Merge branch 'irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (32 commits)
  x86: disable __do_IRQ support
  sparseirq, powerpc/cell: fix unused variable warning in interrupt.c
  genirq: deprecate obsolete typedefs and defines
  genirq: deprecate __do_IRQ
  genirq: add doc to struct irqaction
  genirq: use kzalloc instead of explicit zero initialization
  genirq: make irqreturn_t an enum
  genirq: remove redundant if condition
  genirq: remove unused hw_irq_controller typedef
  irq: export remove_irq() and setup_irq() symbols
  irq: match remove_irq() args with setup_irq()
  irq: add remove_irq() for freeing of setup_irq() irqs
  genirq: assert that irq handlers are indeed running in hardirq context
  irq: name 'p' variables a bit better
  irq: further clean up the free_irq() code flow
  irq: refactor and clean up the free_irq() code flow
  irq: clean up manage.c
  irq: use GFP_KERNEL for action allocation in request_irq()
  kernel/irq: fix sparse warning: make symbol static
  irq: optimize init_kstat_irqs/init_copy_kstat_irqs
  ...

37 files changed, 252 insertions, 170 deletions

diff --git a/Documentation/DocBook/genericirq.tmpl b/Documentation/DocBook/genericirq.tmpl
index 3a882d9a90a9..c671a0168096 100644
--- a/Documentation/DocBook/genericirq.tmpl
+++ b/Documentation/DocBook/genericirq.tmpl
@@ -440,6 +440,7 @@ desc->chip->end();
      used in the generic IRQ layer.
      </para>
 !Iinclude/linux/irq.h
+!Iinclude/linux/interrupt.h
   </chapter>
 
   <chapter id="pubfunctions">
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 802c6fd20c63..e47c0ff8ba7a 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -346,3 +346,20 @@ Why:	See commits 129f8ae9b1b5be94517da76009ea956e89104ce8 and
         Removal is subject to fixing any remaining bugs in ACPI which may
         cause the thermal throttling not to happen at the right time.
 Who:    Dave Jones <davej@redhat.com>, Matthew Garrett <mjg@redhat.com>
+
+-----------------------------
+
+What:   __do_IRQ all in one fits nothing interrupt handler
+When:   2.6.32
+Why:    __do_IRQ was kept for easy migration to the type flow handlers.
+        More than two years of migration time is enough.
+Who:    Thomas Gleixner <tglx@linutronix.de>
+
+-----------------------------
+
+What:   obsolete generic irq defines and typedefs
+When:   2.6.30
+Why:    The defines and typedefs (hw_interrupt_type, no_irq_type, irq_desc_t)
+        have been kept around for migration reasons. After more than two years
+        it's time to remove them finally
+Who:    Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
index 703731accda6..d3812eb84015 100644
--- a/arch/alpha/kernel/irq.c
+++ b/arch/alpha/kernel/irq.c
@@ -90,7 +90,7 @@ show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(irq));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[irq]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(irq, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[irq].chip->typename);
                 seq_printf(p, "  %c%s",
diff --git a/arch/alpha/kernel/irq_alpha.c b/arch/alpha/kernel/irq_alpha.c
index e16aeb6e79ef..67c19f8a9944 100644
--- a/arch/alpha/kernel/irq_alpha.c
+++ b/arch/alpha/kernel/irq_alpha.c
@@ -64,7 +64,7 @@ do_entInt(unsigned long type, unsigned long vector,
                 smp_percpu_timer_interrupt(regs);
                 cpu = smp_processor_id();
                 if (cpu != boot_cpuid) {
-                        kstat_cpu(cpu).irqs[RTC_IRQ]++;
+                        kstat_incr_irqs_this_cpu(RTC_IRQ, irq_to_desc(RTC_IRQ));
                 } else {
                         handle_irq(RTC_IRQ);
                 }
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 363db186cb93..7296f0416286 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -76,7 +76,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
                 seq_printf(p, "%3d: ", i);
                 for_each_present_cpu(cpu)
-                        seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, cpu));
                 seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-");
                 seq_printf(p, "  %s", action->name);
                 for (action = action->next; action; action = action->next)
diff --git a/arch/arm/mach-ns9xxx/irq.c b/arch/arm/mach-ns9xxx/irq.c
index 22e0eb6e9ec4..feb0e54a91de 100644
--- a/arch/arm/mach-ns9xxx/irq.c
+++ b/arch/arm/mach-ns9xxx/irq.c
@@ -63,7 +63,6 @@ static struct irq_chip ns9xxx_chip = {
 #else
 static void handle_prio_irq(unsigned int irq, struct irq_desc *desc)
 {
-        unsigned int cpu = smp_processor_id();
         struct irqaction *action;
         irqreturn_t action_ret;
 
@@ -72,7 +71,7 @@ static void handle_prio_irq(unsigned int irq, struct irq_desc *desc)
         BUG_ON(desc->status & IRQ_INPROGRESS);
 
         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
-        kstat_cpu(cpu).irqs[irq]++;
+        kstat_incr_irqs_this_cpu(irq, desc);
 
         action = desc->action;
         if (unlikely(!action || (desc->status & IRQ_DISABLED)))
diff --git a/arch/avr32/kernel/irq.c b/arch/avr32/kernel/irq.c
index a8e767d836aa..9f572229d318 100644
--- a/arch/avr32/kernel/irq.c
+++ b/arch/avr32/kernel/irq.c
@@ -58,7 +58,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
                 seq_printf(p, "%3d: ", i);
                 for_each_online_cpu(cpu)
-                        seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, cpu));
                 seq_printf(p, " %8s", irq_desc[i].chip->name ? : "-");
                 seq_printf(p, "  %s", action->name);
                 for (action = action->next; action; action = action->next)
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c
index 7fd126564846..bd052a67032e 100644
--- a/arch/blackfin/kernel/irqchip.c
+++ b/arch/blackfin/kernel/irqchip.c
@@ -83,7 +83,7 @@ int show_interrupts(struct seq_file *p, void *v)
                         goto skip;
                 seq_printf(p, "%3d: ", i);
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
                 seq_printf(p, " %8s", irq_desc[i].chip->name);
                 seq_printf(p, "  %s", action->name);
                 for (action = action->next; action; action = action->next)
diff --git a/arch/cris/kernel/irq.c b/arch/cris/kernel/irq.c
index 2dfac8c79090..7f642fcffbfc 100644
--- a/arch/cris/kernel/irq.c
+++ b/arch/cris/kernel/irq.c
@@ -66,7 +66,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/frv/kernel/irq.c b/arch/frv/kernel/irq.c
index 73abae767fdc..af3e824b91b3 100644
--- a/arch/frv/kernel/irq.c
+++ b/arch/frv/kernel/irq.c
@@ -74,7 +74,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 if (action) {
                         seq_printf(p, "%3d: ", i);
                         for_each_present_cpu(cpu)
-                                seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
+                                seq_printf(p, "%10u ", kstat_irqs_cpu(i, cpu));
                         seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-");
                         seq_printf(p, "  %s", action->name);
                         for (action = action->next;
diff --git a/arch/h8300/kernel/irq.c b/arch/h8300/kernel/irq.c
index ef4f0047067d..74f8dd7b34d2 100644
--- a/arch/h8300/kernel/irq.c
+++ b/arch/h8300/kernel/irq.c
@@ -183,7 +183,7 @@ asmlinkage void do_IRQ(int irq)
 #if defined(CONFIG_PROC_FS)
 int show_interrupts(struct seq_file *p, void *v)
 {
-        int i = *(loff_t *) v, j;
+        int i = *(loff_t *) v;
         struct irqaction * action;
         unsigned long flags;
 
@@ -196,7 +196,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 if (!action)
                         goto unlock;
                 seq_printf(p, "%3d: ",i);
-                seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                seq_printf(p, "%10u ", kstat_irqs(i));
                 seq_printf(p, " %14s", irq_desc[i].chip->name);
                 seq_printf(p, "-%-8s", irq_desc[i].name);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
index a58f64ca9f0e..4f596613bffd 100644
--- a/arch/ia64/kernel/irq.c
+++ b/arch/ia64/kernel/irq.c
@@ -80,7 +80,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j) {
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
                 }
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->name);
diff --git a/arch/m32r/kernel/irq.c b/arch/m32r/kernel/irq.c
index 2aeae4670098..8dfd31e87c4c 100644
--- a/arch/m32r/kernel/irq.c
+++ b/arch/m32r/kernel/irq.c
@@ -49,7 +49,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index 4b4007b3083a..7b845ba9dff4 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -108,7 +108,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->name);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/mn10300/kernel/irq.c b/arch/mn10300/kernel/irq.c
index 56c64ccc9c21..50fdb5c16e0c 100644
--- a/arch/mn10300/kernel/irq.c
+++ b/arch/mn10300/kernel/irq.c
@@ -221,7 +221,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 if (action) {
                         seq_printf(p, "%3d: ", i);
                         for_each_present_cpu(cpu)
-                                seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
+                                seq_printf(p, "%10u ", kstat_irqs_cpu(i, cpu));
                         seq_printf(p, " %14s.%u", irq_desc[i].chip->name,
                                    (GxICR(i) & GxICR_LEVEL) >>
                                    GxICR_LEVEL_SHIFT);
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index 29e70e16ede8..adfd617b4c18 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -185,7 +185,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%3d: ", i);
 #ifdef CONFIG_SMP
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #else
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #endif
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 23b8b5e36f98..17efb7118db1 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -190,7 +190,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%3d: ", i);
 #ifdef CONFIG_SMP
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #else
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #endif /* CONFIG_SMP */
diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c
index 28c04dab2633..882e47080e74 100644
--- a/arch/powerpc/platforms/cell/interrupt.c
+++ b/arch/powerpc/platforms/cell/interrupt.c
@@ -237,8 +237,6 @@ extern int noirqdebug;
 
 static void handle_iic_irq(unsigned int irq, struct irq_desc *desc)
 {
-        const unsigned int cpu = smp_processor_id();
-
         spin_lock(&desc->lock);
 
         desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
@@ -254,7 +252,7 @@ static void handle_iic_irq(unsigned int irq, struct irq_desc *desc)
                 goto out_eoi;
         }
 
-        kstat_cpu(cpu).irqs[irq]++;
+        kstat_incr_irqs_this_cpu(irq, desc);
 
         /* Mark the IRQ currently in progress.*/
         desc->status |= IRQ_INPROGRESS;
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index 90d63aefd275..3f1372eb0091 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -51,7 +51,7 @@ int show_interrupts(struct seq_file *p, void *v)
                         goto unlock;
                 seq_printf(p, "%3d: ",i);
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
                 seq_printf(p, " %14s", irq_desc[i].chip->name);
                 seq_printf(p, "-%-8s", irq_desc[i].name);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/sparc/kernel/irq_64.c b/arch/sparc/kernel/irq_64.c
index 1c378d8e90c5..8ba064f08a6f 100644
--- a/arch/sparc/kernel/irq_64.c
+++ b/arch/sparc/kernel/irq_64.c
@@ -185,7 +185,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %9s", irq_desc[i].chip->typename);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c
index 2db3c2229b95..642562d83ec4 100644
--- a/arch/sparc/kernel/time_64.c
+++ b/arch/sparc/kernel/time_64.c
@@ -36,10 +36,10 @@
 #include <linux/clocksource.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
+#include <linux/irq.h>
 
 #include <asm/oplib.h>
 #include <asm/timer.h>
-#include <asm/irq.h>
 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/starfire.h>
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 3d7aad09b171..336b61569072 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -42,7 +42,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
                 seq_printf(p, "  %s", action->name);
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index bc2fbadff9f9..3a330a437c6f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -165,6 +165,9 @@ config GENERIC_HARDIRQS
         bool
         default y
 
+config GENERIC_HARDIRQS_NO__DO_IRQ
+       def_bool y
+
 config GENERIC_IRQ_PROBE
         bool
         default y
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
index 5fbcde59a92d..f3b66fba5b8f 100644
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -99,7 +99,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
                 for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
                 seq_printf(p, "  %s", action->name);
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 7c13581ca9cd..7c43ae782b26 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -241,6 +241,10 @@
 #include <linux/percpu.h>
 #include <linux/cryptohash.h>
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+# include <linux/irq.h>
+#endif
+
 #include <asm/processor.h>
 #include <asm/uaccess.h>
 #include <asm/irq.h>
@@ -558,7 +562,7 @@ struct timer_rand_state {
         unsigned dont_count_entropy:1;
 };
 
-#ifndef CONFIG_SPARSE_IRQ
+#ifndef CONFIG_GENERIC_HARDIRQS
 
 static struct timer_rand_state *irq_timer_state[NR_IRQS];
 
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index 45effc5726c0..b721c2fbe8f5 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -20,7 +20,7 @@ struct irq_2_iommu {
         u8  irte_mask;
 };
 
-#ifdef CONFIG_SPARSE_IRQ
+#ifdef CONFIG_GENERIC_HARDIRQS
 static struct irq_2_iommu *get_one_free_irq_2_iommu(int cpu)
 {
         struct irq_2_iommu *iommu;
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 9127f6b51a39..91658d076598 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -61,6 +61,17 @@
 
 typedef irqreturn_t (*irq_handler_t)(int, void *);
 
+/**
+ * struct irqaction - per interrupt action descriptor
+ * @handler:    interrupt handler function
+ * @flags:      flags (see IRQF_* above)
+ * @mask:       no comment as it is useless and about to be removed
+ * @name:       name of the device
+ * @dev_id:     cookie to identify the device
+ * @next:       pointer to the next irqaction for shared interrupts
+ * @irq:        interrupt number
+ * @dir:        pointer to the proc/irq/NN/name entry
+ */
 struct irqaction {
         irq_handler_t handler;
         unsigned long flags;
@@ -462,6 +473,12 @@ static inline void init_irq_proc(void)
 }
 #endif
 
+#if defined(CONFIG_GENERIC_HARDIRQS) && defined(CONFIG_DEBUG_SHIRQ)
+extern void debug_poll_all_shared_irqs(void);
+#else
+static inline void debug_poll_all_shared_irqs(void) { }
+#endif
+
 int show_interrupts(struct seq_file *p, void *v);
 
 struct irq_desc;
diff --git a/include/linux/irq.h b/include/linux/irq.h
index f899b502f186..6db939a575bd 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -160,12 +160,10 @@ struct irq_2_iommu;
  */
 struct irq_desc {
         unsigned int            irq;
-#ifdef CONFIG_SPARSE_IRQ
         struct timer_rand_state *timer_rand_state;
         unsigned int            *kstat_irqs;
-# ifdef CONFIG_INTR_REMAP
+#ifdef CONFIG_INTR_REMAP
         struct irq_2_iommu      *irq_2_iommu;
-# endif
 #endif
         irq_flow_handler_t      handle_irq;
         struct irq_chip         *chip;
@@ -202,12 +200,6 @@ extern void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc
 extern struct irq_desc irq_desc[NR_IRQS];
 #else /* CONFIG_SPARSE_IRQ */
 extern struct irq_desc *move_irq_desc(struct irq_desc *old_desc, int cpu);
-
-#define kstat_irqs_this_cpu(DESC) \
-        ((DESC)->kstat_irqs[smp_processor_id()])
-#define kstat_incr_irqs_this_cpu(irqno, DESC) \
-        ((DESC)->kstat_irqs[smp_processor_id()]++)
-
 #endif /* CONFIG_SPARSE_IRQ */
 
 extern struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu);
@@ -226,7 +218,6 @@ irq_remap_to_desc(unsigned int irq, struct irq_desc *desc)
  * Migration helpers for obsolete names, they will go away:
  */
 #define hw_interrupt_type       irq_chip
-typedef struct irq_chip         hw_irq_controller;
 #define no_irq_type             no_irq_chip
 typedef struct irq_desc         irq_desc_t;
 
@@ -236,6 +227,7 @@ typedef struct irq_desc		irq_desc_t;
 #include <asm/hw_irq.h>
 
 extern int setup_irq(unsigned int irq, struct irqaction *new);
+extern void remove_irq(unsigned int irq, struct irqaction *act);
 
 #ifdef CONFIG_GENERIC_HARDIRQS
 
@@ -280,7 +272,7 @@ static inline int irq_balancing_disabled(unsigned int irq)
 }
 
 /* Handle irq action chains: */
-extern int handle_IRQ_event(unsigned int irq, struct irqaction *action);
+extern irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action);
 
 /*
  * Built-in IRQ handlers for various IRQ types,
@@ -325,7 +317,7 @@ static inline void generic_handle_irq(unsigned int irq)
 
 /* Handling of unhandled and spurious interrupts: */
 extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
-                           int action_ret);
+                           irqreturn_t action_ret);
 
 /* Resending of interrupts :*/
 void check_irq_resend(struct irq_desc *desc, unsigned int irq);
diff --git a/include/linux/irqnr.h b/include/linux/irqnr.h
index 86af92e9e84c..52ebbb4b161d 100644
--- a/include/linux/irqnr.h
+++ b/include/linux/irqnr.h
@@ -28,13 +28,17 @@ extern struct irq_desc *irq_to_desc(unsigned int irq);
 # define for_each_irq_desc(irq, desc)                                   \
         for (irq = 0, desc = irq_to_desc(irq); irq < nr_irqs;           \
              irq++, desc = irq_to_desc(irq))                            \
-                if (desc)
+                if (!desc)                                              \
+                        ;                                               \
+                else
 
 
 # define for_each_irq_desc_reverse(irq, desc)                           \
         for (irq = nr_irqs - 1, desc = irq_to_desc(irq); irq >= 0;      \
              irq--, desc = irq_to_desc(irq))                            \
-                if (desc)
+                if (!desc)                                              \
+                        ;                                               \
+                else
 
 #endif /* CONFIG_GENERIC_HARDIRQS */
 
diff --git a/include/linux/irqreturn.h b/include/linux/irqreturn.h
index 881883c2009d..c5584ca5b8c9 100644
--- a/include/linux/irqreturn.h
+++ b/include/linux/irqreturn.h
@@ -1,25 +1,17 @@
-/* irqreturn.h */
 #ifndef _LINUX_IRQRETURN_H
 #define _LINUX_IRQRETURN_H
 
-/*
- * For 2.4.x compatibility, 2.4.x can use
- *
- *      typedef void irqreturn_t;
- *      #define IRQ_NONE
- *      #define IRQ_HANDLED
- *      #define IRQ_RETVAL(x)
- *
- * To mix old-style and new-style irq handler returns.
- *
- * IRQ_NONE means we didn't handle it.
- * IRQ_HANDLED means that we did have a valid interrupt and handled it.
- * IRQ_RETVAL(x) selects on the two depending on x being non-zero (for handled)
+/**
+ * enum irqreturn
+ * @IRQ_NONE            interrupt was not from this device
+ * @IRQ_HANDLED         interrupt was handled by this device
  */
-typedef int irqreturn_t;
+enum irqreturn {
+        IRQ_NONE,
+        IRQ_HANDLED,
+};
 
-#define IRQ_NONE        (0)
-#define IRQ_HANDLED     (1)
-#define IRQ_RETVAL(x)   ((x) != 0)
+typedef enum irqreturn irqreturn_t;
+#define IRQ_RETVAL(x)   ((x) != IRQ_NONE)
 
 #endif
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index 570d20413119..0c8b89f28a95 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -28,7 +28,7 @@ struct cpu_usage_stat {
 
 struct kernel_stat {
         struct cpu_usage_stat   cpustat;
-#ifndef CONFIG_SPARSE_IRQ
+#ifndef CONFIG_GENERIC_HARDIRQS
        unsigned int irqs[NR_IRQS];
 #endif
 };
@@ -41,7 +41,7 @@ DECLARE_PER_CPU(struct kernel_stat, kstat);
 
 extern unsigned long long nr_context_switches(void);
 
-#ifndef CONFIG_SPARSE_IRQ
+#ifndef CONFIG_GENERIC_HARDIRQS
 #define kstat_irqs_this_cpu(irq) \
         (kstat_this_cpu.irqs[irq])
 
@@ -52,16 +52,19 @@ static inline void kstat_incr_irqs_this_cpu(unsigned int irq,
 {
         kstat_this_cpu.irqs[irq]++;
 }
-#endif
-
 
-#ifndef CONFIG_SPARSE_IRQ
 static inline unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 {
        return kstat_cpu(cpu).irqs[irq];
 }
 #else
+#include <linux/irq.h>
 extern unsigned int kstat_irqs_cpu(unsigned int irq, int cpu);
+#define kstat_irqs_this_cpu(DESC) \
+        ((DESC)->kstat_irqs[smp_processor_id()])
+#define kstat_incr_irqs_this_cpu(irqno, DESC) \
+        ((DESC)->kstat_irqs[smp_processor_id()]++)
+
 #endif
 
 /*
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 7de11bd64dfe..03d0bed2b8d9 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -78,6 +78,7 @@ void dynamic_irq_cleanup(unsigned int irq)
         desc->handle_irq = handle_bad_irq;
         desc->chip = &no_irq_chip;
         desc->name = NULL;
+        clear_kstat_irqs(desc);
         spin_unlock_irqrestore(&desc->lock, flags);
 }
 
@@ -290,7 +291,8 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
                 desc->chip->mask_ack(irq);
         else {
                 desc->chip->mask(irq);
-                desc->chip->ack(irq);
+                if (desc->chip->ack)
+                        desc->chip->ack(irq);
         }
 }
 
@@ -476,7 +478,8 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
         kstat_incr_irqs_this_cpu(irq, desc);
 
         /* Start handling the irq */
-        desc->chip->ack(irq);
+        if (desc->chip->ack)
+                desc->chip->ack(irq);
         desc = irq_remap_to_desc(irq, desc);
 
         /* Mark the IRQ currently in progress.*/
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 3aba8d12f328..f6cdda68e5c6 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -83,19 +83,21 @@ static struct irq_desc irq_desc_init = {
 
 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);
+        void *ptr;
 
         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);
+        ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), GFP_ATOMIC, node);
 
-        if (ptr)
-                desc->kstat_irqs = (unsigned int *)ptr;
+        /*
+         * don't overwite if can not get new one
+         * init_copy_kstat_irqs() could still use old one
+         */
+        if (ptr) {
+                printk(KERN_DEBUG "  alloc kstat_irqs on cpu %d node %d\n",
+                         cpu, node);
+                desc->kstat_irqs = ptr;
+        }
 }
 
 static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
@@ -227,6 +229,7 @@ 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)
 {
         struct irq_desc *desc;
@@ -238,8 +241,10 @@ int __init early_irq_init(void)
         desc = irq_desc;
         count = ARRAY_SIZE(irq_desc);
 
-        for (i = 0; i < count; i++)
+        for (i = 0; i < count; i++) {
                 desc[i].irq = i;
+                desc[i].kstat_irqs = kstat_irqs_all[i];
+        }
 
         return arch_early_irq_init();
 }
@@ -255,6 +260,11 @@ struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
 }
 #endif /* !CONFIG_SPARSE_IRQ */
 
+void clear_kstat_irqs(struct irq_desc *desc)
+{
+        memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
+}
+
 /*
  * What should we do if we get a hw irq event on an illegal vector?
  * Each architecture has to answer this themself.
@@ -328,6 +338,8 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
         irqreturn_t ret, retval = IRQ_NONE;
         unsigned int status = 0;
 
+        WARN_ONCE(!in_irq(), "BUG: IRQ handler called from non-hardirq context!");
+
         if (!(action->flags & IRQF_DISABLED))
                 local_irq_enable_in_hardirq();
 
@@ -347,6 +359,11 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
 }
 
 #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
@@ -467,12 +484,10 @@ void early_init_irq_lock_class(void)
         }
 }
 
-#ifdef CONFIG_SPARSE_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;
 }
-#endif
 EXPORT_SYMBOL(kstat_irqs_cpu);
 
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index e6d0a43cc125..b60950bf5a16 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -15,6 +15,7 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
 
 extern struct lock_class_key irq_desc_lock_class;
 extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
+extern void clear_kstat_irqs(struct irq_desc *desc);
 extern spinlock_t sparse_irq_lock;
 extern struct irq_desc *irq_desc_ptrs[NR_IRQS];
 
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 291f03664552..ea119effe096 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -109,7 +109,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
 /*
  * Generic version of the affinity autoselector.
  */
-int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
+static int setup_affinity(unsigned int irq, struct irq_desc *desc)
 {
         if (!irq_can_set_affinity(irq))
                 return 0;
@@ -133,7 +133,7 @@ set_affinity:
         return 0;
 }
 #else
-static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
 {
         return irq_select_affinity(irq);
 }
@@ -149,14 +149,14 @@ int irq_select_affinity_usr(unsigned int irq)
         int ret;
 
         spin_lock_irqsave(&desc->lock, flags);
-        ret = do_irq_select_affinity(irq, desc);
+        ret = setup_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)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
 {
         return 0;
 }
@@ -389,9 +389,9 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
  * allocate special interrupts that are part of the architecture.
  */
 static int
-__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
+__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 {
-        struct irqaction *old, **p;
+        struct irqaction *old, **old_ptr;
         const char *old_name = NULL;
         unsigned long flags;
         int shared = 0;
@@ -423,8 +423,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
          * The following block of code has to be executed atomically
          */
         spin_lock_irqsave(&desc->lock, flags);
-        p = &desc->action;
-        old = *p;
+        old_ptr = &desc->action;
+        old = *old_ptr;
         if (old) {
                 /*
                  * Can't share interrupts unless both agree to and are
@@ -447,8 +447,8 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
 
                 /* add new interrupt at end of irq queue */
                 do {
-                        p = &old->next;
-                        old = *p;
+                        old_ptr = &old->next;
+                        old = *old_ptr;
                 } while (old);
                 shared = 1;
         }
@@ -488,7 +488,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
                         desc->status |= IRQ_NO_BALANCING;
 
                 /* Set default affinity mask once everything is setup */
-                do_irq_select_affinity(irq, desc);
+                setup_affinity(irq, desc);
 
         } else if ((new->flags & IRQF_TRIGGER_MASK)
                         && (new->flags & IRQF_TRIGGER_MASK)
@@ -499,7 +499,7 @@ __setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
                                 (int)(new->flags & IRQF_TRIGGER_MASK));
         }
 
-        *p = new;
+        *old_ptr = new;
 
         /* Reset broken irq detection when installing new handler */
         desc->irq_count = 0;
@@ -549,90 +549,117 @@ int setup_irq(unsigned int irq, struct irqaction *act)
 
         return __setup_irq(irq, desc, act);
 }
+EXPORT_SYMBOL_GPL(setup_irq);
 
-/**
- *      free_irq - free an interrupt
- *      @irq: Interrupt line to free
- *      @dev_id: Device identity to free
- *
- *      Remove an interrupt handler. The handler is removed and if the
- *      interrupt line is no longer in use by any driver it is disabled.
- *      On a shared IRQ the caller must ensure the interrupt is disabled
- *      on the card it drives before calling this function. The function
- *      does not return until any executing interrupts for this IRQ
- *      have completed.
- *
- *      This function must not be called from interrupt context.
+ /*
+ * Internal function to unregister an irqaction - used to free
+ * regular and special interrupts that are part of the architecture.
  */
-void free_irq(unsigned int irq, void *dev_id)
+static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 {
         struct irq_desc *desc = irq_to_desc(irq);
-        struct irqaction **p;
+        struct irqaction *action, **action_ptr;
         unsigned long flags;
 
-        WARN_ON(in_interrupt());
+        WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
 
         if (!desc)
-                return;
+                return NULL;
 
         spin_lock_irqsave(&desc->lock, flags);
-        p = &desc->action;
+
+        /*
+         * There can be multiple actions per IRQ descriptor, find the right
+         * one based on the dev_id:
+         */
+        action_ptr = &desc->action;
         for (;;) {
-                struct irqaction *action = *p;
+                action = *action_ptr;
 
-                if (action) {
-                        struct irqaction **pp = p;
+                if (!action) {
+                        WARN(1, "Trying to free already-free IRQ %d\n", irq);
+                        spin_unlock_irqrestore(&desc->lock, flags);
 
-                        p = &action->next;
-                        if (action->dev_id != dev_id)
-                                continue;
+                        return NULL;
+                }
 
-                        /* Found it - now remove it from the list of entries */
-                        *pp = action->next;
+                if (action->dev_id == dev_id)
+                        break;
+                action_ptr = &action->next;
+        }
 
-                        /* Currently used only by UML, might disappear one day.*/
+        /* Found it - now remove it from the list of entries: */
+        *action_ptr = action->next;
+
+        /* Currently used only by UML, might disappear one day: */
 #ifdef CONFIG_IRQ_RELEASE_METHOD
-                        if (desc->chip->release)
-                                desc->chip->release(irq, dev_id);
+        if (desc->chip->release)
+                desc->chip->release(irq, dev_id);
 #endif
 
-                        if (!desc->action) {
-                                desc->status |= IRQ_DISABLED;
-                                if (desc->chip->shutdown)
-                                        desc->chip->shutdown(irq);
-                                else
-                                        desc->chip->disable(irq);
-                        }
-                        spin_unlock_irqrestore(&desc->lock, flags);
-                        unregister_handler_proc(irq, action);
+        /* If this was the last handler, shut down the IRQ line: */
+        if (!desc->action) {
+                desc->status |= IRQ_DISABLED;
+                if (desc->chip->shutdown)
+                        desc->chip->shutdown(irq);
+                else
+                        desc->chip->disable(irq);
+        }
+        spin_unlock_irqrestore(&desc->lock, flags);
+
+        unregister_handler_proc(irq, action);
+
+        /* Make sure it's not being used on another CPU: */
+        synchronize_irq(irq);
 
-                        /* Make sure it's not being used on another CPU */
-                        synchronize_irq(irq);
-#ifdef CONFIG_DEBUG_SHIRQ
-                        /*
-                         * It's a shared IRQ -- the driver ought to be
-                         * prepared for it to happen even now it's
-                         * being freed, so let's make sure....  We do
-                         * this after actually deregistering it, to
-                         * make sure that a 'real' IRQ doesn't run in
-                         * parallel with our fake
-                         */
-                        if (action->flags & IRQF_SHARED) {
-                                local_irq_save(flags);
-                                action->handler(irq, dev_id);
-                                local_irq_restore(flags);
-                        }
-#endif
-                        kfree(action);
-                        return;
-                }
-                printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
 #ifdef CONFIG_DEBUG_SHIRQ
-                dump_stack();
-#endif
-                spin_unlock_irqrestore(&desc->lock, flags);
-                return;
+        /*
+         * It's a shared IRQ -- the driver ought to be prepared for an IRQ
+         * event to happen even now it's being freed, so let's make sure that
+         * is so by doing an extra call to the handler ....
+         *
+         * ( We do this after actually deregistering it, to make sure that a
+         *   'real' IRQ doesn't run in * parallel with our fake. )
+         */
+        if (action->flags & IRQF_SHARED) {
+                local_irq_save(flags);
+                action->handler(irq, dev_id);
+                local_irq_restore(flags);
         }
+#endif
+        return action;
+}
+
+/**
+ *      remove_irq - free an interrupt
+ *      @irq: Interrupt line to free
+ *      @act: irqaction for the interrupt
+ *
+ * Used to remove interrupts statically setup by the early boot process.
+ */
+void remove_irq(unsigned int irq, struct irqaction *act)
+{
+        __free_irq(irq, act->dev_id);
+}
+EXPORT_SYMBOL_GPL(remove_irq);
+
+/**
+ *      free_irq - free an interrupt allocated with request_irq
+ *      @irq: Interrupt line to free
+ *      @dev_id: Device identity to free
+ *
+ *      Remove an interrupt handler. The handler is removed and if the
+ *      interrupt line is no longer in use by any driver it is disabled.
+ *      On a shared IRQ the caller must ensure the interrupt is disabled
+ *      on the card it drives before calling this function. The function
+ *      does not return until any executing interrupts for this IRQ
+ *      have completed.
+ *
+ *      This function must not be called from interrupt context.
+ */
+void free_irq(unsigned int irq, void *dev_id)
+{
+        kfree(__free_irq(irq, dev_id));
 }
 EXPORT_SYMBOL(free_irq);
 
@@ -679,11 +706,12 @@ int request_irq(unsigned int irq, irq_handler_t handler,
          * the behavior is classified as "will not fix" so we need to
          * start nudging drivers away from using that idiom.
          */
-        if ((irqflags & (IRQF_SHARED|IRQF_DISABLED))
-                        == (IRQF_SHARED|IRQF_DISABLED))
-                pr_warning("IRQ %d/%s: IRQF_DISABLED is not "
-                                "guaranteed on shared IRQs\n",
-                                irq, devname);
+        if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
+                                        (IRQF_SHARED|IRQF_DISABLED)) {
+                pr_warning(
+                  "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
+                        irq, devname);
+        }
 
 #ifdef CONFIG_LOCKDEP
         /*
@@ -709,15 +737,13 @@ int request_irq(unsigned int irq, irq_handler_t handler,
         if (!handler)
                 return -EINVAL;
 
-        action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+        action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
         if (!action)
                 return -ENOMEM;
 
         action->handler = handler;
         action->flags = irqflags;
-        cpus_clear(action->mask);
         action->name = devname;
-        action->next = NULL;
         action->dev_id = dev_id;
 
         retval = __setup_irq(irq, desc, action);
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
index acd88356ac76..aef18ab6b75b 100644
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -17,16 +17,11 @@ 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);
-        }
+        if (desc->kstat_irqs != old_desc->kstat_irqs)
+                memcpy(desc->kstat_irqs, old_desc->kstat_irqs,
+                         nr * sizeof(*desc->kstat_irqs));
 }
 
 static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index dd364c11e56e..4d568294de3e 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -104,7 +104,7 @@ static int misrouted_irq(int irq)
         return ok;
 }
 
-static void poll_spurious_irqs(unsigned long dummy)
+static void poll_all_shared_irqs(void)
 {
         struct irq_desc *desc;
         int i;
@@ -123,11 +123,23 @@ static void poll_spurious_irqs(unsigned long dummy)
 
                 try_one_irq(i, desc);
         }
+}
+
+static void poll_spurious_irqs(unsigned long dummy)
+{
+        poll_all_shared_irqs();
 
         mod_timer(&poll_spurious_irq_timer,
                   jiffies + POLL_SPURIOUS_IRQ_INTERVAL);
 }
 
+#ifdef CONFIG_DEBUG_SHIRQ
+void debug_poll_all_shared_irqs(void)
+{
+        poll_all_shared_irqs();
+}
+#endif
+
 /*
  * If 99,900 of the previous 100,000 interrupts have not been handled
  * then assume that the IRQ is stuck in some manner. Drop a diagnostic