diff --git a/src/bpf_tracing.h b/src/bpf_tracing.h
index 01ce121..11f9096 100644
--- a/src/bpf_tracing.h
+++ b/src/bpf_tracing.h
@@ -233,7 +233,7 @@ struct pt_regs___arm64 {
 #define __PT_PARM5_REG a4
 #define __PT_RET_REG ra
 #define __PT_FP_REG s0
-#define __PT_RC_REG a5
+#define __PT_RC_REG a0
 #define __PT_SP_REG sp
 #define __PT_IP_REG pc
 /* riscv does not select ARCH_HAS_SYSCALL_WRAPPER. */