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From:   Wonhyuk Yang <vvghjk1234@gmail.com>
To:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>
Cc:     Wonhyuk Yang <vvghjk1234@gmail.com>,
        Baik Song An <bsahn@etri.re.kr>,
        Hong Yeon Kim <kimhy@etri.re.kr>,
        Taeung Song <taeung@reallinux.co.kr>, linuxgeek@linuxgeek.io,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] KVM: Add extra information in kvm_page_fault trace point
Date:   Tue, 10 May 2022 16:10:00 +0900
Message-Id: <20220510071001.87169-1-vvghjk1234@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Currently, kvm_page_fault trace point provide fault_address and error
code. However it is not enough to find which cpu and instruction
cause kvm_page_faults. So add vcpu id and instruction pointer in
kvm_page_fault trace point.

Cc: Baik Song An <bsahn@etri.re.kr>
Cc: Hong Yeon Kim <kimhy@etri.re.kr>
Cc: Taeung Song <taeung@reallinux.co.kr>
Cc: linuxgeek@linuxgeek.io
Signed-off-by: Wonhyuk Yang <vvghjk1234@gmail.com>
---
 arch/x86/kvm/mmu/mmu.c |  2 +-
 arch/x86/kvm/svm/svm.c |  2 +-
 arch/x86/kvm/trace.h   | 12 +++++++++---
 arch/x86/kvm/vmx/vmx.c |  2 +-
 4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 311e4e1d7870..b9421060efa8 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4080,7 +4080,7 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code,
 
 	vcpu->arch.l1tf_flush_l1d = true;
 	if (!flags) {
-		trace_kvm_page_fault(fault_address, error_code);
+		trace_kvm_page_fault(vcpu, fault_address, error_code);
 
 		if (kvm_event_needs_reinjection(vcpu))
 			kvm_mmu_unprotect_page_virt(vcpu, fault_address);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7e45d03cd018..9741cfbf47a4 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1784,7 +1784,7 @@ static int npf_interception(struct kvm_vcpu *vcpu)
 	u64 fault_address = svm->vmcb->control.exit_info_2;
 	u64 error_code = svm->vmcb->control.exit_info_1;
 
-	trace_kvm_page_fault(fault_address, error_code);
+	trace_kvm_page_fault(vcpu, fault_address, error_code);
 	return kvm_mmu_page_fault(vcpu, fault_address, error_code,
 			static_cpu_has(X86_FEATURE_DECODEASSISTS) ?
 			svm->vmcb->control.insn_bytes : NULL,
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index e3a24b8f04be..78d20d392904 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -383,20 +383,26 @@ TRACE_EVENT(kvm_inj_exception,
  * Tracepoint for page fault.
  */
 TRACE_EVENT(kvm_page_fault,
-	TP_PROTO(unsigned long fault_address, unsigned int error_code),
-	TP_ARGS(fault_address, error_code),
+	TP_PROTO(struct kvm_vcpu *vcpu, unsigned long fault_address,
+		 unsigned int error_code),
+	TP_ARGS(vcpu, fault_address, error_code),
 
 	TP_STRUCT__entry(
+		__field(	unsigned int,	vcpu_id		)
+		__field(	unsigned long,	guest_rip	)
 		__field(	unsigned long,	fault_address	)
 		__field(	unsigned int,	error_code	)
 	),
 
 	TP_fast_assign(
+		__entry->vcpu_id	= vcpu->vcpu_id;
+		__entry->guest_rip	= kvm_rip_read(vcpu);
 		__entry->fault_address	= fault_address;
 		__entry->error_code	= error_code;
 	),
 
-	TP_printk("address %lx error_code %x",
+	TP_printk("vcpu %u rip 0x%lx address 0x%lx error_code %x",
+		  __entry->vcpu_id, __entry->guest_rip,
 		  __entry->fault_address, __entry->error_code)
 );
 
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 610355b9ccce..0f1edd02b68b 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5398,7 +5398,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu)
 		vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO, GUEST_INTR_STATE_NMI);
 
 	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
-	trace_kvm_page_fault(gpa, exit_qualification);
+	trace_kvm_page_fault(vcpu, gpa, exit_qualification);
 
 	/* Is it a read fault? */
 	error_code = (exit_qualification & EPT_VIOLATION_ACC_READ)
-- 
2.30.2