Merge branch 'akpm' (Andrew's patch bomb)

Merge the emailed seties of 19 patches from Andrew Morton

* akpm:
  rapidio/tsi721: fix queue wrapping bug in inbound doorbell handler
  memcg: fix mapcount check in move charge code for anonymous page
  mm: thp: fix BUG on mm->nr_ptes
  alpha: fix 32/64-bit bug in futex support
  memcg: fix GPF when cgroup removal races with last exit
  debugobjects: Fix selftest for static warnings
  floppy/scsi: fix setting of BIO flags
  memcg: fix deadlock by inverting lrucare nesting
  drivers/rtc/rtc-r9701.c: fix crash in r9701_remove()
  c2port: class_create() returns an ERR_PTR
  pps: class_create() returns an ERR_PTR, not NULL
  hung_task: fix the broken rcu_lock_break() logic
  vfork: kill PF_STARTING
  coredump_wait: don't call complete_vfork_done()
  vfork: make it killable
  vfork: introduce complete_vfork_done()
  aio: wake up waiters when freeing unused kiocbs
  kprobes: return proper error code from register_kprobe()
  kmsg_dump: don't run on non-error paths by default

24 files changed, 156 insertions, 164 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 033d4e69b43b..d99fd9c0ec0e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2211,6 +2211,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
                         default: off.
 
+        printk.always_kmsg_dump=
+                        Trigger kmsg_dump for cases other than kernel oops or
+                        panics
+                        Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
+                        default: disabled
+
         printk.time=    Show timing data prefixed to each printk message line
                         Format: <bool>  (1/Y/y=enable, 0/N/n=disable)
 
diff --git a/arch/alpha/include/asm/futex.h b/arch/alpha/include/asm/futex.h
index e8a761aee088..f939794363ac 100644
--- a/arch/alpha/include/asm/futex.h
+++ b/arch/alpha/include/asm/futex.h
@@ -108,7 +108,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
         "       lda     $31,3b-2b(%0)\n"
         "       .previous\n"
         :       "+r"(ret), "=&r"(prev), "=&r"(cmp)
-        :       "r"(uaddr), "r"((long)oldval), "r"(newval)
+        :       "r"(uaddr), "r"((long)(int)oldval), "r"(newval)
         :       "memory");
 
         *uval = prev;
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 9baf11e86362..744f078f4dd8 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3832,7 +3832,7 @@ static int __floppy_read_block_0(struct block_device *bdev)
         bio.bi_size = size;
         bio.bi_bdev = bdev;
         bio.bi_sector = 0;
-        bio.bi_flags = BIO_QUIET;
+        bio.bi_flags = (1 << BIO_QUIET);
         init_completion(&complete);
         bio.bi_private = &complete;
         bio.bi_end_io = floppy_rb0_complete;
diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
index 19fc7c1cb428..f428d86bfc10 100644
--- a/drivers/misc/c2port/core.c
+++ b/drivers/misc/c2port/core.c
@@ -984,9 +984,9 @@ static int __init c2port_init(void)
                 " - (C) 2007 Rodolfo Giometti\n");
 
         c2port_class = class_create(THIS_MODULE, "c2port");
-        if (!c2port_class) {
+        if (IS_ERR(c2port_class)) {
                 printk(KERN_ERR "c2port: failed to allocate class\n");
-                return -ENOMEM;
+                return PTR_ERR(c2port_class);
         }
         c2port_class->dev_attrs = c2port_attrs;
 
diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c
index 2baadd21b7a6..98fbe62694d4 100644
--- a/drivers/pps/pps.c
+++ b/drivers/pps/pps.c
@@ -369,9 +369,9 @@ static int __init pps_init(void)
         int err;
 
         pps_class = class_create(THIS_MODULE, "pps");
-        if (!pps_class) {
+        if (IS_ERR(pps_class)) {
                 pr_err("failed to allocate class\n");
-                return -ENOMEM;
+                return PTR_ERR(pps_class);
         }
         pps_class->dev_attrs = pps_attrs;
 
diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 691b1ab1a3d0..30d2072f480b 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -410,13 +410,14 @@ static void tsi721_db_dpc(struct work_struct *work)
          */
         mport = priv->mport;
 
-        wr_ptr = ioread32(priv->regs + TSI721_IDQ_WP(IDB_QUEUE));
-        rd_ptr = ioread32(priv->regs + TSI721_IDQ_RP(IDB_QUEUE));
+        wr_ptr = ioread32(priv->regs + TSI721_IDQ_WP(IDB_QUEUE)) % IDB_QSIZE;
+        rd_ptr = ioread32(priv->regs + TSI721_IDQ_RP(IDB_QUEUE)) % IDB_QSIZE;
 
         while (wr_ptr != rd_ptr) {
                 idb_entry = (u64 *)(priv->idb_base +
                                         (TSI721_IDB_ENTRY_SIZE * rd_ptr));
                 rd_ptr++;
+                rd_ptr %= IDB_QSIZE;
                 idb.msg = *idb_entry;
                 *idb_entry = 0;
 
diff --git a/drivers/rtc/rtc-r9701.c b/drivers/rtc/rtc-r9701.c
index 9beba49c3c5b..2853c2a6f10f 100644
--- a/drivers/rtc/rtc-r9701.c
+++ b/drivers/rtc/rtc-r9701.c
@@ -125,6 +125,13 @@ static int __devinit r9701_probe(struct spi_device *spi)
         unsigned char tmp;
         int res;
 
+        tmp = R100CNT;
+        res = read_regs(&spi->dev, &tmp, 1);
+        if (res || tmp != 0x20) {
+                dev_err(&spi->dev, "cannot read RTC register\n");
+                return -ENODEV;
+        }
+
         rtc = rtc_device_register("r9701",
                                 &spi->dev, &r9701_rtc_ops, THIS_MODULE);
         if (IS_ERR(rtc))
@@ -132,13 +139,6 @@ static int __devinit r9701_probe(struct spi_device *spi)
 
         dev_set_drvdata(&spi->dev, rtc);
 
-        tmp = R100CNT;
-        res = read_regs(&spi->dev, &tmp, 1);
-        if (res || tmp != 0x20) {
-                rtc_device_unregister(rtc);
-                return res;
-        }
-
         return 0;
 }
 
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index 0cb39ff21171..f8fb2d691c0a 100644
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -408,7 +408,7 @@ int sd_dif_prepare(struct request *rq, sector_t hw_sector, unsigned int sector_s
                         kunmap_atomic(sdt, KM_USER0);
                 }
 
-                bio->bi_flags |= BIO_MAPPED_INTEGRITY;
+                bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY);
         }
 
         return 0;
diff --git a/fs/aio.c b/fs/aio.c
index 969beb0e2231..67e4b9047cc9 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -490,6 +490,8 @@ static void kiocb_batch_free(struct kioctx *ctx, struct kiocb_batch *batch)
                 kmem_cache_free(kiocb_cachep, req);
                 ctx->reqs_active--;
         }
+        if (unlikely(!ctx->reqs_active && ctx->dead))
+                wake_up_all(&ctx->wait);
         spin_unlock_irq(&ctx->ctx_lock);
 }
 
diff --git a/fs/exec.c b/fs/exec.c
index 92ce83a11e90..153dee14fe55 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1915,7 +1915,6 @@ static int coredump_wait(int exit_code, struct core_state *core_state)
 {
         struct task_struct *tsk = current;
         struct mm_struct *mm = tsk->mm;
-        struct completion *vfork_done;
         int core_waiters = -EBUSY;
 
         init_completion(&core_state->startup);
@@ -1927,22 +1926,9 @@ static int coredump_wait(int exit_code, struct core_state *core_state)
                 core_waiters = zap_threads(tsk, mm, core_state, exit_code);
         up_write(&mm->mmap_sem);
 
-        if (unlikely(core_waiters < 0))
-                goto fail;
-
-        /*
-         * Make sure nobody is waiting for us to release the VM,
-         * otherwise we can deadlock when we wait on each other
-         */
-        vfork_done = tsk->vfork_done;
-        if (vfork_done) {
-                tsk->vfork_done = NULL;
-                complete(vfork_done);
-        }
-
-        if (core_waiters)
+        if (core_waiters > 0)
                 wait_for_completion(&core_state->startup);
-fail:
+
         return core_waiters;
 }
 
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index fee66317e071..35f7237ec972 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -15,13 +15,18 @@
 #include <linux/errno.h>
 #include <linux/list.h>
 
+/*
+ * Keep this list arranged in rough order of priority. Anything listed after
+ * KMSG_DUMP_OOPS will not be logged by default unless printk.always_kmsg_dump
+ * is passed to the kernel.
+ */
 enum kmsg_dump_reason {
-        KMSG_DUMP_OOPS,
         KMSG_DUMP_PANIC,
+        KMSG_DUMP_OOPS,
+        KMSG_DUMP_EMERG,
         KMSG_DUMP_RESTART,
         KMSG_DUMP_HALT,
         KMSG_DUMP_POWEROFF,
-        KMSG_DUMP_EMERG,
 };
 
 /**
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 4d34356fe644..b80de520670b 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -129,7 +129,6 @@ extern void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
 extern void mem_cgroup_replace_page_cache(struct page *oldpage,
                                         struct page *newpage);
 
-extern void mem_cgroup_reset_owner(struct page *page);
 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
 extern int do_swap_account;
 #endif
@@ -392,10 +391,6 @@ static inline void mem_cgroup_replace_page_cache(struct page *oldpage,
                                 struct page *newpage)
 {
 }
-
-static inline void mem_cgroup_reset_owner(struct page *page)
-{
-}
 #endif /* CONFIG_CGROUP_MEM_CONT */
 
 #if !defined(CONFIG_CGROUP_MEM_RES_CTLR) || !defined(CONFIG_DEBUG_VM)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7d379a6bfd88..0657368bd78f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1777,7 +1777,6 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *
 /*
  * Per process flags
  */
-#define PF_STARTING     0x00000002      /* being created */
 #define PF_EXITING      0x00000004      /* getting shut down */
 #define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
 #define PF_VCPU         0x00000010      /* I'm a virtual CPU */
@@ -2371,7 +2370,7 @@ static inline int thread_group_empty(struct task_struct *p)
  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
  * pins the final release of task.io_context.  Also protects ->cpuset and
- * ->cgroup.subsys[].
+ * ->cgroup.subsys[]. And ->vfork_done.
  *
  * Nests both inside and outside of read_lock(&tasklist_lock).
  * It must not be nested with write_lock_irq(&tasklist_lock),
diff --git a/kernel/fork.c b/kernel/fork.c
index e2cd3e2a5ae8..26a7a6707fa7 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -668,6 +668,38 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
         return mm;
 }
 
+static void complete_vfork_done(struct task_struct *tsk)
+{
+        struct completion *vfork;
+
+        task_lock(tsk);
+        vfork = tsk->vfork_done;
+        if (likely(vfork)) {
+                tsk->vfork_done = NULL;
+                complete(vfork);
+        }
+        task_unlock(tsk);
+}
+
+static int wait_for_vfork_done(struct task_struct *child,
+                                struct completion *vfork)
+{
+        int killed;
+
+        freezer_do_not_count();
+        killed = wait_for_completion_killable(vfork);
+        freezer_count();
+
+        if (killed) {
+                task_lock(child);
+                child->vfork_done = NULL;
+                task_unlock(child);
+        }
+
+        put_task_struct(child);
+        return killed;
+}
+
 /* Please note the differences between mmput and mm_release.
  * mmput is called whenever we stop holding onto a mm_struct,
  * error success whatever.
@@ -683,8 +715,6 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
  */
 void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 {
-        struct completion *vfork_done = tsk->vfork_done;
-
         /* Get rid of any futexes when releasing the mm */
 #ifdef CONFIG_FUTEX
         if (unlikely(tsk->robust_list)) {
@@ -704,17 +734,15 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
         /* Get rid of any cached register state */
         deactivate_mm(tsk, mm);
 
-        /* notify parent sleeping on vfork() */
-        if (vfork_done) {
-                tsk->vfork_done = NULL;
-                complete(vfork_done);
-        }
+        if (tsk->vfork_done)
+                complete_vfork_done(tsk);
 
         /*
          * If we're exiting normally, clear a user-space tid field if
          * requested.  We leave this alone when dying by signal, to leave
          * the value intact in a core dump, and to save the unnecessary
-         * trouble otherwise.  Userland only wants this done for a sys_exit.
+         * trouble, say, a killed vfork parent shouldn't touch this mm.
+         * Userland only wants this done for a sys_exit.
          */
         if (tsk->clear_child_tid) {
                 if (!(tsk->flags & PF_SIGNALED) &&
@@ -1018,7 +1046,6 @@ static void copy_flags(unsigned long clone_flags, struct task_struct *p)
 
         new_flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
         new_flags |= PF_FORKNOEXEC;
-        new_flags |= PF_STARTING;
         p->flags = new_flags;
 }
 
@@ -1548,16 +1575,9 @@ long do_fork(unsigned long clone_flags,
                 if (clone_flags & CLONE_VFORK) {
                         p->vfork_done = &vfork;
                         init_completion(&vfork);
+                        get_task_struct(p);
                 }
 
-                /*
-                 * We set PF_STARTING at creation in case tracing wants to
-                 * use this to distinguish a fully live task from one that
-                 * hasn't finished SIGSTOP raising yet.  Now we clear it
-                 * and set the child going.
-                 */
-                p->flags &= ~PF_STARTING;
-
                 wake_up_new_task(p);
 
                 /* forking complete and child started to run, tell ptracer */
@@ -1565,10 +1585,8 @@ long do_fork(unsigned long clone_flags,
                         ptrace_event(trace, nr);
 
                 if (clone_flags & CLONE_VFORK) {
-                        freezer_do_not_count();
-                        wait_for_completion(&vfork);
-                        freezer_count();
-                        ptrace_event(PTRACE_EVENT_VFORK_DONE, nr);
+                        if (!wait_for_vfork_done(p, &vfork))
+                                ptrace_event(PTRACE_EVENT_VFORK_DONE, nr);
                 }
         } else {
                 nr = PTR_ERR(p);
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 2e48ec0c2e91..c21449f85a2a 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -119,15 +119,20 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
  * For preemptible RCU it is sufficient to call rcu_read_unlock in order
  * to exit the grace period. For classic RCU, a reschedule is required.
  */
-static void rcu_lock_break(struct task_struct *g, struct task_struct *t)
+static bool rcu_lock_break(struct task_struct *g, struct task_struct *t)
 {
+        bool can_cont;
+
         get_task_struct(g);
         get_task_struct(t);
         rcu_read_unlock();
         cond_resched();
         rcu_read_lock();
+        can_cont = pid_alive(g) && pid_alive(t);
         put_task_struct(t);
         put_task_struct(g);
+
+        return can_cont;
 }
 
 /*
@@ -154,9 +159,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
                         goto unlock;
                 if (!--batch_count) {
                         batch_count = HUNG_TASK_BATCHING;
-                        rcu_lock_break(g, t);
-                        /* Exit if t or g was unhashed during refresh. */
-                        if (t->state == TASK_DEAD || g->state == TASK_DEAD)
+                        if (!rcu_lock_break(g, t))
                                 goto unlock;
                 }
                 /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 9788c0ec6f43..c62b8546cc90 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1334,8 +1334,10 @@ int __kprobes register_kprobe(struct kprobe *p)
         if (!kernel_text_address((unsigned long) p->addr) ||
             in_kprobes_functions((unsigned long) p->addr) ||
             ftrace_text_reserved(p->addr, p->addr) ||
-            jump_label_text_reserved(p->addr, p->addr))
-                goto fail_with_jump_label;
+            jump_label_text_reserved(p->addr, p->addr)) {
+                ret = -EINVAL;
+                goto cannot_probe;
+        }
 
         /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
         p->flags &= KPROBE_FLAG_DISABLED;
@@ -1352,7 +1354,7 @@ int __kprobes register_kprobe(struct kprobe *p)
                  * its code to prohibit unexpected unloading.
                  */
                 if (unlikely(!try_module_get(probed_mod)))
-                        goto fail_with_jump_label;
+                        goto cannot_probe;
 
                 /*
                  * If the module freed .init.text, we couldn't insert
@@ -1361,7 +1363,7 @@ int __kprobes register_kprobe(struct kprobe *p)
                 if (within_module_init((unsigned long)p->addr, probed_mod) &&
                     probed_mod->state != MODULE_STATE_COMING) {
                         module_put(probed_mod);
-                        goto fail_with_jump_label;
+                        goto cannot_probe;
                 }
                 /* ret will be updated by following code */
         }
@@ -1409,7 +1411,7 @@ out:
 
         return ret;
 
-fail_with_jump_label:
+cannot_probe:
         preempt_enable();
         jump_label_unlock();
         return ret;
diff --git a/kernel/printk.c b/kernel/printk.c
index 13c0a1143f49..32690a0b7a18 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -702,6 +702,9 @@ static bool printk_time = 0;
 #endif
 module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
 
+static bool always_kmsg_dump;
+module_param_named(always_kmsg_dump, always_kmsg_dump, bool, S_IRUGO | S_IWUSR);
+
 /* Check if we have any console registered that can be called early in boot. */
 static int have_callable_console(void)
 {
@@ -1732,6 +1735,9 @@ void kmsg_dump(enum kmsg_dump_reason reason)
         unsigned long l1, l2;
         unsigned long flags;
 
+        if ((reason > KMSG_DUMP_OOPS) && !always_kmsg_dump)
+                return;
+
         /* Theoretically, the log could move on after we do this, but
            there's not a lot we can do about that. The new messages
            will overwrite the start of what we dump. */
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 77cb245f8e7b..0ab9ae8057f0 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -818,17 +818,9 @@ static int __init fixup_activate(void *addr, enum debug_obj_state state)
                 if (obj->static_init == 1) {
                         debug_object_init(obj, &descr_type_test);
                         debug_object_activate(obj, &descr_type_test);
-                        /*
-                         * Real code should return 0 here ! This is
-                         * not a fixup of some bad behaviour. We
-                         * merily call the debug_init function to keep
-                         * track of the object.
-                         */
-                        return 1;
-                } else {
-                        /* Real code needs to emit a warning here */
+                        return 0;
                 }
-                return 0;
+                return 1;
 
         case ODEBUG_STATE_ACTIVE:
                 debug_object_deactivate(obj, &descr_type_test);
@@ -967,7 +959,7 @@ static void __init debug_objects_selftest(void)
 
         obj.static_init = 1;
         debug_object_activate(&obj, &descr_type_test);
-        if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, warnings))
+        if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
                 goto out;
         debug_object_init(&obj, &descr_type_test);
         if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 91d3efb25d15..8f7fc394f636 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -671,6 +671,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
                 set_pmd_at(mm, haddr, pmd, entry);
                 prepare_pmd_huge_pte(pgtable, mm);
                 add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
+                mm->nr_ptes++;
                 spin_unlock(&mm->page_table_lock);
         }
 
@@ -789,6 +790,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
         pmd = pmd_mkold(pmd_wrprotect(pmd));
         set_pmd_at(dst_mm, addr, dst_pmd, pmd);
         prepare_pmd_huge_pte(pgtable, dst_mm);
+        dst_mm->nr_ptes++;
 
         ret = 0;
 out_unlock:
@@ -887,7 +889,6 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
         }
         kfree(pages);
 
-        mm->nr_ptes++;
         smp_wmb(); /* make pte visible before pmd */
         pmd_populate(mm, pmd, pgtable);
         page_remove_rmap(page);
@@ -1047,6 +1048,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
                         VM_BUG_ON(page_mapcount(page) < 0);
                         add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
                         VM_BUG_ON(!PageHead(page));
+                        tlb->mm->nr_ptes--;
                         spin_unlock(&tlb->mm->page_table_lock);
                         tlb_remove_page(tlb, page);
                         pte_free(tlb->mm, pgtable);
@@ -1375,7 +1377,6 @@ static int __split_huge_page_map(struct page *page,
                         pte_unmap(pte);
                 }
 
-                mm->nr_ptes++;
                 smp_wmb(); /* make pte visible before pmd */
                 /*
                  * Up to this point the pmd is present and huge and
@@ -1988,7 +1989,6 @@ static void collapse_huge_page(struct mm_struct *mm,
         set_pmd_at(mm, address, pmd, _pmd);
         update_mmu_cache(vma, address, _pmd);
         prepare_pmd_huge_pte(pgtable, mm);
-        mm->nr_ptes--;
         spin_unlock(&mm->page_table_lock);
 
 #ifndef CONFIG_NUMA
diff --git a/mm/ksm.c b/mm/ksm.c
index 1925ffbfb27f..310544a379ae 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -28,7 +28,6 @@
 #include <linux/kthread.h>
 #include <linux/wait.h>
 #include <linux/slab.h>
-#include <linux/memcontrol.h>
 #include <linux/rbtree.h>
 #include <linux/memory.h>
 #include <linux/mmu_notifier.h>
@@ -1572,16 +1571,6 @@ struct page *ksm_does_need_to_copy(struct page *page,
 
         new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
         if (new_page) {
-                /*
-                 * The memcg-specific accounting when moving
-                 * pages around the LRU lists relies on the
-                 * page's owner (memcg) to be valid.  Usually,
-                 * pages are assigned to a new owner before
-                 * being put on the LRU list, but since this
-                 * is not the case here, the stale owner from
-                 * a previous allocation cycle must be reset.
-                 */
-                mem_cgroup_reset_owner(new_page);
                 copy_user_highpage(new_page, page, address, vma);
 
                 SetPageDirty(new_page);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 228d6461c12a..5585dc3d3646 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1042,6 +1042,19 @@ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page,
 
         pc = lookup_page_cgroup(page);
         memcg = pc->mem_cgroup;
+
+        /*
+         * Surreptitiously switch any uncharged page to root:
+         * an uncharged page off lru does nothing to secure
+         * its former mem_cgroup from sudden removal.
+         *
+         * Our caller holds lru_lock, and PageCgroupUsed is updated
+         * under page_cgroup lock: between them, they make all uses
+         * of pc->mem_cgroup safe.
+         */
+        if (!PageCgroupUsed(pc) && memcg != root_mem_cgroup)
+                pc->mem_cgroup = memcg = root_mem_cgroup;
+
         mz = page_cgroup_zoneinfo(memcg, page);
         /* compound_order() is stabilized through lru_lock */
         MEM_CGROUP_ZSTAT(mz, lru) += 1 << compound_order(page);
@@ -2408,8 +2421,12 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
                                        struct page *page,
                                        unsigned int nr_pages,
                                        struct page_cgroup *pc,
-                                       enum charge_type ctype)
+                                       enum charge_type ctype,
+                                       bool lrucare)
 {
+        struct zone *uninitialized_var(zone);
+        bool was_on_lru = false;
+
         lock_page_cgroup(pc);
         if (unlikely(PageCgroupUsed(pc))) {
                 unlock_page_cgroup(pc);
@@ -2420,6 +2437,21 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
          * we don't need page_cgroup_lock about tail pages, becase they are not
          * accessed by any other context at this point.
          */
+
+        /*
+         * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page
+         * may already be on some other mem_cgroup's LRU.  Take care of it.
+         */
+        if (lrucare) {
+                zone = page_zone(page);
+                spin_lock_irq(&zone->lru_lock);
+                if (PageLRU(page)) {
+                        ClearPageLRU(page);
+                        del_page_from_lru_list(zone, page, page_lru(page));
+                        was_on_lru = true;
+                }
+        }
+
         pc->mem_cgroup = memcg;
         /*
          * We access a page_cgroup asynchronously without lock_page_cgroup().
@@ -2443,9 +2475,18 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
                 break;
         }
 
+        if (lrucare) {
+                if (was_on_lru) {
+                        VM_BUG_ON(PageLRU(page));
+                        SetPageLRU(page);
+                        add_page_to_lru_list(zone, page, page_lru(page));
+                }
+                spin_unlock_irq(&zone->lru_lock);
+        }
+
         mem_cgroup_charge_statistics(memcg, PageCgroupCache(pc), nr_pages);
         unlock_page_cgroup(pc);
-        WARN_ON_ONCE(PageLRU(page));
+
         /*
          * "charge_statistics" updated event counter. Then, check it.
          * Insert ancestor (and ancestor's ancestors), to softlimit RB-tree.
@@ -2643,7 +2684,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
         ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom);
         if (ret == -ENOMEM)
                 return ret;
-        __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype);
+        __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype, false);
         return 0;
 }
 
@@ -2663,35 +2704,6 @@ static void
 __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr,
                                         enum charge_type ctype);
 
-static void
-__mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg,
-                                        enum charge_type ctype)
-{
-        struct page_cgroup *pc = lookup_page_cgroup(page);
-        struct zone *zone = page_zone(page);
-        unsigned long flags;
-        bool removed = false;
-
-        /*
-         * In some case, SwapCache, FUSE(splice_buf->radixtree), the page
-         * is already on LRU. It means the page may on some other page_cgroup's
-         * LRU. Take care of it.
-         */
-        spin_lock_irqsave(&zone->lru_lock, flags);
-        if (PageLRU(page)) {
-                del_page_from_lru_list(zone, page, page_lru(page));
-                ClearPageLRU(page);
-                removed = true;
-        }
-        __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
-        if (removed) {
-                add_page_to_lru_list(zone, page, page_lru(page));
-                SetPageLRU(page);
-        }
-        spin_unlock_irqrestore(&zone->lru_lock, flags);
-        return;
-}
-
 int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
                                 gfp_t gfp_mask)
 {
@@ -2769,13 +2781,16 @@ static void
 __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
                                         enum charge_type ctype)
 {
+        struct page_cgroup *pc;
+
         if (mem_cgroup_disabled())
                 return;
         if (!memcg)
                 return;
         cgroup_exclude_rmdir(&memcg->css);
 
-        __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
+        pc = lookup_page_cgroup(page);
+        __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype, true);
         /*
          * Now swap is on-memory. This means this page may be
          * counted both as mem and swap....double count.
@@ -3027,23 +3042,6 @@ void mem_cgroup_uncharge_end(void)
         batch->memcg = NULL;
 }
 
-/*
- * A function for resetting pc->mem_cgroup for newly allocated pages.
- * This function should be called if the newpage will be added to LRU
- * before start accounting.
- */
-void mem_cgroup_reset_owner(struct page *newpage)
-{
-        struct page_cgroup *pc;
-
-        if (mem_cgroup_disabled())
-                return;
-
-        pc = lookup_page_cgroup(newpage);
-        VM_BUG_ON(PageCgroupUsed(pc));
-        pc->mem_cgroup = root_mem_cgroup;
-}
-
 #ifdef CONFIG_SWAP
 /*
  * called after __delete_from_swap_cache() and drop "page" account.
@@ -3248,7 +3246,7 @@ int mem_cgroup_prepare_migration(struct page *page,
                 ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
         else
                 ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
-        __mem_cgroup_commit_charge(memcg, newpage, 1, pc, ctype);
+        __mem_cgroup_commit_charge(memcg, newpage, 1, pc, ctype, false);
         return ret;
 }
 
@@ -3332,7 +3330,7 @@ void mem_cgroup_replace_page_cache(struct page *oldpage,
          * the newpage may be on LRU(or pagevec for LRU) already. We lock
          * LRU while we overwrite pc->mem_cgroup.
          */
-        __mem_cgroup_commit_charge_lrucare(newpage, memcg, type);
+        __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type, true);
 }
 
 #ifdef CONFIG_DEBUG_VM
@@ -5077,7 +5075,7 @@ static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
                 return NULL;
         if (PageAnon(page)) {
                 /* we don't move shared anon */
-                if (!move_anon() || page_mapcount(page) > 2)
+                if (!move_anon() || page_mapcount(page) > 1)
                         return NULL;
         } else if (!move_file())
                 /* we ignore mapcount for file pages */
diff --git a/mm/migrate.c b/mm/migrate.c
index df141f60289e..1503b6b54ecb 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -839,8 +839,6 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
         if (!newpage)
                 return -ENOMEM;
 
-        mem_cgroup_reset_owner(newpage);
-
         if (page_count(page) == 1) {
                 /* page was freed from under us. So we are done. */
                 goto out;
diff --git a/mm/swap.c b/mm/swap.c
index fff1ff7fb9ad..14380e9fbe33 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -652,7 +652,7 @@ EXPORT_SYMBOL(__pagevec_release);
 void lru_add_page_tail(struct zone* zone,
                        struct page *page, struct page *page_tail)
 {
-        int active;
+        int uninitialized_var(active);
         enum lru_list lru;
         const int file = 0;
 
@@ -672,7 +672,6 @@ void lru_add_page_tail(struct zone* zone,
                         active = 0;
                         lru = LRU_INACTIVE_ANON;
                 }
-                update_page_reclaim_stat(zone, page_tail, file, active);
         } else {
                 SetPageUnevictable(page_tail);
                 lru = LRU_UNEVICTABLE;
@@ -693,6 +692,9 @@ void lru_add_page_tail(struct zone* zone,
                 list_head = page_tail->lru.prev;
                 list_move_tail(&page_tail->lru, list_head);
         }
+
+        if (!PageUnevictable(page))
+                update_page_reclaim_stat(zone, page_tail, file, active);
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
@@ -710,8 +712,8 @@ static void __pagevec_lru_add_fn(struct page *page, void *arg)
         SetPageLRU(page);
         if (active)
                 SetPageActive(page);
-        update_page_reclaim_stat(zone, page, file, active);
         add_page_to_lru_list(zone, page, lru);
+        update_page_reclaim_stat(zone, page, file, active);
 }
 
 /*
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 470038a91873..ea6b32d61873 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -300,16 +300,6 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
                         new_page = alloc_page_vma(gfp_mask, vma, addr);
                         if (!new_page)
                                 break;          /* Out of memory */
-                        /*
-                         * The memcg-specific accounting when moving
-                         * pages around the LRU lists relies on the
-                         * page's owner (memcg) to be valid.  Usually,
-                         * pages are assigned to a new owner before
-                         * being put on the LRU list, but since this
-                         * is not the case here, the stale owner from
-                         * a previous allocation cycle must be reset.
-                         */
-                        mem_cgroup_reset_owner(new_page);
                 }
 
                 /*