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From: Tzung-Bi Shih <tzungbi@kernel.org>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Danilo Krummrich <dakr@kernel.org>,
	Bartosz Golaszewski <brgl@bgdev.pl>,
	Linus Walleij <linusw@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>, Shuah Khan <shuah@kernel.org>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>,
	Jason Gunthorpe <jgg@nvidia.com>, Johan Hovold <johan@kernel.org>,
	linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
	chrome-platform@lists.linux.dev, tzungbi@kernel.org,
	Dan Williams <dan.j.williams@intel.com>,
	linux-gpio@vger.kernel.org
Subject: [PATCH v2 03/11] gpio: sysfs: Remove redundant check for struct gpio_chip
Date: Tue,  3 Feb 2026 06:10:50 +0000	[thread overview]
Message-ID: <20260203061059.975605-4-tzungbi@kernel.org> (raw)
In-Reply-To: <20260203061059.975605-1-tzungbi@kernel.org>

gpiochip_sysfs_unregister() is only called by gpiochip_remove() where
the struct gpio_chip is ensured.

Remove the redundant check.

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
v2:
- No changes.

v1: https://lore.kernel.org/all/20260116081036.352286-9-tzungbi@kernel.org

 drivers/gpio/gpiolib-sysfs.c | 9 +--------
 drivers/gpio/gpiolib-sysfs.h | 6 ++++--
 drivers/gpio/gpiolib.c       | 2 +-
 3 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index cd553acf3055..8e6b09d8b559 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -1048,11 +1048,10 @@ int gpiochip_sysfs_register(struct gpio_device *gdev)
 	return 0;
 }
 
-void gpiochip_sysfs_unregister(struct gpio_device *gdev)
+void gpiochip_sysfs_unregister(struct gpio_device *gdev, struct gpio_chip *chip)
 {
 	struct gpiodev_data *data;
 	struct gpio_desc *desc;
-	struct gpio_chip *chip;
 
 	scoped_guard(mutex, &sysfs_lock) {
 		data = gdev_get_data(gdev);
@@ -1066,12 +1065,6 @@ void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 		kfree(data);
 	}
 
-	guard(srcu)(&gdev->srcu);
-
-	chip = srcu_dereference(gdev->chip, &gdev->srcu);
-	if (!chip)
-		return;
-
 	/* unregister gpiod class devices owned by sysfs */
 	for_each_gpio_desc_with_flag(chip, desc, GPIOD_FLAG_SYSFS) {
 		gpiod_unexport(desc);
diff --git a/drivers/gpio/gpiolib-sysfs.h b/drivers/gpio/gpiolib-sysfs.h
index b794b396d6a5..93debe8e118c 100644
--- a/drivers/gpio/gpiolib-sysfs.h
+++ b/drivers/gpio/gpiolib-sysfs.h
@@ -8,7 +8,8 @@ struct gpio_device;
 #ifdef CONFIG_GPIO_SYSFS
 
 int gpiochip_sysfs_register(struct gpio_device *gdev);
-void gpiochip_sysfs_unregister(struct gpio_device *gdev);
+void gpiochip_sysfs_unregister(struct gpio_device *gdev,
+			       struct gpio_chip *chip);
 
 #else
 
@@ -17,7 +18,8 @@ static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
 	return 0;
 }
 
-static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
+static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev,
+					     struct gpio_chip *chip)
 {
 }
 
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index a6dd07be126c..3137e6f1108a 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1281,7 +1281,7 @@ void gpiochip_remove(struct gpio_chip *gc)
 	struct gpio_device *gdev = gc->gpiodev;
 
 	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
-	gpiochip_sysfs_unregister(gdev);
+	gpiochip_sysfs_unregister(gdev, gc);
 	gpiochip_free_hogs(gc);
 	gpiochip_free_remaining_irqs(gc);
 
-- 
2.53.0.rc2.204.g2597b5adb4-goog


  parent reply	other threads:[~2026-02-03  6:11 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-03  6:10 [PATCH v2 00/11] gpio: Adopt revocable mechanism for UAF prevention Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 01/11] gpio: Access `gpio_bus_type` in gpiochip_setup_dev() Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 02/11] gpio: Remove redundant check for struct gpio_chip Tzung-Bi Shih
2026-02-03  6:10 ` Tzung-Bi Shih [this message]
2026-02-04 10:33   ` [PATCH v2 03/11] gpio: sysfs: " Bartosz Golaszewski
2026-02-05  8:51     ` Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 04/11] gpio: Ensure struct gpio_chip for gpiochip_setup_dev() Tzung-Bi Shih
2026-02-04 10:36   ` Bartosz Golaszewski
2026-02-05  8:51     ` Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 05/11] gpio: cdev: Don't check struct gpio_chip in gpio_chrdev_open() Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 06/11] selftests: gpio: Add gpio-cdev-uaf tests Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 07/11] gpio: Add revocable provider handle for struct gpio_chip Tzung-Bi Shih
2026-02-04 12:58   ` Bartosz Golaszewski
2026-02-05  8:52     ` Tzung-Bi Shih
2026-02-05 16:57       ` Bartosz Golaszewski
2026-02-06  9:13         ` Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 08/11] gpio: cdev: Leverage revocable for accessing " Tzung-Bi Shih
2026-02-03  9:51   ` Tzung-Bi Shih
2026-02-04 13:02   ` Bartosz Golaszewski
2026-02-03  6:10 ` [PATCH v2 09/11] gpio: Remove gpio_chip_guard by using revocable Tzung-Bi Shih
2026-02-04 13:05   ` Bartosz Golaszewski
2026-02-03  6:10 ` [PATCH v2 10/11] gpio: Leverage revocable for accessing struct gpio_chip Tzung-Bi Shih
2026-02-03  6:10 ` [PATCH v2 11/11] gpio: Remove unused `chip` and `srcu` in struct gpio_device Tzung-Bi Shih
2026-02-03 11:15 ` [PATCH v2 00/11] gpio: Adopt revocable mechanism for UAF prevention Bartosz Golaszewski
2026-02-03 16:53 ` Bartosz Golaszewski

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