Merge tag 'irq-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq core updates from Thomas Gleixner:
 "A set of updates for the interrupt core subsystem:

   - Introduce irq_chip_[startup|shutdown]_parent() to prepare for
     addressing a few short comings in the PCI/MSI interrupt subsystem.

     It allows to utilize the interrupt chip startup/shutdown callbacks
     for initializing the interrupt chip hierarchy properly on certain
     RISCV implementations and provides a mechanism to reduce the
     overhead of masking and unmasking PCI/MSI interrupts during
     operation when the underlying MSI provider can mask the interrupt.

     The actual usage comes with the interrupt driver pull request.

   - Add generic error handling for devm_request_*_irq()

     This allows to remove the zoo of random error printk's all over the
     usage sites.

   - Add a mechanism to warn about long-running interrupt handlers

     Long running interrupt handlers can introduce latencies and
     tracking them down is a tedious task. The tracking has to be
     enabled with a threshold on the kernel command line and utilizes a
     static branch to remove the overhead when disabled.

   - Update and extend the selftests which validate the CPU hotplug
     interrupt migration logic

   - Allow dropping the per CPU softirq lock on PREEMPT_RT kernels,
     which causes contention and latencies all over the place.

     The serialization requirements have been pushed down into the
     actual affected usage sites already.

   - The usual small cleanups and improvements"

* tag 'irq-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT
  softirq: Provide a handshake for canceling tasklets via polling
  genirq/test: Ensure CPU 1 is online for hotplug test
  genirq/test: Drop CONFIG_GENERIC_IRQ_MIGRATION assumptions
  genirq/test: Depend on SPARSE_IRQ
  genirq/test: Fail early if interrupt request fails
  genirq/test: Factor out fake-virq setup
  genirq/test: Select IRQ_DOMAIN
  genirq/test: Fix depth tests on architectures with NOREQUEST by default.
  genirq: Add support for warning on long-running interrupt handlers
  genirq/devres: Add error handling in devm_request_*_irq()
  genirq: Add irq_chip_(startup/shutdown)_parent()
  genirq: Remove GENERIC_IRQ_LEGACY

1 files changed, 87 insertions, 40 deletions

diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index eb16a58e0322..b41188698622 100644
--- a/kernel/irq/devres.c
+++ b/kernel/irq/devres.c
@@ -30,29 +30,22 @@ static int devm_irq_match(struct device *dev, void *res, void *data)
 	return this->irq == match->irq && this->dev_id == match->dev_id;
 }
 
-/**
- *	devm_request_threaded_irq - allocate an interrupt line for a managed device
- *	@dev: device to request interrupt for
- *	@irq: Interrupt line to allocate
- *	@handler: Function to be called when the IRQ occurs
- *	@thread_fn: function to be called in a threaded interrupt context. NULL
- *		    for devices which handle everything in @handler
- *	@irqflags: Interrupt type flags
- *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
- *	@dev_id: A cookie passed back to the handler function
- *
- *	Except for the extra @dev argument, this function takes the
- *	same arguments and performs the same function as
- *	request_threaded_irq().  IRQs requested with this function will be
- *	automatically freed on driver detach.
- *
- *	If an IRQ allocated with this function needs to be freed
- *	separately, devm_free_irq() must be used.
- */
-int devm_request_threaded_irq(struct device *dev, unsigned int irq,
-			      irq_handler_t handler, irq_handler_t thread_fn,
-			      unsigned long irqflags, const char *devname,
-			      void *dev_id)
+static int devm_request_result(struct device *dev, int rc, unsigned int irq,
+			       irq_handler_t handler, irq_handler_t thread_fn,
+			       const char *devname)
+{
+	if (rc >= 0)
+		return rc;
+
+	return dev_err_probe(dev, rc, "request_irq(%u) %ps %ps %s\n",
+			     irq, handler, thread_fn, devname ? : "");
+}
+
+static int __devm_request_threaded_irq(struct device *dev, unsigned int irq,
+				       irq_handler_t handler,
+				       irq_handler_t thread_fn,
+				       unsigned long irqflags,
+				       const char *devname, void *dev_id)
 {
 	struct irq_devres *dr;
 	int rc;
@@ -78,28 +71,48 @@ int devm_request_threaded_irq(struct device *dev, unsigned int irq,
 
 	return 0;
 }
-EXPORT_SYMBOL(devm_request_threaded_irq);
 
 /**
- *	devm_request_any_context_irq - allocate an interrupt line for a managed device
- *	@dev: device to request interrupt for
- *	@irq: Interrupt line to allocate
- *	@handler: Function to be called when the IRQ occurs
- *	@irqflags: Interrupt type flags
- *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
- *	@dev_id: A cookie passed back to the handler function
+ * devm_request_threaded_irq - allocate an interrupt line for a managed device with error logging
+ * @dev:	Device to request interrupt for
+ * @irq:	Interrupt line to allocate
+ * @handler:	Function to be called when the interrupt occurs
+ * @thread_fn:	Function to be called in a threaded interrupt context. NULL
+ *		for devices which handle everything in @handler
+ * @irqflags:	Interrupt type flags
+ * @devname:	An ascii name for the claiming device, dev_name(dev) if NULL
+ * @dev_id:	A cookie passed back to the handler function
  *
- *	Except for the extra @dev argument, this function takes the
- *	same arguments and performs the same function as
- *	request_any_context_irq().  IRQs requested with this function will be
- *	automatically freed on driver detach.
+ * Except for the extra @dev argument, this function takes the same
+ * arguments and performs the same function as request_threaded_irq().
+ * Interrupts requested with this function will be automatically freed on
+ * driver detach.
+ *
+ * If an interrupt allocated with this function needs to be freed
+ * separately, devm_free_irq() must be used.
+ *
+ * When the request fails, an error message is printed with contextual
+ * information (device name, interrupt number, handler functions and
+ * error code). Don't add extra error messages at the call sites.
  *
- *	If an IRQ allocated with this function needs to be freed
- *	separately, devm_free_irq() must be used.
+ * Return: 0 on success or a negative error number.
  */
-int devm_request_any_context_irq(struct device *dev, unsigned int irq,
-			      irq_handler_t handler, unsigned long irqflags,
-			      const char *devname, void *dev_id)
+int devm_request_threaded_irq(struct device *dev, unsigned int irq,
+			      irq_handler_t handler, irq_handler_t thread_fn,
+			      unsigned long irqflags, const char *devname,
+			      void *dev_id)
+{
+	int rc = __devm_request_threaded_irq(dev, irq, handler, thread_fn,
+					     irqflags, devname, dev_id);
+
+	return devm_request_result(dev, rc, irq, handler, thread_fn, devname);
+}
+EXPORT_SYMBOL(devm_request_threaded_irq);
+
+static int __devm_request_any_context_irq(struct device *dev, unsigned int irq,
+					  irq_handler_t handler,
+					  unsigned long irqflags,
+					  const char *devname, void *dev_id)
 {
 	struct irq_devres *dr;
 	int rc;
@@ -124,6 +137,40 @@ int devm_request_any_context_irq(struct device *dev, unsigned int irq,
 
 	return rc;
 }
+
+/**
+ * devm_request_any_context_irq - allocate an interrupt line for a managed device with error logging
+ * @dev:	Device to request interrupt for
+ * @irq:	Interrupt line to allocate
+ * @handler:	Function to be called when the interrupt occurs
+ * @irqflags:	Interrupt type flags
+ * @devname:	An ascii name for the claiming device, dev_name(dev) if NULL
+ * @dev_id:	A cookie passed back to the handler function
+ *
+ * Except for the extra @dev argument, this function takes the same
+ * arguments and performs the same function as request_any_context_irq().
+ * Interrupts requested with this function will be automatically freed on
+ * driver detach.
+ *
+ * If an interrupt allocated with this function needs to be freed
+ * separately, devm_free_irq() must be used.
+ *
+ * When the request fails, an error message is printed with contextual
+ * information (device name, interrupt number, handler functions and
+ * error code). Don't add extra error messages at the call sites.
+ *
+ * Return: IRQC_IS_HARDIRQ or IRQC_IS_NESTED on success, or a negative error
+ * number.
+ */
+int devm_request_any_context_irq(struct device *dev, unsigned int irq,
+				 irq_handler_t handler, unsigned long irqflags,
+				 const char *devname, void *dev_id)
+{
+	int rc = __devm_request_any_context_irq(dev, irq, handler, irqflags,
+						devname, dev_id);
+
+	return devm_request_result(dev, rc, irq, handler, NULL, devname);
+}
 EXPORT_SYMBOL(devm_request_any_context_irq);
 
 /**