6 files changed, 168 insertions, 76 deletions

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 6080f6bc8c33..fc275e4f629b 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -379,8 +379,10 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
          * If its disabled or no action available
          * keep it masked and get out of here
          */
-        if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data)))
+        if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+                desc->istate |= IRQS_PENDING;
                 goto out_unlock;
+        }
 
         handle_irq_event(desc);
 
@@ -518,6 +520,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 out_unlock:
         raw_spin_unlock(&desc->lock);
 }
+EXPORT_SYMBOL(handle_edge_irq);
 
 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
 /**
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index d86e254b95eb..192a302d6cfd 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -112,6 +112,7 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 {
         return radix_tree_lookup(&irq_desc_tree, irq);
 }
+EXPORT_SYMBOL(irq_to_desc);
 
 static void delete_irq_desc(unsigned int irq)
 {
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 0e0ba5f840b2..41c1564103f1 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1,3 +1,5 @@
+#define pr_fmt(fmt)  "irq: " fmt
+
 #include <linux/debugfs.h>
 #include <linux/hardirq.h>
 #include <linux/interrupt.h>
@@ -56,14 +58,73 @@ static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
         return domain;
 }
 
+static void irq_domain_free(struct irq_domain *domain)
+{
+        of_node_put(domain->of_node);
+        kfree(domain);
+}
+
 static void irq_domain_add(struct irq_domain *domain)
 {
         mutex_lock(&irq_domain_mutex);
         list_add(&domain->link, &irq_domain_list);
         mutex_unlock(&irq_domain_mutex);
-        pr_debug("irq: Allocated domain of type %d @0x%p\n",
+        pr_debug("Allocated domain of type %d @0x%p\n",
+                 domain->revmap_type, domain);
+}
+
+/**
+ * irq_domain_remove() - Remove an irq domain.
+ * @domain: domain to remove
+ *
+ * This routine is used to remove an irq domain. The caller must ensure
+ * that all mappings within the domain have been disposed of prior to
+ * use, depending on the revmap type.
+ */
+void irq_domain_remove(struct irq_domain *domain)
+{
+        mutex_lock(&irq_domain_mutex);
+
+        switch (domain->revmap_type) {
+        case IRQ_DOMAIN_MAP_LEGACY:
+                /*
+                 * Legacy domains don't manage their own irq_desc
+                 * allocations, we expect the caller to handle irq_desc
+                 * freeing on their own.
+                 */
+                break;
+        case IRQ_DOMAIN_MAP_TREE:
+                /*
+                 * radix_tree_delete() takes care of destroying the root
+                 * node when all entries are removed. Shout if there are
+                 * any mappings left.
+                 */
+                WARN_ON(domain->revmap_data.tree.height);
+                break;
+        case IRQ_DOMAIN_MAP_LINEAR:
+                kfree(domain->revmap_data.linear.revmap);
+                domain->revmap_data.linear.size = 0;
+                break;
+        case IRQ_DOMAIN_MAP_NOMAP:
+                break;
+        }
+
+        list_del(&domain->link);
+
+        /*
+         * If the going away domain is the default one, reset it.
+         */
+        if (unlikely(irq_default_domain == domain))
+                irq_set_default_host(NULL);
+
+        mutex_unlock(&irq_domain_mutex);
+
+        pr_debug("Removed domain of type %d @0x%p\n",
                  domain->revmap_type, domain);
+
+        irq_domain_free(domain);
 }
+EXPORT_SYMBOL_GPL(irq_domain_remove);
 
 static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
                                              irq_hw_number_t hwirq)
@@ -117,8 +178,7 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 
                 if (WARN_ON(!irq_data || irq_data->domain)) {
                         mutex_unlock(&irq_domain_mutex);
-                        of_node_put(domain->of_node);
-                        kfree(domain);
+                        irq_domain_free(domain);
                         return NULL;
                 }
         }
@@ -152,10 +212,12 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
         irq_domain_add(domain);
         return domain;
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
 
 /**
  * irq_domain_add_linear() - Allocate and register a legacy revmap irq_domain.
  * @of_node: pointer to interrupt controller's device tree node.
+ * @size: Number of interrupts in the domain.
  * @ops: map/unmap domain callbacks
  * @host_data: Controller private data pointer
  */
@@ -181,6 +243,7 @@ struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
         irq_domain_add(domain);
         return domain;
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_linear);
 
 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
                                          unsigned int max_irq,
@@ -195,6 +258,7 @@ struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
         }
         return domain;
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_nomap);
 
 /**
  * irq_domain_add_tree()
@@ -216,6 +280,7 @@ struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
         }
         return domain;
 }
+EXPORT_SYMBOL_GPL(irq_domain_add_tree);
 
 /**
  * irq_find_host() - Locates a domain for a given device node
@@ -259,10 +324,11 @@ EXPORT_SYMBOL_GPL(irq_find_host);
  */
 void irq_set_default_host(struct irq_domain *domain)
 {
-        pr_debug("irq: Default domain set to @0x%p\n", domain);
+        pr_debug("Default domain set to @0x%p\n", domain);
 
         irq_default_domain = domain;
 }
+EXPORT_SYMBOL_GPL(irq_set_default_host);
 
 static int irq_setup_virq(struct irq_domain *domain, unsigned int virq,
                             irq_hw_number_t hwirq)
@@ -272,7 +338,7 @@ static int irq_setup_virq(struct irq_domain *domain, unsigned int virq,
         irq_data->hwirq = hwirq;
         irq_data->domain = domain;
         if (domain->ops->map(domain, virq, hwirq)) {
-                pr_debug("irq: -> mapping failed, freeing\n");
+                pr_debug("irq-%i==>hwirq-0x%lx mapping failed\n", virq, hwirq);
                 irq_data->domain = NULL;
                 irq_data->hwirq = 0;
                 return -1;
@@ -303,7 +369,7 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain)
 
         virq = irq_alloc_desc_from(1, 0);
         if (!virq) {
-                pr_debug("irq: create_direct virq allocation failed\n");
+                pr_debug("create_direct virq allocation failed\n");
                 return 0;
         }
         if (virq >= domain->revmap_data.nomap.max_irq) {
@@ -312,7 +378,7 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain)
                 irq_free_desc(virq);
                 return 0;
         }
-        pr_debug("irq: create_direct obtained virq %d\n", virq);
+        pr_debug("create_direct obtained virq %d\n", virq);
 
         if (irq_setup_virq(domain, virq, virq)) {
                 irq_free_desc(virq);
@@ -321,6 +387,7 @@ unsigned int irq_create_direct_mapping(struct irq_domain *domain)
 
         return virq;
 }
+EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
 
 /**
  * irq_create_mapping() - Map a hardware interrupt into linux irq space
@@ -338,23 +405,23 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
         unsigned int hint;
         int virq;
 
-        pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
+        pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
 
         /* Look for default domain if nececssary */
         if (domain == NULL)
                 domain = irq_default_domain;
         if (domain == NULL) {
-                printk(KERN_WARNING "irq_create_mapping called for"
-                       " NULL domain, hwirq=%lx\n", hwirq);
+                pr_warning("irq_create_mapping called for"
+                           " NULL domain, hwirq=%lx\n", hwirq);
                 WARN_ON(1);
                 return 0;
         }
-        pr_debug("irq: -> using domain @%p\n", domain);
+        pr_debug("-> using domain @%p\n", domain);
 
         /* Check if mapping already exists */
         virq = irq_find_mapping(domain, hwirq);
         if (virq) {
-                pr_debug("irq: -> existing mapping on virq %d\n", virq);
+                pr_debug("-> existing mapping on virq %d\n", virq);
                 return virq;
         }
 
@@ -370,7 +437,7 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
         if (virq <= 0)
                 virq = irq_alloc_desc_from(1, 0);
         if (virq <= 0) {
-                pr_debug("irq: -> virq allocation failed\n");
+                pr_debug("-> virq allocation failed\n");
                 return 0;
         }
 
@@ -380,7 +447,7 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
                 return 0;
         }
 
-        pr_debug("irq: irq %lu on domain %s mapped to virtual irq %u\n",
+        pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
                 hwirq, domain->of_node ? domain->of_node->full_name : "null", virq);
 
         return virq;
@@ -409,8 +476,8 @@ unsigned int irq_create_of_mapping(struct device_node *controller,
                 if (intsize > 0)
                         return intspec[0];
 #endif
-                printk(KERN_WARNING "irq: no irq domain found for %s !\n",
-                       controller->full_name);
+                pr_warning("no irq domain found for %s !\n",
+                           controller->full_name);
                 return 0;
         }
 
@@ -560,6 +627,7 @@ unsigned int irq_radix_revmap_lookup(struct irq_domain *domain,
          */
         return irq_data ? irq_data->irq : irq_find_mapping(domain, hwirq);
 }
+EXPORT_SYMBOL_GPL(irq_radix_revmap_lookup);
 
 /**
  * irq_radix_revmap_insert() - Insert a hw irq to linux irq number mapping.
@@ -584,6 +652,7 @@ void irq_radix_revmap_insert(struct irq_domain *domain, unsigned int virq,
                 mutex_unlock(&revmap_trees_mutex);
         }
 }
+EXPORT_SYMBOL_GPL(irq_radix_revmap_insert);
 
 /**
  * irq_linear_revmap() - Find a linux irq from a hw irq number.
@@ -617,6 +686,7 @@ unsigned int irq_linear_revmap(struct irq_domain *domain,
 
         return revmap[hwirq];
 }
+EXPORT_SYMBOL_GPL(irq_linear_revmap);
 
 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 static int virq_debug_show(struct seq_file *m, void *private)
@@ -691,8 +761,8 @@ static int __init irq_debugfs_init(void)
 __initcall(irq_debugfs_init);
 #endif /* CONFIG_IRQ_DOMAIN_DEBUG */
 
-int irq_domain_simple_map(struct irq_domain *d, unsigned int irq,
-                          irq_hw_number_t hwirq)
+static int irq_domain_simple_map(struct irq_domain *d, unsigned int irq,
+                                 irq_hw_number_t hwirq)
 {
         return 0;
 }
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 89a3ea82569b..ea0c6c2ae6f7 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -7,6 +7,8 @@
  * This file contains driver APIs to the irq subsystem.
  */
 
+#define pr_fmt(fmt) "genirq: " fmt
+
 #include <linux/irq.h>
 #include <linux/kthread.h>
 #include <linux/module.h>
@@ -14,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/task_work.h>
 
 #include "internals.h"
 
@@ -566,7 +569,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                  * flow-types?
                  */
                 pr_debug("No set_type function for IRQ %d (%s)\n", irq,
-                                chip ? (chip->name ? : "unknown") : "unknown");
+                         chip ? (chip->name ? : "unknown") : "unknown");
                 return 0;
         }
 
@@ -600,7 +603,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                 ret = 0;
                 break;
         default:
-                pr_err("setting trigger mode %lu for irq %u failed (%pF)\n",
+                pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
                        flags, irq, chip->irq_set_type);
         }
         if (unmask)
@@ -773,11 +776,39 @@ static void wake_threads_waitq(struct irq_desc *desc)
                 wake_up(&desc->wait_for_threads);
 }
 
+static void irq_thread_dtor(struct task_work *unused)
+{
+        struct task_struct *tsk = current;
+        struct irq_desc *desc;
+        struct irqaction *action;
+
+        if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
+                return;
+
+        action = kthread_data(tsk);
+
+        pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+               tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
+
+
+        desc = irq_to_desc(action->irq);
+        /*
+         * If IRQTF_RUNTHREAD is set, we need to decrement
+         * desc->threads_active and wake possible waiters.
+         */
+        if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+                wake_threads_waitq(desc);
+
+        /* Prevent a stale desc->threads_oneshot */
+        irq_finalize_oneshot(desc, action);
+}
+
 /*
  * Interrupt handler thread
  */
 static int irq_thread(void *data)
 {
+        struct task_work on_exit_work;
         static const struct sched_param param = {
                 .sched_priority = MAX_USER_RT_PRIO/2,
         };
@@ -793,7 +824,9 @@ static int irq_thread(void *data)
                 handler_fn = irq_thread_fn;
 
         sched_setscheduler(current, SCHED_FIFO, &param);
-        current->irq_thread = 1;
+
+        init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+        task_work_add(current, &on_exit_work, false);
 
         while (!irq_wait_for_interrupt(action)) {
                 irqreturn_t action_ret;
@@ -815,45 +848,11 @@ static int irq_thread(void *data)
          * cannot touch the oneshot mask at this point anymore as
          * __setup_irq() might have given out currents thread_mask
          * again.
-         *
-         * Clear irq_thread. Otherwise exit_irq_thread() would make
-         * fuzz about an active irq thread going into nirvana.
          */
-        current->irq_thread = 0;
+        task_work_cancel(current, irq_thread_dtor);
         return 0;
 }
 
-/*
- * Called from do_exit()
- */
-void exit_irq_thread(void)
-{
-        struct task_struct *tsk = current;
-        struct irq_desc *desc;
-        struct irqaction *action;
-
-        if (!tsk->irq_thread)
-                return;
-
-        action = kthread_data(tsk);
-
-        printk(KERN_ERR
-               "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
-               tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
-
-        desc = irq_to_desc(action->irq);
-
-        /*
-         * If IRQTF_RUNTHREAD is set, we need to decrement
-         * desc->threads_active and wake possible waiters.
-         */
-        if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
-                wake_threads_waitq(desc);
-
-        /* Prevent a stale desc->threads_oneshot */
-        irq_finalize_oneshot(desc, action);
-}
-
 static void irq_setup_forced_threading(struct irqaction *new)
 {
         if (!force_irqthreads)
@@ -878,7 +877,6 @@ static int
 __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 {
         struct irqaction *old, **old_ptr;
-        const char *old_name = NULL;
         unsigned long flags, thread_mask = 0;
         int ret, nested, shared = 0;
         cpumask_var_t mask;
@@ -972,10 +970,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                  */
                 if (!((old->flags & new->flags) & IRQF_SHARED) ||
                     ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) ||
-                    ((old->flags ^ new->flags) & IRQF_ONESHOT)) {
-                        old_name = old->name;
+                    ((old->flags ^ new->flags) & IRQF_ONESHOT))
                         goto mismatch;
-                }
 
                 /* All handlers must agree on per-cpuness */
                 if ((old->flags & IRQF_PERCPU) !=
@@ -1031,6 +1027,27 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                  * all existing action->thread_mask bits.
                  */
                 new->thread_mask = 1 << ffz(thread_mask);
+
+        } else if (new->handler == irq_default_primary_handler) {
+                /*
+                 * The interrupt was requested with handler = NULL, so
+                 * we use the default primary handler for it. But it
+                 * does not have the oneshot flag set. In combination
+                 * with level interrupts this is deadly, because the
+                 * default primary handler just wakes the thread, then
+                 * the irq lines is reenabled, but the device still
+                 * has the level irq asserted. Rinse and repeat....
+                 *
+                 * While this works for edge type interrupts, we play
+                 * it safe and reject unconditionally because we can't
+                 * say for sure which type this interrupt really
+                 * has. The type flags are unreliable as the
+                 * underlying chip implementation can override them.
+                 */
+                pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
+                       irq);
+                ret = -EINVAL;
+                goto out_mask;
         }
 
         if (!shared) {
@@ -1078,7 +1095,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 
                 if (nmsk != omsk)
                         /* hope the handler works with current  trigger mode */
-                        pr_warning("IRQ %d uses trigger mode %u; requested %u\n",
+                        pr_warning("irq %d uses trigger mode %u; requested %u\n",
                                    irq, nmsk, omsk);
         }
 
@@ -1115,14 +1132,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
         return 0;
 
 mismatch:
-#ifdef CONFIG_DEBUG_SHIRQ
         if (!(new->flags & IRQF_PROBE_SHARED)) {
-                printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq);
-                if (old_name)
-                        printk(KERN_ERR "current handler: %s\n", old_name);
+                pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
+                       irq, new->flags, new->name, old->flags, old->name);
+#ifdef CONFIG_DEBUG_SHIRQ
                 dump_stack();
-        }
 #endif
+        }
         ret = -EBUSY;
 
 out_mask:
@@ -1204,12 +1220,6 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
         /* 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->irq_data.chip->release)
-                desc->irq_data.chip->release(irq, dev_id);
-#endif
-
         /* If this was the last handler, shut down the IRQ line: */
         if (!desc->action)
                 irq_shutdown(desc);
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
index 15e53b1766a6..cb228bf21760 100644
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -103,8 +103,13 @@ int check_wakeup_irqs(void)
         int irq;
 
         for_each_irq_desc(irq, desc) {
+                /*
+                 * Only interrupts which are marked as wakeup source
+                 * and have not been disabled before the suspend check
+                 * can abort suspend.
+                 */
                 if (irqd_is_wakeup_set(&desc->irq_data)) {
-                        if (desc->istate & IRQS_PENDING)
+                        if (desc->depth == 1 && desc->istate & IRQS_PENDING)
                                 return -EBUSY;
                         continue;
                 }
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 14dd5761e8c9..6454db7b6a4d 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -58,10 +58,13 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
         /*
          * We do not resend level type interrupts. Level type
          * interrupts are resent by hardware when they are still
-         * active.
+         * active. Clear the pending bit so suspend/resume does not
+         * get confused.
          */
-        if (irq_settings_is_level(desc))
+        if (irq_settings_is_level(desc)) {
+                desc->istate &= ~IRQS_PENDING;
                 return;
+        }
         if (desc->istate & IRQS_REPLAY)
                 return;
         if (desc->istate & IRQS_PENDING) {