diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 0d1d23ea7925..8e6d552c40dd 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -30,6 +30,7 @@
 #include <linux/percpu.h>
 #include <linux/slab.h>
 #include <linux/kmemleak.h>
+#include <linux/notifier.h>
 #include <linux/cpu.h>
 #include <linux/string.h>
 #include <linux/bitops.h>
diff --git a/tools/testing/radix-tree/linux/cpu.h b/tools/testing/radix-tree/linux/cpu.h
index a45530d78107..7cf412103205 100644
--- a/tools/testing/radix-tree/linux/cpu.h
+++ b/tools/testing/radix-tree/linux/cpu.h
@@ -1 +1,21 @@
-#define cpuhp_setup_state_nocalls(a, b, c, d)	(0)
+
+#define hotcpu_notifier(a, b)
+
+#define CPU_ONLINE		0x0002 /* CPU (unsigned)v is up */
+#define CPU_UP_PREPARE		0x0003 /* CPU (unsigned)v coming up */
+#define CPU_UP_CANCELED		0x0004 /* CPU (unsigned)v NOT coming up */
+#define CPU_DOWN_PREPARE	0x0005 /* CPU (unsigned)v going down */
+#define CPU_DOWN_FAILED		0x0006 /* CPU (unsigned)v NOT going down */
+#define CPU_DEAD		0x0007 /* CPU (unsigned)v dead */
+#define CPU_POST_DEAD		0x0009 /* CPU (unsigned)v dead, cpu_hotplug
+					* lock is dropped */
+#define CPU_BROKEN		0x000C /* CPU (unsigned)v did not die properly,
+					* perhaps due to preemption. */
+#define CPU_TASKS_FROZEN	0x0010
+
+#define CPU_ONLINE_FROZEN	(CPU_ONLINE | CPU_TASKS_FROZEN)
+#define CPU_UP_PREPARE_FROZEN	(CPU_UP_PREPARE | CPU_TASKS_FROZEN)
+#define CPU_UP_CANCELED_FROZEN  (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
+#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
+#define CPU_DOWN_FAILED_FROZEN  (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
+#define CPU_DEAD_FROZEN		(CPU_DEAD | CPU_TASKS_FROZEN)
diff --git a/tools/testing/radix-tree/linux/notifier.h b/tools/testing/radix-tree/linux/notifier.h
new file mode 100644
index 000000000000..70e4797d5a46
--- /dev/null
+++ b/tools/testing/radix-tree/linux/notifier.h
@@ -0,0 +1,8 @@
+#ifndef _NOTIFIER_H
+#define _NOTIFIER_H
+
+struct notifier_block;
+
+#define NOTIFY_OK              0x0001          /* Suits me */
+
+#endif