diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 66a9d8145562..ae0010821ce3 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -447,7 +447,7 @@ static void acpi_processor_idle(void)
 
 		pr->power.bm_activity <<= diff;
 
-		acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
+		acpi_get_register_unlocked(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
 		if (bm_status) {
 			pr->power.bm_activity |= 0x1;
 			acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
@@ -1383,7 +1383,7 @@ static int acpi_idle_bm_check(void)
 {
 	u32 bm_status = 0;
 
-	acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
+	acpi_get_register_unlocked(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
 	if (bm_status)
 		acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
 	/*