v4.19.13 snapshot.
diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
new file mode 100644
index 0000000..71f3e92
--- /dev/null
+++ b/arch/um/kernel/reboot.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <linux/sched/signal.h>
+#include <linux/sched/task.h>
+#include <linux/sched/mm.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/oom.h>
+#include <kern_util.h>
+#include <os.h>
+#include <skas.h>
+
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+static void kill_off_processes(void)
+{
+ struct task_struct *p;
+ int pid;
+
+ read_lock(&tasklist_lock);
+ for_each_process(p) {
+ struct task_struct *t;
+
+ t = find_lock_task_mm(p);
+ if (!t)
+ continue;
+ pid = t->mm->context.id.u.pid;
+ task_unlock(t);
+ os_kill_ptraced_process(pid, 1);
+ }
+ read_unlock(&tasklist_lock);
+}
+
+void uml_cleanup(void)
+{
+ kmalloc_ok = 0;
+ do_uml_exitcalls();
+ kill_off_processes();
+}
+
+void machine_restart(char * __unused)
+{
+ uml_cleanup();
+ reboot_skas();
+}
+
+void machine_power_off(void)
+{
+ uml_cleanup();
+ halt_skas();
+}
+
+void machine_halt(void)
+{
+ machine_power_off();
+}