Re: [PATCH v3 01/24] gpio: protect the list of GPIO devices with SRCU

From: Hillf Danton
Date: Sat Feb 10 2024 - 06:01:09 EST


On Thu, 8 Feb 2024 10:58:57 +0100 Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> @@ -382,11 +389,13 @@ static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev)
> /* add between prev and next */
> if (prev->base + prev->ngpio <= gdev->base
> && gdev->base + gdev->ngpio <= next->base) {
> - list_add(&gdev->list, &prev->list);
> + list_add_rcu(&gdev->list, &prev->list);
> return 0;
> }
> }
>
> + synchronize_srcu(&gpio_devices_srcu);
> +
If not typo, could you shed light on why this sync is needed?

> return -EBUSY;
> }