diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index a0ab828b2cc5fc589335fe9ffe1c1462985288eb..2cb3b0916ebae70afad1f4a48844915638bf1476 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -471,7 +471,6 @@ static int acpi_bus_get_perf_flags(struct acpi_device *device)
    -------------------------------------------------------------------------- */
 
 static LIST_HEAD(acpi_bus_drivers);
-static DECLARE_MUTEX(acpi_bus_drivers_lock);
 
 /**
  * acpi_bus_match - match device IDs to driver's supported IDs