diff --git a/src/bpf_tracing.h b/src/bpf_tracing.h
index 137b13d..6fb3d0f 100644
--- a/src/bpf_tracing.h
+++ b/src/bpf_tracing.h
@@ -204,6 +204,7 @@ struct pt_regs___s390 {
 #define __PT_PARM2_SYSCALL_REG __PT_PARM2_REG
 #define __PT_PARM3_SYSCALL_REG __PT_PARM3_REG
 #define __PT_PARM4_SYSCALL_REG __PT_PARM4_REG
+#define __PT_PARM5_SYSCALL_REG uregs[4]
 #define __PT_PARM6_SYSCALL_REG uregs[5]
 #define __PT_PARM7_SYSCALL_REG uregs[6]