept/allow an
* instruction in the guest. This is usually done based on whether or not a
@@ -4319,6 +4354,9 @@ static void init_vmcs(struct vcpu_vmx *vmx)
secondary_exec_controls_set(vmx, vmx->secondary_exec_control);
}

+ if (cpu_has_tertiary_exec_ctrls())
+ tertiary_exec_controls_set(vmx, vmx_tertiary_exec_control(vmx));
+
if (kvm_vcpu_apicv_active(&vmx->vcpu)) {
vmcs_write64(EOI_EXIT_BITMAP0, 0);
vmcs_write64(EOI_EXIT_BITMAP1, 0);
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 558f61208a6f..f19ef1e14d08 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -441,6 +441,7 @@ BUILD_CONTROLS_SHADOW(vm_exit, VM_EXIT_CONTROLS, 32)
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)
+BUILD_CONTROLS_SHADOW(tertiary_exec, TERTIARY_VM_EXEC_CONTROL, 64)

static inline void vmx_register_cache_reset(struct kvm_vcpu *vcpu)
{
--
2.25.1