Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h
index ecdc654..dfd82ea 100644
--- a/include/linux/sched/coredump.h
+++ b/include/linux/sched/coredump.h
@@ -72,6 +72,7 @@
 #define MMF_DISABLE_THP		24	/* disable THP for all VMAs */
 #define MMF_OOM_VICTIM		25	/* mm is the oom victim */
 #define MMF_OOM_REAP_QUEUED	26	/* mm was queued for oom_reaper */
+#define MMF_MULTIPROCESS	27	/* mm is shared between processes */
 #define MMF_DISABLE_THP_MASK	(1 << MMF_DISABLE_THP)
 
 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK |\
diff --git a/include/linux/sched/cpufreq.h b/include/linux/sched/cpufreq.h
index afa940c..cc6bcc1 100644
--- a/include/linux/sched/cpufreq.h
+++ b/include/linux/sched/cpufreq.h
@@ -12,6 +12,8 @@
 #define SCHED_CPUFREQ_MIGRATION	(1U << 1)
 
 #ifdef CONFIG_CPU_FREQ
+struct cpufreq_policy;
+
 struct update_util_data {
        void (*func)(struct update_util_data *data, u64 time, unsigned int flags);
 };
@@ -20,6 +22,7 @@
                        void (*func)(struct update_util_data *data, u64 time,
 				    unsigned int flags));
 void cpufreq_remove_update_util_hook(int cpu);
+bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy);
 
 static inline unsigned long map_util_freq(unsigned long util,
 					unsigned long freq, unsigned long cap)
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index c49257a..3a1d899 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -49,6 +49,8 @@
 		__mmdrop(mm);
 }
 
+void mmdrop(struct mm_struct *mm);
+
 /*
  * This has to be called after a get_task_mm()/mmget_not_zero()
  * followed by taking the mmap_sem for writing before modifying the
@@ -165,7 +167,8 @@
 	 * another oom-unkillable task does this it should blame itself.
 	 */
 	rcu_read_lock();
-	ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm;
+	ret = tsk->vfork_done &&
+			rcu_dereference(tsk->real_parent)->mm == tsk->mm;
 	rcu_read_unlock();
 
 	return ret;
diff --git a/include/linux/sched/nohz.h b/include/linux/sched/nohz.h
index 1abe91f..6d67e9a 100644
--- a/include/linux/sched/nohz.h
+++ b/include/linux/sched/nohz.h
@@ -15,9 +15,11 @@
 
 #ifdef CONFIG_NO_HZ_COMMON
 void calc_load_nohz_start(void);
+void calc_load_nohz_remote(struct rq *rq);
 void calc_load_nohz_stop(void);
 #else
 static inline void calc_load_nohz_start(void) { }
+static inline void calc_load_nohz_remote(struct rq *rq) { }
 static inline void calc_load_nohz_stop(void) { }
 #endif /* CONFIG_NO_HZ_COMMON */
 
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
index 8805025..b3f8847 100644
--- a/include/linux/sched/signal.h
+++ b/include/linux/sched/signal.h
@@ -224,7 +224,15 @@
 
 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
 					 * credential calculations
-					 * (notably. ptrace) */
+					 * (notably. ptrace)
+					 * Deprecated do not use in new code.
+					 * Use exec_update_lock instead.
+					 */
+	struct rw_semaphore exec_update_lock;	/* Held while task_struct is
+						 * being updated during exec,
+						 * and may have inconsistent
+						 * permissions.
+						 */
 } __randomize_layout;
 
 /*
@@ -501,6 +509,17 @@
 #define SEND_SIG_NOINFO ((struct kernel_siginfo *) 0)
 #define SEND_SIG_PRIV	((struct kernel_siginfo *) 1)
 
+static inline int __on_sig_stack(unsigned long sp)
+{
+#ifdef CONFIG_STACK_GROWSUP
+	return sp >= current->sas_ss_sp &&
+		sp - current->sas_ss_sp < current->sas_ss_size;
+#else
+	return sp > current->sas_ss_sp &&
+		sp - current->sas_ss_sp <= current->sas_ss_size;
+#endif
+}
+
 /*
  * True if we are on the alternate signal stack.
  */
@@ -518,13 +537,7 @@
 	if (current->sas_ss_flags & SS_AUTODISARM)
 		return 0;
 
-#ifdef CONFIG_STACK_GROWSUP
-	return sp >= current->sas_ss_sp &&
-		sp - current->sas_ss_sp < current->sas_ss_size;
-#else
-	return sp > current->sas_ss_sp &&
-		sp - current->sas_ss_sp <= current->sas_ss_size;
-#endif
+	return __on_sig_stack(sp);
 }
 
 static inline int sas_ss_flags(unsigned long sp)