Commit 00acc3dc authored Jan 12, 2015 by Johan Hovold Committed by Linus Walleij Jan 14, 2015

gpio: fix memory leak and sleep-while-atomic



Fix memory leak and sleep-while-atomic in gpiochip_remove.

The memory leak was introduced by afa82fab ("gpio / ACPI: Move event
handling registration to gpiolib irqchip helpers") that moved the
release of acpi interrupt resources to gpiochip_irqchip_remove, but by
then the resources are no longer accessible as the acpi_gpio_chip has
already been freed by acpi_gpiochip_remove.

Note that this also fixes a few potential sleep-while-atomics, which has
been around since 14250520 ("gpio: add IRQ chip helpers in gpiolib")
when the call to gpiochip_irqchip_remove while holding a spinlock was
added (a couple of irq-domain paths can end up grabbing mutexes).

Fixes: afa82fab ("gpio / ACPI: Move event handling registration to
gpiolib irqchip helpers")
Fixes: 14250520 ("gpio: add IRQ chip helpers in gpiolib")
Cc: stable <stable@vger.kernel.org>

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

parent 05aa5203

drivers/gpio/gpiolib.c

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -327,11 +327,12 @@ void gpiochip_remove(struct gpio_chip *chip)
	unsigned long flags;		unsigned long flags;
	unsigned id;		unsigned id;

			gpiochip_irqchip_remove(chip);

	acpi_gpiochip_remove(chip);		acpi_gpiochip_remove(chip);

	spin_lock_irqsave(&gpio_lock, flags);		spin_lock_irqsave(&gpio_lock, flags);

	gpiochip_irqchip_remove(chip);
	gpiochip_remove_pin_ranges(chip);		gpiochip_remove_pin_ranges(chip);
	of_gpiochip_remove(chip);		of_gpiochip_remove(chip);

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