19 files changed, 194 insertions, 92 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 229a5d5df977..3d55d95dcf49 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -11,7 +11,6 @@
  */
 #include <linux/bpf.h>
 #include <linux/err.h>
-#include <linux/vmalloc.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/filter.h>
@@ -74,14 +73,10 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 	if (array_size >= U32_MAX - PAGE_SIZE)
 		return ERR_PTR(-ENOMEM);
 
-
 	/* allocate all map elements and zero-initialize them */
-	array = kzalloc(array_size, GFP_USER | __GFP_NOWARN);
-	if (!array) {
-		array = vzalloc(array_size);
-		if (!array)
-			return ERR_PTR(-ENOMEM);
-	}
+	array = bpf_map_area_alloc(array_size);
+	if (!array)
+		return ERR_PTR(-ENOMEM);
 
 	/* copy mandatory map attributes */
 	array->map.map_type = attr->map_type;
@@ -97,7 +92,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 
 	if (array_size >= U32_MAX - PAGE_SIZE ||
 	    elem_size > PCPU_MIN_UNIT_SIZE || bpf_array_alloc_percpu(array)) {
-		kvfree(array);
+		bpf_map_area_free(array);
 		return ERR_PTR(-ENOMEM);
 	}
 out:
@@ -262,7 +257,7 @@ static void array_map_free(struct bpf_map *map)
 	if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY)
 		bpf_array_free_percpu(array);
 
-	kvfree(array);
+	bpf_map_area_free(array);
 }
 
 static const struct bpf_map_ops array_ops = {
@@ -319,7 +314,8 @@ static void fd_array_map_free(struct bpf_map *map)
 	/* make sure it's empty */
 	for (i = 0; i < array->map.max_entries; i++)
 		BUG_ON(array->ptrs[i] != NULL);
-	kvfree(array);
+
+	bpf_map_area_free(array);
 }
 
 static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 3f2bb58952d8..a753bbe7df0a 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -13,7 +13,6 @@
 #include <linux/bpf.h>
 #include <linux/jhash.h>
 #include <linux/filter.h>
-#include <linux/vmalloc.h>
 #include "percpu_freelist.h"
 #include "bpf_lru_list.h"
 
@@ -103,7 +102,7 @@ static void htab_free_elems(struct bpf_htab *htab)
 		free_percpu(pptr);
 	}
 free_elems:
-	vfree(htab->elems);
+	bpf_map_area_free(htab->elems);
 }
 
 static struct htab_elem *prealloc_lru_pop(struct bpf_htab *htab, void *key,
@@ -125,7 +124,8 @@ static int prealloc_init(struct bpf_htab *htab)
 {
 	int err = -ENOMEM, i;
 
-	htab->elems = vzalloc(htab->elem_size * htab->map.max_entries);
+	htab->elems = bpf_map_area_alloc(htab->elem_size *
+					 htab->map.max_entries);
 	if (!htab->elems)
 		return -ENOMEM;
 
@@ -320,14 +320,10 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 		goto free_htab;
 
 	err = -ENOMEM;
-	htab->buckets = kmalloc_array(htab->n_buckets, sizeof(struct bucket),
-				      GFP_USER | __GFP_NOWARN);
-
-	if (!htab->buckets) {
-		htab->buckets = vmalloc(htab->n_buckets * sizeof(struct bucket));
-		if (!htab->buckets)
-			goto free_htab;
-	}
+	htab->buckets = bpf_map_area_alloc(htab->n_buckets *
+					   sizeof(struct bucket));
+	if (!htab->buckets)
+		goto free_htab;
 
 	for (i = 0; i < htab->n_buckets; i++) {
 		INIT_HLIST_HEAD(&htab->buckets[i].head);
@@ -354,7 +350,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 free_extra_elems:
 	free_percpu(htab->extra_elems);
 free_buckets:
-	kvfree(htab->buckets);
+	bpf_map_area_free(htab->buckets);
 free_htab:
 	kfree(htab);
 	return ERR_PTR(err);
@@ -1014,7 +1010,7 @@ static void htab_map_free(struct bpf_map *map)
 		prealloc_destroy(htab);
 
 	free_percpu(htab->extra_elems);
-	kvfree(htab->buckets);
+	bpf_map_area_free(htab->buckets);
 	kfree(htab);
 }
 
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 732ae16d12b7..be8519148c25 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -7,7 +7,6 @@
 #include <linux/bpf.h>
 #include <linux/jhash.h>
 #include <linux/filter.h>
-#include <linux/vmalloc.h>
 #include <linux/stacktrace.h>
 #include <linux/perf_event.h>
 #include "percpu_freelist.h"
@@ -32,7 +31,7 @@ static int prealloc_elems_and_freelist(struct bpf_stack_map *smap)
 	u32 elem_size = sizeof(struct stack_map_bucket) + smap->map.value_size;
 	int err;
 
-	smap->elems = vzalloc(elem_size * smap->map.max_entries);
+	smap->elems = bpf_map_area_alloc(elem_size * smap->map.max_entries);
 	if (!smap->elems)
 		return -ENOMEM;
 
@@ -45,7 +44,7 @@ static int prealloc_elems_and_freelist(struct bpf_stack_map *smap)
 	return 0;
 
 free_elems:
-	vfree(smap->elems);
+	bpf_map_area_free(smap->elems);
 	return err;
 }
 
@@ -76,12 +75,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 	if (cost >= U32_MAX - PAGE_SIZE)
 		return ERR_PTR(-E2BIG);
 
-	smap = kzalloc(cost, GFP_USER | __GFP_NOWARN);
-	if (!smap) {
-		smap = vzalloc(cost);
-		if (!smap)
-			return ERR_PTR(-ENOMEM);
-	}
+	smap = bpf_map_area_alloc(cost);
+	if (!smap)
+		return ERR_PTR(-ENOMEM);
 
 	err = -E2BIG;
 	cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
@@ -112,7 +108,7 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 put_buffers:
 	put_callchain_buffers();
 free_smap:
-	kvfree(smap);
+	bpf_map_area_free(smap);
 	return ERR_PTR(err);
 }
 
@@ -262,9 +258,9 @@ static void stack_map_free(struct bpf_map *map)
 	/* wait for bpf programs to complete before freeing stack map */
 	synchronize_rcu();
 
-	vfree(smap->elems);
+	bpf_map_area_free(smap->elems);
 	pcpu_freelist_destroy(&smap->freelist);
-	kvfree(smap);
+	bpf_map_area_free(smap);
 	put_callchain_buffers();
 }
 
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 05ad086ab71d..08a4d287226b 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -13,6 +13,8 @@
 #include <linux/bpf_trace.h>
 #include <linux/syscalls.h>
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mmzone.h>
 #include <linux/anon_inodes.h>
 #include <linux/file.h>
 #include <linux/license.h>
@@ -50,6 +52,30 @@ void bpf_register_map_type(struct bpf_map_type_list *tl)
 	list_add(&tl->list_node, &bpf_map_types);
 }
 
+void *bpf_map_area_alloc(size_t size)
+{
+	/* We definitely need __GFP_NORETRY, so OOM killer doesn't
+	 * trigger under memory pressure as we really just want to
+	 * fail instead.
+	 */
+	const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO;
+	void *area;
+
+	if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
+		area = kmalloc(size, GFP_USER | flags);
+		if (area != NULL)
+			return area;
+	}
+
+	return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | flags,
+			 PAGE_KERNEL);
+}
+
+void bpf_map_area_free(void *area)
+{
+	kvfree(area);
+}
+
 int bpf_map_precharge_memlock(u32 pages)
 {
 	struct user_struct *user = get_current_user();
diff --git a/kernel/cpu.c b/kernel/cpu.c
index f75c4d031eeb..0a5f630f5c54 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -764,7 +764,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
 {
 	struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
 	int prev_state, ret = 0;
-	bool hasdied = false;
 
 	if (num_online_cpus() == 1)
 		return -EBUSY;
@@ -809,7 +808,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
 		cpuhp_kick_ap_work(cpu);
 	}
 
-	hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
 out:
 	cpu_hotplug_done();
 	return ret;
@@ -1302,10 +1300,24 @@ static int cpuhp_cb_check(enum cpuhp_state state)
  */
 static int cpuhp_reserve_state(enum cpuhp_state state)
 {
-	enum cpuhp_state i;
+	enum cpuhp_state i, end;
+	struct cpuhp_step *step;
 
-	for (i = CPUHP_AP_ONLINE_DYN; i <= CPUHP_AP_ONLINE_DYN_END; i++) {
-		if (!cpuhp_ap_states[i].name)
+	switch (state) {
+	case CPUHP_AP_ONLINE_DYN:
+		step = cpuhp_ap_states + CPUHP_AP_ONLINE_DYN;
+		end = CPUHP_AP_ONLINE_DYN_END;
+		break;
+	case CPUHP_BP_PREPARE_DYN:
+		step = cpuhp_bp_states + CPUHP_BP_PREPARE_DYN;
+		end = CPUHP_BP_PREPARE_DYN_END;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	for (i = state; i <= end; i++, step++) {
+		if (!step->name)
 			return i;
 	}
 	WARN(1, "No more dynamic states available for CPU hotplug\n");
@@ -1323,7 +1335,7 @@ static int cpuhp_store_callbacks(enum cpuhp_state state, const char *name,
 
 	mutex_lock(&cpuhp_state_mutex);
 
-	if (state == CPUHP_AP_ONLINE_DYN) {
+	if (state == CPUHP_AP_ONLINE_DYN || state == CPUHP_BP_PREPARE_DYN) {
 		ret = cpuhp_reserve_state(state);
 		if (ret < 0)
 			goto out;
diff --git a/kernel/module.c b/kernel/module.c
index 5088784c0cf9..38d4270925d4 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1145,7 +1145,7 @@ static size_t module_flags_taint(struct module *mod, char *buf)
 
 	for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
 		if (taint_flags[i].module && test_bit(i, &mod->taints))
-			buf[l++] = taint_flags[i].true;
+			buf[l++] = taint_flags[i].c_true;
 	}
 
 	return l;
diff --git a/kernel/panic.c b/kernel/panic.c
index c51edaa04fce..08aa88dde7de 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -249,7 +249,7 @@ void panic(const char *fmt, ...)
 		 * Delay timeout seconds before rebooting the machine.
 		 * We can't use the "normal" timers since we just panicked.
 		 */
-		pr_emerg("Rebooting in %d seconds..", panic_timeout);
+		pr_emerg("Rebooting in %d seconds..\n", panic_timeout);
 
 		for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) {
 			touch_nmi_watchdog();
@@ -355,7 +355,7 @@ const char *print_tainted(void)
 		for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
 			const struct taint_flag *t = &taint_flags[i];
 			*s++ = test_bit(i, &tainted_mask) ?
-					t->true : t->false;
+					t->c_true : t->c_false;
 		}
 		*s = 0;
 	} else
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index f67ceb7768b8..15e6baef5c73 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -46,7 +46,7 @@ static const char * const mem_sleep_labels[] = {
 const char *mem_sleep_states[PM_SUSPEND_MAX];
 
 suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE;
-suspend_state_t mem_sleep_default = PM_SUSPEND_MAX;
+static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM;
 
 unsigned int pm_suspend_global_flags;
 EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
@@ -168,7 +168,7 @@ void suspend_set_ops(const struct platform_suspend_ops *ops)
 	}
 	if (valid_state(PM_SUSPEND_MEM)) {
 		mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
-		if (mem_sleep_default >= PM_SUSPEND_MEM)
+		if (mem_sleep_default == PM_SUSPEND_MEM)
 			mem_sleep_current = PM_SUSPEND_MEM;
 	}
 
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 80adef7d4c3d..0d6ff3e471be 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -136,6 +136,7 @@ int rcu_jiffies_till_stall_check(void);
 #define TPS(x)  tracepoint_string(x)
 
 void rcu_early_boot_tests(void);
+void rcu_test_sync_prims(void);
 
 /*
  * This function really isn't for public consumption, but RCU is special in
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index 1898559e6b60..b23a4d076f3d 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -185,9 +185,6 @@ static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused
  * benefits of doing might_sleep() to reduce latency.)
  *
  * Cool, huh?  (Due to Josh Triplett.)
- *
- * But we want to make this a static inline later.  The cond_resched()
- * currently makes this problematic.
  */
 void synchronize_sched(void)
 {
@@ -195,7 +192,6 @@ void synchronize_sched(void)
 			 lock_is_held(&rcu_lock_map) ||
 			 lock_is_held(&rcu_sched_lock_map),
 			 "Illegal synchronize_sched() in RCU read-side critical section");
-	cond_resched();
 }
 EXPORT_SYMBOL_GPL(synchronize_sched);
 
diff --git a/kernel/rcu/tiny_plugin.h b/kernel/rcu/tiny_plugin.h
index 196f0302e2f4..c64b827ecbca 100644
--- a/kernel/rcu/tiny_plugin.h
+++ b/kernel/rcu/tiny_plugin.h
@@ -60,12 +60,17 @@ EXPORT_SYMBOL_GPL(rcu_scheduler_active);
 
 /*
  * During boot, we forgive RCU lockdep issues.  After this function is
- * invoked, we start taking RCU lockdep issues seriously.
+ * invoked, we start taking RCU lockdep issues seriously.  Note that unlike
+ * Tree RCU, Tiny RCU transitions directly from RCU_SCHEDULER_INACTIVE
+ * to RCU_SCHEDULER_RUNNING, skipping the RCU_SCHEDULER_INIT stage.
+ * The reason for this is that Tiny RCU does not need kthreads, so does
+ * not have to care about the fact that the scheduler is half-initialized
+ * at a certain phase of the boot process.
  */
 void __init rcu_scheduler_starting(void)
 {
 	WARN_ON(nr_context_switches() > 0);
-	rcu_scheduler_active = 1;
+	rcu_scheduler_active = RCU_SCHEDULER_RUNNING;
 }
 
 #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 96c52e43f7ca..cb4e2056ccf3 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -127,13 +127,16 @@ int rcu_num_nodes __read_mostly = NUM_RCU_NODES; /* Total # rcu_nodes in use. */
 int sysctl_panic_on_rcu_stall __read_mostly;
 
 /*
- * The rcu_scheduler_active variable transitions from zero to one just
- * before the first task is spawned.  So when this variable is zero, RCU
- * can assume that there is but one task, allowing RCU to (for example)
+ * The rcu_scheduler_active variable is initialized to the value
+ * RCU_SCHEDULER_INACTIVE and transitions RCU_SCHEDULER_INIT just before the
+ * first task is spawned.  So when this variable is RCU_SCHEDULER_INACTIVE,
+ * RCU can assume that there is but one task, allowing RCU to (for example)
  * optimize synchronize_rcu() to a simple barrier().  When this variable
- * is one, RCU must actually do all the hard work required to detect real
- * grace periods.  This variable is also used to suppress boot-time false
- * positives from lockdep-RCU error checking.
+ * is RCU_SCHEDULER_INIT, RCU must actually do all the hard work required
+ * to detect real grace periods.  This variable is also used to suppress
+ * boot-time false positives from lockdep-RCU error checking.  Finally, it
+ * transitions from RCU_SCHEDULER_INIT to RCU_SCHEDULER_RUNNING after RCU
+ * is fully initialized, including all of its kthreads having been spawned.
  */
 int rcu_scheduler_active __read_mostly;
 EXPORT_SYMBOL_GPL(rcu_scheduler_active);
@@ -3980,18 +3983,22 @@ static int __init rcu_spawn_gp_kthread(void)
 early_initcall(rcu_spawn_gp_kthread);
 
 /*
- * This function is invoked towards the end of the scheduler's initialization
- * process.  Before this is called, the idle task might contain
- * RCU read-side critical sections (during which time, this idle
- * task is booting the system).  After this function is called, the
- * idle tasks are prohibited from containing RCU read-side critical
- * sections.  This function also enables RCU lockdep checking.
+ * This function is invoked towards the end of the scheduler's
+ * initialization process.  Before this is called, the idle task might
+ * contain synchronous grace-period primitives (during which time, this idle
+ * task is booting the system, and such primitives are no-ops).  After this
+ * function is called, any synchronous grace-period primitives are run as
+ * expedited, with the requesting task driving the grace period forward.
+ * A later core_initcall() rcu_exp_runtime_mode() will switch to full
+ * runtime RCU functionality.
  */
 void rcu_scheduler_starting(void)
 {
 	WARN_ON(num_online_cpus() != 1);
 	WARN_ON(nr_context_switches() > 0);
-	rcu_scheduler_active = 1;
+	rcu_test_sync_prims();
+	rcu_scheduler_active = RCU_SCHEDULER_INIT;
+	rcu_test_sync_prims();
 }
 
 /*
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index d3053e99fdb6..e59e1849b89a 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -532,18 +532,28 @@ struct rcu_exp_work {
 };
 
 /*
+ * Common code to drive an expedited grace period forward, used by
+ * workqueues and mid-boot-time tasks.
+ */
+static void rcu_exp_sel_wait_wake(struct rcu_state *rsp,
+				  smp_call_func_t func, unsigned long s)
+{
+	/* Initialize the rcu_node tree in preparation for the wait. */
+	sync_rcu_exp_select_cpus(rsp, func);
+
+	/* Wait and clean up, including waking everyone. */
+	rcu_exp_wait_wake(rsp, s);
+}
+
+/*
  * Work-queue handler to drive an expedited grace period forward.
  */
 static void wait_rcu_exp_gp(struct work_struct *wp)
 {
 	struct rcu_exp_work *rewp;
 
-	/* Initialize the rcu_node tree in preparation for the wait. */
 	rewp = container_of(wp, struct rcu_exp_work, rew_work);
-	sync_rcu_exp_select_cpus(rewp->rew_rsp, rewp->rew_func);
-
-	/* Wait and clean up, including waking everyone. */
-	rcu_exp_wait_wake(rewp->rew_rsp, rewp->rew_s);
+	rcu_exp_sel_wait_wake(rewp->rew_rsp, rewp->rew_func, rewp->rew_s);
 }
 
 /*
@@ -569,12 +579,18 @@ static void _synchronize_rcu_expedited(struct rcu_state *rsp,
 	if (exp_funnel_lock(rsp, s))
 		return;  /* Someone else did our work for us. */
 
-	/* Marshall arguments and schedule the expedited grace period. */
-	rew.rew_func = func;
-	rew.rew_rsp = rsp;
-	rew.rew_s = s;
-	INIT_WORK_ONSTACK(&rew.rew_work, wait_rcu_exp_gp);
-	schedule_work(&rew.rew_work);
+	/* Ensure that load happens before action based on it. */
+	if (unlikely(rcu_scheduler_active == RCU_SCHEDULER_INIT)) {
+		/* Direct call during scheduler init and early_initcalls(). */
+		rcu_exp_sel_wait_wake(rsp, func, s);
+	} else {
+		/* Marshall arguments & schedule the expedited grace period. */
+		rew.rew_func = func;
+		rew.rew_rsp = rsp;
+		rew.rew_s = s;
+		INIT_WORK_ONSTACK(&rew.rew_work, wait_rcu_exp_gp);
+		schedule_work(&rew.rew_work);
+	}
 
 	/* Wait for expedited grace period to complete. */
 	rdp = per_cpu_ptr(rsp->rda, raw_smp_processor_id());
@@ -676,6 +692,8 @@ void synchronize_rcu_expedited(void)
 {
 	struct rcu_state *rsp = rcu_state_p;
 
+	if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE)
+		return;
 	_synchronize_rcu_expedited(rsp, sync_rcu_exp_handler);
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
@@ -693,3 +711,15 @@ void synchronize_rcu_expedited(void)
 EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
 
 #endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+
+/*
+ * Switch to run-time mode once Tree RCU has fully initialized.
+ */
+static int __init rcu_exp_runtime_mode(void)
+{
+	rcu_test_sync_prims();
+	rcu_scheduler_active = RCU_SCHEDULER_RUNNING;
+	rcu_test_sync_prims();
+	return 0;
+}
+core_initcall(rcu_exp_runtime_mode);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 85c5a883c6e3..56583e764ebf 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -670,7 +670,7 @@ void synchronize_rcu(void)
 			 lock_is_held(&rcu_lock_map) ||
 			 lock_is_held(&rcu_sched_lock_map),
 			 "Illegal synchronize_rcu() in RCU read-side critical section");
-	if (!rcu_scheduler_active)
+	if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE)
 		return;
 	if (rcu_gp_is_expedited())
 		synchronize_rcu_expedited();
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index f19271dce0a9..4f6db7e6a117 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -121,11 +121,14 @@ EXPORT_SYMBOL(rcu_read_lock_sched_held);
  * Should expedited grace-period primitives always fall back to their
  * non-expedited counterparts?  Intended for use within RCU.  Note
  * that if the user specifies both rcu_expedited and rcu_normal, then
- * rcu_normal wins.
+ * rcu_normal wins.  (Except during the time period during boot from
+ * when the first task is spawned until the rcu_exp_runtime_mode()
+ * core_initcall() is invoked, at which point everything is expedited.)
  */
 bool rcu_gp_is_normal(void)
 {
-	return READ_ONCE(rcu_normal);
+	return READ_ONCE(rcu_normal) &&
+	       rcu_scheduler_active != RCU_SCHEDULER_INIT;
 }
 EXPORT_SYMBOL_GPL(rcu_gp_is_normal);
 
@@ -135,13 +138,14 @@ static atomic_t rcu_expedited_nesting =
 /*
  * Should normal grace-period primitives be expedited?  Intended for
  * use within RCU.  Note that this function takes the rcu_expedited
- * sysfs/boot variable into account as well as the rcu_expedite_gp()
- * nesting.  So looping on rcu_unexpedite_gp() until rcu_gp_is_expedited()
- * returns false is a -really- bad idea.
+ * sysfs/boot variable and rcu_scheduler_active into account as well
+ * as the rcu_expedite_gp() nesting.  So looping on rcu_unexpedite_gp()
+ * until rcu_gp_is_expedited() returns false is a -really- bad idea.
  */
 bool rcu_gp_is_expedited(void)
 {
-	return rcu_expedited || atomic_read(&rcu_expedited_nesting);
+	return rcu_expedited || atomic_read(&rcu_expedited_nesting) ||
+	       rcu_scheduler_active == RCU_SCHEDULER_INIT;
 }
 EXPORT_SYMBOL_GPL(rcu_gp_is_expedited);
 
@@ -257,7 +261,7 @@ EXPORT_SYMBOL_GPL(rcu_callback_map);
 
 int notrace debug_lockdep_rcu_enabled(void)
 {
-	return rcu_scheduler_active && debug_locks &&
+	return rcu_scheduler_active != RCU_SCHEDULER_INACTIVE && debug_locks &&
 	       current->lockdep_recursion == 0;
 }
 EXPORT_SYMBOL_GPL(debug_lockdep_rcu_enabled);
@@ -591,7 +595,7 @@ EXPORT_SYMBOL_GPL(call_rcu_tasks);
 void synchronize_rcu_tasks(void)
 {
 	/* Complain if the scheduler has not started.  */
-	RCU_LOCKDEP_WARN(!rcu_scheduler_active,
+	RCU_LOCKDEP_WARN(rcu_scheduler_active == RCU_SCHEDULER_INACTIVE,
 			 "synchronize_rcu_tasks called too soon");
 
 	/* Wait for the grace period. */
@@ -813,6 +817,23 @@ static void rcu_spawn_tasks_kthread(void)
 
 #endif /* #ifdef CONFIG_TASKS_RCU */
 
+/*
+ * Test each non-SRCU synchronous grace-period wait API.  This is
+ * useful just after a change in mode for these primitives, and
+ * during early boot.
+ */
+void rcu_test_sync_prims(void)
+{
+	if (!IS_ENABLED(CONFIG_PROVE_RCU))
+		return;
+	synchronize_rcu();
+	synchronize_rcu_bh();
+	synchronize_sched();
+	synchronize_rcu_expedited();
+	synchronize_rcu_bh_expedited();
+	synchronize_sched_expedited();
+}
+
 #ifdef CONFIG_PROVE_RCU
 
 /*
@@ -865,6 +886,7 @@ void rcu_early_boot_tests(void)
 		early_boot_test_call_rcu_bh();
 	if (rcu_self_test_sched)
 		early_boot_test_call_rcu_sched();
+	rcu_test_sync_prims();
 }
 
 static int rcu_verify_early_boot_tests(void)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 8dbaec0e4f7f..1aea594a54db 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2475,6 +2475,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int
 				break;
 			if (neg)
 				continue;
+			val = convmul * val / convdiv;
 			if ((min && val < *min) || (max && val > *max))
 				continue;
 			*i = val;
diff --git a/kernel/ucount.c b/kernel/ucount.c
index 9d20d5dd298a..4bbd38ec3788 100644
--- a/kernel/ucount.c
+++ b/kernel/ucount.c
@@ -128,10 +128,10 @@ static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
 	struct hlist_head *hashent = ucounts_hashentry(ns, uid);
 	struct ucounts *ucounts, *new;
 
-	spin_lock(&ucounts_lock);
+	spin_lock_irq(&ucounts_lock);
 	ucounts = find_ucounts(ns, uid, hashent);
 	if (!ucounts) {
-		spin_unlock(&ucounts_lock);
+		spin_unlock_irq(&ucounts_lock);
 
 		new = kzalloc(sizeof(*new), GFP_KERNEL);
 		if (!new)
@@ -141,7 +141,7 @@ static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
 		new->uid = uid;
 		atomic_set(&new->count, 0);
 
-		spin_lock(&ucounts_lock);
+		spin_lock_irq(&ucounts_lock);
 		ucounts = find_ucounts(ns, uid, hashent);
 		if (ucounts) {
 			kfree(new);
@@ -152,16 +152,18 @@ static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
 	}
 	if (!atomic_add_unless(&ucounts->count, 1, INT_MAX))
 		ucounts = NULL;
-	spin_unlock(&ucounts_lock);
+	spin_unlock_irq(&ucounts_lock);
 	return ucounts;
 }
 
 static void put_ucounts(struct ucounts *ucounts)
 {
+	unsigned long flags;
+
 	if (atomic_dec_and_test(&ucounts->count)) {
-		spin_lock(&ucounts_lock);
+		spin_lock_irqsave(&ucounts_lock, flags);
 		hlist_del_init(&ucounts->node);
-		spin_unlock(&ucounts_lock);
+		spin_unlock_irqrestore(&ucounts_lock, flags);
 
 		kfree(ucounts);
 	}
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index d4b0fa01cae3..63177be0159e 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -49,6 +49,8 @@ unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask);
 #define for_each_watchdog_cpu(cpu) \
 	for_each_cpu_and((cpu), cpu_online_mask, &watchdog_cpumask)
 
+atomic_t watchdog_park_in_progress = ATOMIC_INIT(0);
+
 /*
  * The 'watchdog_running' variable is set to 1 when the watchdog threads
  * are registered/started and is set to 0 when the watchdog threads are
@@ -260,6 +262,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer)
 	int duration;
 	int softlockup_all_cpu_backtrace = sysctl_softlockup_all_cpu_backtrace;
 
+	if (atomic_read(&watchdog_park_in_progress) != 0)
+		return HRTIMER_NORESTART;
+
 	/* kick the hardlockup detector */
 	watchdog_interrupt_count();
 
@@ -467,12 +472,16 @@ static int watchdog_park_threads(void)
 {
 	int cpu, ret = 0;
 
+	atomic_set(&watchdog_park_in_progress, 1);
+
 	for_each_watchdog_cpu(cpu) {
 		ret = kthread_park(per_cpu(softlockup_watchdog, cpu));
 		if (ret)
 			break;
 	}
 
+	atomic_set(&watchdog_park_in_progress, 0);
+
 	return ret;
 }
 
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index 84016c8aee6b..12b8dd640786 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -84,6 +84,9 @@ static void watchdog_overflow_callback(struct perf_event *event,
 	/* Ensure the watchdog never gets throttled */
 	event->hw.interrupts = 0;
 
+	if (atomic_read(&watchdog_park_in_progress) != 0)
+		return;
+
 	if (__this_cpu_read(watchdog_nmi_touch) == true) {
 		__this_cpu_write(watchdog_nmi_touch, false);
 		return;