kernel/irq: Extend lockdep class for request mutex

The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch

11 files changed, 75 insertions, 35 deletions

diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c
index 44cbf4c12ea1..df95102e732c 100644
--- a/arch/powerpc/sysdev/fsl_msi.c
+++ b/arch/powerpc/sysdev/fsl_msi.c
@@ -354,6 +354,7 @@ static int fsl_of_msi_remove(struct platform_device *ofdev)
 }
 
 static struct lock_class_key fsl_msi_irq_class;
+static struct lock_class_key fsl_msi_irq_request_class;
 
 static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
                                int offset, int irq_index)
@@ -373,7 +374,8 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
                 dev_err(&dev->dev, "No memory for MSI cascade data\n");
                 return -ENOMEM;
         }
-        irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class);
+        irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class,
+                              &fsl_msi_irq_request_class);
         cascade_data->index = offset;
         cascade_data->msi_data = msi;
         cascade_data->virq = virt_msir;
diff --git a/drivers/gpio/gpio-bcm-kona.c b/drivers/gpio/gpio-bcm-kona.c
index dfcf56ee3c61..76861a00bb92 100644
--- a/drivers/gpio/gpio-bcm-kona.c
+++ b/drivers/gpio/gpio-bcm-kona.c
@@ -522,6 +522,7 @@ static struct of_device_id const bcm_kona_gpio_of_match[] = {
  * category than their parents, so it won't report false recursion.
  */
 static struct lock_class_key gpio_lock_class;
+static struct lock_class_key gpio_request_class;
 
 static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
                                  irq_hw_number_t hwirq)
@@ -531,7 +532,7 @@ static int bcm_kona_gpio_irq_map(struct irq_domain *d, unsigned int irq,
         ret = irq_set_chip_data(irq, d->host_data);
         if (ret < 0)
                 return ret;
-        irq_set_lockdep_class(irq, &gpio_lock_class);
+        irq_set_lockdep_class(irq, &gpio_lock_class, &gpio_request_class);
         irq_set_chip_and_handler(irq, &bcm_gpio_irq_chip, handle_simple_irq);
         irq_set_noprobe(irq);
 
diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
index 545d43a587b7..5b24801bffef 100644
--- a/drivers/gpio/gpio-brcmstb.c
+++ b/drivers/gpio/gpio-brcmstb.c
@@ -327,6 +327,7 @@ static struct brcmstb_gpio_bank *brcmstb_gpio_hwirq_to_bank(
  * category than their parents, so it won't report false recursion.
  */
 static struct lock_class_key brcmstb_gpio_irq_lock_class;
+static struct lock_class_key brcmstb_gpio_irq_request_class;
 
 
 static int brcmstb_gpio_irq_map(struct irq_domain *d, unsigned int irq,
@@ -346,7 +347,8 @@ static int brcmstb_gpio_irq_map(struct irq_domain *d, unsigned int irq,
         ret = irq_set_chip_data(irq, &bank->gc);
         if (ret < 0)
                 return ret;
-        irq_set_lockdep_class(irq, &brcmstb_gpio_irq_lock_class);
+        irq_set_lockdep_class(irq, &brcmstb_gpio_irq_lock_class,
+                              &brcmstb_gpio_irq_lock_class);
         irq_set_chip_and_handler(irq, &priv->irq_chip, handle_level_irq);
         irq_set_noprobe(irq);
         return 0;
diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
index 8db47f671708..02fa8fe2292a 100644
--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -565,6 +565,7 @@ static const struct dev_pm_ops tegra_gpio_pm_ops = {
  * than their parents, so it won't report false recursion.
  */
 static struct lock_class_key gpio_lock_class;
+static struct lock_class_key gpio_request_class;
 
 static int tegra_gpio_probe(struct platform_device *pdev)
 {
@@ -670,7 +671,8 @@ static int tegra_gpio_probe(struct platform_device *pdev)
 
                 bank = &tgi->bank_info[GPIO_BANK(gpio)];
 
-                irq_set_lockdep_class(irq, &gpio_lock_class);
+                irq_set_lockdep_class(irq, &gpio_lock_class,
+                                      &gpio_request_class);
                 irq_set_chip_data(irq, bank);
                 irq_set_chip_and_handler(irq, &tgi->ic, handle_simple_irq);
         }
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index aad84a6306c4..44332b793718 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -73,7 +73,8 @@ LIST_HEAD(gpio_devices);
 
 static void gpiochip_free_hogs(struct gpio_chip *chip);
 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
-                                struct lock_class_key *key);
+                                struct lock_class_key *lock_key,
+                                struct lock_class_key *request_key);
 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
@@ -1100,7 +1101,8 @@ static void gpiochip_setup_devs(void)
 }
 
 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
-                               struct lock_class_key *key)
+                               struct lock_class_key *lock_key,
+                               struct lock_class_key *request_key)
 {
         unsigned long   flags;
         int             status = 0;
@@ -1246,7 +1248,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
         if (status)
                 goto err_remove_from_list;
 
-        status = gpiochip_add_irqchip(chip, key);
+        status = gpiochip_add_irqchip(chip, lock_key, request_key);
         if (status)
                 goto err_remove_chip;
 
@@ -1632,7 +1634,7 @@ int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
          * This lock class tells lockdep that GPIO irqs are in a different
          * category than their parents, so it won't report false recursion.
          */
-        irq_set_lockdep_class(irq, chip->irq.lock_key);
+        irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
         irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
         /* Chips that use nested thread handlers have them marked */
         if (chip->irq.threaded)
@@ -1712,10 +1714,12 @@ static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
 /**
  * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
  * @gpiochip: the GPIO chip to add the IRQ chip to
- * @lock_key: lockdep class
+ * @lock_key: lockdep class for IRQ lock
+ * @request_key: lockdep class for IRQ request
  */
 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
-                                struct lock_class_key *lock_key)
+                                struct lock_class_key *lock_key,
+                                struct lock_class_key *request_key)
 {
         struct irq_chip *irqchip = gpiochip->irq.chip;
         const struct irq_domain_ops *ops;
@@ -1753,6 +1757,7 @@ static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
         gpiochip->to_irq = gpiochip_to_irq;
         gpiochip->irq.default_type = type;
         gpiochip->irq.lock_key = lock_key;
+        gpiochip->irq.request_key = request_key;
 
         if (gpiochip->irq.domain_ops)
                 ops = gpiochip->irq.domain_ops;
@@ -1850,7 +1855,8 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
  * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
  * to have the core avoid setting up any default type in the hardware.
  * @threaded: whether this irqchip uses a nested thread handler
- * @lock_key: lockdep class
+ * @lock_key: lockdep class for IRQ lock
+ * @request_key: lockdep class for IRQ request
  *
  * This function closely associates a certain irqchip with a certain
  * gpiochip, providing an irq domain to translate the local IRQs to
@@ -1872,7 +1878,8 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
                              irq_flow_handler_t handler,
                              unsigned int type,
                              bool threaded,
-                             struct lock_class_key *lock_key)
+                             struct lock_class_key *lock_key,
+                             struct lock_class_key *request_key)
 {
         struct device_node *of_node;
 
@@ -1913,6 +1920,7 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
         gpiochip->irq.default_type = type;
         gpiochip->to_irq = gpiochip_to_irq;
         gpiochip->irq.lock_key = lock_key;
+        gpiochip->irq.request_key = request_key;
         gpiochip->irq.domain = irq_domain_add_simple(of_node,
                                         gpiochip->ngpio, first_irq,
                                         &gpiochip_domain_ops, gpiochip);
@@ -1940,7 +1948,8 @@ EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
 #else /* CONFIG_GPIOLIB_IRQCHIP */
 
 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
-                                       struct lock_class_key *key)
+                                       struct lock_class_key *lock_key,
+                                       struct lock_class_key *request_key)
 {
         return 0;
 }
diff --git a/drivers/irqchip/irq-renesas-intc-irqpin.c b/drivers/irqchip/irq-renesas-intc-irqpin.c
index 06f29cf5018a..cee59fe1321c 100644
--- a/drivers/irqchip/irq-renesas-intc-irqpin.c
+++ b/drivers/irqchip/irq-renesas-intc-irqpin.c
@@ -342,6 +342,9 @@ static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id)
  */
 static struct lock_class_key intc_irqpin_irq_lock_class;
 
+/* And this is for the request mutex */
+static struct lock_class_key intc_irqpin_irq_request_class;
+
 static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq,
                                       irq_hw_number_t hw)
 {
@@ -352,7 +355,8 @@ static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq,
 
         intc_irqpin_dbg(&p->irq[hw], "map");
         irq_set_chip_data(virq, h->host_data);
-        irq_set_lockdep_class(virq, &intc_irqpin_irq_lock_class);
+        irq_set_lockdep_class(virq, &intc_irqpin_irq_lock_class,
+                              &intc_irqpin_irq_request_class);
         irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
         return 0;
 }
diff --git a/drivers/mfd/arizona-irq.c b/drivers/mfd/arizona-irq.c
index 09cf3699e354..a307832d7e45 100644
--- a/drivers/mfd/arizona-irq.c
+++ b/drivers/mfd/arizona-irq.c
@@ -184,6 +184,7 @@ static struct irq_chip arizona_irq_chip = {
 };
 
 static struct lock_class_key arizona_irq_lock_class;
+static struct lock_class_key arizona_irq_request_class;
 
 static int arizona_irq_map(struct irq_domain *h, unsigned int virq,
                               irq_hw_number_t hw)
@@ -191,7 +192,8 @@ static int arizona_irq_map(struct irq_domain *h, unsigned int virq,
         struct arizona *data = h->host_data;
 
         irq_set_chip_data(virq, data);
-        irq_set_lockdep_class(virq, &arizona_irq_lock_class);
+        irq_set_lockdep_class(virq, &arizona_irq_lock_class,
+                &arizona_irq_request_class);
         irq_set_chip_and_handler(virq, &arizona_irq_chip, handle_simple_irq);
         irq_set_nested_thread(virq, 1);
         irq_set_noprobe(virq);
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index e6cd8de793e2..3501491e5bfc 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -222,6 +222,9 @@ static enum pin_config_param pcs_bias[] = {
  */
 static struct lock_class_key pcs_lock_class;
 
+/* Class for the IRQ request mutex */
+static struct lock_class_key pcs_request_class;
+
 /*
  * REVISIT: Reads and writes could eventually use regmap or something
  * generic. But at least on omaps, some mux registers are performance
@@ -1486,7 +1489,7 @@ static int pcs_irqdomain_map(struct irq_domain *d, unsigned int irq,
         irq_set_chip_data(irq, pcs_soc);
         irq_set_chip_and_handler(irq, &pcs->chip,
                                  handle_level_irq);
-        irq_set_lockdep_class(irq, &pcs_lock_class);
+        irq_set_lockdep_class(irq, &pcs_lock_class, &pcs_request_class);
         irq_set_noprobe(irq);
 
         return 0;
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 55e672592fa9..7258cd676df4 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -66,9 +66,10 @@ struct gpio_irq_chip {
         /**
          * @lock_key:
          *
-         * Per GPIO IRQ chip lockdep class.
+         * Per GPIO IRQ chip lockdep classes.
          */
         struct lock_class_key *lock_key;
+        struct lock_class_key *request_key;
 
         /**
          * @parent_handler:
@@ -323,7 +324,8 @@ extern const char *gpiochip_is_requested(struct gpio_chip *chip,
 
 /* add/remove chips */
 extern int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
-                                      struct lock_class_key *lock_key);
+                                      struct lock_class_key *lock_key,
+                                      struct lock_class_key *request_key);
 
 /**
  * gpiochip_add_data() - register a gpio_chip
@@ -350,11 +352,13 @@ extern int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
  */
 #ifdef CONFIG_LOCKDEP
 #define gpiochip_add_data(chip, data) ({                \
-                static struct lock_class_key key;       \
-                gpiochip_add_data_with_key(chip, data, &key);   \
+                static struct lock_class_key lock_key;  \
+                static struct lock_class_key request_key;         \
+                gpiochip_add_data_with_key(chip, data, &lock_key, \
+                                           &request_key);         \
         })
 #else
-#define gpiochip_add_data(chip, data) gpiochip_add_data_with_key(chip, data, NULL)
+#define gpiochip_add_data(chip, data) gpiochip_add_data_with_key(chip, data, NULL, NULL)
 #endif
 
 static inline int gpiochip_add(struct gpio_chip *chip)
@@ -429,7 +433,8 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
                              irq_flow_handler_t handler,
                              unsigned int type,
                              bool threaded,
-                             struct lock_class_key *lock_key);
+                             struct lock_class_key *lock_key,
+                             struct lock_class_key *request_key);
 
 #ifdef CONFIG_LOCKDEP
 
@@ -445,10 +450,12 @@ static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
                                        irq_flow_handler_t handler,
                                        unsigned int type)
 {
-        static struct lock_class_key key;
+        static struct lock_class_key lock_key;
+        static struct lock_class_key request_key;
 
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, false, &key);
+                                        handler, type, false,
+                                        &lock_key, &request_key);
 }
 
 static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
@@ -458,10 +465,12 @@ static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
                           unsigned int type)
 {
 
-        static struct lock_class_key key;
+        static struct lock_class_key lock_key;
+        static struct lock_class_key request_key;
 
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, true, &key);
+                                        handler, type, true,
+                                        &lock_key, &request_key);
 }
 #else
 static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
@@ -471,7 +480,7 @@ static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
                                        unsigned int type)
 {
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, false, NULL);
+                                        handler, type, false, NULL, NULL);
 }
 
 static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
@@ -481,7 +490,7 @@ static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
                           unsigned int type)
 {
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, true, NULL);
+                                        handler, type, true, NULL, NULL);
 }
 #endif /* CONFIG_LOCKDEP */
 
diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 39fb3700f7a9..25b33b664537 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -255,12 +255,15 @@ static inline bool irq_is_percpu_devid(unsigned int irq)
 }
 
 static inline void
-irq_set_lockdep_class(unsigned int irq, struct lock_class_key *class)
+irq_set_lockdep_class(unsigned int irq, struct lock_class_key *lock_class,
+                      struct lock_class_key *request_class)
 {
         struct irq_desc *desc = irq_to_desc(irq);
 
-        if (desc)
-                lockdep_set_class(&desc->lock, class);
+        if (desc) {
+                lockdep_set_class(&desc->lock, lock_class);
+                lockdep_set_class(&desc->request_mutex, request_class);
+        }
 }
 
 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index c26c5bb6b491..508c03dfef25 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -364,10 +364,11 @@ irq_get_domain_generic_chip(struct irq_domain *d, unsigned int hw_irq)
 EXPORT_SYMBOL_GPL(irq_get_domain_generic_chip);
 
 /*
- * Separate lockdep class for interrupt chip which can nest irq_desc
- * lock.
+ * Separate lockdep classes for interrupt chip which can nest irq_desc
+ * lock and request mutex.
  */
 static struct lock_class_key irq_nested_lock_class;
+static struct lock_class_key irq_nested_request_class;
 
 /*
  * irq_map_generic_chip - Map a generic chip for an irq domain
@@ -409,7 +410,8 @@ int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
         set_bit(idx, &gc->installed);
 
         if (dgc->gc_flags & IRQ_GC_INIT_NESTED_LOCK)
-                irq_set_lockdep_class(virq, &irq_nested_lock_class);
+                irq_set_lockdep_class(virq, &irq_nested_lock_class,
+                                      &irq_nested_request_class);
 
         if (chip->irq_calc_mask)
                 chip->irq_calc_mask(data);
@@ -479,7 +481,8 @@ void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
                         continue;
 
                 if (flags & IRQ_GC_INIT_NESTED_LOCK)
-                        irq_set_lockdep_class(i, &irq_nested_lock_class);
+                        irq_set_lockdep_class(i, &irq_nested_lock_class,
+                                              &irq_nested_request_class);
 
                 if (!(flags & IRQ_GC_NO_MASK)) {
                         struct irq_data *d = irq_get_irq_data(i);