Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "31 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (31 commits)
  ocfs2: fix potential use after free
  mm/khugepaged: fix the xas_create_range() error path
  mm/khugepaged: collapse_shmem() do not crash on Compound
  mm/khugepaged: collapse_shmem() without freezing new_page
  mm/khugepaged: minor reorderings in collapse_shmem()
  mm/khugepaged: collapse_shmem() remember to clear holes
  mm/khugepaged: fix crashes due to misaccounted holes
  mm/khugepaged: collapse_shmem() stop if punched or truncated
  mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
  mm/huge_memory: splitting set mapping+index before unfreeze
  mm/huge_memory: rename freeze_page() to unmap_page()
  initramfs: clean old path before creating a hardlink
  kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
  psi: make disabling/enabling easier for vendor kernels
  proc: fixup map_files test on arm
  debugobjects: avoid recursive calls with kmemleak
  userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
  userfaultfd: shmem: add i_size checks
  userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
  userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
  ...

kernel/kcov.c

@@ -56,7 +56,7 @@ struct kcov {
 	struct task_struct	*t;
 };
 
-static bool check_kcov_mode(enum kcov_mode needed_mode, struct task_struct *t)
+static notrace bool check_kcov_mode(enum kcov_mode needed_mode, struct task_struct *t)
 {
 	unsigned int mode;
 
@@ -78,7 +78,7 @@ static bool check_kcov_mode(enum kcov_mode needed_mode, struct task_struct *t)
 	return mode == needed_mode;
 }
 
-static unsigned long canonicalize_ip(unsigned long ip)
+static notrace unsigned long canonicalize_ip(unsigned long ip)
 {
 #ifdef CONFIG_RANDOMIZE_BASE
 	ip -= kaslr_offset();

kernel/sched/psi.c

@@ -136,8 +136,18 @@
 
 static int psi_bug __read_mostly;
 
-bool psi_disabled __read_mostly;
-core_param(psi_disabled, psi_disabled, bool, 0644);
+DEFINE_STATIC_KEY_FALSE(psi_disabled);
+
+#ifdef CONFIG_PSI_DEFAULT_DISABLED
+bool psi_enable;
+#else
+bool psi_enable = true;
+#endif
+static int __init setup_psi(char *str)
+{
+	return kstrtobool(str, &psi_enable) == 0;
+}
+__setup("psi=", setup_psi);
 
 /* Running averages - we need to be higher-res than loadavg */
 #define PSI_FREQ	(2*HZ+1)	/* 2 sec intervals */
@@ -169,8 +179,10 @@ static void group_init(struct psi_group *group)
 
 void __init psi_init(void)
 {
-	if (psi_disabled)
+	if (!psi_enable) {
+		static_branch_enable(&psi_disabled);
 		return;
+	}
 
 	psi_period = jiffies_to_nsecs(PSI_FREQ);
 	group_init(&psi_system);
@@ -549,7 +561,7 @@ void psi_memstall_enter(unsigned long *flags)
 	struct rq_flags rf;
 	struct rq *rq;
 
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	*flags = current->flags & PF_MEMSTALL;
@@ -579,7 +591,7 @@ void psi_memstall_leave(unsigned long *flags)
 	struct rq_flags rf;
 	struct rq *rq;
 
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	if (*flags)
@@ -600,7 +612,7 @@ void psi_memstall_leave(unsigned long *flags)
 #ifdef CONFIG_CGROUPS
 int psi_cgroup_alloc(struct cgroup *cgroup)
 {
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return 0;
 
 	cgroup->psi.pcpu = alloc_percpu(struct psi_group_cpu);
@@ -612,7 +624,7 @@ int psi_cgroup_alloc(struct cgroup *cgroup)
 
 void psi_cgroup_free(struct cgroup *cgroup)
 {
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	cancel_delayed_work_sync(&cgroup->psi.clock_work);
@@ -637,7 +649,7 @@ void cgroup_move_task(struct task_struct *task, struct css_set *to)
 	struct rq_flags rf;
 	struct rq *rq;
 
-	if (psi_disabled) {
+	if (static_branch_likely(&psi_disabled)) {
 		/*
 		 * Lame to do this here, but the scheduler cannot be locked
 		 * from the outside, so we move cgroups from inside sched/.
@@ -673,7 +685,7 @@ int psi_show(struct seq_file *m, struct psi_group *group, enum psi_res res)
 {
 	int full;
 
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return -EOPNOTSUPP;
 
 	update_stats(group);

kernel/sched/stats.h

@@ -66,7 +66,7 @@ static inline void psi_enqueue(struct task_struct *p, bool wakeup)
 {
 	int clear = 0, set = TSK_RUNNING;
 
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	if (!wakeup || p->sched_psi_wake_requeue) {
@@ -86,7 +86,7 @@ static inline void psi_dequeue(struct task_struct *p, bool sleep)
 {
 	int clear = TSK_RUNNING, set = 0;
 
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	if (!sleep) {
@@ -102,7 +102,7 @@ static inline void psi_dequeue(struct task_struct *p, bool sleep)
 
 static inline void psi_ttwu_dequeue(struct task_struct *p)
 {
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 	/*
 	 * Is the task being migrated during a wakeup? Make sure to
@@ -128,7 +128,7 @@ static inline void psi_ttwu_dequeue(struct task_struct *p)
 
 static inline void psi_task_tick(struct rq *rq)
 {
-	if (psi_disabled)
+	if (static_branch_likely(&psi_disabled))
 		return;
 
 	if (unlikely(rq->curr->flags & PF_MEMSTALL))