From: Nicușor Cîțu <ncitu@xxxxxxxxxxxxxxx>
This patch introduces additional tracepoints that are meant to help
in following the flow of interrupts and exceptions queued to a guest
VM. At the same time the kvm_exit tracepoint is enhanced with the
vCPU ID.
One scenario in which these help is debugging lost interrupts due to
a buggy VMEXIT handler.
Signed-off-by: Nicușor Cîțu <ncitu@xxxxxxxxxxxxxxx>
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
arch/x86/kvm/svm.c | 9 +++-
arch/x86/kvm/trace.h | 118 ++++++++++++++++++++++++++++++++---------
arch/x86/kvm/vmx/vmx.c | 8 ++-
arch/x86/kvm/x86.c | 12 +++--
4 files changed, 116 insertions(+), 31 deletions(-)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index cb536a2611f6..00bdf885f9a4 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -799,6 +799,8 @@ static void svm_queue_exception(struct kvm_vcpu *vcpu)
bool reinject = vcpu->arch.exception.injected;
u32 error_code = vcpu->arch.exception.error_code;
+ trace_kvm_inj_exception(vcpu);
+
/*
* If we are within a nested VM we'd better #VMEXIT and let the guest
* handle the exception
@@ -5108,6 +5110,8 @@ static void svm_inject_nmi(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
+ trace_kvm_inj_nmi(vcpu);
+
svm->vmcb->control.event_inj = SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_NMI;
vcpu->arch.hflags |= HF_NMI_MASK;
set_intercept(svm, INTERCEPT_IRET);
@@ -5133,7 +5137,8 @@ static void svm_set_irq(struct kvm_vcpu *vcpu)
BUG_ON(!(gif_set(svm)));
- trace_kvm_inj_virq(vcpu->arch.interrupt.nr);
+ trace_kvm_inj_interrupt(vcpu);
+
++vcpu->stat.irq_injections;
svm->vmcb->control.event_inj = vcpu->arch.interrupt.nr |
@@ -5637,6 +5642,8 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu)
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb_control_area *control = &svm->vmcb->control;
+ trace_kvm_cancel_inj(vcpu);
+
control->exit_int_info = control->event_inj;
control->exit_int_info_err = control->event_inj_err;
control->event_inj = 0;
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 6432d08c7de7..cb47889ddc2c 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -227,6 +227,7 @@ TRACE_EVENT(kvm_exit,
TP_ARGS(exit_reason, vcpu, isa),
TP_STRUCT__entry(
+ __field( unsigned int, vcpu_id )
__field( unsigned int, exit_reason )
__field( unsigned long, guest_rip )
__field( u32, isa )
@@ -235,6 +236,7 @@ TRACE_EVENT(kvm_exit,
),
TP_fast_assign(
+ __entry->vcpu_id = vcpu->vcpu_id;
__entry->exit_reason = exit_reason;
__entry->guest_rip = kvm_rip_read(vcpu);
__entry->isa = isa;
@@ -242,7 +244,8 @@ TRACE_EVENT(kvm_exit,
&__entry->info2);
),
- TP_printk("reason %s rip 0x%lx info %llx %llx",
+ TP_printk("vcpu %u reason %s rip 0x%lx info %llx %llx",
+ __entry->vcpu_id,
(__entry->isa == KVM_ISA_VMX) ?
__print_symbolic(__entry->exit_reason, VMX_EXIT_REASONS) :
__print_symbolic(__entry->exit_reason, SVM_EXIT_REASONS),
@@ -252,19 +255,38 @@ TRACE_EVENT(kvm_exit,
/*
* Tracepoint for kvm interrupt injection:
*/
-TRACE_EVENT(kvm_inj_virq,
- TP_PROTO(unsigned int irq),
- TP_ARGS(irq),
-
+TRACE_EVENT(kvm_inj_interrupt,
+ TP_PROTO(struct kvm_vcpu *vcpu),
+ TP_ARGS(vcpu),
TP_STRUCT__entry(
- __field( unsigned int, irq )
+ __field(__u32, vcpu_id)
+ __field(__u32, nr)
),
-
TP_fast_assign(
- __entry->irq = irq;
+ __entry->vcpu_id = vcpu->vcpu_id;
+ __entry->nr = vcpu->arch.interrupt.nr;
),
+ TP_printk("vcpu %u irq %u",
+ __entry->vcpu_id,
+ __entry->nr
+ )
+);
- TP_printk("irq %u", __entry->irq)
+/*
+ * Tracepoint for kvm nmi injection:
+ */
+TRACE_EVENT(kvm_inj_nmi,
+ TP_PROTO(struct kvm_vcpu *vcpu),
+ TP_ARGS(vcpu),
+ TP_STRUCT__entry(
+ __field(__u32, vcpu_id)
+ ),
+ TP_fast_assign(
+ __entry->vcpu_id = vcpu->vcpu_id;
+ ),
+ TP_printk("vcpu %u",
+ __entry->vcpu_id
+ )
);
#define EXS(x) { x##_VECTOR, "#" #x }
@@ -275,28 +297,76 @@ TRACE_EVENT(kvm_inj_virq,
EXS(MF), EXS(AC), EXS(MC)
/*
- * Tracepoint for kvm interrupt injection:
+ * Tracepoint for kvm exception injection:
*/
-TRACE_EVENT(kvm_inj_exception,
- TP_PROTO(unsigned exception, bool has_error, unsigned error_code),
- TP_ARGS(exception, has_error, error_code),
-
+TRACE_EVENT(
+ kvm_inj_exception,
+ TP_PROTO(struct kvm_vcpu *vcpu),
+ TP_ARGS(vcpu),
TP_STRUCT__entry(
- __field( u8, exception )
- __field( u8, has_error )
- __field( u32, error_code )
+ __field(__u32, vcpu_id)
+ __field(__u8, nr)
+ __field(__u64, address)
+ __field(__u16, error_code)
+ __field(bool, has_error_code)
),
+ TP_fast_assign(
+ __entry->vcpu_id = vcpu->vcpu_id;
+ __entry->nr = vcpu->arch.exception.nr;
+ __entry->address = vcpu->arch.exception.nested_apf ?
+ vcpu->arch.apf.nested_apf_token : vcpu->arch.cr2;
+ __entry->error_code = vcpu->arch.exception.error_code;
+ __entry->has_error_code = vcpu->arch.exception.has_error_code;
+ ),
+ TP_printk("vcpu %u %s address %llx error %x",
+ __entry->vcpu_id,
+ __print_symbolic(__entry->nr, kvm_trace_sym_exc),
+ __entry->nr == PF_VECTOR ? __entry->address : 0,
+ __entry->has_error_code ? __entry->error_code : 0
+ )
+);
+TRACE_EVENT(
+ kvm_inj_emul_exception,
+ TP_PROTO(struct kvm_vcpu *vcpu, struct x86_exception *fault),
+ TP_ARGS(vcpu, fault),
+ TP_STRUCT__entry(
+ __field(__u32, vcpu_id)
+ __field(__u8, vector)
+ __field(__u64, address)
+ __field(__u16, error_code)
+ __field(bool, error_code_valid)
+ ),
TP_fast_assign(
- __entry->exception = exception;
- __entry->has_error = has_error;
- __entry->error_code = error_code;
+ __entry->vcpu_id = vcpu->vcpu_id;
+ __entry->vector = fault->vector;
+ __entry->address = fault->address;
+ __entry->error_code = fault->error_code;
+ __entry->error_code_valid = fault->error_code_valid;
),
+ TP_printk("vcpu %u %s address %llx error %x",
+ __entry->vcpu_id,
+ __print_symbolic(__entry->vector, kvm_trace_sym_exc),
+ __entry->vector == PF_VECTOR ? __entry->address : 0,
+ __entry->error_code_valid ? __entry->error_code : 0
+ )
+);
- TP_printk("%s (0x%x)",
- __print_symbolic(__entry->exception, kvm_trace_sym_exc),
- /* FIXME: don't print error_code if not present */
- __entry->has_error ? __entry->error_code : 0)
+/*
+ * Tracepoint for kvm cancel injection:
+ */
+TRACE_EVENT(kvm_cancel_inj,
+ TP_PROTO(struct kvm_vcpu *vcpu),
+ TP_ARGS(vcpu),
+ TP_STRUCT__entry(
+ __field(__u32, vcpu_id)
+ ),
+ TP_fast_assign(
+ __entry->vcpu_id = vcpu->vcpu_id;
+ ),
+ TP_printk("vcpu %u",
+ __entry->vcpu_id
+ )
);
/*
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 152c58b63f69..85561994661a 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -1494,6 +1494,8 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu)
u32 error_code = vcpu->arch.exception.error_code;
u32 intr_info = nr | INTR_INFO_VALID_MASK;
+ trace_kvm_inj_exception(vcpu);
+
kvm_deliver_exception_payload(vcpu);
if (has_error_code) {
@@ -4266,7 +4268,7 @@ static void vmx_inject_irq(struct kvm_vcpu *vcpu)
uint32_t intr;
int irq = vcpu->arch.interrupt.nr;
- trace_kvm_inj_virq(irq);
+ trace_kvm_inj_interrupt(vcpu);
++vcpu->stat.irq_injections;
if (vmx->rmode.vm86_active) {
@@ -4293,6 +4295,8 @@ static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
+ trace_kvm_inj_nmi(vcpu);
+
if (!enable_vnmi) {
/*
* Tracking the NMI-blocked state in software is built upon
@@ -6452,6 +6456,8 @@ static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
static void vmx_cancel_injection(struct kvm_vcpu *vcpu)
{
+ trace_kvm_cancel_inj(vcpu);
+
__vmx_complete_interrupts(vcpu,
vmcs_read32(VM_ENTRY_INTR_INFO_FIELD),
VM_ENTRY_INSTRUCTION_LEN,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3975331230b9..e09a76179c4b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6178,6 +6178,9 @@ static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
static bool inject_emulated_exception(struct kvm_vcpu *vcpu)
{
struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
+
+ trace_kvm_inj_emul_exception(vcpu, &ctxt->exception);
+
if (ctxt->exception.vector == PF_VECTOR)
return kvm_propagate_fault(vcpu, &ctxt->exception);
@@ -7487,10 +7490,6 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
/* try to inject new event if pending */
if (vcpu->arch.exception.pending) {
- trace_kvm_inj_exception(vcpu->arch.exception.nr,
- vcpu->arch.exception.has_error_code,
- vcpu->arch.exception.error_code);
-
WARN_ON_ONCE(vcpu->arch.exception.injected);
vcpu->arch.exception.pending = false;
vcpu->arch.exception.injected = true;
@@ -10250,7 +10249,10 @@ EXPORT_SYMBOL(kvm_arch_vcpu_intercept_desc);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
-EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_interrupt);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_nmi);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_exception);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cancel_inj);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr);
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