Merge branch 'master' into for-next

Pull linus#master to merge PER_CPU_DEF_ATTRIBUTES and alpha build fix
changes.  As alpha in percpu tree uses 'weak' attribute instead of
inline assembly, there's no need for __used attribute.

Conflicts:
	arch/alpha/include/asm/percpu.h
	arch/mn10300/kernel/vmlinux.lds.S
	include/linux/percpu-defs.h

12 files changed, 193 insertions, 243 deletions

diff --git a/mm/dmapool.c b/mm/dmapool.c
index b1f0885dda22..3df063706f53 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -86,10 +86,12 @@ show_pools(struct device *dev, struct device_attribute *attr, char *buf)
                 unsigned pages = 0;
                 unsigned blocks = 0;
 
+                spin_lock_irq(&pool->lock);
                 list_for_each_entry(page, &pool->page_list, page_list) {
                         pages++;
                         blocks += page->in_use;
                 }
+                spin_unlock_irq(&pool->lock);
 
                 /* per-pool info, no real statistics yet */
                 temp = scnprintf(next, size, "%-16s %4u %4Zu %4Zu %2u\n",
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index a56e6f3ce979..d0351e31f474 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1985,7 +1985,7 @@ static struct page *hugetlbfs_pagecache_page(struct hstate *h,
 }
 
 static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
-                        unsigned long address, pte_t *ptep, int write_access)
+                        unsigned long address, pte_t *ptep, unsigned int flags)
 {
         struct hstate *h = hstate_vma(vma);
         int ret = VM_FAULT_SIGBUS;
@@ -2053,7 +2053,7 @@ retry:
          * any allocations necessary to record that reservation occur outside
          * the spinlock.
          */
-        if (write_access && !(vma->vm_flags & VM_SHARED))
+        if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED))
                 if (vma_needs_reservation(h, vma, address) < 0) {
                         ret = VM_FAULT_OOM;
                         goto backout_unlocked;
@@ -2072,7 +2072,7 @@ retry:
                                 && (vma->vm_flags & VM_SHARED)));
         set_huge_pte_at(mm, address, ptep, new_pte);
 
-        if (write_access && !(vma->vm_flags & VM_SHARED)) {
+        if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
                 /* Optimization, do the COW without a second fault */
                 ret = hugetlb_cow(mm, vma, address, ptep, new_pte, page);
         }
@@ -2091,7 +2091,7 @@ backout_unlocked:
 }
 
 int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
-                        unsigned long address, int write_access)
+                        unsigned long address, unsigned int flags)
 {
         pte_t *ptep;
         pte_t entry;
@@ -2112,7 +2112,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         mutex_lock(&hugetlb_instantiation_mutex);
         entry = huge_ptep_get(ptep);
         if (huge_pte_none(entry)) {
-                ret = hugetlb_no_page(mm, vma, address, ptep, write_access);
+                ret = hugetlb_no_page(mm, vma, address, ptep, flags);
                 goto out_mutex;
         }
 
@@ -2126,7 +2126,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
          * page now as it is used to determine if a reservation has been
          * consumed.
          */
-        if (write_access && !pte_write(entry)) {
+        if ((flags & FAULT_FLAG_WRITE) && !pte_write(entry)) {
                 if (vma_needs_reservation(h, vma, address) < 0) {
                         ret = VM_FAULT_OOM;
                         goto out_mutex;
@@ -2143,7 +2143,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                 goto out_page_table_lock;
 
 
-        if (write_access) {
+        if (flags & FAULT_FLAG_WRITE) {
                 if (!pte_write(entry)) {
                         ret = hugetlb_cow(mm, vma, address, ptep, entry,
                                                         pagecache_page);
@@ -2152,7 +2152,8 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                 entry = pte_mkdirty(entry);
         }
         entry = pte_mkyoung(entry);
-        if (huge_ptep_set_access_flags(vma, address, ptep, entry, write_access))
+        if (huge_ptep_set_access_flags(vma, address, ptep, entry,
+                                                flags & FAULT_FLAG_WRITE))
                 update_mmu_cache(vma, address, entry);
 
 out_page_table_lock:
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index ec759b60077a..e766e1da09d2 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -48,10 +48,10 @@
  *   scanned. This list is only modified during a scanning episode when the
  *   scan_mutex is held. At the end of a scan, the gray_list is always empty.
  *   Note that the kmemleak_object.use_count is incremented when an object is
- *   added to the gray_list and therefore cannot be freed
- * - kmemleak_mutex (mutex): prevents multiple users of the "kmemleak" debugfs
- *   file together with modifications to the memory scanning parameters
- *   including the scan_thread pointer
+ *   added to the gray_list and therefore cannot be freed. This mutex also
+ *   prevents multiple users of the "kmemleak" debugfs file together with
+ *   modifications to the memory scanning parameters including the scan_thread
+ *   pointer
  *
  * The kmemleak_object structures have a use_count incremented or decremented
  * using the get_object()/put_object() functions. When the use_count becomes
@@ -61,6 +61,8 @@
  * structure.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -103,7 +105,6 @@
 #define MAX_TRACE               16      /* stack trace length */
 #define REPORTS_NR              50      /* maximum number of reported leaks */
 #define MSECS_MIN_AGE           5000    /* minimum object age for reporting */
-#define MSECS_SCAN_YIELD        10      /* CPU yielding period */
 #define SECS_FIRST_SCAN         60      /* delay before the first scan */
 #define SECS_SCAN_WAIT          600     /* subsequent auto scanning delay */
 
@@ -184,19 +185,16 @@ static atomic_t kmemleak_error = ATOMIC_INIT(0);
 static unsigned long min_addr = ULONG_MAX;
 static unsigned long max_addr;
 
-/* used for yielding the CPU to other tasks during scanning */
-static unsigned long next_scan_yield;
 static struct task_struct *scan_thread;
-static unsigned long jiffies_scan_yield;
+/* used to avoid reporting of recently allocated objects */
 static unsigned long jiffies_min_age;
+static unsigned long jiffies_last_scan;
 /* delay between automatic memory scannings */
 static signed long jiffies_scan_wait;
 /* enables or disables the task stacks scanning */
-static int kmemleak_stack_scan;
-/* mutex protecting the memory scanning */
+static int kmemleak_stack_scan = 1;
+/* protects the memory scanning, parameters and debug/kmemleak file access */
 static DEFINE_MUTEX(scan_mutex);
-/* mutex protecting the access to the /sys/kernel/debug/kmemleak file */
-static DEFINE_MUTEX(kmemleak_mutex);
 
 /* number of leaks reported (for limitation purposes) */
 static int reported_leaks;
@@ -233,7 +231,7 @@ struct early_log {
 };
 
 /* early logging buffer and current position */
-static struct early_log early_log[200];
+static struct early_log early_log[CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE];
 static int crt_early_log;
 
 static void kmemleak_disable(void);
@@ -277,15 +275,6 @@ static int color_gray(const struct kmemleak_object *object)
 }
 
 /*
- * Objects are considered referenced if their color is gray and they have not
- * been deleted.
- */
-static int referenced_object(struct kmemleak_object *object)
-{
-        return (object->flags & OBJECT_ALLOCATED) && color_gray(object);
-}
-
-/*
  * Objects are considered unreferenced only if their color is white, they have
  * not be deleted and have a minimum age to avoid false positives caused by
  * pointers temporarily stored in CPU registers.
@@ -293,42 +282,28 @@ static int referenced_object(struct kmemleak_object *object)
 static int unreferenced_object(struct kmemleak_object *object)
 {
         return (object->flags & OBJECT_ALLOCATED) && color_white(object) &&
-                time_is_before_eq_jiffies(object->jiffies + jiffies_min_age);
+                time_before_eq(object->jiffies + jiffies_min_age,
+                               jiffies_last_scan);
 }
 
 /*
- * Printing of the (un)referenced objects information, either to the seq file
- * or to the kernel log. The print_referenced/print_unreferenced functions
- * must be called with the object->lock held.
+ * Printing of the unreferenced objects information to the seq file. The
+ * print_unreferenced function must be called with the object->lock held.
  */
-#define print_helper(seq, x...) do {    \
-        struct seq_file *s = (seq);     \
-        if (s)                          \
-                seq_printf(s, x);       \
-        else                            \
-                pr_info(x);             \
-} while (0)
-
-static void print_referenced(struct kmemleak_object *object)
-{
-        pr_info("kmemleak: referenced object 0x%08lx (size %zu)\n",
-                object->pointer, object->size);
-}
-
 static void print_unreferenced(struct seq_file *seq,
                                struct kmemleak_object *object)
 {
         int i;
 
-        print_helper(seq, "kmemleak: unreferenced object 0x%08lx (size %zu):\n",
-                     object->pointer, object->size);
-        print_helper(seq, "  comm \"%s\", pid %d, jiffies %lu\n",
-                     object->comm, object->pid, object->jiffies);
-        print_helper(seq, "  backtrace:\n");
+        seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
+                   object->pointer, object->size);
+        seq_printf(seq, "  comm \"%s\", pid %d, jiffies %lu\n",
+                   object->comm, object->pid, object->jiffies);
+        seq_printf(seq, "  backtrace:\n");
 
         for (i = 0; i < object->trace_len; i++) {
                 void *ptr = (void *)object->trace[i];
-                print_helper(seq, "    [<%p>] %pS\n", ptr, ptr);
+                seq_printf(seq, "    [<%p>] %pS\n", ptr, ptr);
         }
 }
 
@@ -344,7 +319,7 @@ static void dump_object_info(struct kmemleak_object *object)
         trace.nr_entries = object->trace_len;
         trace.entries = object->trace;
 
-        pr_notice("kmemleak: Object 0x%08lx (size %zu):\n",
+        pr_notice("Object 0x%08lx (size %zu):\n",
                   object->tree_node.start, object->size);
         pr_notice("  comm \"%s\", pid %d, jiffies %lu\n",
                   object->comm, object->pid, object->jiffies);
@@ -372,7 +347,7 @@ static struct kmemleak_object *lookup_object(unsigned long ptr, int alias)
                 object = prio_tree_entry(node, struct kmemleak_object,
                                          tree_node);
                 if (!alias && object->pointer != ptr) {
-                        kmemleak_warn("kmemleak: Found object by alias");
+                        kmemleak_warn("Found object by alias");
                         object = NULL;
                 }
         } else
@@ -467,8 +442,7 @@ static void create_object(unsigned long ptr, size_t size, int min_count,
 
         object = kmem_cache_alloc(object_cache, gfp & GFP_KMEMLEAK_MASK);
         if (!object) {
-                kmemleak_stop("kmemleak: Cannot allocate a kmemleak_object "
-                              "structure\n");
+                kmemleak_stop("Cannot allocate a kmemleak_object structure\n");
                 return;
         }
 
@@ -527,8 +501,8 @@ static void create_object(unsigned long ptr, size_t size, int min_count,
         if (node != &object->tree_node) {
                 unsigned long flags;
 
-                kmemleak_stop("kmemleak: Cannot insert 0x%lx into the object "
-                              "search tree (already existing)\n", ptr);
+                kmemleak_stop("Cannot insert 0x%lx into the object search tree "
+                              "(already existing)\n", ptr);
                 object = lookup_object(ptr, 1);
                 spin_lock_irqsave(&object->lock, flags);
                 dump_object_info(object);
@@ -553,8 +527,10 @@ static void delete_object(unsigned long ptr)
         write_lock_irqsave(&kmemleak_lock, flags);
         object = lookup_object(ptr, 0);
         if (!object) {
-                kmemleak_warn("kmemleak: Freeing unknown object at 0x%08lx\n",
+#ifdef DEBUG
+                kmemleak_warn("Freeing unknown object at 0x%08lx\n",
                               ptr);
+#endif
                 write_unlock_irqrestore(&kmemleak_lock, flags);
                 return;
         }
@@ -570,8 +546,6 @@ static void delete_object(unsigned long ptr)
          * cannot be freed when it is being scanned.
          */
         spin_lock_irqsave(&object->lock, flags);
-        if (object->flags & OBJECT_REPORTED)
-                print_referenced(object);
         object->flags &= ~OBJECT_ALLOCATED;
         spin_unlock_irqrestore(&object->lock, flags);
         put_object(object);
@@ -588,8 +562,7 @@ static void make_gray_object(unsigned long ptr)
 
         object = find_and_get_object(ptr, 0);
         if (!object) {
-                kmemleak_warn("kmemleak: Graying unknown object at 0x%08lx\n",
-                              ptr);
+                kmemleak_warn("Graying unknown object at 0x%08lx\n", ptr);
                 return;
         }
 
@@ -610,8 +583,7 @@ static void make_black_object(unsigned long ptr)
 
         object = find_and_get_object(ptr, 0);
         if (!object) {
-                kmemleak_warn("kmemleak: Blacking unknown object at 0x%08lx\n",
-                              ptr);
+                kmemleak_warn("Blacking unknown object at 0x%08lx\n", ptr);
                 return;
         }
 
@@ -634,21 +606,20 @@ static void add_scan_area(unsigned long ptr, unsigned long offset,
 
         object = find_and_get_object(ptr, 0);
         if (!object) {
-                kmemleak_warn("kmemleak: Adding scan area to unknown "
-                              "object at 0x%08lx\n", ptr);
+                kmemleak_warn("Adding scan area to unknown object at 0x%08lx\n",
+                              ptr);
                 return;
         }
 
         area = kmem_cache_alloc(scan_area_cache, gfp & GFP_KMEMLEAK_MASK);
         if (!area) {
-                kmemleak_warn("kmemleak: Cannot allocate a scan area\n");
+                kmemleak_warn("Cannot allocate a scan area\n");
                 goto out;
         }
 
         spin_lock_irqsave(&object->lock, flags);
         if (offset + length > object->size) {
-                kmemleak_warn("kmemleak: Scan area larger than object "
-                              "0x%08lx\n", ptr);
+                kmemleak_warn("Scan area larger than object 0x%08lx\n", ptr);
                 dump_object_info(object);
                 kmem_cache_free(scan_area_cache, area);
                 goto out_unlock;
@@ -677,8 +648,7 @@ static void object_no_scan(unsigned long ptr)
 
         object = find_and_get_object(ptr, 0);
         if (!object) {
-                kmemleak_warn("kmemleak: Not scanning unknown object at "
-                              "0x%08lx\n", ptr);
+                kmemleak_warn("Not scanning unknown object at 0x%08lx\n", ptr);
                 return;
         }
 
@@ -699,7 +669,8 @@ static void log_early(int op_type, const void *ptr, size_t size,
         struct early_log *log;
 
         if (crt_early_log >= ARRAY_SIZE(early_log)) {
-                kmemleak_stop("kmemleak: Early log buffer exceeded\n");
+                pr_warning("Early log buffer exceeded\n");
+                kmemleak_disable();
                 return;
         }
 
@@ -811,21 +782,6 @@ void kmemleak_no_scan(const void *ptr)
 EXPORT_SYMBOL(kmemleak_no_scan);
 
 /*
- * Yield the CPU so that other tasks get a chance to run.  The yielding is
- * rate-limited to avoid excessive number of calls to the schedule() function
- * during memory scanning.
- */
-static void scan_yield(void)
-{
-        might_sleep();
-
-        if (time_is_before_eq_jiffies(next_scan_yield)) {
-                schedule();
-                next_scan_yield = jiffies + jiffies_scan_yield;
-        }
-}
-
-/*
  * Memory scanning is a long process and it needs to be interruptable. This
  * function checks whether such interrupt condition occured.
  */
@@ -865,15 +821,6 @@ static void scan_block(void *_start, void *_end,
                 if (scan_should_stop())
                         break;
 
-                /*
-                 * When scanning a memory block with a corresponding
-                 * kmemleak_object, the CPU yielding is handled in the calling
-                 * code since it holds the object->lock to avoid the block
-                 * freeing.
-                 */
-                if (!scanned)
-                        scan_yield();
-
                 object = find_and_get_object(pointer, 1);
                 if (!object)
                         continue;
@@ -955,6 +902,9 @@ static void kmemleak_scan(void)
         struct kmemleak_object *object, *tmp;
         struct task_struct *task;
         int i;
+        int new_leaks = 0;
+
+        jiffies_last_scan = jiffies;
 
         /* prepare the kmemleak_object's */
         rcu_read_lock();
@@ -966,7 +916,7 @@ static void kmemleak_scan(void)
                  * 1 reference to any object at this point.
                  */
                 if (atomic_read(&object->use_count) > 1) {
-                        pr_debug("kmemleak: object->use_count = %d\n",
+                        pr_debug("object->use_count = %d\n",
                                  atomic_read(&object->use_count));
                         dump_object_info(object);
                 }
@@ -1036,7 +986,7 @@ static void kmemleak_scan(void)
          */
         object = list_entry(gray_list.next, typeof(*object), gray_list);
         while (&object->gray_list != &gray_list) {
-                scan_yield();
+                cond_resched();
 
                 /* may add new objects to the list */
                 if (!scan_should_stop())
@@ -1052,6 +1002,32 @@ static void kmemleak_scan(void)
                 object = tmp;
         }
         WARN_ON(!list_empty(&gray_list));
+
+        /*
+         * If scanning was stopped do not report any new unreferenced objects.
+         */
+        if (scan_should_stop())
+                return;
+
+        /*
+         * Scanning result reporting.
+         */
+        rcu_read_lock();
+        list_for_each_entry_rcu(object, &object_list, object_list) {
+                spin_lock_irqsave(&object->lock, flags);
+                if (unreferenced_object(object) &&
+                    !(object->flags & OBJECT_REPORTED)) {
+                        object->flags |= OBJECT_REPORTED;
+                        new_leaks++;
+                }
+                spin_unlock_irqrestore(&object->lock, flags);
+        }
+        rcu_read_unlock();
+
+        if (new_leaks)
+                pr_info("%d new suspected memory leaks (see "
+                        "/sys/kernel/debug/kmemleak)\n", new_leaks);
+
 }
 
 /*
@@ -1062,7 +1038,7 @@ static int kmemleak_scan_thread(void *arg)
 {
         static int first_run = 1;
 
-        pr_info("kmemleak: Automatic memory scanning thread started\n");
+        pr_info("Automatic memory scanning thread started\n");
 
         /*
          * Wait before the first scan to allow the system to fully initialize.
@@ -1073,49 +1049,25 @@ static int kmemleak_scan_thread(void *arg)
         }
 
         while (!kthread_should_stop()) {
-                struct kmemleak_object *object;
                 signed long timeout = jiffies_scan_wait;
 
                 mutex_lock(&scan_mutex);
-
                 kmemleak_scan();
-                reported_leaks = 0;
-
-                rcu_read_lock();
-                list_for_each_entry_rcu(object, &object_list, object_list) {
-                        unsigned long flags;
-
-                        if (reported_leaks >= REPORTS_NR)
-                                break;
-                        spin_lock_irqsave(&object->lock, flags);
-                        if (!(object->flags & OBJECT_REPORTED) &&
-                            unreferenced_object(object)) {
-                                print_unreferenced(NULL, object);
-                                object->flags |= OBJECT_REPORTED;
-                                reported_leaks++;
-                        } else if ((object->flags & OBJECT_REPORTED) &&
-                                   referenced_object(object)) {
-                                print_referenced(object);
-                                object->flags &= ~OBJECT_REPORTED;
-                        }
-                        spin_unlock_irqrestore(&object->lock, flags);
-                }
-                rcu_read_unlock();
-
                 mutex_unlock(&scan_mutex);
+
                 /* wait before the next scan */
                 while (timeout && !kthread_should_stop())
                         timeout = schedule_timeout_interruptible(timeout);
         }
 
-        pr_info("kmemleak: Automatic memory scanning thread ended\n");
+        pr_info("Automatic memory scanning thread ended\n");
 
         return 0;
 }
 
 /*
  * Start the automatic memory scanning thread. This function must be called
- * with the kmemleak_mutex held.
+ * with the scan_mutex held.
  */
 void start_scan_thread(void)
 {
@@ -1123,14 +1075,14 @@ void start_scan_thread(void)
                 return;
         scan_thread = kthread_run(kmemleak_scan_thread, NULL, "kmemleak");
         if (IS_ERR(scan_thread)) {
-                pr_warning("kmemleak: Failed to create the scan thread\n");
+                pr_warning("Failed to create the scan thread\n");
                 scan_thread = NULL;
         }
 }
 
 /*
  * Stop the automatic memory scanning thread. This function must be called
- * with the kmemleak_mutex held.
+ * with the scan_mutex held.
  */
 void stop_scan_thread(void)
 {
@@ -1150,10 +1102,8 @@ static void *kmemleak_seq_start(struct seq_file *seq, loff_t *pos)
         struct kmemleak_object *object;
         loff_t n = *pos;
 
-        if (!n) {
-                kmemleak_scan();
+        if (!n)
                 reported_leaks = 0;
-        }
         if (reported_leaks >= REPORTS_NR)
                 return NULL;
 
@@ -1214,11 +1164,10 @@ static int kmemleak_seq_show(struct seq_file *seq, void *v)
         unsigned long flags;
 
         spin_lock_irqsave(&object->lock, flags);
-        if (!unreferenced_object(object))
-                goto out;
-        print_unreferenced(seq, object);
-        reported_leaks++;
-out:
+        if ((object->flags & OBJECT_REPORTED) && unreferenced_object(object)) {
+                print_unreferenced(seq, object);
+                reported_leaks++;
+        }
         spin_unlock_irqrestore(&object->lock, flags);
         return 0;
 }
@@ -1237,13 +1186,10 @@ static int kmemleak_open(struct inode *inode, struct file *file)
         if (!atomic_read(&kmemleak_enabled))
                 return -EBUSY;
 
-        ret = mutex_lock_interruptible(&kmemleak_mutex);
+        ret = mutex_lock_interruptible(&scan_mutex);
         if (ret < 0)
                 goto out;
         if (file->f_mode & FMODE_READ) {
-                ret = mutex_lock_interruptible(&scan_mutex);
-                if (ret < 0)
-                        goto kmemleak_unlock;
                 ret = seq_open(file, &kmemleak_seq_ops);
                 if (ret < 0)
                         goto scan_unlock;
@@ -1252,8 +1198,6 @@ static int kmemleak_open(struct inode *inode, struct file *file)
 
 scan_unlock:
         mutex_unlock(&scan_mutex);
-kmemleak_unlock:
-        mutex_unlock(&kmemleak_mutex);
 out:
         return ret;
 }
@@ -1262,11 +1206,9 @@ static int kmemleak_release(struct inode *inode, struct file *file)
 {
         int ret = 0;
 
-        if (file->f_mode & FMODE_READ) {
+        if (file->f_mode & FMODE_READ)
                 seq_release(inode, file);
-                mutex_unlock(&scan_mutex);
-        }
-        mutex_unlock(&kmemleak_mutex);
+        mutex_unlock(&scan_mutex);
 
         return ret;
 }
@@ -1281,6 +1223,7 @@ static int kmemleak_release(struct inode *inode, struct file *file)
  *   scan=off   - stop the automatic memory scanning thread
  *   scan=...   - set the automatic memory scanning period in seconds (0 to
  *                disable it)
+ *   scan       - trigger a memory scan
  */
 static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
                               size_t size, loff_t *ppos)
@@ -1318,7 +1261,9 @@ static ssize_t kmemleak_write(struct file *file, const char __user *user_buf,
                         jiffies_scan_wait = msecs_to_jiffies(secs * 1000);
                         start_scan_thread();
                 }
-        } else
+        } else if (strncmp(buf, "scan", 4) == 0)
+                kmemleak_scan();
+        else
                 return -EINVAL;
 
         /* ignore the rest of the buffer, only one command at a time */
@@ -1343,11 +1288,9 @@ static int kmemleak_cleanup_thread(void *arg)
 {
         struct kmemleak_object *object;
 
-        mutex_lock(&kmemleak_mutex);
+        mutex_lock(&scan_mutex);
         stop_scan_thread();
-        mutex_unlock(&kmemleak_mutex);
 
-        mutex_lock(&scan_mutex);
         rcu_read_lock();
         list_for_each_entry_rcu(object, &object_list, object_list)
                 delete_object(object->pointer);
@@ -1367,7 +1310,7 @@ static void kmemleak_cleanup(void)
         cleanup_thread = kthread_run(kmemleak_cleanup_thread, NULL,
                                      "kmemleak-clean");
         if (IS_ERR(cleanup_thread))
-                pr_warning("kmemleak: Failed to create the clean-up thread\n");
+                pr_warning("Failed to create the clean-up thread\n");
 }
 
 /*
@@ -1414,7 +1357,6 @@ void __init kmemleak_init(void)
         int i;
         unsigned long flags;
 
-        jiffies_scan_yield = msecs_to_jiffies(MSECS_SCAN_YIELD);
         jiffies_min_age = msecs_to_jiffies(MSECS_MIN_AGE);
         jiffies_scan_wait = msecs_to_jiffies(SECS_SCAN_WAIT * 1000);
 
@@ -1488,11 +1430,10 @@ static int __init kmemleak_late_init(void)
         dentry = debugfs_create_file("kmemleak", S_IRUGO, NULL, NULL,
                                      &kmemleak_fops);
         if (!dentry)
-                pr_warning("kmemleak: Failed to create the debugfs kmemleak "
-                           "file\n");
-        mutex_lock(&kmemleak_mutex);
+                pr_warning("Failed to create the debugfs kmemleak file\n");
+        mutex_lock(&scan_mutex);
         start_scan_thread();
-        mutex_unlock(&kmemleak_mutex);
+        mutex_unlock(&scan_mutex);
 
         pr_info("Kernel memory leak detector initialized\n");
 
diff --git a/mm/memory.c b/mm/memory.c
index 98bcb90d5957..65216194eb8d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1207,8 +1207,8 @@ static inline int use_zero_page(struct vm_area_struct *vma)
 
 
 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-                     unsigned long start, int len, int flags,
-                struct page **pages, struct vm_area_struct **vmas)
+                     unsigned long start, int nr_pages, int flags,
+                     struct page **pages, struct vm_area_struct **vmas)
 {
         int i;
         unsigned int vm_flags = 0;
@@ -1217,7 +1217,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
         int ignore = !!(flags & GUP_FLAGS_IGNORE_VMA_PERMISSIONS);
         int ignore_sigkill = !!(flags & GUP_FLAGS_IGNORE_SIGKILL);
 
-        if (len <= 0)
+        if (nr_pages <= 0)
                 return 0;
         /* 
          * Require read or write permissions.
@@ -1269,7 +1269,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                                 vmas[i] = gate_vma;
                         i++;
                         start += PAGE_SIZE;
-                        len--;
+                        nr_pages--;
                         continue;
                 }
 
@@ -1280,7 +1280,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 
                 if (is_vm_hugetlb_page(vma)) {
                         i = follow_hugetlb_page(mm, vma, pages, vmas,
-                                                &start, &len, i, write);
+                                                &start, &nr_pages, i, write);
                         continue;
                 }
 
@@ -1311,8 +1311,10 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                         while (!(page = follow_page(vma, start, foll_flags))) {
                                 int ret;
 
-                                /* FOLL_WRITE matches FAULT_FLAG_WRITE! */
-                                ret = handle_mm_fault(mm, vma, start, foll_flags & FOLL_WRITE);
+                                ret = handle_mm_fault(mm, vma, start,
+                                        (foll_flags & FOLL_WRITE) ?
+                                        FAULT_FLAG_WRITE : 0);
+
                                 if (ret & VM_FAULT_ERROR) {
                                         if (ret & VM_FAULT_OOM)
                                                 return i ? i : -ENOMEM;
@@ -1355,9 +1357,9 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                                 vmas[i] = vma;
                         i++;
                         start += PAGE_SIZE;
-                        len--;
-                } while (len && start < vma->vm_end);
-        } while (len);
+                        nr_pages--;
+                } while (nr_pages && start < vma->vm_end);
+        } while (nr_pages);
         return i;
 }
 
@@ -1366,7 +1368,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  * @tsk:        task_struct of target task
  * @mm:         mm_struct of target mm
  * @start:      starting user address
- * @len:        number of pages from start to pin
+ * @nr_pages:   number of pages from start to pin
  * @write:      whether pages will be written to by the caller
  * @force:      whether to force write access even if user mapping is
  *              readonly. This will result in the page being COWed even
@@ -1378,7 +1380,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  *              Or NULL if the caller does not require them.
  *
  * Returns number of pages pinned. This may be fewer than the number
- * requested. If len is 0 or negative, returns 0. If no pages
+ * requested. If nr_pages is 0 or negative, returns 0. If no pages
  * were pinned, returns -errno. Each page returned must be released
  * with a put_page() call when it is finished with. vmas will only
  * remain valid while mmap_sem is held.
@@ -1412,7 +1414,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
  * See also get_user_pages_fast, for performance critical applications.
  */
 int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-                unsigned long start, int len, int write, int force,
+                unsigned long start, int nr_pages, int write, int force,
                 struct page **pages, struct vm_area_struct **vmas)
 {
         int flags = 0;
@@ -1422,9 +1424,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
         if (force)
                 flags |= GUP_FLAGS_FORCE;
 
-        return __get_user_pages(tsk, mm,
-                                start, len, flags,
-                                pages, vmas);
+        return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
 }
 
 EXPORT_SYMBOL(get_user_pages);
@@ -2517,7 +2517,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
         delayacct_set_flag(DELAYACCT_PF_SWAPIN);
         page = lookup_swap_cache(entry);
         if (!page) {
-                grab_swap_token(); /* Contend for token _before_ read-in */
+                grab_swap_token(mm); /* Contend for token _before_ read-in */
                 page = swapin_readahead(entry,
                                         GFP_HIGHUSER_MOVABLE, vma, address);
                 if (!page) {
diff --git a/mm/nommu.c b/mm/nommu.c
index 2fd2ad5da98e..53cab10fece4 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -173,8 +173,8 @@ unsigned int kobjsize(const void *objp)
 }
 
 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-                     unsigned long start, int len, int flags,
-                struct page **pages, struct vm_area_struct **vmas)
+                     unsigned long start, int nr_pages, int flags,
+                     struct page **pages, struct vm_area_struct **vmas)
 {
         struct vm_area_struct *vma;
         unsigned long vm_flags;
@@ -189,7 +189,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
         vm_flags  = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
         vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
 
-        for (i = 0; i < len; i++) {
+        for (i = 0; i < nr_pages; i++) {
                 vma = find_vma(mm, start);
                 if (!vma)
                         goto finish_or_fault;
@@ -224,7 +224,7 @@ finish_or_fault:
  * - don't permit access to VMAs that don't support it, such as I/O mappings
  */
 int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
-        unsigned long start, int len, int write, int force,
+        unsigned long start, int nr_pages, int write, int force,
         struct page **pages, struct vm_area_struct **vmas)
 {
         int flags = 0;
@@ -234,12 +234,31 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
         if (force)
                 flags |= GUP_FLAGS_FORCE;
 
-        return __get_user_pages(tsk, mm,
-                                start, len, flags,
-                                pages, vmas);
+        return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
 }
 EXPORT_SYMBOL(get_user_pages);
 
+/**
+ * follow_pfn - look up PFN at a user virtual address
+ * @vma: memory mapping
+ * @address: user virtual address
+ * @pfn: location to store found PFN
+ *
+ * Only IO mappings and raw PFN mappings are allowed.
+ *
+ * Returns zero and the pfn at @pfn on success, -ve otherwise.
+ */
+int follow_pfn(struct vm_area_struct *vma, unsigned long address,
+        unsigned long *pfn)
+{
+        if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
+                return -EINVAL;
+
+        *pfn = address >> PAGE_SHIFT;
+        return 0;
+}
+EXPORT_SYMBOL(follow_pfn);
+
 DEFINE_RWLOCK(vmlist_lock);
 struct vm_struct *vmlist;
 
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2c075dcf03d4..3c7f5e1afe5f 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -541,8 +541,11 @@ static void balance_dirty_pages(struct address_space *mapping)
                  * filesystems (i.e. NFS) in which data may have been
                  * written to the server's write cache, but has not yet
                  * been flushed to permanent storage.
+                 * Only move pages to writeback if this bdi is over its
+                 * threshold otherwise wait until the disk writes catch
+                 * up.
                  */
-                if (bdi_nr_reclaimable) {
+                if (bdi_nr_reclaimable > bdi_thresh) {
                         writeback_inodes(&wbc);
                         pages_written += write_chunk - wbc.nr_to_write;
                         get_dirty_limits(&background_thresh, &dirty_thresh,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 30d5093a099d..e0f2cdf9d8b1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1153,10 +1153,10 @@ again:
                          * properly detect and handle allocation failures.
                          *
                          * We most definitely don't want callers attempting to
-                         * allocate greater than single-page units with
+                         * allocate greater than order-1 page units with
                          * __GFP_NOFAIL.
                          */
-                        WARN_ON_ONCE(order > 0);
+                        WARN_ON_ONCE(order > 1);
                 }
                 spin_lock_irqsave(&zone->lock, flags);
                 page = __rmqueue(zone, order, migratetype);
@@ -3026,7 +3026,7 @@ bad:
                 if (dzone == zone)
                         break;
                 kfree(zone_pcp(dzone, cpu));
-                zone_pcp(dzone, cpu) = NULL;
+                zone_pcp(dzone, cpu) = &boot_pageset[cpu];
         }
         return -ENOMEM;
 }
@@ -3041,7 +3041,7 @@ static inline void free_zone_pagesets(int cpu)
                 /* Free per_cpu_pageset if it is slab allocated */
                 if (pset != &boot_pageset[cpu])
                         kfree(pset);
-                zone_pcp(zone, cpu) = NULL;
+                zone_pcp(zone, cpu) = &boot_pageset[cpu];
         }
 }
 
@@ -4032,6 +4032,8 @@ static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
         int i, nid;
         unsigned long usable_startpfn;
         unsigned long kernelcore_node, kernelcore_remaining;
+        /* save the state before borrow the nodemask */
+        nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
         unsigned long totalpages = early_calculate_totalpages();
         int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
 
@@ -4059,7 +4061,7 @@ static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
 
         /* If kernelcore was not specified, there is no ZONE_MOVABLE */
         if (!required_kernelcore)
-                return;
+                goto out;
 
         /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
         find_usable_zone_for_movable();
@@ -4158,6 +4160,10 @@ restart:
         for (nid = 0; nid < MAX_NUMNODES; nid++)
                 zone_movable_pfn[nid] =
                         roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
+
+out:
+        /* restore the node_state */
+        node_states[N_HIGH_MEMORY] = saved_node_state;
 }
 
 /* Any regular memory on that node ? */
@@ -4242,11 +4248,6 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
                                                 early_node_map[i].start_pfn,
                                                 early_node_map[i].end_pfn);
 
-        /*
-         * find_zone_movable_pfns_for_nodes/early_calculate_totalpages init
-         * that node_mask, clear it at first
-         */
-        nodes_clear(node_states[N_HIGH_MEMORY]);
         /* Initialise every node */
         mminit_verify_pageflags_layout();
         setup_nr_node_ids();
@@ -4659,7 +4660,7 @@ int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
         ret = proc_dointvec_minmax(table, write, file, buffer, length, ppos);
         if (!write || (ret == -EINVAL))
                 return ret;
-        for_each_zone(zone) {
+        for_each_populated_zone(zone) {
                 for_each_online_cpu(cpu) {
                         unsigned long  high;
                         high = zone->present_pages / percpu_pagelist_fraction;
diff --git a/mm/shmem.c b/mm/shmem.c
index e89d7ec18eda..d713239ce2ce 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1558,6 +1558,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, int mode,
                 spin_lock_init(&info->lock);
                 info->flags = flags & VM_NORESERVE;
                 INIT_LIST_HEAD(&info->swaplist);
+                cache_no_acl(inode);
 
                 switch (mode & S_IFMT) {
                 default:
@@ -2388,7 +2389,6 @@ static void shmem_destroy_inode(struct inode *inode)
                 /* only struct inode is valid if it's an inline symlink */
                 mpol_free_shared_policy(&SHMEM_I(inode)->policy);
         }
-        shmem_acl_destroy_inode(inode);
         kmem_cache_free(shmem_inode_cachep, SHMEM_I(inode));
 }
 
@@ -2397,10 +2397,6 @@ static void init_once(void *foo)
         struct shmem_inode_info *p = (struct shmem_inode_info *) foo;
 
         inode_init_once(&p->vfs_inode);
-#ifdef CONFIG_TMPFS_POSIX_ACL
-        p->i_acl = NULL;
-        p->i_default_acl = NULL;
-#endif
 }
 
 static int init_inodecache(void)
diff --git a/mm/shmem_acl.c b/mm/shmem_acl.c
index 8e5aadd7dcd6..606a8e757a42 100644
--- a/mm/shmem_acl.c
+++ b/mm/shmem_acl.c
@@ -22,11 +22,11 @@ shmem_get_acl(struct inode *inode, int type)
         spin_lock(&inode->i_lock);
         switch(type) {
                 case ACL_TYPE_ACCESS:
-                        acl = posix_acl_dup(SHMEM_I(inode)->i_acl);
+                        acl = posix_acl_dup(inode->i_acl);
                         break;
 
                 case ACL_TYPE_DEFAULT:
-                        acl = posix_acl_dup(SHMEM_I(inode)->i_default_acl);
+                        acl = posix_acl_dup(inode->i_default_acl);
                         break;
         }
         spin_unlock(&inode->i_lock);
@@ -45,13 +45,13 @@ shmem_set_acl(struct inode *inode, int type, struct posix_acl *acl)
         spin_lock(&inode->i_lock);
         switch(type) {
                 case ACL_TYPE_ACCESS:
-                        free = SHMEM_I(inode)->i_acl;
-                        SHMEM_I(inode)->i_acl = posix_acl_dup(acl);
+                        free = inode->i_acl;
+                        inode->i_acl = posix_acl_dup(acl);
                         break;
 
                 case ACL_TYPE_DEFAULT:
-                        free = SHMEM_I(inode)->i_default_acl;
-                        SHMEM_I(inode)->i_default_acl = posix_acl_dup(acl);
+                        free = inode->i_default_acl;
+                        inode->i_default_acl = posix_acl_dup(acl);
                         break;
         }
         spin_unlock(&inode->i_lock);
@@ -155,23 +155,6 @@ shmem_acl_init(struct inode *inode, struct inode *dir)
 }
 
 /**
- * shmem_acl_destroy_inode  -  destroy acls hanging off the in-memory inode
- *
- * This is done before destroying the actual inode.
- */
-
-void
-shmem_acl_destroy_inode(struct inode *inode)
-{
-        if (SHMEM_I(inode)->i_acl)
-                posix_acl_release(SHMEM_I(inode)->i_acl);
-        SHMEM_I(inode)->i_acl = NULL;
-        if (SHMEM_I(inode)->i_default_acl)
-                posix_acl_release(SHMEM_I(inode)->i_default_acl);
-        SHMEM_I(inode)->i_default_acl = NULL;
-}
-
-/**
  * shmem_check_acl  -  check_acl() callback for generic_permission()
  */
 static int
diff --git a/mm/slub.c b/mm/slub.c
index 23bb79acc4b9..ffc895cc3a68 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1085,11 +1085,17 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
 {
         struct page *page;
         struct kmem_cache_order_objects oo = s->oo;
+        gfp_t alloc_gfp;
 
         flags |= s->allocflags;
 
-        page = alloc_slab_page(flags | __GFP_NOWARN | __GFP_NORETRY, node,
-                                                                        oo);
+        /*
+         * Let the initial higher-order allocation fail under memory pressure
+         * so we fall-back to the minimum order allocation.
+         */
+        alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
+
+        page = alloc_slab_page(alloc_gfp, node, oo);
         if (unlikely(!page)) {
                 oo = s->min;
                 /*
diff --git a/mm/thrash.c b/mm/thrash.c
index c4c5205a9c35..2372d4ed5dd8 100644
--- a/mm/thrash.c
+++ b/mm/thrash.c
@@ -26,47 +26,45 @@ static DEFINE_SPINLOCK(swap_token_lock);
 struct mm_struct *swap_token_mm;
 static unsigned int global_faults;
 
-void grab_swap_token(void)
+void grab_swap_token(struct mm_struct *mm)
 {
         int current_interval;
 
         global_faults++;
 
-        current_interval = global_faults - current->mm->faultstamp;
+        current_interval = global_faults - mm->faultstamp;
 
         if (!spin_trylock(&swap_token_lock))
                 return;
 
         /* First come first served */
         if (swap_token_mm == NULL) {
-                current->mm->token_priority = current->mm->token_priority + 2;
-                swap_token_mm = current->mm;
+                mm->token_priority = mm->token_priority + 2;
+                swap_token_mm = mm;
                 goto out;
         }
 
-        if (current->mm != swap_token_mm) {
-                if (current_interval < current->mm->last_interval)
-                        current->mm->token_priority++;
+        if (mm != swap_token_mm) {
+                if (current_interval < mm->last_interval)
+                        mm->token_priority++;
                 else {
-                        if (likely(current->mm->token_priority > 0))
-                                current->mm->token_priority--;
+                        if (likely(mm->token_priority > 0))
+                                mm->token_priority--;
                 }
                 /* Check if we deserve the token */
-                if (current->mm->token_priority >
-                                swap_token_mm->token_priority) {
-                        current->mm->token_priority += 2;
-                        swap_token_mm = current->mm;
+                if (mm->token_priority > swap_token_mm->token_priority) {
+                        mm->token_priority += 2;
+                        swap_token_mm = mm;
                 }
         } else {
                 /* Token holder came in again! */
-                current->mm->token_priority += 2;
+                mm->token_priority += 2;
         }
 
 out:
-        current->mm->faultstamp = global_faults;
-        current->mm->last_interval = current_interval;
+        mm->faultstamp = global_faults;
+        mm->last_interval = current_interval;
         spin_unlock(&swap_token_lock);
-return;
 }
 
 /* Called on process exit. */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index e8fa2d9eb212..54155268dfca 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -932,7 +932,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
                                 continue;
                         if (__isolate_lru_page(cursor_page, mode, file) == 0) {
                                 list_move(&cursor_page->lru, dst);
-                                mem_cgroup_del_lru(page);
+                                mem_cgroup_del_lru(cursor_page);
                                 nr_taken++;
                                 scan++;
                         }