From e8acd2d209a387f2358c2c83fe894b444db9ea46 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 2 Apr 2024 18:43:45 +0200 Subject: [PATCH] gpiolib: Fix triggering "kobject: 'gpiochipX' is not initialized, yet" kobject_get() errors When a gpiochip gets added by loading a module, then another driver may be waiting for that gpiochip to load on the deferred-probe list. If the deferred-probe for the consumer of gpiochip then triggers between the gpiodev_add_to_list_unlocked() calls which makes gpio_device_find() see the chip and the gpiochip_setup_dev() later then gpio_device_find() does a kobject_get() on an uninitialized kobject since the kobject is initialized by gpiochip_setup_dev() calling device_initialize(): arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring ------------[ cut here ]------------ kobject: 'gpiochip5' (00000000241466f2): is not initialized, yet kobject_get() is being called. WARNING: CPU: 3 PID: 42 at lib/kobject.c:640 kobject_get+0x43/0x70 Call Trace: kobject_get gpio_device_find gpiod_find_and_request gpiod_get snd_byt_wm5102_mc_probe Not only is the device not initialized yet, but when the gpio-device is added to the list things like the irqchip also have not been initialized yet. So gpio_device_find() should really ignore the gpio-device until gpiochip_add_data_with_key() is fully done. Add a device_is_registered() check to gpio_device_find() to ignore gpio-devices on the list which are not yet fully initialized. Fixes: aab5c6f20023 ("gpio: set device type for GPIO chips") Suggested-by: Bartosz Golaszewski Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko [Bartosz: fix a typo in commit message] Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 59ccf9a3e153..94903fc1c145 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1175,6 +1175,9 @@ struct gpio_device *gpio_device_find(const void *data, list_for_each_entry_srcu(gdev, &gpio_devices, list, srcu_read_lock_held(&gpio_devices_srcu)) { + if (!device_is_registered(&gdev->dev)) + continue; + guard(srcu)(&gdev->srcu); gc = srcu_dereference(gdev->chip, &gdev->srcu);