[PATCH 2/2] KVM: nVMX: trace nested vm entry

[Maxim Levitsky]

This is very helpful to debug nested VMX issues.

Signed-off-by: Maxim Levitsky <mlevi...@redhat.com>
---
 arch/x86/kvm/trace.h      | 30 ++++++++++++++++++++++++++++++
 arch/x86/kvm/vmx/nested.c |  5 +++++
 arch/x86/kvm/x86.c        |  3 ++-
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 2de30c20bc264..ec75efdac3560 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -554,6 +554,36 @@ TRACE_EVENT(kvm_nested_vmrun,
                __entry->npt ? "on" : "off")
 );
 
+
+/*
+ * Tracepoint for nested VMLAUNCH/VMRESUME
+ */
+TRACE_EVENT(kvm_nested_vmenter,
+           TP_PROTO(__u64 rip, __u64 vmcs, __u64 nested_rip,
+                    __u32 entry_intr_info),
+           TP_ARGS(rip, vmcs, nested_rip, entry_intr_info),
+
+       TP_STRUCT__entry(
+               __field(        __u64,          rip             )
+               __field(        __u64,          vmcs            )
+               __field(        __u64,          nested_rip      )
+               __field(        __u32,          entry_intr_info )
+       ),
+
+       TP_fast_assign(
+               __entry->rip                    = rip;
+               __entry->vmcs                   = vmcs;
+               __entry->nested_rip             = nested_rip;
+               __entry->entry_intr_info        = entry_intr_info;
+       ),
+
+       TP_printk("rip: 0x%016llx vmcs: 0x%016llx nrip: 0x%016llx "
+                 "entry_intr_info: 0x%08x",
+               __entry->rip, __entry->vmcs, __entry->nested_rip,
+               __entry->entry_intr_info)
+);
+
+
 TRACE_EVENT(kvm_nested_intercepts,
            TP_PROTO(__u16 cr_read, __u16 cr_write, __u32 exceptions,
                     __u32 intercept1, __u32 intercept2, __u32 intercept3),
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 0fbb46990dfce..20b0954f31bda 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3327,6 +3327,11 @@ enum nvmx_vmentry_status 
nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu,
                !(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS))
                vmx->nested.vmcs01_guest_bndcfgs = vmcs_read64(GUEST_BNDCFGS);
 
+       trace_kvm_nested_vmenter(kvm_rip_read(vcpu),
+                                vmx->nested.current_vmptr,
+                                vmcs12->guest_rip,
+                                vmcs12->vm_entry_intr_info_field);
+
        /*
         * Overwrite vmcs01.GUEST_CR3 with L1's CR3 if EPT is disabled *and*
         * nested early checks are disabled.  In the event of a "late" VM-Fail,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a480804ae27a3..757f4f88072af 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11562,11 +11562,12 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_cr);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed);
 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_nested_intr_vmexit);
-EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmenter_failed);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
-- 
2.26.2