[2/2] KVM: arm64: Trace SMC in a way similar to HVC

Commit Message

Akihiko Odaki March 19, 2025, 11:38 a.m. UTC

KVM handles SMCCC calls from virtual EL2 that use the SMC instruction
since commit bd36b1a9eb5a ("KVM: arm64: nv: Handle SMCs taken from
virtual EL2"). Copy the tracepoint for HVC to the SMC handler to trace
SMCCC calls whether they come from either HVC or SMC.

Signed-off-by: Akihiko Odaki <[e-mail]>
---
 arch/arm64/kvm/handle_exit.c       |  3 +++
 arch/arm64/kvm/trace_handle_exit.h | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

Patch

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 512d152233ff..087880b645be 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -55,6 +55,9 @@  static int handle_hvc(struct kvm_vcpu *vcpu)
 
 static int handle_smc(struct kvm_vcpu *vcpu)
 {
+	trace_kvm_smc_arm64(*vcpu_pc(vcpu), vcpu_get_reg(vcpu, 0),
+			    kvm_vcpu_hvc_get_imm(vcpu));
+
 	/*
 	 * Forward this trapped smc instruction to the virtual EL2 if
 	 * the guest has asked for it.
diff --git a/arch/arm64/kvm/trace_handle_exit.h b/arch/arm64/kvm/trace_handle_exit.h
index b0308d95304d..a3a0e0a46c60 100644
--- a/arch/arm64/kvm/trace_handle_exit.h
+++ b/arch/arm64/kvm/trace_handle_exit.h
@@ -46,6 +46,26 @@  TRACE_EVENT(kvm_hvc_arm64,
 		  __entry->vcpu_pc, __entry->r0, __entry->imm)
 );
 
+TRACE_EVENT(kvm_smc_arm64,
+	TP_PROTO(unsigned long vcpu_pc, unsigned long r0, unsigned long imm),
+	TP_ARGS(vcpu_pc, r0, imm),
+
+	TP_STRUCT__entry(
+		__field(unsigned long, vcpu_pc)
+		__field(unsigned long, r0)
+		__field(unsigned long, imm)
+	),
+
+	TP_fast_assign(
+		__entry->vcpu_pc = vcpu_pc;
+		__entry->r0 = r0;
+		__entry->imm = imm;
+	),
+
+	TP_printk("SMC at 0x%016lx (r0: 0x%016lx, imm: 0x%lx)",
+		  __entry->vcpu_pc, __entry->r0, __entry->imm)
+);
+
 /*
  * The dreg32 name is a leftover from a distant past. This will really
  * output a 64bit value...