diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c
index 2df4e5d..3196867 100644
--- a/arch/um/kernel/exec.c
+++ b/arch/um/kernel/exec.c
@@ -9,6 +9,7 @@
 #include <linux/ptrace.h>
 #include <linux/sched.h>
 #include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
 #include <linux/slab.h>
 #include <asm/current.h>
 #include <asm/processor.h>