Commit 96d6955d authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: nVMX: Invert 'unsupported by eVMCSv1' check 



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: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20221104144708.435865-3-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a2ad080b

arch/x86/kvm/vmx/hyperv.c

+21 −21
Original line number Diff line number Diff line
@@ -368,32 +368,32 @@ 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)
@@ -417,7 +417,7 @@ 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
@@ -426,31 +426,31 @@ 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;

	}
@@ -460,7 +460,7 @@ 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)

arch/x86/kvm/vmx/hyperv.h

+75 −15
Original line number Diff line number Diff line
@@ -48,22 +48,82 @@ 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;