diff --git a/sys/cddl/dev/dtrace/riscv/dtrace_subr.c b/sys/cddl/dev/dtrace/riscv/dtrace_subr.c
--- a/sys/cddl/dev/dtrace/riscv/dtrace_subr.c
+++ b/sys/cddl/dev/dtrace/riscv/dtrace_subr.c
@@ -308,6 +308,9 @@
 		return (0);
 	}
 
+	if (match_opcode(invop, MATCH_C_NOP, MASK_C_NOP))
+		return (0);
+
 #ifdef INVARIANTS
 	panic("Instruction %x doesn't match any opcode.", invop);
 #endif