Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6

52 files changed, 1135 insertions, 674 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 0b5ff083fa2..353d3fe8ba3 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -43,7 +43,7 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
 obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
 obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
 obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
-obj-$(CONFIG_USE_GENERIC_SMP_HELPERS) += smp.o
+obj-$(CONFIG_SMP) += smp.o
 ifneq ($(CONFIG_SMP),y)
 obj-y += up.o
 endif
@@ -100,6 +100,7 @@ obj-$(CONFIG_FUNCTION_TRACER) += trace/
 obj-$(CONFIG_TRACING) += trace/
 obj-$(CONFIG_X86_DS) += trace/
 obj-$(CONFIG_RING_BUFFER) += trace/
+obj-$(CONFIG_TRACEPOINTS) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
 obj-$(CONFIG_IRQ_WORK) += irq_work.o
 obj-$(CONFIG_PERF_EVENTS) += perf_event.o
@@ -121,7 +122,7 @@ $(obj)/configs.o: $(obj)/config_data.h
 # config_data.h contains the same information as ikconfig.h but gzipped.
 # Info from config_data can be extracted from /proc/config*
 targets += config_data.gz
-$(obj)/config_data.gz: .config FORCE
+$(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE
 	$(call if_changed,gzip)
 
 quiet_cmd_ikconfiggz = IKCFG   $@
diff --git a/kernel/audit.c b/kernel/audit.c
index 77770a034d5..e4956244ae5 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -400,7 +400,7 @@ static void kauditd_send_skb(struct sk_buff *skb)
 	if (err < 0) {
 		BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
 		printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
-		audit_log_lost("auditd dissapeared\n");
+		audit_log_lost("auditd disappeared\n");
 		audit_pid = 0;
 		/* we might get lucky and get this in the next auditd */
 		audit_hold_skb(skb);
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 51cddc11cd8..b24d7027b83 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -763,9 +763,8 @@ EXPORT_SYMBOL_GPL(cgroup_unlock);
  * -> cgroup_mkdir.
  */
 
-static struct dentry *cgroup_lookup(struct inode *dir,
-			struct dentry *dentry, struct nameidata *nd);
 static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode);
+static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *);
 static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
 static int cgroup_populate_dir(struct cgroup *cgrp);
 static const struct inode_operations cgroup_dir_inode_operations;
@@ -862,6 +861,11 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
 	iput(inode);
 }
 
+static int cgroup_delete(const struct dentry *d)
+{
+	return 1;
+}
+
 static void remove_dir(struct dentry *d)
 {
 	struct dentry *parent = dget(d->d_parent);
@@ -912,7 +916,7 @@ static void cgroup_d_remove_dir(struct dentry *dentry)
 
 	parent = dentry->d_parent;
 	spin_lock(&parent->d_lock);
-	spin_lock(&dentry->d_lock);
+	spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
 	list_del_init(&dentry->d_u.d_child);
 	spin_unlock(&dentry->d_lock);
 	spin_unlock(&parent->d_lock);
@@ -1451,6 +1455,11 @@ static int cgroup_set_super(struct super_block *sb, void *data)
 
 static int cgroup_get_rootdir(struct super_block *sb)
 {
+	static const struct dentry_operations cgroup_dops = {
+		.d_iput = cgroup_diput,
+		.d_delete = cgroup_delete,
+	};
+
 	struct inode *inode =
 		cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb);
 	struct dentry *dentry;
@@ -1468,6 +1477,8 @@ static int cgroup_get_rootdir(struct super_block *sb)
 		return -ENOMEM;
 	}
 	sb->s_root = dentry;
+	/* for everything else we want ->d_op set */
+	sb->s_d_op = &cgroup_dops;
 	return 0;
 }
 
@@ -2197,6 +2208,14 @@ static const struct inode_operations cgroup_dir_inode_operations = {
 	.rename = cgroup_rename,
 };
 
+static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+	if (dentry->d_name.len > NAME_MAX)
+		return ERR_PTR(-ENAMETOOLONG);
+	d_add(dentry, NULL);
+	return NULL;
+}
+
 /*
  * Check if a file is a control file
  */
@@ -2207,26 +2226,6 @@ static inline struct cftype *__file_cft(struct file *file)
 	return __d_cft(file->f_dentry);
 }
 
-static int cgroup_delete_dentry(const struct dentry *dentry)
-{
-	return 1;
-}
-
-static struct dentry *cgroup_lookup(struct inode *dir,
-			struct dentry *dentry, struct nameidata *nd)
-{
-	static const struct dentry_operations cgroup_dentry_operations = {
-		.d_delete = cgroup_delete_dentry,
-		.d_iput = cgroup_diput,
-	};
-
-	if (dentry->d_name.len > NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
-	d_set_d_op(dentry, &cgroup_dentry_operations);
-	d_add(dentry, NULL);
-	return NULL;
-}
-
 static int cgroup_create_file(struct dentry *dentry, mode_t mode,
 				struct super_block *sb)
 {
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index a6e72976682..bd3e8e29caa 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2914,7 +2914,7 @@ static void __init kdb_cmd_init(void)
 	}
 }
 
-/* Intialize kdb_printf, breakpoint tables and kdb state */
+/* Initialize kdb_printf, breakpoint tables and kdb state */
 void __init kdb_init(int lvl)
 {
 	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
diff --git a/kernel/exit.c b/kernel/exit.c
index 89c74861a3d..f9a45ebcc7b 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -994,6 +994,15 @@ NORET_TYPE void do_exit(long code)
 	exit_fs(tsk);
 	check_stack_usage();
 	exit_thread();
+
+	/*
+	 * Flush inherited counters to the parent - before the parent
+	 * gets woken up by child-exit notifications.
+	 *
+	 * because of cgroup mode, must be called before cgroup_exit()
+	 */
+	perf_event_exit_task(tsk);
+
 	cgroup_exit(tsk, 1);
 
 	if (group_dead)
@@ -1007,11 +1016,6 @@ NORET_TYPE void do_exit(long code)
 	 * FIXME: do that only when needed, using sched_exit tracepoint
 	 */
 	flush_ptrace_hw_breakpoint(tsk);
-	/*
-	 * Flush inherited counters to the parent - before the parent
-	 * gets woken up by child-exit notifications.
-	 */
-	perf_event_exit_task(tsk);
 
 	exit_notify(tsk, group_dead);
 #ifdef CONFIG_NUMA
diff --git a/kernel/fork.c b/kernel/fork.c
index d9b44f20b6b..25e429152dd 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -66,6 +66,7 @@
 #include <linux/posix-timers.h>
 #include <linux/user-return-notifier.h>
 #include <linux/oom.h>
+#include <linux/khugepaged.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -330,6 +331,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 	retval = ksm_fork(mm, oldmm);
 	if (retval)
 		goto out;
+	retval = khugepaged_fork(mm, oldmm);
+	if (retval)
+		goto out;
 
 	prev = NULL;
 	for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
@@ -529,6 +533,9 @@ void __mmdrop(struct mm_struct *mm)
 	mm_free_pgd(mm);
 	destroy_context(mm);
 	mmu_notifier_mm_destroy(mm);
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	VM_BUG_ON(mm->pmd_huge_pte);
+#endif
 	free_mm(mm);
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
@@ -543,6 +550,7 @@ void mmput(struct mm_struct *mm)
 	if (atomic_dec_and_test(&mm->mm_users)) {
 		exit_aio(mm);
 		ksm_exit(mm);
+		khugepaged_exit(mm); /* must run before exit_mmap */
 		exit_mmap(mm);
 		set_mm_exe_file(mm, NULL);
 		if (!list_empty(&mm->mmlist)) {
@@ -669,6 +677,10 @@ struct mm_struct *dup_mm(struct task_struct *tsk)
 	mm->token_priority = 0;
 	mm->last_interval = 0;
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	mm->pmd_huge_pte = NULL;
+#endif
+
 	if (!mm_init(mm, tsk))
 		goto fail_nomem;
 
@@ -910,6 +922,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 
 	sig->oom_adj = current->signal->oom_adj;
 	sig->oom_score_adj = current->signal->oom_score_adj;
+	sig->oom_score_adj_min = current->signal->oom_score_adj_min;
 
 	mutex_init(&sig->cred_guard_mutex);
 
@@ -1410,23 +1423,6 @@ long do_fork(unsigned long clone_flags,
 	}
 
 	/*
-	 * We hope to recycle these flags after 2.6.26
-	 */
-	if (unlikely(clone_flags & CLONE_STOPPED)) {
-		static int __read_mostly count = 100;
-
-		if (count > 0 && printk_ratelimit()) {
-			char comm[TASK_COMM_LEN];
-
-			count--;
-			printk(KERN_INFO "fork(): process `%s' used deprecated "
-					"clone flags 0x%lx\n",
-				get_task_comm(comm, current),
-				clone_flags & CLONE_STOPPED);
-		}
-	}
-
-	/*
 	 * When called from kernel_thread, don't do user tracing stuff.
 	 */
 	if (likely(user_mode(regs)))
@@ -1464,16 +1460,7 @@ long do_fork(unsigned long clone_flags,
 		 */
 		p->flags &= ~PF_STARTING;
 
-		if (unlikely(clone_flags & CLONE_STOPPED)) {
-			/*
-			 * We'll start up with an immediate SIGSTOP.
-			 */
-			sigaddset(&p->pending.signal, SIGSTOP);
-			set_tsk_thread_flag(p, TIF_SIGPENDING);
-			__set_task_state(p, TASK_STOPPED);
-		} else {
-			wake_up_new_task(p, clone_flags);
-		}
+		wake_up_new_task(p, clone_flags);
 
 		tracehook_report_clone_complete(trace, regs,
 						clone_flags, nr, p);
diff --git a/kernel/freezer.c b/kernel/freezer.c
index bd1d42b17cb..66ecd2ead21 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -104,8 +104,13 @@ bool freeze_task(struct task_struct *p, bool sig_only)
 	}
 
 	if (should_send_signal(p)) {
-		if (!signal_pending(p))
-			fake_signal_wake_up(p);
+		fake_signal_wake_up(p);
+		/*
+		 * fake_signal_wake_up() goes through p's scheduler
+		 * lock and guarantees that TASK_STOPPED/TRACED ->
+		 * TASK_RUNNING transition can't race with task state
+		 * testing in try_to_freeze_tasks().
+		 */
 	} else if (sig_only) {
 		return false;
 	} else {
diff --git a/kernel/futex.c b/kernel/futex.c
index 3019b92e691..b766d28accd 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -233,7 +233,7 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key)
 {
 	unsigned long address = (unsigned long)uaddr;
 	struct mm_struct *mm = current->mm;
-	struct page *page;
+	struct page *page, *page_head;
 	int err;
 
 	/*
@@ -265,11 +265,46 @@ again:
 	if (err < 0)
 		return err;
 
-	page = compound_head(page);
-	lock_page(page);
-	if (!page->mapping) {
-		unlock_page(page);
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	page_head = page;
+	if (unlikely(PageTail(page))) {
 		put_page(page);
+		/* serialize against __split_huge_page_splitting() */
+		local_irq_disable();
+		if (likely(__get_user_pages_fast(address, 1, 1, &page) == 1)) {
+			page_head = compound_head(page);
+			/*
+			 * page_head is valid pointer but we must pin
+			 * it before taking the PG_lock and/or
+			 * PG_compound_lock. The moment we re-enable
+			 * irqs __split_huge_page_splitting() can
+			 * return and the head page can be freed from
+			 * under us. We can't take the PG_lock and/or
+			 * PG_compound_lock on a page that could be
+			 * freed from under us.
+			 */
+			if (page != page_head) {
+				get_page(page_head);
+				put_page(page);
+			}
+			local_irq_enable();
+		} else {
+			local_irq_enable();
+			goto again;
+		}
+	}
+#else
+	page_head = compound_head(page);
+	if (page != page_head) {
+		get_page(page_head);
+		put_page(page);
+	}
+#endif
+
+	lock_page(page_head);
+	if (!page_head->mapping) {
+		unlock_page(page_head);
+		put_page(page_head);
 		goto again;
 	}
 
@@ -280,20 +315,20 @@ again:
 	 * it's a read-only handle, it's expected that futexes attach to
 	 * the object not the particular process.
 	 */
-	if (PageAnon(page)) {
+	if (PageAnon(page_head)) {
 		key->both.offset |= FUT_OFF_MMSHARED; /* ref taken on mm */
 		key->private.mm = mm;
 		key->private.address = address;
 	} else {
 		key->both.offset |= FUT_OFF_INODE; /* inode-based key */
-		key->shared.inode = page->mapping->host;
-		key->shared.pgoff = page->index;
+		key->shared.inode = page_head->mapping->host;
+		key->shared.pgoff = page_head->index;
 	}
 
 	get_futex_key_refs(key);
 
-	unlock_page(page);
-	put_page(page);
+	unlock_page(page_head);
+	put_page(page_head);
 	return 0;
 }
 
@@ -791,10 +826,9 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
 	new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
 
 	/*
-	 * This happens when we have stolen the lock and the original
-	 * pending owner did not enqueue itself back on the rt_mutex.
-	 * Thats not a tragedy. We know that way, that a lock waiter
-	 * is on the fly. We make the futex_q waiter the pending owner.
+	 * It is possible that the next waiter (the one that brought
+	 * this owner to the kernel) timed out and is no longer
+	 * waiting on the lock.
 	 */
 	if (!new_owner)
 		new_owner = this->task;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 45da2b6920a..0c8d7c04861 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1745,7 +1745,7 @@ schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
 	}
 
 	/*
-	 * A NULL parameter means "inifinte"
+	 * A NULL parameter means "infinite"
 	 */
 	if (!expires) {
 		schedule();
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 31d766bf5d2..8e42fec7686 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -9,9 +9,6 @@ menu "IRQ subsystem"
 config GENERIC_HARDIRQS
        def_bool y
 
-config GENERIC_HARDIRQS_NO__DO_IRQ
-       def_bool y
-
 # Select this to disable the deprecated stuff
 config GENERIC_HARDIRQS_NO_DEPRECATED
        def_bool n
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index e2347eb6330..3540a719012 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -118,114 +118,3 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 
 	return retval;
 }
-
-#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
-
-#ifdef CONFIG_ENABLE_WARN_DEPRECATED
-# warning __do_IRQ is deprecated. Please convert to proper flow handlers
-#endif
-
-/**
- * __do_IRQ - original all in one highlevel IRQ handler
- * @irq:	the interrupt number
- *
- * __do_IRQ handles all normal device IRQ's (the special
- * SMP cross-CPU interrupts have their own specific
- * handlers).
- *
- * This is the original x86 implementation which is used for every
- * interrupt type.
- */
-unsigned int __do_IRQ(unsigned int irq)
-{
-	struct irq_desc *desc = irq_to_desc(irq);
-	struct irqaction *action;
-	unsigned int status;
-
-	kstat_incr_irqs_this_cpu(irq, desc);
-
-	if (CHECK_IRQ_PER_CPU(desc->status)) {
-		irqreturn_t action_ret;
-
-		/*
-		 * No locking required for CPU-local interrupts:
-		 */
-		if (desc->irq_data.chip->ack)
-			desc->irq_data.chip->ack(irq);
-		if (likely(!(desc->status & IRQ_DISABLED))) {
-			action_ret = handle_IRQ_event(irq, desc->action);
-			if (!noirqdebug)
-				note_interrupt(irq, desc, action_ret);
-		}
-		desc->irq_data.chip->end(irq);
-		return 1;
-	}
-
-	raw_spin_lock(&desc->lock);
-	if (desc->irq_data.chip->ack)
-		desc->irq_data.chip->ack(irq);
-	/*
-	 * REPLAY is when Linux resends an IRQ that was dropped earlier
-	 * WAITING is used by probe to mark irqs that are being tested
-	 */
-	status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
-	status |= IRQ_PENDING; /* we _want_ to handle it */
-
-	/*
-	 * If the IRQ is disabled for whatever reason, we cannot
-	 * use the action we have.
-	 */
-	action = NULL;
-	if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
-		action = desc->action;
-		status &= ~IRQ_PENDING; /* we commit to handling */
-		status |= IRQ_INPROGRESS; /* we are handling it */
-	}
-	desc->status = status;
-
-	/*
-	 * If there is no IRQ handler or it was disabled, exit early.
-	 * Since we set PENDING, if another processor is handling
-	 * a different instance of this same irq, the other processor
-	 * will take care of it.
-	 */
-	if (unlikely(!action))
-		goto out;
-
-	/*
-	 * Edge triggered interrupts need to remember
-	 * pending events.
-	 * This applies to any hw interrupts that allow a second
-	 * instance of the same irq to arrive while we are in do_IRQ
-	 * or in the handler. But the code here only handles the _second_
-	 * instance of the irq, not the third or fourth. So it is mostly
-	 * useful for irq hardware that does not mask cleanly in an
-	 * SMP environment.
-	 */
-	for (;;) {
-		irqreturn_t action_ret;
-
-		raw_spin_unlock(&desc->lock);
-
-		action_ret = handle_IRQ_event(irq, action);
-		if (!noirqdebug)
-			note_interrupt(irq, desc, action_ret);
-
-		raw_spin_lock(&desc->lock);
-		if (likely(!(desc->status & IRQ_PENDING)))
-			break;
-		desc->status &= ~IRQ_PENDING;
-	}
-	desc->status &= ~IRQ_INPROGRESS;
-
-out:
-	/*
-	 * The ->end() handler has to deal with interrupts which got
-	 * disabled while the handler was running.
-	 */
-	desc->irq_data.chip->end(irq);
-	raw_spin_unlock(&desc->lock);
-
-	return 1;
-}
-#endif
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 9988d03797f..282f20230e6 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -72,6 +72,8 @@ static inline int desc_node(struct irq_desc *desc) { return 0; }
 
 static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
 {
+	int cpu;
+
 	desc->irq_data.irq = irq;
 	desc->irq_data.chip = &no_irq_chip;
 	desc->irq_data.chip_data = NULL;
@@ -83,7 +85,8 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
 	desc->irq_count = 0;
 	desc->irqs_unhandled = 0;
 	desc->name = NULL;
-	memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
+	for_each_possible_cpu(cpu)
+		*per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
 	desc_smp_init(desc, node);
 }
 
@@ -133,8 +136,7 @@ static struct irq_desc *alloc_desc(int irq, int node)
 	if (!desc)
 		return NULL;
 	/* allocate based on nr_cpu_ids */
-	desc->kstat_irqs = kzalloc_node(nr_cpu_ids * sizeof(*desc->kstat_irqs),
-					 gfp, node);
+	desc->kstat_irqs = alloc_percpu(unsigned int);
 	if (!desc->kstat_irqs)
 		goto err_desc;
 
@@ -149,7 +151,7 @@ static struct irq_desc *alloc_desc(int irq, int node)
 	return desc;
 
 err_kstat:
-	kfree(desc->kstat_irqs);
+	free_percpu(desc->kstat_irqs);
 err_desc:
 	kfree(desc);
 	return NULL;
@@ -166,7 +168,7 @@ static void free_desc(unsigned int irq)
 	mutex_unlock(&sparse_irq_lock);
 
 	free_masks(desc);
-	kfree(desc->kstat_irqs);
+	free_percpu(desc->kstat_irqs);
 	kfree(desc);
 }
 
@@ -234,7 +236,6 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
 	}
 };
 
-static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS];
 int __init early_irq_init(void)
 {
 	int count, i, node = first_online_node;
@@ -250,7 +251,8 @@ int __init early_irq_init(void)
 	for (i = 0; i < count; i++) {
 		desc[i].irq_data.irq = i;
 		desc[i].irq_data.chip = &no_irq_chip;
-		desc[i].kstat_irqs = kstat_irqs_all[i];
+		/* TODO : do this allocation on-demand ... */
+		desc[i].kstat_irqs = alloc_percpu(unsigned int);
 		alloc_masks(desc + i, GFP_KERNEL, node);
 		desc_smp_init(desc + i, node);
 		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
@@ -275,6 +277,22 @@ static void free_desc(unsigned int irq)
 
 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node)
 {
+#if defined(CONFIG_KSTAT_IRQS_ONDEMAND)
+	struct irq_desc *desc;
+	unsigned int i;
+
+	for (i = 0; i < cnt; i++) {
+		desc = irq_to_desc(start + i);
+		if (desc && !desc->kstat_irqs) {
+			unsigned int __percpu *stats = alloc_percpu(unsigned int);
+
+			if (!stats)
+				return -1;
+			if (cmpxchg(&desc->kstat_irqs, NULL, stats) != NULL)
+				free_percpu(stats);
+		}
+	}
+#endif
 	return start;
 }
 #endif /* !CONFIG_SPARSE_IRQ */
@@ -391,7 +409,9 @@ void dynamic_irq_cleanup(unsigned int irq)
 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	return desc ? desc->kstat_irqs[cpu] : 0;
+
+	return desc && desc->kstat_irqs ?
+			*per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
 }
 
 #ifdef CONFIG_GENERIC_HARDIRQS
@@ -401,10 +421,10 @@ unsigned int kstat_irqs(unsigned int irq)
 	int cpu;
 	int sum = 0;
 
-	if (!desc)
+	if (!desc || !desc->kstat_irqs)
 		return 0;
 	for_each_possible_cpu(cpu)
-		sum += desc->kstat_irqs[cpu];
+		sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
 	return sum;
 }
 #endif /* CONFIG_GENERIC_HARDIRQS */
diff --git a/kernel/kexec.c b/kernel/kexec.c
index b55045bc756..ec19b92c7eb 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -163,7 +163,7 @@ static int do_kimage_alloc(struct kimage **rimage, unsigned long entry,
 	 * just verifies it is an address we can use.
 	 *
 	 * Since the kernel does everything in page size chunks ensure
-	 * the destination addreses are page aligned.  Too many
+	 * the destination addresses are page aligned.  Too many
 	 * special cases crop of when we don't do this.  The most
 	 * insidious is getting overlapping destination addresses
 	 * simply because addresses are changed to page size
diff --git a/kernel/latencytop.c b/kernel/latencytop.c
index 17110a4a4fc..ee74b