[RFC PATCH v2 67/69] KVM: TDX: add trace point for TDVMCALL and SEPT operation

From: isaku . yamahata
Date: Fri Jul 02 2021 - 18:08:24 EST


From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Signed-off-by: Yuan Yao <yuan.yao@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/kvm/trace.h | 58 +++++++++++++++++++++++++++++++++++++
arch/x86/kvm/vmx/tdx.c | 16 ++++++++++
arch/x86/kvm/vmx/tdx_arch.h | 9 ++++++
arch/x86/kvm/x86.c | 2 ++
4 files changed, 85 insertions(+)

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index c3398d0de9a7..58631124f08d 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -739,6 +739,64 @@ TRACE_EVENT(kvm_tdx_seamcall_exit,
__entry->r9, __entry->r10, __entry->r11)
);

+/*
+ * Tracepoint for TDVMCALL from a TDX guest
+ */
+TRACE_EVENT(kvm_tdvmcall,
+ TP_PROTO(struct kvm_vcpu *vcpu, __u32 exit_reason,
+ __u64 p1, __u64 p2, __u64 p3, __u64 p4),
+ TP_ARGS(vcpu, exit_reason, p1, p2, p3, p4),
+
+ TP_STRUCT__entry(
+ __field( __u64, rip )
+ __field( __u32, exit_reason )
+ __field( __u64, p1 )
+ __field( __u64, p2 )
+ __field( __u64, p3 )
+ __field( __u64, p4 )
+ ),
+
+ TP_fast_assign(
+ __entry->rip = kvm_rip_read(vcpu);
+ __entry->exit_reason = exit_reason;
+ __entry->p1 = p1;
+ __entry->p2 = p2;
+ __entry->p3 = p3;
+ __entry->p4 = p4;
+ ),
+
+ TP_printk("rip: %llx reason: %s p1: %llx p2: %llx p3: %llx p4: %llx",
+ __entry->rip,
+ __print_symbolic(__entry->exit_reason,
+ TDG_VP_VMCALL_EXIT_REASONS),
+ __entry->p1, __entry->p2, __entry->p3, __entry->p4)
+);
+
+/*
+ * Tracepoint for SEPT related SEAMCALLs.
+ */
+TRACE_EVENT(kvm_sept_seamcall,
+ TP_PROTO(__u64 op, __u64 gpa, __u64 hpa, int level),
+ TP_ARGS(op, gpa, hpa, level),
+
+ TP_STRUCT__entry(
+ __field( __u64, op )
+ __field( __u64, gpa )
+ __field( __u64, hpa )
+ __field( int, level )
+ ),
+
+ TP_fast_assign(
+ __entry->op = op;
+ __entry->gpa = gpa;
+ __entry->hpa = hpa;
+ __entry->level = level;
+ ),
+
+ TP_printk("op: %llu gpa: 0x%llx hpa: 0x%llx level: %u",
+ __entry->op, __entry->gpa, __entry->hpa, __entry->level)
+);
+
/*
* Tracepoint for nested #vmexit because of interrupt pending
*/
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 1aed4286ce0c..63130fb5a003 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -934,6 +934,10 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)

exit_reason = tdvmcall_exit_reason(vcpu);

+ trace_kvm_tdvmcall(vcpu, exit_reason,
+ tdvmcall_p1_read(vcpu), tdvmcall_p2_read(vcpu),
+ tdvmcall_p3_read(vcpu), tdvmcall_p4_read(vcpu));
+
switch (exit_reason) {
case EXIT_REASON_CPUID:
return tdx_emulate_cpuid(vcpu);
@@ -1011,11 +1015,15 @@ static void tdx_sept_set_private_spte(struct kvm_vcpu *vcpu, gfn_t gfn,

/* Build-time faults are induced and handled via TDH_MEM_PAGE_ADD. */
if (is_td_finalized(kvm_tdx)) {
+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_PAGE_AUG, gpa, hpa, level);
+
err = tdh_mem_page_aug(kvm_tdx->tdr.pa, gpa, hpa, &ex_ret);
SEPT_ERR(err, &ex_ret, TDH_MEM_PAGE_AUG, vcpu->kvm);
return;
}

+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_PAGE_ADD, gpa, hpa, level);
+
source_pa = kvm_tdx->source_pa & ~KVM_TDX_MEASURE_MEMORY_REGION;

err = tdh_mem_page_add(kvm_tdx->tdr.pa, gpa, hpa, source_pa, &ex_ret);
@@ -1039,6 +1047,8 @@ static void tdx_sept_drop_private_spte(struct kvm *kvm, gfn_t gfn, int level,
return;

if (is_hkid_assigned(kvm_tdx)) {
+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_PAGE_REMOVE, gpa, hpa, level);
+
err = tdh_mem_page_remove(kvm_tdx->tdr.pa, gpa, level, &ex_ret);
if (SEPT_ERR(err, &ex_ret, TDH_MEM_PAGE_REMOVE, kvm))
return;
@@ -1063,6 +1073,8 @@ static int tdx_sept_link_private_sp(struct kvm_vcpu *vcpu, gfn_t gfn,
struct tdx_ex_ret ex_ret;
u64 err;

+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_SEPT_ADD, gpa, hpa, level);
+
err = tdh_mem_spet_add(kvm_tdx->tdr.pa, gpa, level, hpa, &ex_ret);
if (SEPT_ERR(err, &ex_ret, TDH_MEM_SEPT_ADD, vcpu->kvm))
return -EIO;
@@ -1077,6 +1089,8 @@ static void tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn, int level)
struct tdx_ex_ret ex_ret;
u64 err;

+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_RANGE_BLOCK, gpa, -1ull, level);
+
err = tdh_mem_range_block(kvm_tdx->tdr.pa, gpa, level, &ex_ret);
SEPT_ERR(err, &ex_ret, TDH_MEM_RANGE_BLOCK, kvm);
}
@@ -1088,6 +1102,8 @@ static void tdx_sept_unzap_private_spte(struct kvm *kvm, gfn_t gfn, int level)
struct tdx_ex_ret ex_ret;
u64 err;

+ trace_kvm_sept_seamcall(SEAMCALL_TDH_MEM_RANGE_UNBLOCK, gpa, -1ull, level);
+
err = tdh_mem_range_unblock(kvm_tdx->tdr.pa, gpa, level, &ex_ret);
SEPT_ERR(err, &ex_ret, TDH_MEM_RANGE_UNBLOCK, kvm);
}
diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h
index 7258825b1e02..414b933a3b03 100644
--- a/arch/x86/kvm/vmx/tdx_arch.h
+++ b/arch/x86/kvm/vmx/tdx_arch.h
@@ -104,6 +104,15 @@
#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
#define TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT 0x10004

+#define TDG_VP_VMCALL_EXIT_REASONS \
+ { TDG_VP_VMCALL_GET_TD_VM_CALL_INFO, \
+ "GET_TD_VM_CALL_INFO" }, \
+ { TDG_VP_VMCALL_MAP_GPA, "MAP_GPA" }, \
+ { TDG_VP_VMCALL_GET_QUOTE, "GET_QUOTE" }, \
+ { TDG_VP_VMCALL_SETUP_EVENT_NOTIFY_INTERRUPT, \
+ "SETUP_EVENT_NOTIFY_INTERRUPT" }, \
+ VMX_EXIT_REASONS
+
/* TDX control structure (TDR/TDCS/TDVPS) field access codes */
#define TDX_CLASS_SHIFT 56
#define TDX_FIELD_MASK GENMASK_ULL(31, 0)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ba69abcc663a..ad619c1b2a88 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12104,6 +12104,8 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmrun);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit_inject);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_tdvmcall);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_sept_seamcall);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
--
2.25.1