Commit 2ef7619d authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
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KVM: VMX: Add helpers to query Intel PT mode 



Add helpers to query which of the (two) supported PT modes is active.
The primary motivation is to help document that there is a third PT mode
(host-only) that's currently not supported by KVM.  As is, it's not
obvious that PT_MODE_SYSTEM != !PT_MODE_HOST_GUEST and vice versa, e.g.
that "pt_mode == PT_MODE_SYSTEM" and "pt_mode != PT_MODE_HOST_GUEST" are
two distinct checks.

No functional change intended.

Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 0eee8f9d

arch/x86/kvm/vmx/capabilities.h

+18 −0
Original line number Diff line number Diff line
@@ -354,4 +354,22 @@ static inline bool cpu_has_vmx_intel_pt(void) 
		(vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_RTIT_CTL);

}



/*

 * Processor Trace can operate in one of three modes:

 *  a. system-wide: trace both host/guest and output to host buffer

 *  b. host-only:   only trace host and output to host buffer

 *  c. host-guest:  trace host and guest simultaneously and output to their

 *                  respective buffer

 *

 * KVM currently only supports (a) and (c).

 */

static inline bool vmx_pt_mode_is_system(void)

{

	return pt_mode == PT_MODE_SYSTEM;

}

static inline bool vmx_pt_mode_is_host_guest(void)

{

	return pt_mode == PT_MODE_HOST_GUEST;

}



#endif /* __KVM_X86_VMX_CAPS_H */

arch/x86/kvm/vmx/nested.c

+1 −1
Original line number Diff line number Diff line
@@ -4602,7 +4602,7 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu) 
	vmx->nested.vmcs02_initialized = false;

	vmx->nested.vmxon = true;



	if (pt_mode == PT_MODE_HOST_GUEST) {

	if (vmx_pt_mode_is_host_guest()) {

		vmx->pt_desc.guest.ctl = 0;

		pt_update_intercept_for_msr(vmx);

	}

arch/x86/kvm/vmx/vmx.c

+13 −13
Original line number Diff line number Diff line
@@ -1059,7 +1059,7 @@ static unsigned long segment_base(u16 selector) 


static inline bool pt_can_write_msr(struct vcpu_vmx *vmx)

{

	return (pt_mode == PT_MODE_HOST_GUEST) &&

	return vmx_pt_mode_is_host_guest() &&

	       !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);

}
@@ -1093,7 +1093,7 @@ static inline void pt_save_msr(struct pt_ctx *ctx, u32 addr_range) 


static void pt_guest_enter(struct vcpu_vmx *vmx)

{

	if (pt_mode == PT_MODE_SYSTEM)

	if (vmx_pt_mode_is_system())

		return;



	/*
@@ -1110,7 +1110,7 @@ static void pt_guest_enter(struct vcpu_vmx *vmx) 


static void pt_guest_exit(struct vcpu_vmx *vmx)

{

	if (pt_mode == PT_MODE_SYSTEM)

	if (vmx_pt_mode_is_system())

		return;



	if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) {
@@ -1904,24 +1904,24 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
							&msr_info->data);

		break;

	case MSR_IA32_RTIT_CTL:

		if (pt_mode != PT_MODE_HOST_GUEST)

		if (!vmx_pt_mode_is_host_guest())

			return 1;

		msr_info->data = vmx->pt_desc.guest.ctl;

		break;

	case MSR_IA32_RTIT_STATUS:

		if (pt_mode != PT_MODE_HOST_GUEST)

		if (!vmx_pt_mode_is_host_guest())

			return 1;

		msr_info->data = vmx->pt_desc.guest.status;

		break;

	case MSR_IA32_RTIT_CR3_MATCH:

		if ((pt_mode != PT_MODE_HOST_GUEST) ||

		if (!vmx_pt_mode_is_host_guest() ||

			!intel_pt_validate_cap(vmx->pt_desc.caps,

						PT_CAP_cr3_filtering))

			return 1;

		msr_info->data = vmx->pt_desc.guest.cr3_match;

		break;

	case MSR_IA32_RTIT_OUTPUT_BASE:

		if ((pt_mode != PT_MODE_HOST_GUEST) ||

		if (!vmx_pt_mode_is_host_guest() ||

			(!intel_pt_validate_cap(vmx->pt_desc.caps,

					PT_CAP_topa_output) &&

			 !intel_pt_validate_cap(vmx->pt_desc.caps,
@@ -1930,7 +1930,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
		msr_info->data = vmx->pt_desc.guest.output_base;

		break;

	case MSR_IA32_RTIT_OUTPUT_MASK:

		if ((pt_mode != PT_MODE_HOST_GUEST) ||

		if (!vmx_pt_mode_is_host_guest() ||

			(!intel_pt_validate_cap(vmx->pt_desc.caps,

					PT_CAP_topa_output) &&

			 !intel_pt_validate_cap(vmx->pt_desc.caps,
@@ -1940,7 +1940,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
		break;

	case MSR_IA32_RTIT_ADDR0_A ... MSR_IA32_RTIT_ADDR3_B:

		index = msr_info->index - MSR_IA32_RTIT_ADDR0_A;

		if ((pt_mode != PT_MODE_HOST_GUEST) ||

		if (!vmx_pt_mode_is_host_guest() ||

			(index >= 2 * intel_pt_validate_cap(vmx->pt_desc.caps,

					PT_CAP_num_address_ranges)))

			return 1;
@@ -2146,7 +2146,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
			return 1;

		return vmx_set_vmx_msr(vcpu, msr_index, data);

	case MSR_IA32_RTIT_CTL:

		if ((pt_mode != PT_MODE_HOST_GUEST) ||

		if (!vmx_pt_mode_is_host_guest() ||

			vmx_rtit_ctl_check(vcpu, data) ||

			vmx->nested.vmxon)

			return 1;
@@ -4023,7 +4023,7 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx) 


	u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;



	if (pt_mode == PT_MODE_SYSTEM)

	if (vmx_pt_mode_is_system())

		exec_control &= ~(SECONDARY_EXEC_PT_USE_GPA | SECONDARY_EXEC_PT_CONCEAL_VMX);

	if (!cpu_need_virtualize_apic_accesses(vcpu))

		exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
@@ -4264,7 +4264,7 @@ static void init_vmcs(struct vcpu_vmx *vmx) 
	if (cpu_has_vmx_encls_vmexit())

		vmcs_write64(ENCLS_EXITING_BITMAP, -1ull);



	if (pt_mode == PT_MODE_HOST_GUEST) {

	if (vmx_pt_mode_is_host_guest()) {

		memset(&vmx->pt_desc, 0, sizeof(vmx->pt_desc));

		/* Bit[6~0] are forced to 1, writes are ignored. */

		vmx->pt_desc.guest.output_mask = 0x7F;
@@ -6318,7 +6318,7 @@ static bool vmx_has_emulated_msr(int index) 


static bool vmx_pt_supported(void)

{

	return pt_mode == PT_MODE_HOST_GUEST;

	return vmx_pt_mode_is_host_guest();

}



static void vmx_recover_nmi_blocking(struct vcpu_vmx *vmx)

arch/x86/kvm/vmx/vmx.h

+2 −2
Original line number Diff line number Diff line
@@ -452,7 +452,7 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx) 
static inline u32 vmx_vmentry_ctrl(void)

{

	u32 vmentry_ctrl = vmcs_config.vmentry_ctrl;

	if (pt_mode == PT_MODE_SYSTEM)

	if (vmx_pt_mode_is_system())

		vmentry_ctrl &= ~(VM_ENTRY_PT_CONCEAL_PIP |

				  VM_ENTRY_LOAD_IA32_RTIT_CTL);

	/* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */
@@ -463,7 +463,7 @@ static inline u32 vmx_vmentry_ctrl(void) 
static inline u32 vmx_vmexit_ctrl(void)

{

	u32 vmexit_ctrl = vmcs_config.vmexit_ctrl;

	if (pt_mode == PT_MODE_SYSTEM)

	if (vmx_pt_mode_is_system())

		vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP |

				 VM_EXIT_CLEAR_IA32_RTIT_CTL);

	/* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */

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