We will eventually switch to protecting the GPIO descriptors with a mutex
but until then, we need to allocate memory for the label copy atomically
while we're holding the global spinlock.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-gpio/
62588146-eed6-42f7-ba26-
160226b109fe@moroto.mountain/T/#u
Fixes:
f8d05e276b45 ("gpiolib: remove gpiochip_is_requested()")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
if (!test_bit(FLAG_REQUESTED, &desc->flags))
return NULL;
- label = kstrdup(desc->label, GFP_KERNEL);
+ /*
+ * FIXME: Once we mark gpiod_direction_input/output() and
+ * gpiod_get_direction() with might_sleep(), we'll be able to protect
+ * the GPIO descriptors with mutex (while value setting operations will
+ * become lockless).
+ *
+ * Until this happens, this allocation needs to be atomic.
+ */
+ label = kstrdup(desc->label, GFP_ATOMIC);
if (!label)
return ERR_PTR(-ENOMEM);