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| author | Hans de Goede <hdegoede@redhat.com> | 2024-04-02 18:43:45 +0200 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-04-03 13:04:32 +0200 |
| commit | e8acd2d209a387f2358c2c83fe894b444db9ea46 (patch) | |
| tree | ed3c86a358676116957e99a6c8d96772a64f9ddc /drivers/gpio | |
| parent | Linux 6.9-rc2 (diff) | |
| download | linux-e8acd2d209a387f2358c2c83fe894b444db9ea46.tar.xz linux-e8acd2d209a387f2358c2c83fe894b444db9ea46.zip | |
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 <brgl@bgdev.pl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
[Bartosz: fix a typo in commit message]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 3 |
1 files changed, 3 insertions, 0 deletions
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); |