Commit fdfe3e72 authored by Tzung-Bi Shih's avatar Tzung-Bi Shih Committed by Bartosz Golaszewski
Browse files

gpio: Fix lockdep warnings in gpiolib_{cdev,sysfs}_register() 



A lockdep warning is reported in gpiolib-cdev driver:

  WARNING: drivers/gpio/gpiolib-cdev.c:2735 at
  gpiolib_cdev_register+0x114/0x140, CPU#1: swapper/0/1
  Modules linked in:
  CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted
  7.0.0-rc1-next-20260227-00065-g6af4b9cfeded #12259 PREEMPT
  Hardware name: Samsung Exynos (Flattened Device Tree)
  Call trace:
    unwind_backtrace from show_stack+0x10/0x14
    show_stack from dump_stack_lvl+0x68/0x88
    dump_stack_lvl from __warn+0x94/0x210
    __warn from warn_slowpath_fmt+0x1b0/0x1bc
    warn_slowpath_fmt from gpiolib_cdev_register+0x114/0x140
    gpiolib_cdev_register from gpiochip_setup_dev+0x4c/0xd0
    gpiochip_setup_dev from gpiochip_add_data_with_key+0x960/0xad4
    gpiochip_add_data_with_key from devm_gpiochip_add_data_with_key+0x20/0x5c

This is because the SRCU wasn't held in gpiolib_cdev_register() when the
caller is from gpiochip_add_data_with_key() instead of
gpiochip_setup_devs().  gpiochip_sysfs_register() shares the similar
concern.

Given that both gpiolib_cdev_register() and gpiochip_sysfs_register()
are only called from gpiolib but no external users.  Remove the lockdep
checks to fix the warnings.

Reported-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Closes: https://lore.kernel.org/all/506ce9b3-d492-4fce-9d02-330e411911e2@samsung.com/


Fixes: cf674f1a ("gpio: Ensure struct gpio_chip for gpiochip_setup_dev()")
Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
Tested-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Link: https://patch.msgid.link/20260228131430.102388-1-tzungbi@kernel.org


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
parent c7f92042

drivers/gpio/gpiolib-cdev.c

+0 −2
Original line number Diff line number Diff line
@@ -2732,8 +2732,6 @@ int gpiolib_cdev_register(struct gpio_chip *gc, dev_t devt) 
	struct gpio_device *gdev = gc->gpiodev;

	int ret;



	lockdep_assert_held(&gdev->srcu);



	cdev_init(&gdev->chrdev, &gpio_fileops);

	gdev->chrdev.owner = THIS_MODULE;

	gdev->dev.devt = MKDEV(MAJOR(devt), gdev->id);

drivers/gpio/gpiolib-sysfs.c

+0 −2
Original line number Diff line number Diff line
@@ -990,8 +990,6 @@ int gpiochip_sysfs_register(struct gpio_chip *gc) 
	struct device *parent;

	int err;



	lockdep_assert_held(&gdev->srcu);



	/*

	 * Many systems add gpio chips for SOC support very early,

	 * before driver model support is available.  In those cases we