diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 15e8b7c..8e3d69e 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -64,6 +64,11 @@
 		ret = poke_user(child, addr, data);
 		break;
 
+	case PTRACE_SYSEMU:
+	case PTRACE_SYSEMU_SINGLESTEP:
+		ret = -EIO;
+		break;
+
 	/* continue and stop at next (return from) syscall */
 	case PTRACE_SYSCALL:
 	/* restart after signal. */