[PATCH] gpio: remove GPIO device from the list unconditionally in error path

[PATCH] gpio: remove GPIO device from the list unconditionally in error path

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Since commit 48e1b4d369cf ("gpiolib: remove the GPIO device from the list
when it's unregistered") we remove the GPIO device entry from the global
list (used to order devices by their GPIO ranges) when unregistering the
chip, not when releasing the device. It will not happen when the last
reference is put anymore. This means, we need to remove it in error path
in gpiochip_add_data_with_key() unconditionally, without checking if the
device's .release() callback is set.

Fixes: 48e1b4d369cf ("gpiolib: remove the GPIO device from the list when it's unregistered")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/gpio/gpiolib.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d50a786f8176..d52b340562ce 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1005,15 +1005,15 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 err_free_gpiochip_mask:
 	gpiochip_remove_pin_ranges(gc);
 	gpiochip_free_valid_mask(gc);
+err_remove_from_list:
+	spin_lock_irqsave(&gpio_lock, flags);
+	list_del(&gdev->list);
+	spin_unlock_irqrestore(&gpio_lock, flags);
 	if (gdev->dev.release) {
 		/* release() has been registered by gpiochip_setup_dev() */
 		gpio_device_put(gdev);
 		goto err_print_message;
 	}
-err_remove_from_list:
-	spin_lock_irqsave(&gpio_lock, flags);
-	list_del(&gdev->list);
-	spin_unlock_irqrestore(&gpio_lock, flags);
 err_free_label:
 	kfree_const(gdev->label);
 err_free_descs:
-- 
2.40.1

Re: [PATCH] gpio: remove GPIO device from the list unconditionally in error path

[Bartosz Golaszewski]

On Mon, Feb 5, 2024 at 11:22 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> Since commit 48e1b4d369cf ("gpiolib: remove the GPIO device from the list
> when it's unregistered") we remove the GPIO device entry from the global
> list (used to order devices by their GPIO ranges) when unregistering the
> chip, not when releasing the device. It will not happen when the last
> reference is put anymore. This means, we need to remove it in error path
> in gpiochip_add_data_with_key() unconditionally, without checking if the
> device's .release() callback is set.
>
> Fixes: 48e1b4d369cf ("gpiolib: remove the GPIO device from the list when it's unregistered")
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> ---

Queued for fixes.

Bart