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From:   Vitaly Kuznetsov <vkuznets@redhat.com>
To:     kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>
Cc:     Sean Christopherson <seanjc@google.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/4] KVM: nVMX: Invert 'unsupported by eVMCSv1' check
Date:   Tue, 18 Oct 2022 12:09:58 +0200
Message-Id: <20221018101000.934413-3-vkuznets@redhat.com>
In-Reply-To: <20221018101000.934413-1-vkuznets@redhat.com>
References: <20221018101000.934413-1-vkuznets@redhat.com>
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When a new feature gets implemented in KVM, EVMCS1_UNSUPPORTED_* defines
need to be adjusted to avoid the situation when the feature is exposed
to the guest but there's no corresponding eVMCS field[s] for it. This
is not obvious and fragile. Invert 'unsupported by eVMCSv1' check and
make it 'supported by eVMCSv1' instead, this way it's much harder to
make a mistake. New features will get added to EVMCS1_SUPPORTED_*
defines when the corresponding fields are added to eVMCS definition.

No functional change intended. EVMCS1_SUPPORTED_* defines are composed
by taking KVM_{REQUIRED,OPTIONAL}_VMX_ defines and filtering out what
was previously known as EVMCS1_UNSUPPORTED_*.

From all the controls, SECONDARY_EXEC_TSC_SCALING requires special
handling as it's actually present in eVMCSv1 definition but is not
currently supported for Hyper-V-on-KVM, just for KVM-on-Hyper-V. As
evmcs_supported_ctrls will be used for both scenarios, just add it
there instead of EVMCS1_SUPPORTED_2NDEXEC.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 arch/x86/kvm/vmx/evmcs.c | 42 +++++++++----------
 arch/x86/kvm/vmx/evmcs.h | 90 +++++++++++++++++++++++++++++++++-------
 2 files changed, 96 insertions(+), 36 deletions(-)

diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index 337783675731..0f031d27741a 100644
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -375,32 +375,32 @@ enum evmcs_ctrl_type {
 	NR_EVMCS_CTRLS,
 };
 
-static const u32 evmcs_unsupported_ctrls[NR_EVMCS_CTRLS][NR_EVMCS_REVISIONS] = {
+static const u32 evmcs_supported_ctrls[NR_EVMCS_CTRLS][NR_EVMCS_REVISIONS] = {
 	[EVMCS_EXIT_CTRLS] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_VMEXIT_CTRL,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_VMEXIT_CTRL,
 	},
 	[EVMCS_ENTRY_CTRLS] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_VMENTRY_CTRL,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_VMENTRY_CTRL,
 	},
 	[EVMCS_EXEC_CTRL] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_EXEC_CTRL,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_EXEC_CTRL,
 	},
 	[EVMCS_2NDEXEC] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_2NDEXEC,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_2NDEXEC & ~SECONDARY_EXEC_TSC_SCALING,
 	},
 	[EVMCS_PINCTRL] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_PINCTRL,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_PINCTRL,
 	},
 	[EVMCS_VMFUNC] = {
-		[EVMCSv1_LEGACY] = EVMCS1_UNSUPPORTED_VMFUNC,
+		[EVMCSv1_LEGACY] = EVMCS1_SUPPORTED_VMFUNC,
 	},
 };
 
-static u32 evmcs_get_unsupported_ctls(enum evmcs_ctrl_type ctrl_type)
+static u32 evmcs_get_supported_ctls(enum evmcs_ctrl_type ctrl_type)
 {
 	enum evmcs_revision evmcs_rev = EVMCSv1_LEGACY;
 
-	return evmcs_unsupported_ctrls[ctrl_type][evmcs_rev];
+	return evmcs_supported_ctrls[ctrl_type][evmcs_rev];
 }
 
 static bool evmcs_has_perf_global_ctrl(struct kvm_vcpu *vcpu)
@@ -424,7 +424,7 @@ void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *
 {
 	u32 ctl_low = (u32)*pdata;
 	u32 ctl_high = (u32)(*pdata >> 32);
-	u32 unsupported_ctrls;
+	u32 supported_ctrls;
 
 	/*
 	 * Hyper-V 2016 and 2019 try using these features even when eVMCS
@@ -433,31 +433,31 @@ void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *
 	switch (msr_index) {
 	case MSR_IA32_VMX_EXIT_CTLS:
 	case MSR_IA32_VMX_TRUE_EXIT_CTLS:
-		unsupported_ctrls = evmcs_get_unsupported_ctls(EVMCS_EXIT_CTRLS);
+		supported_ctrls = evmcs_get_supported_ctls(EVMCS_EXIT_CTRLS);
 		if (!evmcs_has_perf_global_ctrl(vcpu))
-			unsupported_ctrls |= VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;
-		ctl_high &= ~unsupported_ctrls;
+			supported_ctrls &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL;
+		ctl_high &= supported_ctrls;
 		break;
 	case MSR_IA32_VMX_ENTRY_CTLS:
 	case MSR_IA32_VMX_TRUE_ENTRY_CTLS:
-		unsupported_ctrls = evmcs_get_unsupported_ctls(EVMCS_ENTRY_CTRLS);
+		supported_ctrls = evmcs_get_supported_ctls(EVMCS_ENTRY_CTRLS);
 		if (!evmcs_has_perf_global_ctrl(vcpu))
-			unsupported_ctrls |= VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL;
-		ctl_high &= ~unsupported_ctrls;
+			supported_ctrls &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL;
+		ctl_high &= supported_ctrls;
 		break;
 	case MSR_IA32_VMX_PROCBASED_CTLS:
 	case MSR_IA32_VMX_TRUE_PROCBASED_CTLS:
-		ctl_high &= ~evmcs_get_unsupported_ctls(EVMCS_EXEC_CTRL);
+		ctl_high &= evmcs_get_supported_ctls(EVMCS_EXEC_CTRL);
 		break;
 	case MSR_IA32_VMX_PROCBASED_CTLS2:
-		ctl_high &= ~evmcs_get_unsupported_ctls(EVMCS_2NDEXEC);
+		ctl_high &= evmcs_get_supported_ctls(EVMCS_2NDEXEC);
 		break;
 	case MSR_IA32_VMX_TRUE_PINBASED_CTLS:
 	case MSR_IA32_VMX_PINBASED_CTLS:
-		ctl_high &= ~evmcs_get_unsupported_ctls(EVMCS_PINCTRL);
+		ctl_high &= evmcs_get_supported_ctls(EVMCS_PINCTRL);
 		break;
 	case MSR_IA32_VMX_VMFUNC:
-		ctl_low &= ~evmcs_get_unsupported_ctls(EVMCS_VMFUNC);
+		ctl_low &= evmcs_get_supported_ctls(EVMCS_VMFUNC);
 		break;
 	}
 
@@ -467,7 +467,7 @@ void nested_evmcs_filter_control_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *
 static bool nested_evmcs_is_valid_controls(enum evmcs_ctrl_type ctrl_type,
 					   u32 val)
 {
-	return !(val & evmcs_get_unsupported_ctls(ctrl_type));
+	return !(val & ~evmcs_get_supported_ctls(ctrl_type));
 }
 
 int nested_evmcs_check_controls(struct vmcs12 *vmcs12)
diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h
index 6f746ef3c038..4c351f334446 100644
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/evmcs.h
@@ -46,22 +46,82 @@ DECLARE_STATIC_KEY_FALSE(enable_evmcs);
  * Currently unsupported in KVM:
  *	GUEST_IA32_RTIT_CTL		= 0x00002814,
  */
-#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 |			\
-	 SECONDARY_EXEC_APIC_REGISTER_VIRT |				\
-	 SECONDARY_EXEC_ENABLE_PML |					\
-	 SECONDARY_EXEC_ENABLE_VMFUNC |					\
-	 SECONDARY_EXEC_SHADOW_VMCS |					\
+#define EVMCS1_SUPPORTED_PINCTRL					\
+	(PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR |				\
+	 PIN_BASED_EXT_INTR_MASK |					\
+	 PIN_BASED_NMI_EXITING |					\
+	 PIN_BASED_VIRTUAL_NMIS)
+
+#define EVMCS1_SUPPORTED_EXEC_CTRL					\
+	(CPU_BASED_ALWAYSON_WITHOUT_TRUE_MSR |				\
+	 CPU_BASED_HLT_EXITING |					\
+	 CPU_BASED_CR3_LOAD_EXITING |					\
+	 CPU_BASED_CR3_STORE_EXITING |					\
+	 CPU_BASED_UNCOND_IO_EXITING |					\
+	 CPU_BASED_MOV_DR_EXITING |					\
+	 CPU_BASED_USE_TSC_OFFSETTING |					\
+	 CPU_BASED_MWAIT_EXITING |					\
+	 CPU_BASED_MONITOR_EXITING |					\
+	 CPU_BASED_INVLPG_EXITING |					\
+	 CPU_BASED_RDPMC_EXITING |					\
+	 CPU_BASED_INTR_WINDOW_EXITING |				\
+	 CPU_BASED_CR8_LOAD_EXITING |					\
+	 CPU_BASED_CR8_STORE_EXITING |					\
+	 CPU_BASED_RDTSC_EXITING |					\
+	 CPU_BASED_TPR_SHADOW |						\
+	 CPU_BASED_USE_IO_BITMAPS |					\
+	 CPU_BASED_MONITOR_TRAP_FLAG |					\
+	 CPU_BASED_USE_MSR_BITMAPS |					\
+	 CPU_BASED_NMI_WINDOW_EXITING |					\
+	 CPU_BASED_PAUSE_EXITING |					\
+	 CPU_BASED_ACTIVATE_SECONDARY_CONTROLS)
+
+#define EVMCS1_SUPPORTED_2NDEXEC					\
+	(SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |			\
+	 SECONDARY_EXEC_WBINVD_EXITING |				\
+	 SECONDARY_EXEC_ENABLE_VPID |					\
+	 SECONDARY_EXEC_ENABLE_EPT |					\
+	 SECONDARY_EXEC_UNRESTRICTED_GUEST |				\
+	 SECONDARY_EXEC_DESC |						\
+	 SECONDARY_EXEC_ENABLE_RDTSCP |					\
+	 SECONDARY_EXEC_ENABLE_INVPCID |				\
+	 SECONDARY_EXEC_XSAVES |					\
+	 SECONDARY_EXEC_RDSEED_EXITING |				\
+	 SECONDARY_EXEC_RDRAND_EXITING |				\
 	 SECONDARY_EXEC_TSC_SCALING |					\
-	 SECONDARY_EXEC_PAUSE_LOOP_EXITING)
-#define EVMCS1_UNSUPPORTED_VMEXIT_CTRL					\
-	(VM_EXIT_SAVE_VMX_PREEMPTION_TIMER)
-#define EVMCS1_UNSUPPORTED_VMENTRY_CTRL (0)
-#define EVMCS1_UNSUPPORTED_VMFUNC (VMX_VMFUNC_EPTP_SWITCHING)
+	 SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE |				\
+	 SECONDARY_EXEC_PT_USE_GPA |					\
+	 SECONDARY_EXEC_PT_CONCEAL_VMX |				\
+	 SECONDARY_EXEC_BUS_LOCK_DETECTION |				\
+	 SECONDARY_EXEC_NOTIFY_VM_EXITING |				\
+	 SECONDARY_EXEC_ENCLS_EXITING)
+
+#define EVMCS1_SUPPORTED_VMEXIT_CTRL					\
+	(VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR |				\
+	 VM_EXIT_SAVE_DEBUG_CONTROLS |					\
+	 VM_EXIT_ACK_INTR_ON_EXIT |					\
+	 VM_EXIT_HOST_ADDR_SPACE_SIZE |					\
+	 VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL |				\
+	 VM_EXIT_SAVE_IA32_PAT |					\
+	 VM_EXIT_LOAD_IA32_PAT |					\
+	 VM_EXIT_SAVE_IA32_EFER |					\
+	 VM_EXIT_LOAD_IA32_EFER |					\
+	 VM_EXIT_CLEAR_BNDCFGS |					\
+	 VM_EXIT_PT_CONCEAL_PIP |					\
+	 VM_EXIT_CLEAR_IA32_RTIT_CTL)
+
+#define EVMCS1_SUPPORTED_VMENTRY_CTRL					\
+	(VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR |				\
+	 VM_ENTRY_LOAD_DEBUG_CONTROLS |					\
+	 VM_ENTRY_IA32E_MODE |						\
+	 VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL |				\
+	 VM_ENTRY_LOAD_IA32_PAT |					\
+	 VM_ENTRY_LOAD_IA32_EFER |					\
+	 VM_ENTRY_LOAD_BNDCFGS |					\
+	 VM_ENTRY_PT_CONCEAL_PIP |					\
+	 VM_ENTRY_LOAD_IA32_RTIT_CTL)
+
+#define EVMCS1_SUPPORTED_VMFUNC (0)
 
 struct evmcs_field {
 	u16 offset;
-- 
2.37.3