[PATCH v10 0/1] genirq/devres: Add error handling in devm_request_threaded_irq() and devm_request_any_context_irq()

[PATCH v10 0/1] genirq/devres: Add error handling in devm_request_threaded_irq() and devm_request_any_context_irq()

[Pan Chuang]

There are over 700 calls to devm_request_threaded_irq() and more than 1000
calls to devm_request_irq() in the kernel. Currently, most drivers implement
repetitive and inconsistent error handling for these functions:

1. Over 2000 lines of code are dedicated to error messages
2. Analysis shows 519 unique error messages with 323 variants after normalization
3. 186 messages provide no useful debugging information
4. Only a small fraction deliver meaningful error context

As tglx pointed out:
  "It's not a general allocator like kmalloc(). It's specialized and in the
   vast majority of cases failing to request the interrupt causes the device
   probe to fail. So having proper and consistent information why the device
   cannot be used is useful."

This patch implements a standardized error reporting approach[1]:

1. Renames existing functions to __devm_request_threaded_irq() and
   __devm_request_any_context_irq()

2. Adds devm_request_result() helper to unify error reporting:  
   a) Provides consistent diagnostic logging via dev_err_probe() on failure  
   b) Returns early with success code if no error occurred
 
3. Creates new devm_request_threaded_irq() and devm_request_any_context_irq()
   that:
   a) Invoke the underscore-prefixed variants
   b) Invokes devm_request_result() for centralized logging

The new error format provides complete debugging context:
  "<device>: error -<errcode>: request_irq(<irq>) <handler> <thread_fn> <devname>"

Example from our QEMU testing:
  test_irq_device: error -EINVAL: request_irq(1001) test_handler [test_irq] test_thread_fn [test_irq] irq-1001-failure

Based on the v9, add devm_request_result() helper.
https://lore.kernel.org/all/20250730062554.269151-2-panchuang@vivo.com/

[1]https://lore.kernel.org/all/87qzy9tvso.ffs@tglx/

Pan Chuang (1):
  genirq/devres: Add err handling in devm_request_threaded_irq() and
    devm_request_any_context_irq()

 kernel/irq/devres.c | 123 ++++++++++++++++++++++++++++++--------------
 1 file changed, 83 insertions(+), 40 deletions(-)

-- 
2.34.1

[PATCH v10 1/1] genirq/devres: Add err handling in devm_request_threaded_irq() and devm_request_any_context_irq()

[Pan Chuang]

The devm_request_threaded_irq() and devm_request_any_context_irq() currently
don't print any error when interrupt registration fails. This forces each
driver to implement redundant error logging - over 2,000 lines of error
messages exist across drivers. Additionally, when upper-layer functions
propagate these errors without logging, critical debugging information is lost.

Add devm_request_result() helper to unify error reporting via dev_err_probe(),
Use it in devm_request_threaded_irq() and devm_request_any_context_irq()
printing device name, IRQ number, handler functions, and error code on failure
automatically.

Co-developed-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Pan Chuang <panchuang@vivo.com>
---
 kernel/irq/devres.c | 123 ++++++++++++++++++++++++++++++--------------
 1 file changed, 83 insertions(+), 40 deletions(-)

diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index eb16a58e0322..90290e3b9699 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 +71,46 @@ 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 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_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().  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.
  *
- *	If an IRQ 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: 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 +135,38 @@ 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 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
+ *
+ * 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.
+ *
+ * If an IRQ 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);
 
 /**
-- 
2.34.1

Re: [PATCH v10 1/1] genirq/devres: Add err handling in devm_request_threaded_irq() and devm_request_any_context_irq()

[PanChuang]

Hi tglx,

Gentle ping.

Thanks,

Pan Chuang

[tip: irq/core] genirq/devres: Add error handling in devm_request_*_irq()

[tip-bot2 for Pan Chuang]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     55b48e23f5c4b6f5ca9b7ab09599b17dcf501c10
Gitweb:        https://git.kernel.org/tip/55b48e23f5c4b6f5ca9b7ab09599b17dcf501c10
Author:        Pan Chuang <panchuang@vivo.com>
AuthorDate:    Tue, 05 Aug 2025 17:29:22 +08:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sun, 24 Aug 2025 13:00:45 +02:00

genirq/devres: Add error handling in devm_request_*_irq()

devm_request_threaded_irq() and devm_request_any_context_irq() currently
don't print any error message when interrupt registration fails.

This forces each driver to implement redundant error logging - over 2,000
lines of error messages exist across drivers. Additionally, when
upper-layer functions propagate these errors without logging, critical
debugging information is lost.

Add devm_request_result() helper to unify error reporting via dev_err_probe(),

Use it in devm_request_threaded_irq() and devm_request_any_context_irq()
printing device name, IRQ number, handler functions, and error code on failure
automatically.

Co-developed-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250805092922.135500-2-panchuang@vivo.com

---
 kernel/irq/devres.c | 127 +++++++++++++++++++++++++++++--------------
 1 file changed, 87 insertions(+), 40 deletions(-)

diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index eb16a58..b411886 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);
 
 /**