From: Grygorii Strashko Date: Thu, 25 Jun 2015 17:30:50 +0000 (+0300) Subject: gpiolib: irqchip: prevent driver unloading if gpio is used as irq only X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=5b76e79c77264899;p=deliverable%2Flinux.git gpiolib: irqchip: prevent driver unloading if gpio is used as irq only Now nothing prevents GPIO driver from being unloaded if its gpios were requested as GPIO IRQs only (without calling gpio_request()). Hence, add calls of try_module_get()/module_put() into gpiochip_irq_reqres/relres() to track such scenario properly. Cc: Johan Hovold Signed-off-by: Grygorii Strashko Reviewed-by: Alexandre Courbot Signed-off-by: Linus Walleij --- diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index b1b08b3fa626..debd7c56187d 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -522,10 +522,14 @@ static int gpiochip_irq_reqres(struct irq_data *d) { struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + if (!try_module_get(chip->owner)) + return -ENODEV; + if (gpiochip_lock_as_irq(chip, d->hwirq)) { chip_err(chip, "unable to lock HW IRQ %lu for IRQ\n", d->hwirq); + module_put(chip->owner); return -EINVAL; } return 0; @@ -536,6 +540,7 @@ static void gpiochip_irq_relres(struct irq_data *d) struct gpio_chip *chip = irq_data_get_irq_chip_data(d); gpiochip_unlock_as_irq(chip, d->hwirq); + module_put(chip->owner); } static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)