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From: Tzung-Bi Shih <tzungbi@kernel.org>
To: Bartosz Golaszewski <brgl@kernel.org>, Linus Walleij <linusw@kernel.org>
Cc: tzungbi@kernel.org, linux-gpio@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Marek Szyprowski <m.szyprowski@samsung.com>
Subject: [PATCH] gpio: Fix lockdep warnings in gpiolib_{cdev,sysfs}_register()
Date: Sat, 28 Feb 2026 21:14:30 +0800	[thread overview]
Message-ID: <20260228131430.102388-1-tzungbi@kernel.org> (raw)

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: Marek Szyprowski <m.szyprowski@samsung.com>
Closes: https://lore.kernel.org/all/506ce9b3-d492-4fce-9d02-330e411911e2@samsung.com/
Fixes: cf674f1a0c98 ("gpio: Ensure struct gpio_chip for gpiochip_setup_dev()")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
 drivers/gpio/gpiolib-cdev.c  | 2 --
 drivers/gpio/gpiolib-sysfs.c | 2 --
 2 files changed, 4 deletions(-)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index 7ebdb4993a74..f36b7c06996d 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -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);
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 748a3eb1bf35..fc06b0c2881b 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -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
-- 
2.51.0


             reply	other threads:[~2026-02-28 13:14 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CGME20260228131459eucas1p1b5deb465c52d0990a6920b0d8981975f@eucas1p1.samsung.com>
2026-02-28 13:14 ` Tzung-Bi Shih [this message]
2026-03-02  8:42   ` Bartosz Golaszewski
2026-03-02  9:08   ` Marek Szyprowski
2026-03-02  9:11   ` Bartosz Golaszewski

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