10 files changed, 410 insertions, 47 deletions

diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 681c52dbfe22..4dd5b1edac98 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -3,3 +3,4 @@ obj-y := handle.o manage.o spurious.o resend.o chip.o devres.o
 obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
+obj-$(CONFIG_NUMA_MIGRATE_IRQ_DESC) += numa_migrate.o
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
index cc0f7321b8ce..650ce4102a63 100644
--- a/kernel/irq/autoprobe.c
+++ b/kernel/irq/autoprobe.c
@@ -40,6 +40,9 @@ unsigned long probe_irq_on(void)
          * flush such a longstanding irq before considering it as spurious.
          */
         for_each_irq_desc_reverse(i, desc) {
+                if (!desc)
+                        continue;
+
                 spin_lock_irq(&desc->lock);
                 if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
                         /*
@@ -68,6 +71,9 @@ unsigned long probe_irq_on(void)
          * happened in the previous stage, it may have masked itself)
          */
         for_each_irq_desc_reverse(i, desc) {
+                if (!desc)
+                        continue;
+
                 spin_lock_irq(&desc->lock);
                 if (!desc->action && !(desc->status & IRQ_NOPROBE)) {
                         desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
@@ -86,6 +92,9 @@ unsigned long probe_irq_on(void)
          * Now filter out any obviously spurious interrupts
          */
         for_each_irq_desc(i, desc) {
+                if (!desc)
+                        continue;
+
                 spin_lock_irq(&desc->lock);
                 status = desc->status;
 
@@ -124,6 +133,9 @@ unsigned int probe_irq_mask(unsigned long val)
         int i;
 
         for_each_irq_desc(i, desc) {
+                if (!desc)
+                        continue;
+
                 spin_lock_irq(&desc->lock);
                 status = desc->status;
 
@@ -166,6 +178,9 @@ int probe_irq_off(unsigned long val)
         unsigned int status;
 
         for_each_irq_desc(i, desc) {
+                if (!desc)
+                        continue;
+
                 spin_lock_irq(&desc->lock);
                 status = desc->status;
 
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 10b5092e9bfe..6eb3c7952b64 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -24,9 +24,10 @@
  */
 void dynamic_irq_init(unsigned int irq)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
         unsigned long flags;
 
+        desc = irq_to_desc(irq);
         if (!desc) {
                 WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
                 return;
@@ -124,6 +125,7 @@ int set_irq_type(unsigned int irq, unsigned int type)
                 return -ENODEV;
         }
 
+        type &= IRQ_TYPE_SENSE_MASK;
         if (type == IRQ_TYPE_NONE)
                 return 0;
 
@@ -352,6 +354,7 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
 
         spin_lock(&desc->lock);
         mask_ack_irq(desc, irq);
+        desc = irq_remap_to_desc(irq, desc);
 
         if (unlikely(desc->status & IRQ_INPROGRESS))
                 goto out_unlock;
@@ -429,6 +432,7 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
         desc->status &= ~IRQ_INPROGRESS;
 out:
         desc->chip->eoi(irq);
+        desc = irq_remap_to_desc(irq, desc);
 
         spin_unlock(&desc->lock);
 }
@@ -465,12 +469,14 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
                     !desc->action)) {
                 desc->status |= (IRQ_PENDING | IRQ_MASKED);
                 mask_ack_irq(desc, irq);
+                desc = irq_remap_to_desc(irq, desc);
                 goto out_unlock;
         }
         kstat_incr_irqs_this_cpu(irq, desc);
 
         /* Start handling the irq */
         desc->chip->ack(irq);
+        desc = irq_remap_to_desc(irq, desc);
 
         /* Mark the IRQ currently in progress.*/
         desc->status |= IRQ_INPROGRESS;
@@ -531,8 +537,10 @@ handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
         if (!noirqdebug)
                 note_interrupt(irq, desc, action_ret);
 
-        if (desc->chip->eoi)
+        if (desc->chip->eoi) {
                 desc->chip->eoi(irq);
+                desc = irq_remap_to_desc(irq, desc);
+        }
 }
 
 void
@@ -567,8 +575,10 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 
         /* Uninstall? */
         if (handle == handle_bad_irq) {
-                if (desc->chip != &no_irq_chip)
+                if (desc->chip != &no_irq_chip) {
                         mask_ack_irq(desc, irq);
+                        desc = irq_remap_to_desc(irq, desc);
+                }
                 desc->status |= IRQ_DISABLED;
                 desc->depth = 1;
         }
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index c815b42d0f5b..6492400cb50d 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -15,9 +15,16 @@
 #include <linux/random.h>
 #include <linux/interrupt.h>
 #include <linux/kernel_stat.h>
+#include <linux/rculist.h>
+#include <linux/hash.h>
 
 #include "internals.h"
 
+/*
+ * lockdep: we want to handle all irq_desc locks as a single lock-class:
+ */
+struct lock_class_key irq_desc_lock_class;
+
 /**
  * handle_bad_irq - handle spurious and unhandled irqs
  * @irq:       the interrupt number
@@ -49,6 +56,155 @@ void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
 int nr_irqs = NR_IRQS;
 EXPORT_SYMBOL_GPL(nr_irqs);
 
+void __init __attribute__((weak)) arch_early_irq_init(void)
+{
+}
+
+#ifdef CONFIG_SPARSE_IRQ
+static struct irq_desc irq_desc_init = {
+        .irq        = -1,
+        .status     = IRQ_DISABLED,
+        .chip       = &no_irq_chip,
+        .handle_irq = handle_bad_irq,
+        .depth      = 1,
+        .lock       = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+        .affinity   = CPU_MASK_ALL
+#endif
+};
+
+void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
+{
+        unsigned long bytes;
+        char *ptr;
+        int node;
+
+        /* Compute how many bytes we need per irq and allocate them */
+        bytes = nr * sizeof(unsigned int);
+
+        node = cpu_to_node(cpu);
+        ptr = kzalloc_node(bytes, GFP_ATOMIC, node);
+        printk(KERN_DEBUG "  alloc kstat_irqs on cpu %d node %d\n", cpu, node);
+
+        if (ptr)
+                desc->kstat_irqs = (unsigned int *)ptr;
+}
+
+void __attribute__((weak)) arch_init_chip_data(struct irq_desc *desc, int cpu)
+{
+}
+
+static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
+{
+        memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
+        desc->irq = irq;
+#ifdef CONFIG_SMP
+        desc->cpu = cpu;
+#endif
+        lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+        init_kstat_irqs(desc, cpu, nr_cpu_ids);
+        if (!desc->kstat_irqs) {
+                printk(KERN_ERR "can not alloc kstat_irqs\n");
+                BUG_ON(1);
+        }
+        arch_init_chip_data(desc, cpu);
+}
+
+/*
+ * Protect the sparse_irqs:
+ */
+DEFINE_SPINLOCK(sparse_irq_lock);
+
+struct irq_desc *irq_desc_ptrs[NR_IRQS] __read_mostly;
+
+static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
+        [0 ... NR_IRQS_LEGACY-1] = {
+                .irq        = -1,
+                .status     = IRQ_DISABLED,
+                .chip       = &no_irq_chip,
+                .handle_irq = handle_bad_irq,
+                .depth      = 1,
+                .lock       = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+                .affinity   = CPU_MASK_ALL
+#endif
+        }
+};
+
+/* FIXME: use bootmem alloc ...*/
+static unsigned int kstat_irqs_legacy[NR_IRQS_LEGACY][NR_CPUS];
+
+void __init early_irq_init(void)
+{
+        struct irq_desc *desc;
+        int legacy_count;
+        int i;
+
+        desc = irq_desc_legacy;
+        legacy_count = ARRAY_SIZE(irq_desc_legacy);
+
+        for (i = 0; i < legacy_count; i++) {
+                desc[i].irq = i;
+                desc[i].kstat_irqs = kstat_irqs_legacy[i];
+
+                irq_desc_ptrs[i] = desc + i;
+        }
+
+        for (i = legacy_count; i < NR_IRQS; i++)
+                irq_desc_ptrs[i] = NULL;
+
+        arch_early_irq_init();
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+        return (irq < NR_IRQS) ? irq_desc_ptrs[irq] : NULL;
+}
+
+struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
+{
+        struct irq_desc *desc;
+        unsigned long flags;
+        int node;
+
+        if (irq >= NR_IRQS) {
+                printk(KERN_WARNING "irq >= NR_IRQS in irq_to_desc_alloc: %d %d\n",
+                                irq, NR_IRQS);
+                WARN_ON(1);
+                return NULL;
+        }
+
+        desc = irq_desc_ptrs[irq];
+        if (desc)
+                return desc;
+
+        spin_lock_irqsave(&sparse_irq_lock, flags);
+
+        /* We have to check it to avoid races with another CPU */
+        desc = irq_desc_ptrs[irq];
+        if (desc)
+                goto out_unlock;
+
+        node = cpu_to_node(cpu);
+        desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
+        printk(KERN_DEBUG "  alloc irq_desc for %d on cpu %d node %d\n",
+                 irq, cpu, node);
+        if (!desc) {
+                printk(KERN_ERR "can not alloc irq_desc\n");
+                BUG_ON(1);
+        }
+        init_one_irq_desc(irq, desc, cpu);
+
+        irq_desc_ptrs[irq] = desc;
+
+out_unlock:
+        spin_unlock_irqrestore(&sparse_irq_lock, flags);
+
+        return desc;
+}
+
+#else
+
 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
         [0 ... NR_IRQS-1] = {
                 .status = IRQ_DISABLED,
@@ -62,6 +218,8 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
         }
 };
 
+#endif
+
 /*
  * What should we do if we get a hw irq event on an illegal vector?
  * Each architecture has to answer this themself.
@@ -179,8 +337,11 @@ unsigned int __do_IRQ(unsigned int irq)
                 /*
                  * No locking required for CPU-local interrupts:
                  */
-                if (desc->chip->ack)
+                if (desc->chip->ack) {
                         desc->chip->ack(irq);
+                        /* get new one */
+                        desc = irq_remap_to_desc(irq, desc);
+                }
                 if (likely(!(desc->status & IRQ_DISABLED))) {
                         action_ret = handle_IRQ_event(irq, desc->action);
                         if (!noirqdebug)
@@ -191,8 +352,10 @@ unsigned int __do_IRQ(unsigned int irq)
         }
 
         spin_lock(&desc->lock);
-        if (desc->chip->ack)
+        if (desc->chip->ack) {
                 desc->chip->ack(irq);
+                desc = irq_remap_to_desc(irq, desc);
+        }
         /*
          * REPLAY is when Linux resends an IRQ that was dropped earlier
          * WAITING is used by probe to mark irqs that are being tested
@@ -259,19 +422,25 @@ out:
 }
 #endif
 
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-/*
- * lockdep: we want to handle all irq_desc locks as a single lock-class:
- */
-static struct lock_class_key irq_desc_lock_class;
-
 void early_init_irq_lock_class(void)
 {
         struct irq_desc *desc;
         int i;
 
-        for_each_irq_desc(i, desc)
+        for_each_irq_desc(i, desc) {
+                if (!desc)
+                        continue;
+
                 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+        }
+}
+
+#ifdef CONFIG_SPARSE_IRQ
+unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        return desc->kstat_irqs[cpu];
 }
 #endif
+EXPORT_SYMBOL(kstat_irqs_cpu);
+
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index c9767e641980..e6d0a43cc125 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -13,6 +13,11 @@ extern void compat_irq_chip_set_default_handler(struct irq_desc *desc);
 extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                 unsigned long flags);
 
+extern struct lock_class_key irq_desc_lock_class;
+extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
+extern spinlock_t sparse_irq_lock;
+extern struct irq_desc *irq_desc_ptrs[NR_IRQS];
+
 #ifdef CONFIG_PROC_FS
 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
 extern void register_handler_proc(unsigned int irq, struct irqaction *action);
@@ -25,6 +30,8 @@ static inline void unregister_handler_proc(unsigned int irq,
                                            struct irqaction *action) { }
 #endif
 
+extern int irq_select_affinity_usr(unsigned int irq);
+
 /*
  * Debugging printout:
  */
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index c498a1b8c621..46953a06f4a8 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -82,24 +82,27 @@ int irq_can_set_affinity(unsigned int irq)
 int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
 {
         struct irq_desc *desc = irq_to_desc(irq);
+        unsigned long flags;
 
         if (!desc->chip->set_affinity)
                 return -EINVAL;
 
+        spin_lock_irqsave(&desc->lock, flags);
+
 #ifdef CONFIG_GENERIC_PENDING_IRQ
         if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) {
-                unsigned long flags;
-
-                spin_lock_irqsave(&desc->lock, flags);
                 desc->affinity = cpumask;
                 desc->chip->set_affinity(irq, cpumask);
-                spin_unlock_irqrestore(&desc->lock, flags);
-        } else
-                set_pending_irq(irq, cpumask);
+        } else {
+                desc->status |= IRQ_MOVE_PENDING;
+                desc->pending_mask = cpumask;
+        }
 #else
         desc->affinity = cpumask;
         desc->chip->set_affinity(irq, cpumask);
 #endif
+        desc->status |= IRQ_AFFINITY_SET;
+        spin_unlock_irqrestore(&desc->lock, flags);
         return 0;
 }
 
@@ -107,24 +110,59 @@ int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
 /*
  * Generic version of the affinity autoselector.
  */
-int irq_select_affinity(unsigned int irq)
+int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
 {
         cpumask_t mask;
-        struct irq_desc *desc;
 
         if (!irq_can_set_affinity(irq))
                 return 0;
 
         cpus_and(mask, cpu_online_map, irq_default_affinity);
 
-        desc = irq_to_desc(irq);
+        /*
+         * Preserve an userspace affinity setup, but make sure that
+         * one of the targets is online.
+         */
+        if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) {
+                if (cpus_intersects(desc->affinity, cpu_online_map))
+                        mask = desc->affinity;
+                else
+                        desc->status &= ~IRQ_AFFINITY_SET;
+        }
+
         desc->affinity = mask;
         desc->chip->set_affinity(irq, mask);
 
         return 0;
 }
+#else
+static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d)
+{
+        return irq_select_affinity(irq);
+}
 #endif
 
+/*
+ * Called when affinity is set via /proc/irq
+ */
+int irq_select_affinity_usr(unsigned int irq)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        unsigned long flags;
+        int ret;
+
+        spin_lock_irqsave(&desc->lock, flags);
+        ret = do_irq_select_affinity(irq, desc);
+        spin_unlock_irqrestore(&desc->lock, flags);
+
+        return ret;
+}
+
+#else
+static inline int do_irq_select_affinity(int irq, struct irq_desc *desc)
+{
+        return 0;
+}
 #endif
 
 /**
@@ -327,21 +365,23 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                  * IRQF_TRIGGER_* but the PIC does not support multiple
                  * flow-types?
                  */
-                pr_warning("No set_type function for IRQ %d (%s)\n", irq,
+                pr_debug("No set_type function for IRQ %d (%s)\n", irq,
                                 chip ? (chip->name ? : "unknown") : "unknown");
                 return 0;
         }
 
-        ret = chip->set_type(irq, flags & IRQF_TRIGGER_MASK);
+        /* caller masked out all except trigger mode flags */
+        ret = chip->set_type(irq, flags);
 
         if (ret)
                 pr_err("setting trigger mode %d for irq %u failed (%pF)\n",
-                                (int)(flags & IRQF_TRIGGER_MASK),
-                                irq, chip->set_type);
+                                (int)flags, irq, chip->set_type);
         else {
+                if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
+                        flags |= IRQ_LEVEL;
                 /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */
-                desc->status &= ~IRQ_TYPE_SENSE_MASK;
-                desc->status |= flags & IRQ_TYPE_SENSE_MASK;
+                desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK);
+                desc->status |= flags;
         }
 
         return ret;
@@ -421,7 +461,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 
                 /* Setup the type (level, edge polarity) if configured: */
                 if (new->flags & IRQF_TRIGGER_MASK) {
-                        ret = __irq_set_trigger(desc, irq, new->flags);
+                        ret = __irq_set_trigger(desc, irq,
+                                        new->flags & IRQF_TRIGGER_MASK);
 
                         if (ret) {
                                 spin_unlock_irqrestore(&desc->lock, flags);
@@ -445,8 +486,12 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
                         /* Undo nested disables: */
                         desc->depth = 1;
 
+                /* Exclude IRQ from balancing if requested */
+                if (new->flags & IRQF_NOBALANCING)
+                        desc->status |= IRQ_NO_BALANCING;
+
                 /* Set default affinity mask once everything is setup */
-                irq_select_affinity(irq);
+                do_irq_select_affinity(irq, desc);
 
         } else if ((new->flags & IRQF_TRIGGER_MASK)
                         && (new->flags & IRQF_TRIGGER_MASK)
@@ -459,10 +504,6 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 
         *p = new;
 
-        /* Exclude IRQ from balancing */
-        if (new->flags & IRQF_NOBALANCING)
-                desc->status |= IRQ_NO_BALANCING;
-
         /* Reset broken irq detection when installing new handler */
         desc->irq_count = 0;
         desc->irqs_unhandled = 0;
diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c
index 90b920d3f52b..9db681d95814 100644
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -1,17 +1,6 @@
 
 #include <linux/irq.h>
 
-void set_pending_irq(unsigned int irq, cpumask_t mask)
-{
-        struct irq_desc *desc = irq_to_desc(irq);
-        unsigned long flags;
-
-        spin_lock_irqsave(&desc->lock, flags);
-        desc->status |= IRQ_MOVE_PENDING;
-        desc->pending_mask = mask;
-        spin_unlock_irqrestore(&desc->lock, flags);
-}
-
 void move_masked_irq(int irq)
 {
         struct irq_desc *desc = irq_to_desc(irq);
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
new file mode 100644
index 000000000000..089c3746358a
--- /dev/null
+++ b/kernel/irq/numa_migrate.c
@@ -0,0 +1,122 @@
+/*
+ * NUMA irq-desc migration code
+ *
+ * Migrate IRQ data structures (irq_desc, chip_data, etc.) over to
+ * the new "home node" of the IRQ.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include "internals.h"
+
+static void init_copy_kstat_irqs(struct irq_desc *old_desc,
+                                 struct irq_desc *desc,
+                                 int cpu, int nr)
+{
+        unsigned long bytes;
+
+        init_kstat_irqs(desc, cpu, nr);
+
+        if (desc->kstat_irqs != old_desc->kstat_irqs) {
+                /* Compute how many bytes we need per irq and allocate them */
+                bytes = nr * sizeof(unsigned int);
+
+                memcpy(desc->kstat_irqs, old_desc->kstat_irqs, bytes);
+        }
+}
+
+static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
+{
+        if (old_desc->kstat_irqs == desc->kstat_irqs)
+                return;
+
+        kfree(old_desc->kstat_irqs);
+        old_desc->kstat_irqs = NULL;
+}
+
+static void init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
+                 struct irq_desc *desc, int cpu)
+{
+        memcpy(desc, old_desc, sizeof(struct irq_desc));
+        desc->cpu = cpu;
+        lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+        init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
+        arch_init_copy_chip_data(old_desc, desc, cpu);
+}
+
+static void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
+{
+        free_kstat_irqs(old_desc, desc);
+        arch_free_chip_data(old_desc, desc);
+}
+
+static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
+                                                int cpu)
+{
+        struct irq_desc *desc;
+        unsigned int irq;
+        unsigned long flags;
+        int node;
+
+        irq = old_desc->irq;
+
+        spin_lock_irqsave(&sparse_irq_lock, flags);
+
+        /* We have to check it to avoid races with another CPU */
+        desc = irq_desc_ptrs[irq];
+
+        if (desc && old_desc != desc)
+                        goto out_unlock;
+
+        node = cpu_to_node(cpu);
+        desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
+        printk(KERN_DEBUG "  move irq_desc for %d to cpu %d node %d\n",
+                 irq, cpu, node);
+        if (!desc) {
+                printk(KERN_ERR "can not get new irq_desc for moving\n");
+                /* still use old one */
+                desc = old_desc;
+                goto out_unlock;
+        }
+        init_copy_one_irq_desc(irq, old_desc, desc, cpu);
+
+        irq_desc_ptrs[irq] = desc;
+
+        /* free the old one */
+        free_one_irq_desc(old_desc, desc);
+        kfree(old_desc);
+
+out_unlock:
+        spin_unlock_irqrestore(&sparse_irq_lock, flags);
+
+        return desc;
+}
+
+struct irq_desc *move_irq_desc(struct irq_desc *desc, int cpu)
+{
+        int old_cpu;
+        int node, old_node;
+
+        /* those all static, do move them */
+        if (desc->irq < NR_IRQS_LEGACY)
+                return desc;
+
+        old_cpu = desc->cpu;
+        printk(KERN_DEBUG
+                 "try to move irq_desc from cpu %d to %d\n", old_cpu, cpu);
+        if (old_cpu != cpu) {
+                node = cpu_to_node(cpu);
+                old_node = cpu_to_node(old_cpu);
+                if (old_node != node)
+                        desc = __real_move_irq_desc(desc, cpu);
+                else
+                        desc->cpu = cpu;
+        }
+
+        return desc;
+}
+
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 4d161c70ba55..f6b3440f05bc 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -62,7 +62,7 @@ static ssize_t irq_affinity_proc_write(struct file *file,
         if (!cpus_intersects(new_value, cpu_online_map))
                 /* Special case for empty set - allow the architecture
                    code to set default SMP affinity. */
-                return irq_select_affinity(irq) ? -EINVAL : count;
+                return irq_select_affinity_usr(irq) ? -EINVAL : count;
 
         irq_set_affinity(irq, new_value);
 
@@ -243,7 +243,11 @@ void init_irq_proc(void)
         /*
          * Create entries for all existing IRQs.
          */
-        for_each_irq_desc(irq, desc)
+        for_each_irq_desc(irq, desc) {
+                if (!desc)
+                        continue;
+
                 register_irq_proc(irq, desc);
+        }
 }
 
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dd364c11e56e..3738107531fd 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -91,6 +91,9 @@ static int misrouted_irq(int irq)
         int i, ok = 0;
 
         for_each_irq_desc(i, desc) {
+                if (!desc)
+                        continue;
+
                 if (!i)
                          continue;
 
@@ -112,6 +115,8 @@ static void poll_spurious_irqs(unsigned long dummy)
         for_each_irq_desc(i, desc) {
                 unsigned int status;
 
+                if (!desc)
+                        continue;
                 if (!i)
                          continue;