diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 7f70f3182d506ffc41ce61f370e047d514c34db3..4fcbd670415c6fa1a61b02a970563a5d220a9ea7 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -121,6 +121,13 @@ static int acpi_cpu_soft_notify(struct notifier_block *nfb,
 	struct acpi_processor *pr = per_cpu(processors, cpu);
 	struct acpi_device *device;
 
+	/*
+	 * CPU_STARTING and CPU_DYING must not sleep. Return here since
+	 * acpi_bus_get_device() may sleep.
+	 */
+	if (action == CPU_STARTING || action == CPU_DYING)
+		return NOTIFY_DONE;
+
 	if (!pr || acpi_bus_get_device(pr->handle, &device))
 		return NOTIFY_DONE;