Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
index 9e56bc4..74c2479 100644
--- a/drivers/cpuidle/cpuidle-pseries.c
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -247,7 +247,13 @@
 		return -ENODEV;
 
 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
-		if (lppaca_shared_proc(get_lppaca())) {
+		/*
+		 * Use local_paca instead of get_lppaca() since
+		 * preemption is not disabled, and it is not required in
+		 * fact, since lppaca_ptr does not need to be the value
+		 * associated to the current CPU, it can be from any CPU.
+		 */
+		if (lppaca_shared_proc(local_paca->lppaca_ptr)) {
 			cpuidle_state_table = shared_states;
 			max_idle_state = ARRAY_SIZE(shared_states);
 		} else {