Merge branch 'akpm' (incoming from Andrew)

Merge first batch of fixes from Andrew Morton:

 - A couple of kthread changes

 - A few minor audit patches

 - A number of fbdev patches.  Florian remains AWOL so I'm picking up
   some of these.

 - A few kbuild things

 - ocfs2 updates

 - Almost all of the MM queue

(And in the meantime, I already have the second big batch from Andrew
pending in my mailbox ;^)

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (149 commits)
  memcg: take reference before releasing rcu_read_lock
  mem hotunplug: fix kfree() of bootmem memory
  mmKconfig: add an option to disable bounce
  mm, nobootmem: do memset() after memblock_reserve()
  mm, nobootmem: clean-up of free_low_memory_core_early()
  fs/buffer.c: remove unnecessary init operation after allocating buffer_head.
  numa, cpu hotplug: change links of CPU and node when changing node number by onlining CPU
  mm: fix memory_hotplug.c printk format warning
  mm: swap: mark swap pages writeback before queueing for direct IO
  swap: redirty page if page write fails on swap file
  mm, memcg: give exiting processes access to memory reserves
  thp: fix huge zero page logic for page with pfn == 0
  memcg: avoid accessing memcg after releasing reference
  fs: fix fsync() error reporting
  memblock: fix missing comment of memblock_insert_region()
  mm: Remove unused parameter of pages_correctly_reserved()
  firmware, memmap: fix firmware_map_entry leak
  mm/vmstat: add note on safety of drain_zonestat
  mm: thp: add split tail pages to shrink page list in page reclaim
  mm: allow for outstanding swap writeback accounting
  ...

3 files changed, 54 insertions, 28 deletions

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index d8c7f3ee6e19..3d48fc887ef4 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -25,6 +25,15 @@ EXPORT_SYMBOL_GPL(cpu_subsys);
 static DEFINE_PER_CPU(struct device *, cpu_sys_devices);
 
 #ifdef CONFIG_HOTPLUG_CPU
+static void change_cpu_under_node(struct cpu *cpu,
+			unsigned int from_nid, unsigned int to_nid)
+{
+	int cpuid = cpu->dev.id;
+	unregister_cpu_under_node(cpuid, from_nid);
+	register_cpu_under_node(cpuid, to_nid);
+	cpu->node_id = to_nid;
+}
+
 static ssize_t show_online(struct device *dev,
 			   struct device_attribute *attr,
 			   char *buf)
@@ -39,17 +48,29 @@ static ssize_t __ref store_online(struct device *dev,
 				  const char *buf, size_t count)
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
+	int cpuid = cpu->dev.id;
+	int from_nid, to_nid;
 	ssize_t ret;
 
 	cpu_hotplug_driver_lock();
 	switch (buf[0]) {
 	case '0':
-		ret = cpu_down(cpu->dev.id);
+		ret = cpu_down(cpuid);
 		if (!ret)
 			kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
 		break;
 	case '1':
-		ret = cpu_up(cpu->dev.id);
+		from_nid = cpu_to_node(cpuid);
+		ret = cpu_up(cpuid);
+
+		/*
+		 * When hot adding memory to memoryless node and enabling a cpu
+		 * on the node, node number of the cpu may internally change.
+		 */
+		to_nid = cpu_to_node(cpuid);
+		if (from_nid != to_nid)
+			change_cpu_under_node(cpu, from_nid, to_nid);
+
 		if (!ret)
 			kobject_uevent(&dev->kobj, KOBJ_ONLINE);
 		break;
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index a51007b79032..14f8a6954da0 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -93,16 +93,6 @@ int register_memory(struct memory_block *memory)
 	return error;
 }
 
-static void
-unregister_memory(struct memory_block *memory)
-{
-	BUG_ON(memory->dev.bus != &memory_subsys);
-
-	/* drop the ref. we got in remove_memory_block() */
-	kobject_put(&memory->dev.kobj);
-	device_unregister(&memory->dev);
-}
-
 unsigned long __weak memory_block_size_bytes(void)
 {
 	return MIN_MEMORY_BLOCK_SIZE;
@@ -217,8 +207,7 @@ int memory_isolate_notify(unsigned long val, void *v)
  * The probe routines leave the pages reserved, just as the bootmem code does.
  * Make sure they're still that way.
  */
-static bool pages_correctly_reserved(unsigned long start_pfn,
-					unsigned long nr_pages)
+static bool pages_correctly_reserved(unsigned long start_pfn)
 {
 	int i, j;
 	struct page *page;
@@ -266,7 +255,7 @@ memory_block_action(unsigned long phys_index, unsigned long action, int online_t
 
 	switch (action) {
 		case MEM_ONLINE:
-			if (!pages_correctly_reserved(start_pfn, nr_pages))
+			if (!pages_correctly_reserved(start_pfn))
 				return -EBUSY;
 
 			ret = online_pages(start_pfn, nr_pages, online_type);
@@ -637,8 +626,28 @@ static int add_memory_section(int nid, struct mem_section *section,
 	return ret;
 }
 
-int remove_memory_block(unsigned long node_id, struct mem_section *section,
-		int phys_device)
+/*
+ * need an interface for the VM to add new memory regions,
+ * but without onlining it.
+ */
+int register_new_memory(int nid, struct mem_section *section)
+{
+	return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
+}
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static void
+unregister_memory(struct memory_block *memory)
+{
+	BUG_ON(memory->dev.bus != &memory_subsys);
+
+	/* drop the ref. we got in remove_memory_block() */
+	kobject_put(&memory->dev.kobj);
+	device_unregister(&memory->dev);
+}
+
+static int remove_memory_block(unsigned long node_id,
+			       struct mem_section *section, int phys_device)
 {
 	struct memory_block *mem;
 
@@ -661,15 +670,6 @@ int remove_memory_block(unsigned long node_id, struct mem_section *section,
 	return 0;
 }
 
-/*
- * need an interface for the VM to add new memory regions,
- * but without onlining it.
- */
-int register_new_memory(int nid, struct mem_section *section)
-{
-	return add_memory_section(nid, section, NULL, MEM_OFFLINE, HOTPLUG);
-}
-
 int unregister_memory_section(struct mem_section *section)
 {
 	if (!present_section(section))
@@ -677,6 +677,7 @@ int unregister_memory_section(struct mem_section *section)
 
 	return remove_memory_block(0, section, 0);
 }
+#endif /* CONFIG_MEMORY_HOTREMOVE */
 
 /*
  * offline one memory block. If the memory block has been offlined, do nothing.
diff --git a/drivers/base/node.c b/drivers/base/node.c
index fac124a7e1c5..7616a77ca322 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -7,6 +7,7 @@
 #include <linux/mm.h>
 #include <linux/memory.h>
 #include <linux/vmstat.h>
+#include <linux/notifier.h>
 #include <linux/node.h>
 #include <linux/hugetlb.h>
 #include <linux/compaction.h>
@@ -683,8 +684,11 @@ static int __init register_node_type(void)
 
 	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
 	if (!ret) {
-		hotplug_memory_notifier(node_memory_callback,
-					NODE_CALLBACK_PRI);
+		static struct notifier_block node_memory_callback_nb = {
+			.notifier_call = node_memory_callback,
+			.priority = NODE_CALLBACK_PRI,
+		};
+		register_hotmemory_notifier(&node_memory_callback_nb);
 	}
 
 	/*