1 files changed, 283 insertions, 100 deletions

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 7eee98c38f25..40fe7806cc8c 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -25,12 +25,11 @@
 #include "internals.h"
 
 #if defined(CONFIG_IRQ_FORCED_THREADING) && !defined(CONFIG_PREEMPT_RT)
-__read_mostly bool force_irqthreads;
-EXPORT_SYMBOL_GPL(force_irqthreads);
+DEFINE_STATIC_KEY_FALSE(force_irqthreads_key);
 
 static int __init setup_forced_irqthreads(char *arg)
 {
-	force_irqthreads = true;
+	static_branch_enable(&force_irqthreads_key);
 	return 0;
 }
 early_param("threadirqs", setup_forced_irqthreads);
@@ -179,7 +178,7 @@ bool irq_can_set_affinity_usr(unsigned int irq)
 
 /**
  *	irq_set_thread_affinity - Notify irq threads to adjust affinity
- *	@desc:		irq descriptor which has affitnity changed
+ *	@desc:		irq descriptor which has affinity changed
  *
  *	We just set IRQTF_AFFINITY and delegate the affinity setting
  *	to the interrupt thread itself. We can not call
@@ -195,9 +194,9 @@ void irq_set_thread_affinity(struct irq_desc *desc)
 			set_bit(IRQTF_AFFINITY, &action->thread_flags);
 }
 
+#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 static void irq_validate_effective_affinity(struct irq_data *data)
 {
-#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 	const struct cpumask *m = irq_data_get_effective_affinity_mask(data);
 	struct irq_chip *chip = irq_data_get_irq_chip(data);
 
@@ -205,19 +204,26 @@ static void irq_validate_effective_affinity(struct irq_data *data)
 		return;
 	pr_warn_once("irq_chip %s did not update eff. affinity mask of irq %u\n",
 		     chip->name, data->irq);
-#endif
 }
+#else
+static inline void irq_validate_effective_affinity(struct irq_data *data) { }
+#endif
 
 int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 			bool force)
 {
 	struct irq_desc *desc = irq_data_to_desc(data);
 	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	const struct cpumask  *prog_mask;
 	int ret;
 
+	static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
+	static struct cpumask tmp_mask;
+
 	if (!chip || !chip->irq_set_affinity)
 		return -EINVAL;
 
+	raw_spin_lock(&tmp_mask_lock);
 	/*
 	 * If this is a managed interrupt and housekeeping is enabled on
 	 * it check whether the requested affinity mask intersects with
@@ -238,30 +244,40 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	 * online.
 	 */
 	if (irqd_affinity_is_managed(data) &&
-	    housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
-		const struct cpumask *hk_mask, *prog_mask;
-
-		static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
-		static struct cpumask tmp_mask;
+	    housekeeping_enabled(HK_TYPE_MANAGED_IRQ)) {
+		const struct cpumask *hk_mask;
 
-		hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+		hk_mask = housekeeping_cpumask(HK_TYPE_MANAGED_IRQ);
 
-		raw_spin_lock(&tmp_mask_lock);
 		cpumask_and(&tmp_mask, mask, hk_mask);
 		if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
 			prog_mask = mask;
 		else
 			prog_mask = &tmp_mask;
-		ret = chip->irq_set_affinity(data, prog_mask, force);
-		raw_spin_unlock(&tmp_mask_lock);
 	} else {
-		ret = chip->irq_set_affinity(data, mask, force);
+		prog_mask = mask;
 	}
+
+	/*
+	 * Make sure we only provide online CPUs to the irqchip,
+	 * unless we are being asked to force the affinity (in which
+	 * case we do as we are told).
+	 */
+	cpumask_and(&tmp_mask, prog_mask, cpu_online_mask);
+	if (!force && !cpumask_empty(&tmp_mask))
+		ret = chip->irq_set_affinity(data, &tmp_mask, force);
+	else if (force)
+		ret = chip->irq_set_affinity(data, mask, force);
+	else
+		ret = -EINVAL;
+
+	raw_spin_unlock(&tmp_mask_lock);
+
 	switch (ret) {
 	case IRQ_SET_MASK_OK:
 	case IRQ_SET_MASK_OK_DONE:
 		cpumask_copy(desc->irq_common_data.affinity, mask);
-		/* fall through */
+		fallthrough;
 	case IRQ_SET_MASK_OK_NOCOPY:
 		irq_validate_effective_affinity(data);
 		irq_set_thread_affinity(desc);
@@ -304,6 +320,30 @@ static int irq_try_set_affinity(struct irq_data *data,
 	return ret;
 }
 
+static bool irq_set_affinity_deactivated(struct irq_data *data,
+					 const struct cpumask *mask, bool force)
+{
+	struct irq_desc *desc = irq_data_to_desc(data);
+
+	/*
+	 * Handle irq chips which can handle affinity only in activated
+	 * state correctly
+	 *
+	 * If the interrupt is not yet activated, just store the affinity
+	 * mask and do not call the chip driver at all. On activation the
+	 * driver has to make sure anyway that the interrupt is in a
+	 * usable state so startup works.
+	 */
+	if (!IS_ENABLED(CONFIG_IRQ_DOMAIN_HIERARCHY) ||
+	    irqd_is_activated(data) || !irqd_affinity_on_activate(data))
+		return false;
+
+	cpumask_copy(desc->irq_common_data.affinity, mask);
+	irq_data_update_effective_affinity(data, mask);
+	irqd_set(data, IRQD_AFFINITY_SET);
+	return true;
+}
+
 int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 			    bool force)
 {
@@ -314,6 +354,9 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 	if (!chip || !chip->irq_set_affinity)
 		return -EINVAL;
 
+	if (irq_set_affinity_deactivated(data, mask, force))
+		return 0;
+
 	if (irq_can_move_pcntxt(data) && !irqd_is_setaffinity_pending(data)) {
 		ret = irq_try_set_affinity(data, mask, force);
 	} else {
@@ -323,14 +366,89 @@ int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
 
 	if (desc->affinity_notify) {
 		kref_get(&desc->affinity_notify->kref);
-		schedule_work(&desc->affinity_notify->work);
+		if (!schedule_work(&desc->affinity_notify->work)) {
+			/* Work was already scheduled, drop our extra ref */
+			kref_put(&desc->affinity_notify->kref,
+				 desc->affinity_notify->release);
+		}
 	}
 	irqd_set(data, IRQD_AFFINITY_SET);
 
 	return ret;
 }
 
-int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
+/**
+ * irq_update_affinity_desc - Update affinity management for an interrupt
+ * @irq:	The interrupt number to update
+ * @affinity:	Pointer to the affinity descriptor
+ *
+ * This interface can be used to configure the affinity management of
+ * interrupts which have been allocated already.
+ *
+ * There are certain limitations on when it may be used - attempts to use it
+ * for when the kernel is configured for generic IRQ reservation mode (in
+ * config GENERIC_IRQ_RESERVATION_MODE) will fail, as it may conflict with
+ * managed/non-managed interrupt accounting. In addition, attempts to use it on
+ * an interrupt which is already started or which has already been configured
+ * as managed will also fail, as these mean invalid init state or double init.
+ */
+int irq_update_affinity_desc(unsigned int irq,
+			     struct irq_affinity_desc *affinity)
+{
+	struct irq_desc *desc;
+	unsigned long flags;
+	bool activated;
+	int ret = 0;
+
+	/*
+	 * Supporting this with the reservation scheme used by x86 needs
+	 * some more thought. Fail it for now.
+	 */
+	if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
+		return -EOPNOTSUPP;
+
+	desc = irq_get_desc_buslock(irq, &flags, 0);
+	if (!desc)
+		return -EINVAL;
+
+	/* Requires the interrupt to be shut down */
+	if (irqd_is_started(&desc->irq_data)) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+
+	/* Interrupts which are already managed cannot be modified */
+	if (irqd_affinity_is_managed(&desc->irq_data)) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+
+	/*
+	 * Deactivate the interrupt. That's required to undo
+	 * anything an earlier activation has established.
+	 */
+	activated = irqd_is_activated(&desc->irq_data);
+	if (activated)
+		irq_domain_deactivate_irq(&desc->irq_data);
+
+	if (affinity->is_managed) {
+		irqd_set(&desc->irq_data, IRQD_AFFINITY_MANAGED);
+		irqd_set(&desc->irq_data, IRQD_MANAGED_SHUTDOWN);
+	}
+
+	cpumask_copy(desc->irq_common_data.affinity, &affinity->mask);
+
+	/* Restore the activation state */
+	if (activated)
+		irq_domain_activate_irq(&desc->irq_data, false);
+
+out_unlock:
+	irq_put_desc_busunlock(desc, flags);
+	return ret;
+}
+
+static int __irq_set_affinity(unsigned int irq, const struct cpumask *mask,
+			      bool force)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
@@ -345,7 +463,38 @@ int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
 	return ret;
 }
 
-int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+/**
+ * irq_set_affinity - Set the irq affinity of a given irq
+ * @irq:	Interrupt to set affinity
+ * @cpumask:	cpumask
+ *
+ * Fails if cpumask does not contain an online CPU
+ */
+int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+	return __irq_set_affinity(irq, cpumask, false);
+}
+EXPORT_SYMBOL_GPL(irq_set_affinity);
+
+/**
+ * irq_force_affinity - Force the irq affinity of a given irq
+ * @irq:	Interrupt to set affinity
+ * @cpumask:	cpumask
+ *
+ * Same as irq_set_affinity, but without checking the mask against
+ * online cpus.
+ *
+ * Solely for low level cpu hotplug code, where we need to make per
+ * cpu interrupts affine before the cpu becomes online.
+ */
+int irq_force_affinity(unsigned int irq, const struct cpumask *cpumask)
+{
+	return __irq_set_affinity(irq, cpumask, true);
+}
+EXPORT_SYMBOL_GPL(irq_force_affinity);
+
+int __irq_apply_affinity_hint(unsigned int irq, const struct cpumask *m,
+			      bool setaffinity)
 {
 	unsigned long flags;
 	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
@@ -354,12 +503,11 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
 		return -EINVAL;
 	desc->affinity_hint = m;
 	irq_put_desc_unlock(desc, flags);
-	/* set the initial affinity to prevent every interrupt being on CPU0 */
-	if (m)
+	if (m && setaffinity)
 		__irq_set_affinity(irq, m, false);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
+EXPORT_SYMBOL_GPL(__irq_apply_affinity_hint);
 
 static void irq_affinity_notify(struct work_struct *work)
 {
@@ -423,7 +571,10 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
 	if (old_notify) {
-		cancel_work_sync(&old_notify->work);
+		if (cancel_work_sync(&old_notify->work)) {
+			/* Pending work had a ref, put that one too */
+			kref_put(&old_notify->kref, old_notify->release);
+		}
 		kref_put(&old_notify->kref, old_notify->release);
 	}
 
@@ -824,7 +975,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
 	case IRQ_SET_MASK_OK_DONE:
 		irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
 		irqd_set(&desc->irq_data, flags);
-		/* fall through */
+		fallthrough;
 
 	case IRQ_SET_MASK_OK_NOCOPY:
 		flags = irqd_get_trigger_type(&desc->irq_data);
@@ -940,7 +1091,7 @@ again:
 	 * to IRQS_INPROGRESS and the irq line is masked forever.
 	 *
 	 * This also serializes the state of shared oneshot handlers
-	 * versus "desc->threads_onehsot |= action->thread_mask;" in
+	 * versus "desc->threads_oneshot |= action->thread_mask;" in
 	 * irq_wake_thread(). See the comment there which explains the
 	 * serialization.
 	 */
@@ -1028,18 +1179,22 @@ irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
 	irqreturn_t ret;
 
 	local_bh_disable();
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_disable();
 	ret = action->thread_fn(action->irq, action->dev_id);
 	if (ret == IRQ_HANDLED)
 		atomic_inc(&desc->threads_handled);
 
 	irq_finalize_oneshot(desc, action);
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+		local_irq_enable();
 	local_bh_enable();
 	return ret;
 }
 
 /*
  * Interrupts explicitly requested as threaded interrupts want to be
- * preemtible - many of them need to sleep and wait for slow busses to
+ * preemptible - many of them need to sleep and wait for slow busses to
  * complete.
  */
 static irqreturn_t irq_thread_fn(struct irq_desc *desc,
@@ -1101,6 +1256,31 @@ static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action)
 }
 
 /*
+ * Internal function to notify that a interrupt thread is ready.
+ */
+static void irq_thread_set_ready(struct irq_desc *desc,
+				 struct irqaction *action)
+{
+	set_bit(IRQTF_READY, &action->thread_flags);
+	wake_up(&desc->wait_for_threads);
+}
+
+/*
+ * Internal function to wake up a interrupt thread and wait until it is
+ * ready.
+ */
+static void wake_up_and_wait_for_irq_thread_ready(struct irq_desc *desc,
+						  struct irqaction *action)
+{
+	if (!action || !action->thread)
+		return;
+
+	wake_up_process(action->thread);
+	wait_event(desc->wait_for_threads,
+		   test_bit(IRQTF_READY, &action->thread_flags));
+}
+
+/*
  * Interrupt handler thread
  */
 static int irq_thread(void *data)
@@ -1111,14 +1291,18 @@ static int irq_thread(void *data)
 	irqreturn_t (*handler_fn)(struct irq_desc *desc,
 			struct irqaction *action);
 
-	if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD,
-					&action->thread_flags))
+	irq_thread_set_ready(desc, action);
+
+	sched_set_fifo(current);
+
+	if (force_irqthreads() && test_bit(IRQTF_FORCED_THREAD,
+					   &action->thread_flags))
 		handler_fn = irq_forced_thread_fn;
 	else
 		handler_fn = irq_thread_fn;
 
 	init_task_work(&on_exit_work, irq_thread_dtor);
-	task_work_add(current, &on_exit_work, false);
+	task_work_add(current, &on_exit_work, TWA_NONE);
 
 	irq_thread_check_affinity(desc, action);
 
@@ -1173,7 +1357,7 @@ EXPORT_SYMBOL_GPL(irq_wake_thread);
 
 static int irq_setup_forced_threading(struct irqaction *new)
 {
-	if (!force_irqthreads)
+	if (!force_irqthreads())
 		return 0;
 	if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
 		return 0;
@@ -1264,9 +1448,6 @@ static int
 setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
 {
 	struct task_struct *t;
-	struct sched_param param = {
-		.sched_priority = MAX_USER_RT_PRIO/2,
-	};
 
 	if (!secondary) {
 		t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
@@ -1274,14 +1455,11 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
 	} else {
 		t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
 				   new->name);
-		param.sched_priority -= 1;
 	}
 
 	if (IS_ERR(t))
 		return PTR_ERR(t);
 
-	sched_setscheduler_nocheck(t, SCHED_FIFO, &param);
-
 	/*
 	 * We keep the reference to the task struct even if
 	 * the thread dies to avoid that the interrupt code
@@ -1539,8 +1717,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	}
 
 	if (!shared) {
-		init_waitqueue_head(&desc->wait_for_threads);
-
 		/* Setup the type (level, edge polarity) if configured: */
 		if (new->flags & IRQF_TRIGGER_MASK) {
 			ret = __irq_set_trigger(desc,
@@ -1572,8 +1748,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 		if (new->flags & IRQF_PERCPU) {
 			irqd_set(&desc->irq_data, IRQD_PER_CPU);
 			irq_settings_set_per_cpu(desc);
+			if (new->flags & IRQF_NO_DEBUG)
+				irq_settings_set_no_debug(desc);
 		}
 
+		if (noirqdebug)
+			irq_settings_set_no_debug(desc);
+
 		if (new->flags & IRQF_ONESHOT)
 			desc->istate |= IRQS_ONESHOT;
 
@@ -1583,7 +1764,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 			irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
 		}
 
-		if (irq_settings_can_autoenable(desc)) {
+		if (!(new->flags & IRQF_NO_AUTOEN) &&
+		    irq_settings_can_autoenable(desc)) {
 			irq_startup(desc, IRQ_RESEND, IRQ_START_COND);
 		} else {
 			/*
@@ -1630,14 +1812,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 
 	irq_setup_timings(desc, new);
 
-	/*
-	 * Strictly no need to wake it up, but hung_task complains
-	 * when no hard interrupt wakes the thread up.
-	 */
-	if (new->thread)
-		wake_up_process(new->thread);
-	if (new->secondary)
-		wake_up_process(new->secondary->thread);
+	wake_up_and_wait_for_irq_thread_ready(desc, new);
+	wake_up_and_wait_for_irq_thread_ready(desc, new->secondary);
 
 	register_irq_proc(irq, desc);
 	new->dir = NULL;
@@ -1683,34 +1859,6 @@ out_mput:
 	return ret;
 }
 
-/**
- *	setup_irq - setup an interrupt
- *	@irq: Interrupt line to setup
- *	@act: irqaction for the interrupt
- *
- * Used to statically setup interrupts in the early boot process.
- */
-int setup_irq(unsigned int irq, struct irqaction *act)
-{
-	int retval;
-	struct irq_desc *desc = irq_to_desc(irq);
-
-	if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
-		return -EINVAL;
-
-	retval = irq_chip_pm_get(&desc->irq_data);
-	if (retval < 0)
-		return retval;
-
-	retval = __setup_irq(irq, desc, act);
-
-	if (retval)
-		irq_chip_pm_put(&desc->irq_data);
-
-	return retval;
-}
-EXPORT_SYMBOL_GPL(setup_irq);
-
 /*
  * Internal function to unregister an irqaction - used to free
  * regular and special interrupts that are part of the architecture.
@@ -1826,7 +1974,7 @@ static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
 	/* Last action releases resources */
 	if (!desc->action) {
 		/*
-		 * Reaquire bus lock as irq_release_resources() might
+		 * Reacquire bus lock as irq_release_resources() might
 		 * require it to deallocate resources over the slow bus.
 		 */
 		chip_bus_lock(desc);
@@ -1852,22 +2000,6 @@ static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id)
 }
 
 /**
- *	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)
-{
-	struct irq_desc *desc = irq_to_desc(irq);
-
-	if (desc && !WARN_ON(irq_settings_is_per_cpu_devid(desc)))
-		__free_irq(desc, 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
@@ -1965,9 +2097,9 @@ const void *free_nmi(unsigned int irq, void *dev_id)
  *	request_threaded_irq - allocate an interrupt line
  *	@irq: Interrupt line to allocate
  *	@handler: Function to be called when the IRQ occurs.
- *		  Primary handler for threaded interrupts
- *		  If NULL and thread_fn != NULL the default
- *		  primary handler is installed
+ *		  Primary handler for threaded interrupts.
+ *		  If handler is NULL and thread_fn != NULL
+ *		  the default primary handler is installed.
  *	@thread_fn: Function called from the irq handler thread
  *		    If NULL, no irq thread is created
  *	@irqflags: Interrupt type flags
@@ -2001,7 +2133,7 @@ const void *free_nmi(unsigned int irq, void *dev_id)
  *
  *	IRQF_SHARED		Interrupt is shared
  *	IRQF_TRIGGER_*		Specify active edge(s) or level
- *
+ *	IRQF_ONESHOT		Run thread_fn with interrupt line masked
  */
 int request_threaded_irq(unsigned int irq, irq_handler_t handler,
 			 irq_handler_t thread_fn, unsigned long irqflags,
@@ -2020,10 +2152,15 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
 	 * which interrupt is which (messes up the interrupt freeing
 	 * logic etc).
 	 *
+	 * Also shared interrupts do not go well with disabling auto enable.
+	 * The sharing interrupt might request it while it's still disabled
+	 * and then wait for interrupts forever.
+	 *
 	 * Also IRQF_COND_SUSPEND only makes sense for shared interrupts and
 	 * it cannot be set along with IRQF_NO_SUSPEND.
 	 */
 	if (((irqflags & IRQF_SHARED) && !dev_id) ||
+	    ((irqflags & IRQF_SHARED) && (irqflags & IRQF_NO_AUTOEN)) ||
 	    (!(irqflags & IRQF_SHARED) && (irqflags & IRQF_COND_SUSPEND)) ||
 	    ((irqflags & IRQF_NO_SUSPEND) && (irqflags & IRQF_COND_SUSPEND)))
 		return -EINVAL;
@@ -2179,7 +2316,8 @@ int request_nmi(unsigned int irq, irq_handler_t handler,
 
 	desc = irq_to_desc(irq);
 
-	if (!desc || irq_settings_can_autoenable(desc) ||
+	if (!desc || (irq_settings_can_autoenable(desc) &&
+	    !(irqflags & IRQF_NO_AUTOEN)) ||
 	    !irq_settings_can_request(desc) ||
 	    WARN_ON(irq_settings_is_per_cpu_devid(desc)) ||
 	    !irq_supports_nmi(desc))
@@ -2656,6 +2794,8 @@ int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
 
 	do {
 		chip = irq_data_get_irq_chip(data);
+		if (WARN_ON_ONCE(!chip))
+			return -ENODEV;
 		if (chip->irq_get_irqchip_state)
 			break;
 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
@@ -2674,7 +2814,7 @@ int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which,
  *	irq_get_irqchip_state - returns the irqchip state of a interrupt.
  *	@irq: Interrupt line that is forwarded to a VM
  *	@which: One of IRQCHIP_STATE_* the caller wants to know about
- *	@state: a pointer to a boolean where the state is to be storeed
+ *	@state: a pointer to a boolean where the state is to be stored
  *
  *	This call snapshots the internal irqchip state of an
  *	interrupt, returning into @state the bit corresponding to
@@ -2713,7 +2853,7 @@ EXPORT_SYMBOL_GPL(irq_get_irqchip_state);
  *	This call sets the internal irqchip state of an interrupt,
  *	depending on the value of @which.
  *
- *	This function should be called with preemption disabled if the
+ *	This function should be called with migration disabled if the
  *	interrupt controller has per-cpu registers.
  */
 int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
@@ -2733,6 +2873,10 @@ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
 
 	do {
 		chip = irq_data_get_irq_chip(data);
+		if (WARN_ON_ONCE(!chip)) {
+			err = -ENODEV;
+			goto out_unlock;
+		}
 		if (chip->irq_set_irqchip_state)
 			break;
 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
@@ -2745,7 +2889,46 @@ int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which,
 	if (data)
 		err = chip->irq_set_irqchip_state(data, which, val);
 
+out_unlock:
 	irq_put_desc_busunlock(desc, flags);
 	return err;
 }
 EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
+
+/**
+ * irq_has_action - Check whether an interrupt is requested
+ * @irq:	The linux irq number
+ *
+ * Returns: A snapshot of the current state
+ */
+bool irq_has_action(unsigned int irq)
+{
+	bool res;
+
+	rcu_read_lock();
+	res = irq_desc_has_action(irq_to_desc(irq));
+	rcu_read_unlock();
+	return res;
+}
+EXPORT_SYMBOL_GPL(irq_has_action);
+
+/**
+ * irq_check_status_bit - Check whether bits in the irq descriptor status are set
+ * @irq:	The linux irq number
+ * @bitmask:	The bitmask to evaluate
+ *
+ * Returns: True if one of the bits in @bitmask is set
+ */
+bool irq_check_status_bit(unsigned int irq, unsigned int bitmask)
+{
+	struct irq_desc *desc;
+	bool res = false;
+
+	rcu_read_lock();
+	desc = irq_to_desc(irq);
+	if (desc)
+		res = !!(desc->status_use_accessors & bitmask);
+	rcu_read_unlock();
+	return res;
+}
+EXPORT_SYMBOL_GPL(irq_check_status_bit);