Merge tag 'v5.4-rc4' into docs-next

I need to pick up the independent changes made to
Documentation/core-api/memory-allocation.rst to be able to merge further
work without creating a total mess.

28 files changed, 373 insertions, 226 deletions

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index d9daa3e422d0..c360f6a6c844 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -239,8 +239,8 @@ static int __init default_bdi_init(void)
 {
 	int err;
 
-	bdi_wq = alloc_workqueue("writeback", WQ_MEM_RECLAIM | WQ_FREEZABLE |
-					      WQ_UNBOUND | WQ_SYSFS, 0);
+	bdi_wq = alloc_workqueue("writeback", WQ_MEM_RECLAIM | WQ_UNBOUND |
+				 WQ_SYSFS, 0);
 	if (!bdi_wq)
 		return -ENOMEM;
 
diff --git a/mm/compaction.c b/mm/compaction.c
index ce08b39d85d4..672d3c78c6ab 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -270,14 +270,15 @@ __reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
 
 	/* Ensure the start of the pageblock or zone is online and valid */
 	block_pfn = pageblock_start_pfn(pfn);
-	block_page = pfn_to_online_page(max(block_pfn, zone->zone_start_pfn));
+	block_pfn = max(block_pfn, zone->zone_start_pfn);
+	block_page = pfn_to_online_page(block_pfn);
 	if (block_page) {
 		page = block_page;
 		pfn = block_pfn;
 	}
 
 	/* Ensure the end of the pageblock or zone is online and valid */
-	block_pfn += pageblock_nr_pages;
+	block_pfn = pageblock_end_pfn(pfn) - 1;
 	block_pfn = min(block_pfn, zone_end_pfn(zone) - 1);
 	end_page = pfn_to_online_page(block_pfn);
 	if (!end_page)
@@ -303,7 +304,7 @@ __reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
 
 		page += (1 << PAGE_ALLOC_COSTLY_ORDER);
 		pfn += (1 << PAGE_ALLOC_COSTLY_ORDER);
-	} while (page < end_page);
+	} while (page <= end_page);
 
 	return false;
 }
diff --git a/mm/filemap.c b/mm/filemap.c
index 1146fcfa3215..85b7d087eb45 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -40,6 +40,7 @@
 #include <linux/rmap.h>
 #include <linux/delayacct.h>
 #include <linux/psi.h>
+#include <linux/ramfs.h>
 #include "internal.h"
 
 #define CREATE_TRACE_POINTS
diff --git a/mm/gup.c b/mm/gup.c
index 23a9f9c9d377..8f236a335ae9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1973,7 +1973,8 @@ static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
 }
 
 static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
-		       unsigned long end, int write, struct page **pages, int *nr)
+		       unsigned long end, unsigned int flags,
+		       struct page **pages, int *nr)
 {
 	unsigned long pte_end;
 	struct page *head, *page;
@@ -1986,7 +1987,7 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 
 	pte = READ_ONCE(*ptep);
 
-	if (!pte_access_permitted(pte, write))
+	if (!pte_access_permitted(pte, flags & FOLL_WRITE))
 		return 0;
 
 	/* hugepages are never "special" */
@@ -2023,7 +2024,7 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 }
 
 static int gup_huge_pd(hugepd_t hugepd, unsigned long addr,
-		unsigned int pdshift, unsigned long end, int write,
+		unsigned int pdshift, unsigned long end, unsigned int flags,
 		struct page **pages, int *nr)
 {
 	pte_t *ptep;
@@ -2033,7 +2034,7 @@ static int gup_huge_pd(hugepd_t hugepd, unsigned long addr,
 	ptep = hugepte_offset(hugepd, addr, pdshift);
 	do {
 		next = hugepte_addr_end(addr, end, sz);
-		if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr))
+		if (!gup_hugepte(ptep, sz, addr, end, flags, pages, nr))
 			return 0;
 	} while (ptep++, addr = next, addr != end);
 
@@ -2041,7 +2042,7 @@ static int gup_huge_pd(hugepd_t hugepd, unsigned long addr,
 }
 #else
 static inline int gup_huge_pd(hugepd_t hugepd, unsigned long addr,
-		unsigned pdshift, unsigned long end, int write,
+		unsigned int pdshift, unsigned long end, unsigned int flags,
 		struct page **pages, int *nr)
 {
 	return 0;
@@ -2049,7 +2050,8 @@ static inline int gup_huge_pd(hugepd_t hugepd, unsigned long addr,
 #endif /* CONFIG_ARCH_HAS_HUGEPD */
 
 static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
-		unsigned long end, unsigned int flags, struct page **pages, int *nr)
+			unsigned long end, unsigned int flags,
+			struct page **pages, int *nr)
 {
 	struct page *head, *page;
 	int refs;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index c5cb6dcd6c69..13cc93785006 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2789,8 +2789,13 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 			ds_queue->split_queue_len--;
 			list_del(page_deferred_list(head));
 		}
-		if (mapping)
-			__dec_node_page_state(page, NR_SHMEM_THPS);
+		if (mapping) {
+			if (PageSwapBacked(page))
+				__dec_node_page_state(page, NR_SHMEM_THPS);
+			else
+				__dec_node_page_state(page, NR_FILE_THPS);
+		}
+
 		spin_unlock(&ds_queue->split_queue_lock);
 		__split_huge_page(page, list, end, flags);
 		if (PageSwapCache(head)) {
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ef37c85423a5..b45a95363a84 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1084,11 +1084,10 @@ static bool pfn_range_valid_gigantic(struct zone *z,
 	struct page *page;
 
 	for (i = start_pfn; i < end_pfn; i++) {
-		if (!pfn_valid(i))
+		page = pfn_to_online_page(i);
+		if (!page)
 			return false;
 
-		page = pfn_to_page(i);
-
 		if (page_zone(page) != z)
 			return false;
 
diff --git a/mm/init-mm.c b/mm/init-mm.c
index fb1e15028ef0..19603302a77f 100644
--- a/mm/init-mm.c
+++ b/mm/init-mm.c
@@ -5,6 +5,7 @@
 #include <linux/spinlock.h>
 #include <linux/list.h>
 #include <linux/cpumask.h>
+#include <linux/mman.h>
 
 #include <linux/atomic.h>
 #include <linux/user_namespace.h>
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 03a8d84badad..244607663363 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -527,6 +527,16 @@ static struct kmemleak_object *find_and_get_object(unsigned long ptr, int alias)
 }
 
 /*
+ * Remove an object from the object_tree_root and object_list. Must be called
+ * with the kmemleak_lock held _if_ kmemleak is still enabled.
+ */
+static void __remove_object(struct kmemleak_object *object)
+{
+	rb_erase(&object->rb_node, &object_tree_root);
+	list_del_rcu(&object->object_list);
+}
+
+/*
  * Look up an object in the object search tree and remove it from both
  * object_tree_root and object_list. The returned object's use_count should be
  * at least 1, as initially set by create_object().
@@ -538,10 +548,8 @@ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int ali
 
 	write_lock_irqsave(&kmemleak_lock, flags);
 	object = lookup_object(ptr, alias);
-	if (object) {
-		rb_erase(&object->rb_node, &object_tree_root);
-		list_del_rcu(&object->object_list);
-	}
+	if (object)
+		__remove_object(object);
 	write_unlock_irqrestore(&kmemleak_lock, flags);
 
 	return object;
@@ -1834,12 +1842,16 @@ static const struct file_operations kmemleak_fops = {
 
 static void __kmemleak_do_cleanup(void)
 {
-	struct kmemleak_object *object;
+	struct kmemleak_object *object, *tmp;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(object, &object_list, object_list)
-		delete_object_full(object->pointer);
-	rcu_read_unlock();
+	/*
+	 * Kmemleak has already been disabled, no need for RCU list traversal
+	 * or kmemleak_lock held.
+	 */
+	list_for_each_entry_safe(object, tmp, &object_list, object_list) {
+		__remove_object(object);
+		__delete_object(object);
+	}
 }
 
 /*
diff --git a/mm/memblock.c b/mm/memblock.c
index 7d4f61ae666a..c4b16cae2bc9 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1356,9 +1356,6 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
 		align = SMP_CACHE_BYTES;
 	}
 
-	if (end > memblock.current_limit)
-		end = memblock.current_limit;
-
 again:
 	found = memblock_find_in_range_node(size, align, start, end, nid,
 					    flags);
@@ -1469,6 +1466,9 @@ static void * __init memblock_alloc_internal(
 	if (WARN_ON_ONCE(slab_is_available()))
 		return kzalloc_node(size, GFP_NOWAIT, nid);
 
+	if (max_addr > memblock.current_limit)
+		max_addr = memblock.current_limit;
+
 	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid);
 
 	/* retry allocation without lower limit */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c313c49074ca..363106578876 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1567,6 +1567,11 @@ unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
 	return max;
 }
 
+unsigned long mem_cgroup_size(struct mem_cgroup *memcg)
+{
+	return page_counter_read(&memcg->memory);
+}
+
 static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 				     int order)
 {
@@ -5415,6 +5420,8 @@ static int mem_cgroup_move_account(struct page *page,
 				   struct mem_cgroup *from,
 				   struct mem_cgroup *to)
 {
+	struct lruvec *from_vec, *to_vec;
+	struct pglist_data *pgdat;
 	unsigned long flags;
 	unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
 	int ret;
@@ -5438,11 +5445,15 @@ static int mem_cgroup_move_account(struct page *page,
 
 	anon = PageAnon(page);
 
+	pgdat = page_pgdat(page);
+	from_vec = mem_cgroup_lruvec(pgdat, from);
+	to_vec = mem_cgroup_lruvec(pgdat, to);
+
 	spin_lock_irqsave(&from->move_lock, flags);
 
 	if (!anon && page_mapped(page)) {
-		__mod_memcg_state(from, NR_FILE_MAPPED, -nr_pages);
-		__mod_memcg_state(to, NR_FILE_MAPPED, nr_pages);
+		__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
+		__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
 	}
 
 	/*
@@ -5454,14 +5465,14 @@ static int mem_cgroup_move_account(struct page *page,
 		struct address_space *mapping = page_mapping(page);
 
 		if (mapping_cap_account_dirty(mapping)) {
-			__mod_memcg_state(from, NR_FILE_DIRTY, -nr_pages);
-			__mod_memcg_state(to, NR_FILE_DIRTY, nr_pages);
+			__mod_lruvec_state(from_vec, NR_FILE_DIRTY, -nr_pages);
+			__mod_lruvec_state(to_vec, NR_FILE_DIRTY, nr_pages);
 		}
 	}
 
 	if (PageWriteback(page)) {
-		__mod_memcg_state(from, NR_WRITEBACK, -nr_pages);
-		__mod_memcg_state(to, NR_WRITEBACK, nr_pages);
+		__mod_lruvec_state(from_vec, NR_WRITEBACK, -nr_pages);
+		__mod_lruvec_state(to_vec, NR_WRITEBACK, nr_pages);
 	}
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 7ef849da8278..3151c87dff73 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -199,7 +199,6 @@ struct to_kill {
 	struct task_struct *tsk;
 	unsigned long addr;
 	short size_shift;
-	char addr_valid;
 };
 
 /*
@@ -324,22 +323,27 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
 		}
 	}
 	tk->addr = page_address_in_vma(p, vma);
-	tk->addr_valid = 1;
 	if (is_zone_device_page(p))
 		tk->size_shift = dev_pagemap_mapping_shift(p, vma);
 	else
 		tk->size_shift = compound_order(compound_head(p)) + PAGE_SHIFT;
 
 	/*
-	 * In theory we don't have to kill when the page was
-	 * munmaped. But it could be also a mremap. Since that's
-	 * likely very rare kill anyways just out of paranoia, but use
-	 * a SIGKILL because the error is not contained anymore.
+	 * Send SIGKILL if "tk->addr == -EFAULT". Also, as
+	 * "tk->size_shift" is always non-zero for !is_zone_device_page(),
+	 * so "tk->size_shift == 0" effectively checks no mapping on
+	 * ZONE_DEVICE. Indeed, when a devdax page is mmapped N times
+	 * to a process' address space, it's possible not all N VMAs
+	 * contain mappings for the page, but at least one VMA does.
+	 * Only deliver SIGBUS with payload derived from the VMA that
+	 * has a mapping for the page.
 	 */
-	if (tk->addr == -EFAULT || tk->size_shift == 0) {
+	if (tk->addr == -EFAULT) {
 		pr_info("Memory failure: Unable to find user space address %lx in %s\n",
 			page_to_pfn(p), tsk->comm);
-		tk->addr_valid = 0;
+	} else if (tk->size_shift == 0) {
+		kfree(tk);
+		return;
 	}
 	get_task_struct(tsk);
 	tk->tsk = tsk;
@@ -366,7 +370,7 @@ static void kill_procs(struct list_head *to_kill, int forcekill, bool fail,
 			 * make sure the process doesn't catch the
 			 * signal and then access the memory. Just kill it.
 			 */
-			if (fail || tk->addr_valid == 0) {
+			if (fail || tk->addr == -EFAULT) {
 				pr_err("Memory failure: %#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
 				       pfn, tk->tsk->comm, tk->tsk->pid);
 				do_send_sig_info(SIGKILL, SEND_SIG_PRIV,
@@ -1253,17 +1257,19 @@ int memory_failure(unsigned long pfn, int flags)
 	if (!sysctl_memory_failure_recovery)
 		panic("Memory failure on page %lx", pfn);
 
-	if (!pfn_valid(pfn)) {
+	p = pfn_to_online_page(pfn);
+	if (!p) {
+		if (pfn_valid(pfn)) {
+			pgmap = get_dev_pagemap(pfn, NULL);
+			if (pgmap)
+				return memory_failure_dev_pagemap(pfn, flags,
+								  pgmap);
+		}
 		pr_err("Memory failure: %#lx: memory outside kernel control\n",
 			pfn);
 		return -ENXIO;
 	}
 
-	pgmap = get_dev_pagemap(pfn, NULL);
-	if (pgmap)
-		return memory_failure_dev_pagemap(pfn, flags, pgmap);
-
-	p = pfn_to_page(pfn);
 	if (PageHuge(p))
 		return memory_failure_hugetlb(pfn, flags);
 	if (TestSetPageHWPoison(p)) {
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index b1be791f772d..df570e5c71cc 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -436,67 +436,25 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 	zone_span_writeunlock(zone);
 }
 
-static void shrink_pgdat_span(struct pglist_data *pgdat,
-			      unsigned long start_pfn, unsigned long end_pfn)
+static void update_pgdat_span(struct pglist_data *pgdat)
 {
-	unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
-	unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */
-	unsigned long pgdat_end_pfn = p;
-	unsigned long pfn;
-	int nid = pgdat->node_id;
-
-	if (pgdat_start_pfn == start_pfn) {
-		/*
-		 * If the section is smallest section in the pgdat, it need
-		 * shrink pgdat->node_start_pfn and pgdat->node_spanned_pages.
-		 * In this case, we find second smallest valid mem_section
-		 * for shrinking zone.
-		 */
-		pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
-						pgdat_end_pfn);
-		if (pfn) {
-			pgdat->node_start_pfn = pfn;
-			pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
-		}
-	} else if (pgdat_end_pfn == end_pfn) {
-		/*
-		 * If the section is biggest section in the pgdat, it need
-		 * shrink pgdat->node_spanned_pages.
-		 * In this case, we find second biggest valid mem_section for
-		 * shrinking zone.
-		 */
-		pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
-					       start_pfn);
-		if (pfn)
-			pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
-	}
-
-	/*
-	 * If the section is not biggest or smallest mem_section in the pgdat,
-	 * it only creates a hole in the pgdat. So in this case, we need not
-	 * change the pgdat.
-	 * But perhaps, the pgdat has only hole data. Thus it check the pgdat
-	 * has only hole or not.
-	 */
-	pfn = pgdat_start_pfn;
-	for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SUBSECTION) {
-		if (unlikely(!pfn_valid(pfn)))
-			continue;
-
-		if (pfn_to_nid(pfn) != nid)
-			continue;
+	unsigned long node_start_pfn = 0, node_end_pfn = 0;
+	struct zone *zone;
 
-		/* Skip range to be removed */
-		if (pfn >= start_pfn && pfn < end_pfn)
-			continue;
+	for (zone = pgdat->node_zones;
+	     zone < pgdat->node_zones + MAX_NR_ZONES; zone++) {
+		unsigned long zone_end_pfn = zone->zone_start_pfn +
+					     zone->spanned_pages;
 
-		/* If we find valid section, we have nothing to do */
-		return;
+		/* No need to lock the zones, they can't change. */
+		if (zone_end_pfn > node_end_pfn)
+			node_end_pfn = zone_end_pfn;
+		if (zone->zone_start_pfn < node_start_pfn)
+			node_start_pfn = zone->zone_start_pfn;
 	}
 
-	/* The pgdat has no valid section */
-	pgdat->node_start_pfn = 0;
-	pgdat->node_spanned_pages = 0;
+	pgdat->node_start_pfn = node_start_pfn;
+	pgdat->node_spanned_pages = node_end_pfn - node_start_pfn;
 }
 
 static void __remove_zone(struct zone *zone, unsigned long start_pfn,
@@ -507,7 +465,7 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn,
 
 	pgdat_resize_lock(zone->zone_pgdat, &flags);
 	shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
-	shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
+	update_pgdat_span(pgdat);
 	pgdat_resize_unlock(zone->zone_pgdat, &flags);
 }
 
diff --git a/mm/memremap.c b/mm/memremap.c
index 32c79b51af86..03ccbdfeb697 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -13,8 +13,6 @@
 #include <linux/xarray.h>
 
 static DEFINE_XARRAY(pgmap_array);
-#define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1)
-#define SECTION_SIZE (1UL << PA_SECTION_SHIFT)
 
 #ifdef CONFIG_DEV_PAGEMAP_OPS
 DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
@@ -105,6 +103,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
 void memunmap_pages(struct dev_pagemap *pgmap)
 {
 	struct resource *res = &pgmap->res;
+	struct page *first_page;
 	unsigned long pfn;
 	int nid;
 
@@ -113,14 +112,16 @@ void memunmap_pages(struct dev_pagemap *pgmap)
 		put_page(pfn_to_page(pfn));
 	dev_pagemap_cleanup(pgmap);
 
+	/* make sure to access a memmap that was actually initialized */
+	first_page = pfn_to_page(pfn_first(pgmap));
+
 	/* pages are dead and unused, undo the arch mapping */
-	nid = page_to_nid(pfn_to_page(PHYS_PFN(res->start)));
+	nid = page_to_nid(first_page);
 
 	mem_hotplug_begin();
 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
-		pfn = PHYS_PFN(res->start);
-		__remove_pages(page_zone(pfn_to_page(pfn)), pfn,
-				 PHYS_PFN(resource_size(res)), NULL);
+		__remove_pages(page_zone(first_page), PHYS_PFN(res->start),
+			       PHYS_PFN(resource_size(res)), NULL);
 	} else {
 		arch_remove_memory(nid, res->start, resource_size(res),
 				pgmap_altmap(pgmap));
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 15c2050c629b..ecc3dbad606b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1175,11 +1175,17 @@ static __always_inline bool free_pages_prepare(struct page *page,
 		debug_check_no_obj_freed(page_address(page),
 					   PAGE_SIZE << order);
 	}
-	arch_free_page(page, order);
 	if (want_init_on_free())
 		kernel_init_free_pages(page, 1 << order);
 
 	kernel_poison_pages(page, 1 << order, 0);
+	/*
+	 * arch_free_page() can make the page's contents inaccessible.  s390
+	 * does this.  So nothing which can access the page's contents should
+	 * happen after this.
+	 */
+	arch_free_page(page, order);
+
 	if (debug_pagealloc_enabled())
 		kernel_map_pages(page, 1 << order, 0);
 
@@ -4467,12 +4473,14 @@ retry_cpuset:
 		if (page)
 			goto got_pg;
 
-		 if (order >= pageblock_order && (gfp_mask & __GFP_IO)) {
+		 if (order >= pageblock_order && (gfp_mask & __GFP_IO) &&
+		     !(gfp_mask & __GFP_RETRY_MAYFAIL)) {
 			/*
 			 * If allocating entire pageblock(s) and compaction
 			 * failed because all zones are below low watermarks
 			 * or is prohibited because it recently failed at this
-			 * order, fail immediately.
+			 * order, fail immediately unless the allocator has
+			 * requested compaction and reclaim retry.
 			 *
 			 * Reclaim is
 			 *  - potentially very expensive because zones are far
diff --git a/mm/page_ext.c b/mm/page_ext.c
index 5f5769c7db3b..4ade843ff588 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -67,8 +67,9 @@ static struct page_ext_operations *page_ext_ops[] = {
 #endif
 };
 
+unsigned long page_ext_size = sizeof(struct page_ext);
+
 static unsigned long total_usage;
-static unsigned long extra_mem;
 
 static bool __init invoke_need_callbacks(void)
 {
@@ -78,9 +79,8 @@ static bool __init invoke_need_callbacks(void)
 
 	for (i = 0; i < entries; i++) {
 		if (page_ext_ops[i]->need && page_ext_ops[i]->need()) {
-			page_ext_ops[i]->offset = sizeof(struct page_ext) +
-						extra_mem;
-			extra_mem += page_ext_ops[i]->size;
+			page_ext_ops[i]->offset = page_ext_size;
+			page_ext_size += page_ext_ops[i]->size;
 			need = true;
 		}
 	}
@@ -99,14 +99,9 @@ static void __init invoke_init_callbacks(void)
 	}
 }
 
-static unsigned long get_entry_size(void)
-{
-	return sizeof(struct page_ext) + extra_mem;
-}
-
 static inline struct page_ext *get_entry(void *base, unsigned long index)
 {
-	return base + get_entry_size() * index;
+	return base + page_ext_size * index;
 }
 
 #if !defined(CONFIG_SPARSEMEM)
@@ -156,7 +151,7 @@ static int __init alloc_node_page_ext(int nid)
 		!IS_ALIGNED(node_end_pfn(nid), MAX_ORDER_NR_PAGES))
 		nr_pages += MAX_ORDER_NR_PAGES;
 
-	table_size = get_entry_size() * nr_pages;
+	table_size = page_ext_size * nr_pages;
 
 	base = memblock_alloc_try_nid(
 			table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS),
@@ -234,7 +229,7 @@ static int __meminit init_section_page_ext(unsigned long pfn, int nid)
 	if (section->page_ext)
 		return 0;
 
-	table_size = get_entry_size() * PAGES_PER_SECTION;
+	table_size = page_ext_size * PAGES_PER_SECTION;
 	base = alloc_page_ext(table_size, nid);
 
 	/*
@@ -254,7 +249,7 @@ static int __meminit init_section_page_ext(unsigned long pfn, int nid)
 	 * we need to apply a mask.
 	 */
 	pfn &= PAGE_SECTION_MASK;
-	section->page_ext = (void *)base - get_entry_size() * pfn;
+	section->page_ext = (void *)base - page_ext_size * pfn;
 	total_usage += table_size;
 	return 0;
 }
@@ -267,7 +262,7 @@ static void free_page_ext(void *addr)
 		struct page *page = virt_to_page(addr);
 		size_t table_size;
 
-		table_size = get_entry_size() * PAGES_PER_SECTION;
+		table_size = page_ext_size * PAGES_PER_SECTION;
 
 		BUG_ON(PageReserved(page));
 		kmemleak_free(addr);
diff --git a/mm/page_owner.c b/mm/page_owner.c
index dee931184788..18ecde9f45b2 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -24,12 +24,10 @@ struct page_owner {
 	short last_migrate_reason;
 	gfp_t gfp_mask;
 	depot_stack_handle_t handle;
-#ifdef CONFIG_DEBUG_PAGEALLOC
 	depot_stack_handle_t free_handle;
-#endif
 };
 
-static bool page_owner_disabled = true;
+static bool page_owner_enabled = false;
 DEFINE_STATIC_KEY_FALSE(page_owner_inited);
 
 static depot_stack_handle_t dummy_handle;
@@ -44,7 +42,7 @@ static int __init early_page_owner_param(char *buf)
 		return -EINVAL;
 
 	if (strcmp(buf, "on") == 0)
-		page_owner_disabled = false;
+		page_owner_enabled = true;
 
 	return 0;
 }
@@ -52,10 +50,7 @@ early_param("page_owner", early_page_owner_param);
 
 static bool need_page_owner(void)
 {
-	if (page_owner_disabled)
-		return false;
-
-	return true;
+	return page_owner_enabled;
 }
 
 static __always_inline depot_stack_handle_t create_dummy_stack(void)
@@ -84,7 +79,7 @@ static noinline void register_early_stack(void)
 
 static void init_page_owner(void)
 {
-	if (page_owner_disabled)
+	if (!page_owner_enabled)
 		return;
 
 	register_dummy_stack();
@@ -148,25 +143,19 @@ void __reset_page_owner(struct page *page, unsigned int order)
 {
 	int i;
 	struct page_ext *page_ext;
-#ifdef CONFIG_DEBUG_PAGEALLOC
 	depot_stack_handle_t handle = 0;
 	struct page_owner *page_owner;
 
-	if (debug_pagealloc_enabled())
-		handle = save_stack(GFP_NOWAIT | __GFP_NOWARN);
-#endif
+	handle = save_stack(GFP_NOWAIT | __GFP_NOWARN);
 
+	page_ext = lookup_page_ext(page);
+	if (unlikely(!page_ext))
+		return;
 	for (i = 0; i < (1 << order); i++) {
-		page_ext = lookup_page_ext(page + i);
-		if (unlikely(!page_ext))
-			continue;
-		__clear_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags);
-#ifdef CONFIG_DEBUG_PAGEALLOC
-		if (debug_pagealloc_enabled()) {
-			page_owner = get_page_owner(page_ext);
-			page_owner->free_handle = handle;
-		}
-#endif
+		__clear_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags);
+		page_owner = get_page_owner(page_ext);
+		page_owner->free_handle = handle;
+		page_ext = page_ext_next(page_ext);
 	}
 }
 
@@ -184,9 +173,9 @@ static inline void __set_page_owner_handle(struct page *page,
 		page_owner->gfp_mask = gfp_mask;
 		page_owner->last_migrate_reason = -1;
 		__set_bit(PAGE_EXT_OWNER, &page_ext->flags);
-		__set_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags);
+		__set_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags);
 
-		page_ext = lookup_page_ext(page + i);
+		page_ext = page_ext_next(page_ext);
 	}
 }
 
@@ -224,12 +213,10 @@ void __split_page_owner(struct page *page, unsigned int order)
 	if (unlikely(!page_ext))
 		return;
 
-	page_owner = get_page_owner(page_ext);
-	page_owner->order = 0;
-	for (i = 1; i < (1 << order); i++) {
-		page_ext = lookup_page_ext(page + i);
+	for (i = 0; i < (1 << order); i++) {
 		page_owner = get_page_owner(page_ext);
 		page_owner->order = 0;
+		page_ext = page_ext_next(page_ext);
 	}
 }
 
@@ -260,7 +247,7 @@ void __copy_page_owner(struct page *oldpage, struct page *newpage)
 	 * the new page, which will be freed.
 	 */
 	__set_bit(PAGE_EXT_OWNER, &new_ext->flags);
-	__set_bit(PAGE_EXT_OWNER_ACTIVE, &new_ext->flags);
+	__set_bit(PAGE_EXT_OWNER_ALLOCATED, &new_ext->flags);
 }
 
 void pagetypeinfo_showmixedcount_print(struct seq_file *m,
@@ -284,7 +271,8 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m,
 	 * not matter as the mixed block count will still be correct
 	 */
 	for (; pfn < end_pfn; ) {
-		if (!pfn_valid(pfn)) {
+		page = pfn_to_online_page(pfn);
+		if (!page) {
 			pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
 			continue;
 		}
@@ -292,13 +280,13 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m,
 		block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
 		block_end_pfn = min(block_end_pfn, end_pfn);
 
-		page = pfn_to_page(pfn);
 		pageblock_mt = get_pageblock_migratetype(page);
 
 		for (; pfn < block_end_pfn; pfn++) {
 			if (!pfn_valid_within(pfn))
 				continue;
 
+			/* The pageblock is online, no need to recheck. */
 			page = pfn_to_page(pfn);
 
 			if (page_zone(page) != zone)
@@ -320,7 +308,7 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m,
 			if (unlikely(!page_ext))
 				continue;
 
-			if (!test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags))
+			if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags))
 				continue;
 
 			page_owner = get_page_owner(page_ext);
@@ -435,7 +423,7 @@ void __dump_page_owner(struct page *page)
 		return;
 	}
 
-	if (test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags))
+	if (test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags))
 		pr_alert("page_owner tracks the page as allocated\n");
 	else
 		pr_alert("page_owner tracks the page as freed\n");
@@ -451,7 +439,6 @@ void __dump_page_owner(struct page *page)
 		stack_trace_print(entries, nr_entries, 0);
 	}
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
 	handle = READ_ONCE(page_owner->free_handle);
 	if (!handle) {
 		pr_alert("page_owner free stack trace missing\n");
@@ -460,7 +447,6 @@ void __dump_page_owner(struct page *page)
 		pr_alert("page last free stack trace:\n");
 		stack_trace_print(entries, nr_entries, 0);
 	}
-#endif
 
 	if (page_owner->last_migrate_reason != -1)
 		pr_alert("page has been migrated, last migrate reason: %s\n",
@@ -527,7 +513,7 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 		 * Although we do have the info about past allocation of free
 		 * pages, it's not relevant for current memory usage.
 		 */
-		if (!test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags))
+		if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags))
 			continue;
 
 		page_owner = get_page_owner(page_ext);
diff --git a/mm/rmap.c b/mm/rmap.c
index d9a23bb773bf..0c7b2a9400d4 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -61,6 +61,7 @@
 #include <linux/mmu_notifier.h>
 #include <linux/migrate.h>
 #include <linux/hugetlb.h>
+#include <linux/huge_mm.h>
 #include <linux/backing-dev.h>
 #include <linux/page_idle.h>
 #include <linux/memremap.h>
diff --git a/mm/shmem.c b/mm/shmem.c
index cd570cc79c76..220be9fa2c41 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3482,6 +3482,12 @@ static int shmem_parse_options(struct fs_context *fc, void *data)
 {
 	char *options = data;
 
+	if (options) {
+		int err = security_sb_eat_lsm_opts(options, &fc->security);
+		if (err)
+			return err;
+	}
+
 	while (options != NULL) {
 		char *this_char = options;
 		for (;;) {
diff --git a/mm/shuffle.c b/mm/shuffle.c
index 3ce12481b1dc..b3fe97fd6654 100644
--- a/mm/shuffle.c
+++ b/mm/shuffle.c
@@ -33,7 +33,7 @@ __meminit void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
 }
 
 static bool shuffle_param;
-extern int shuffle_show(char *buffer, const struct kernel_param *kp)
+static int shuffle_show(char *buffer, const struct kernel_param *kp)
 {
 	return sprintf(buffer, "%c\n", test_bit(SHUFFLE_ENABLE, &shuffle_state)
 			? 'Y' : 'N');
diff --git a/mm/slab.c b/mm/slab.c
index 9df370558e5d..66e5d8032bae 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -4206,9 +4206,12 @@ void __check_heap_object(const void *ptr, unsigned long n, struct page *page,
 
 /**
  * __ksize -- Uninstrumented ksize.
+ * @objp: pointer to the object
  *
  * Unlike ksize(), __ksize() is uninstrumented, and does not provide the same
  * safety checks as ksize() with KASAN instrumentation enabled.
+ *
+ * Return: size of the actual memory used by @objp in bytes
  */
 size_t __ksize(const void *objp)
 {
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 6491c3a41805..f9fb27b4c843 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -178,10 +178,13 @@ static int init_memcg_params(struct kmem_cache *s,
 
 static void destroy_memcg_params(struct kmem_cache *s)
 {
-	if (is_root_cache(s))
+	if (is_root_cache(s)) {
 		kvfree(rcu_access_pointer(s->memcg_params.memcg_caches));
-	else
+	} else {
+		mem_cgroup_put(s->memcg_params.memcg);
+		WRITE_ONCE(s->memcg_params.memcg, NULL);
 		percpu_ref_exit(&s->memcg_params.refcnt);
+	}
 }
 
 static void free_memcg_params(struct rcu_head *rcu)
@@ -253,8 +256,6 @@ static void memcg_unlink_cache(struct kmem_cache *s)
 	} else {
 		list_del(&s->memcg_params.children_node);
 		list_del(&s->memcg_params.kmem_caches_node);
-		mem_cgroup_put(s->memcg_params.memcg);
-		WRITE_ONCE(s->memcg_params.memcg, NULL);
 	}
 }
 #else
@@ -1030,10 +1031,19 @@ void __init create_boot_cache(struct kmem_cache *s, const char *name,
 		unsigned int useroffset, unsigned int usersize)
 {
 	int err;
+	unsigned int align = ARCH_KMALLOC_MINALIGN;
 
 	s->name = name;
 	s->size = s->object_size = size;
-	s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
+
+	/*
+	 * For power of two sizes, guarantee natural alignment for kmalloc
+	 * caches, regardless of SL*B debugging options.
+	 */
+	if (is_power_of_2(size))
+		align = max(align, size);
+	s->align = calculate_alignment(flags, align, size);
+
 	s->useroffset = useroffset;
 	s->usersize = usersize;
 
@@ -1287,12 +1297,16 @@ void __init create_kmalloc_caches(slab_flags_t flags)
  */
 void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
 {
-	void *ret;
+	void *ret = NULL;
 	struct page *page;
 
 	flags |= __GFP_COMP;
 	page = alloc_pages(flags, order);
-	ret = page ? page_address(page) : NULL;
+	if (likely(page)) {
+		ret = page_address(page);
+		mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE,
+				    1 << order);
+	}
 	ret = kasan_kmalloc_large(ret, size, flags);
 	/* As ret might get tagged, call kmemleak hook after KASAN. */
 	kmemleak_alloc(ret, size, 1, flags);
diff --git a/mm/slob.c b/mm/slob.c
index cf377beab962..fa53e9f73893 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -190,7 +190,7 @@ static int slob_last(slob_t *s)
 
 static void *slob_new_pages(gfp_t gfp, int order, int node)
 {
-	void *page;
+	struct page *page;
 
 #ifdef CONFIG_NUMA
 	if (node != NUMA_NO_NODE)
@@ -202,14 +202,21 @@ static void *slob_new_pages(gfp_t gfp, int order, int node)
 	if (!page)
 		return NULL;
 
+	mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE,
+			    1 << order);
 	return page_address(page);
 }
 
 static void slob_free_pages(void *b, int order)
 {
+	struct page *sp = virt_to_page(b);
+
 	if (current->reclaim_state)
 		current->reclaim_state->reclaimed_slab += 1 << order;
-	free_pages((unsigned long)b, order);
+
+	mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE,
+			    -(1 << order));
+	__free_pages(sp, order);
 }
 
 /*
@@ -217,6 +224,7 @@ static void slob_free_pages(void *b, int order)
  * @sp: Page to look in.
  * @size: Size of the allocation.
  * @align: Allocation alignment.
+ * @align_offset: Offset in the allocated block that will be aligned.
  * @page_removed_from_list: Return parameter.
  *
  * Tries to find a chunk of memory at least @size bytes big within @page.
@@ -227,7 +235,7 @@ static void slob_free_pages(void *b, int order)
  *         true (set to false otherwise).
  */
 static void *slob_page_alloc(struct page *sp, size_t size, int align,
-			     bool *page_removed_from_list)
+			      int align_offset, bool *page_removed_from_list)
 {
 	slob_t *prev, *cur, *aligned = NULL;
 	int delta = 0, units = SLOB_UNITS(size);
@@ -236,8 +244,17 @@ static void *slob_page_alloc(struct page *sp, size_t size, int align,
 	for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) {
 		slobidx_t avail = slob_units(cur);
 
+		/*
+		 * 'aligned' will hold the address of the slob block so that the
+		 * address 'aligned'+'align_offset' is aligned according to the
+		 * 'align' parameter. This is for kmalloc() which prepends the
+		 * allocated block with its size, so that the block itself is
+		 * aligned when needed.
+		 */
 		if (align) {
-			aligned = (slob_t *)ALIGN((unsigned long)cur, align);
+			aligned = (slob_t *)
+				(ALIGN((unsigned long)cur + align_offset, align)
+				 - align_offset);
 			delta = aligned - cur;
 		}
 		if (avail >= units + delta) { /* room enough? */
@@ -281,7 +298,8 @@ static void *slob_page_alloc(struct page *sp, size_t size, int align,
 /*
  * slob_alloc: entry point into the slob allocator.
  */
-static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)
+static void *slob_alloc(size_t size, gfp_t gfp, int align, int node,
+							int align_offset)
 {
 	struct page *sp;
 	struct list_head *slob_list;
@@ -312,7 +330,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)
 		if (sp->units < SLOB_UNITS(size))
 			continue;
 
-		b = slob_page_alloc(sp, size, align, &page_removed_from_list);
+		b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list);
 		if (!b)
 			continue;
 
@@ -349,7 +367,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)
 		INIT_LIST_HEAD(&sp->slab_list);
 		set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE));
 		set_slob_page_free(sp, slob_list);
-		b = slob_page_alloc(sp, size, align, &_unused);
+		b = slob_page_alloc(sp, size, align, align_offset, &_unused);
 		BUG_ON(!b);
 		spin_unlock_irqrestore(&slob_lock, flags);
 	}
@@ -451,7 +469,7 @@ static __always_inline void *
 __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
 {
 	unsigned int *m;
-	int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+	int minalign = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
 	void *ret;
 
 	gfp &= gfp_allowed_mask;
@@ -459,19 +477,28 @@ __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller)
 	fs_reclaim_acquire(gfp);
 	fs_reclaim_release(gfp);
 
-	if (size < PAGE_SIZE - align) {
+	if (size < PAGE_SIZE - minalign) {
+		int align = minalign;
+
+		/*
+		 * For power of two sizes, guarantee natural alignment for
+		 * kmalloc()'d objects.
+		 */
+		if (is_power_of_2(size))
+			align = max(minalign, (int) size);
+
 		if (!size)
 			return ZERO_SIZE_PTR;
 
-		m = slob_alloc(size + align, gfp, align, node);
+		m = slob_alloc(size + minalign, gfp, align, node, minalign);
 
 		if (!m)
 			return NULL;
 		*m = size;
-		ret = (void *)m + align;
+		ret = (void *)m + minalign;
 
 		trace_kmalloc_node(caller, ret,
-				   size, size + align, gfp, node);
+				   size, size + minalign, gfp, node);
 	} else {
 		unsigned int order = get_order(size);
 
@@ -521,8 +548,13 @@ void kfree(const void *block)
 		int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
 		unsigned int *m = (unsigned int *)(block - align);
 		slob_free(m, *m + align);
-	} else
-		__free_pages(sp, compound_order(sp));
+	} else {
+		unsigned int order = compound_order(sp);
+		mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE,
+				    -(1 << order));
+		__free_pages(sp, order);
+
+	}
 }
 EXPORT_SYMBOL(kfree);
 
@@ -567,7 +599,7 @@ static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node)
 	fs_reclaim_release(flags);
 
 	if (c->size < PAGE_SIZE) {
-		b = slob_alloc(c->size, flags, c->align, node);
+		b = slob_alloc(c->size, flags, c->align, node, 0);
 		trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size,
 					    SLOB_UNITS(c->size) * SLOB_UNIT,
 					    flags, node);
diff --git a/mm/slub.c b/mm/slub.c
index 42c1b3af3c98..b25c807a111f 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2672,6 +2672,17 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
 }
 
 /*
+ * If the object has been wiped upon free, make sure it's fully initialized by
+ * zeroing out freelist pointer.
+ */
+static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s,
+						   void *obj)
+{
+	if (unlikely(slab_want_init_on_free(s)) && obj)
+		memset((void *)((char *)obj + s->offset), 0, sizeof(void *));
+}
+
+/*
  * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
  * have the fastpath folded into their functions. So no function call
  * overhead for requests that can be satisfied on the fastpath.
@@ -2759,12 +2770,8 @@ redo:
 		prefetch_freepointer(s, next_object);
 		stat(s, ALLOC_FASTPATH);
 	}
-	/*
-	 * If the object has been wiped upon free, make sure it's fully
-	 * initialized by zeroing out freelist pointer.
-	 */
-	if (unlikely(slab_want_init_on_free(s)) && object)
-		memset(object + s->offset, 0, sizeof(void *));
+
+	maybe_wipe_obj_freeptr(s, object);
 
 	if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object)
 		memset(object, 0, s->object_size);
@@ -3178,10 +3185,13 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 				goto error;
 
 			c = this_cpu_ptr(s->cpu_slab);
+			maybe_wipe_obj_freeptr(s, p[i]);
+
 			continue; /* goto for-loop */
 		}
 		c->freelist = get_freepointer(s, object);
 		p[i] = object;
+		maybe_wipe_obj_freeptr(s, p[i]);
 	}
 	c->tid = next_tid(c->tid);
 	local_irq_enable();
@@ -3821,11 +3831,15 @@ static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
 {
 	struct page *page;
 	void *ptr = NULL;
+	unsigned int order = get_order(size);
 
 	flags |= __GFP_COMP;
-	page = alloc_pages_node(node, flags, get_order(size));
-	if (page)
+	page = alloc_pages_node(node, flags, order);
+	if (page) {
 		ptr = page_address(page);
+		mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE,
+				    1 << order);
+	}
 
 	return kmalloc_large_node_hook(ptr, size, flags);
 }
@@ -3951,9 +3965,13 @@ void kfree(const void *x)
 
 	page = virt_to_head_page(x);
 	if (unlikely(!PageSlab(page))) {
+		unsigned int order = compound_order(page);
+
 		BUG_ON(!PageCompound(page));
 		kfree_hook(object);
-		__free_pages(page, compound_order(page));
+		mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE,
+				    -(1 << order));
+		__free_pages(page, order);
 		return;
 	}
 	slab_free(page->slab_cache, page, object, NULL, 1, _RET_IP_);
@@ -4838,7 +4856,17 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 		}
 	}
 
-	get_online_mems();
+	/*
+	 * It is impossible to take "mem_hotplug_lock" here with "kernfs_mutex"
+	 * already held which will conflict with an existing lock order:
+	 *
+	 * mem_hotplug_lock->slab_mutex->kernfs_mutex
+	 *
+	 * We don't really need mem_hotplug_lock (to hold off
+	 * slab_mem_going_offline_callback) here because slab's memory hot
+	 * unplug code doesn't destroy the kmem_cache->node[] data.
+	 */
+
 #ifdef CONFIG_SLUB_DEBUG
 	if (flags & SO_ALL) {
 		struct kmem_cache_node *n;
@@ -4879,7 +4907,6 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
 			x += sprintf(buf + x, " N%d=%lu",
 					node, nodes[node]);
 #endif
-	put_online_mems();
 	kfree(nodes);
 	return x + sprintf(buf + x, "\n");
 }
diff --git a/mm/sparse.c b/mm/sparse.c
index bf32de9e666b..f6891c1992b1 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -219,7 +219,7 @@ static inline unsigned long first_present_section_nr(void)
 	return next_present_section_nr(-1);
 }
 
-void subsection_mask_set(unsigned long *map, unsigned long pfn,
+static void subsection_mask_set(unsigned long *map, unsigned long pfn,
 		unsigned long nr_pages)
 {
 	int idx = subsection_map_index(pfn);
diff --git a/mm/truncate.c b/mm/truncate.c
index 8563339041f6..dd9ebc1da356 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -592,6 +592,16 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping,
 					unlock_page(page);
 					continue;
 				}
+
+				/* Take a pin outside pagevec */
+				get_page(page);
+
+				/*
+				 * Drop extra pins before trying to invalidate
+				 * the huge page.
+				 */
+				pagevec_remove_exceptionals(&pvec);
+				pagevec_release(&pvec);
 			}
 
 			ret = invalidate_inode_page(page);
@@ -602,6 +612,8 @@ unsigned long invalidate_mapping_pages(struct address_space *mapping,
 			 */
 			if (!ret)
 				deactivate_file_page(page);
+			if (PageTransHuge(page))
+				put_page(page);
 			count += ret;
 		}
 		pagevec_remove_exceptionals(&pvec);
diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index f3b50811497a..4bac22fe1aa2 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -355,6 +355,9 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio)
  * "hierarchy" or "local").
  *
  * To be used as memcg event method.
+ *
+ * Return: 0 on success, -ENOMEM on memory failure or -EINVAL if @args could
+ * not be parsed.
  */
 int vmpressure_register_event(struct mem_cgroup *memcg,
 			      struct eventfd_ctx *eventfd, const char *args)
@@ -362,7 +365,7 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
 	struct vmpressure *vmpr = memcg_to_vmpressure(memcg);
 	struct vmpressure_event *ev;
 	enum vmpressure_modes mode = VMPRESSURE_NO_PASSTHROUGH;
-	enum vmpressure_levels level = -1;
+	enum vmpressure_levels level;
 	char *spec, *spec_orig;
 	char *token;
 	int ret = 0;
@@ -375,20 +378,18 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
 
 	/* Find required level */
 	token = strsep(&spec, ",");
-	level = match_string(vmpressure_str_levels, VMPRESSURE_NUM_LEVELS, token);
-	if (level < 0) {
-		ret = level;
+	ret = match_string(vmpressure_str_levels, VMPRESSURE_NUM_LEVELS, token);
+	if (ret < 0)
 		goto out;
-	}
+	level = ret;
 
 	/* Find optional mode */
 	token = strsep(&spec, ",");
 	if (token) {
-		mode = match_string(vmpressure_str_modes, VMPRESSURE_NUM_MODES, token);
-		if (mode < 0) {
-			ret = mode;
+		ret = match_string(vmpressure_str_modes, VMPRESSURE_NUM_MODES, token);
+		if (ret < 0)
 			goto out;
-		}
+		mode = ret;
 	}
 
 	ev = kzalloc(sizeof(*ev), GFP_KERNEL);
@@ -404,6 +405,7 @@ int vmpressure_register_event(struct mem_cgroup *memcg,
 	mutex_lock(&vmpr->events_lock);
 	list_add(&ev->node, &vmpr->events);
 	mutex_unlock(&vmpr->events_lock);
+	ret = 0;
 out:
 	kfree(spec_orig);
 	return ret;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index e5d52d6a24af..ee4eecc7e1c2 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -351,12 +351,13 @@ unsigned long zone_reclaimable_pages(struct zone *zone)
  */
 unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx)
 {
-	unsigned long lru_size;
+	unsigned long lru_size = 0;
 	int zid;
 
-	if (!mem_cgroup_disabled())
-		lru_size = lruvec_page_state_local(lruvec, NR_LRU_BASE + lru);
-	else
+	if (!mem_cgroup_disabled()) {
+		for (zid = 0; zid < MAX_NR_ZONES; zid++)
+			lru_size += mem_cgroup_get_zone_lru_size(lruvec, lru, zid);
+	} else
 		lru_size = node_page_state(lruvec_pgdat(lruvec), NR_LRU_BASE + lru);
 
 	for (zid = zone_idx + 1; zid < MAX_NR_ZONES; zid++) {
@@ -932,10 +933,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 	 * Note that if SetPageDirty is always performed via set_page_dirty,
 	 * and thus under the i_pages lock, then this ordering is not required.
 	 */
-	if (unlikely(PageTransHuge(page)) && PageSwapCache(page))
-		refcount = 1 + HPAGE_PMD_NR;
-	else
-		refcount = 2;
+	refcount = 1 + compound_nr(page);
 	if (!page_ref_freeze(page, refcount))
 		goto cannot_free;
 	/* note: atomic_cmpxchg in page_ref_freeze provides the smp_rmb */
@@ -2459,17 +2457,70 @@ out:
 	*lru_pages = 0;
 	for_each_evictable_lru(lru) {
 		int file = is_file_lru(lru);
-		unsigned long size;
+		unsigned long lruvec_size;
 		unsigned long scan;
+		unsigned long protection;
+
+		lruvec_size = lruvec_lru_size(lruvec, lru, sc->reclaim_idx);
+		protection = mem_cgroup_protection(memcg,
+						   sc->memcg_low_reclaim);
+
+		if (protection) {
+			/*
+			 * Scale a cgroup's reclaim pressure by proportioning
+			 * its current usage to its memory.low or memory.min
+			 * setting.
+			 *
+			 * This is important, as otherwise scanning aggression
+			 * becomes extremely binary -- from nothing as we
+			 * approach the memory protection threshold, to totally
+			 * nominal as we exceed it.  This results in requiring
+			 * setting extremely liberal protection thresholds. It
+			 * also means we simply get no protection at all if we
+			 * set it too low, which is not ideal.
+			 *
+			 * If there is any protection in place, we reduce scan
+			 * pressure by how much of the total memory used is
+			 * within protection thresholds.
+			 *
+			 * There is one special case: in the first reclaim pass,
+			 * we skip over all groups that are within their low
+			 * protection. If that fails to reclaim enough pages to
+			 * satisfy the reclaim goal, we come back and override
+			 * the best-effort low protection. However, we still
+			 * ideally want to honor how well-behaved groups are in
+			 * that case instead of simply punishing them all
+			 * equally. As such, we reclaim them based on how much
+			 * memory they are using, reducing the scan pressure
+			 * again by how much of the total memory used is under
+			 * hard protection.
+			 */
+			unsigned long cgroup_size = mem_cgroup_size(memcg);
+
+			/* Avoid TOCTOU with earlier protection check */
+			cgroup_size = max(cgroup_size, protection);
+
+			scan = lruvec_size - lruvec_size * protection /
+				cgroup_size;
+
+			/*
+			 * Minimally target SWAP_CLUSTER_MAX pages to keep
+			 * reclaim moving forwards, avoiding decremeting
+			 * sc->priority further than desirable.
+			 */
+			scan = max(scan, SWAP_CLUSTER_MAX);
+		} else {
+			scan = lruvec_size;
+		}
+
+		scan >>= sc->priority;
 
-		size = lruvec_lru_size(lruvec, lru, sc->reclaim_idx);
-		scan = size >> sc->priority;
 		/*
 		 * If the cgroup's already been deleted, make sure to
 		 * scrape out the remaining cache.
 		 */
 		if (!scan && !mem_cgroup_online(memcg))
-			scan = min(size, SWAP_CLUSTER_MAX);
+			scan = min(lruvec_size, SWAP_CLUSTER_MAX);
 
 		switch (scan_balance) {
 		case SCAN_EQUAL:
@@ -2489,7 +2540,7 @@ out:
 		case SCAN_ANON:
 			/* Scan one type exclusively */
 			if ((scan_balance == SCAN_FILE) != file) {
-				size = 0;
+				lruvec_size = 0;
 				scan = 0;
 			}
 			break;
@@ -2498,7 +2549,7 @@ out:
 			BUG();
 		}
 
-		*lru_pages += size;
+		*lru_pages += lruvec_size;
 		nr[lru] = scan;
 	}
 }
@@ -2742,6 +2793,13 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 				memcg_memory_event(memcg, MEMCG_LOW);
 				break;
 			case MEMCG_PROT_NONE:
+				/*
+				 * All protection thresholds breached. We may
+				 * still choose to vary the scan pressure
+				 * applied based on by how much the cgroup in
+				 * question has exceeded its protection
+				 * thresholds (see get_scan_count).
+				 */
 				break;
 			}
 
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 05bdf90646e7..6d3d3f698ebb 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -998,9 +998,11 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 	struct z3fold_header *zhdr;
 	struct page *page;
 	enum buddy bud;
+	bool page_claimed;
 
 	zhdr = handle_to_z3fold_header(handle);
 	page = virt_to_page(zhdr);
+	page_claimed = test_and_set_bit(PAGE_CLAIMED, &page->private);
 
 	if (test_bit(PAGE_HEADLESS, &page->private)) {
 		/* if a headless page is under reclaim, just leave.
@@ -1008,7 +1010,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		 * has not been set before, we release this page
 		 * immediately so we don't care about its value any more.
 		 */
-		if (!test_and_set_bit(PAGE_CLAIMED, &page->private)) {
+		if (!page_claimed) {
 			spin_lock(&pool->lock);
 			list_del(&page->lru);
 			spin_unlock(&pool->lock);
@@ -1044,13 +1046,15 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		atomic64_dec(&pool->pages_nr);
 		return;
 	}
-	if (test_bit(PAGE_CLAIMED, &page->private)) {
+	if (page_claimed) {
+		/* the page has not been claimed by us */
 		z3fold_page_unlock(zhdr);
 		return;
 	}
 	if (unlikely(PageIsolated(page)) ||
 	    test_and_set_bit(NEEDS_COMPACTING, &page->private)) {
 		z3fold_page_unlock(zhdr);
+		clear_bit(PAGE_CLAIMED, &page->private);
 		return;
 	}
 	if (zhdr->cpu < 0 || !cpu_online(zhdr->cpu)) {
@@ -1060,10 +1064,12 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		zhdr->cpu = -1;
 		kref_get(&zhdr->refcount);
 		do_compact_page(zhdr, true);
+		clear_bit(PAGE_CLAIMED, &page->private);
 		return;
 	}
 	kref_get(&zhdr->refcount);
 	queue_work_on(zhdr->cpu, pool->compact_wq, &zhdr->work);
+	clear_bit(PAGE_CLAIMED, &page->private);
 	z3fold_page_unlock(zhdr);
 }