This is a note to let you know that I've just added the patch titled
gpio: sysfs: extend the critical section for unregistering sysfs devices
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gpio-sysfs-extend-the-critical-section-for-unregiste.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d4cab131ac1267e6d27989d392dac5fbf8ed8404
Author: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
Date: Wed Jan 24 14:08:45 2024 +0100
gpio: sysfs: extend the critical section for unregistering sysfs devices
[ Upstream commit 59cba4a0e6ca1058fbf88fec22530a4e2841802a ]
Checking the gdev->mockdev pointer for NULL must be part of the critical
section.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 12d853845bb80..6c27312c62788 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
+#include <linux/cleanup.h>
#include <linux/device.h>
#include <linux/idr.h>
#include <linux/init.h>
@@ -774,15 +775,15 @@ void gpiochip_sysfs_unregister(struct gpio_device *gdev)
struct gpio_desc *desc;
struct gpio_chip *chip = gdev->chip;
- if (!gdev->mockdev)
- return;
+ scoped_guard(mutex, &sysfs_lock) {
+ if (!gdev->mockdev)
+ return;
- device_unregister(gdev->mockdev);
+ device_unregister(gdev->mockdev);
- /* prevent further gpiod exports */
- mutex_lock(&sysfs_lock);
- gdev->mockdev = NULL;
- mutex_unlock(&sysfs_lock);
+ /* prevent further gpiod exports */
+ gdev->mockdev = NULL;
+ }
/* unregister gpiod class devices owned by sysfs */
for_each_gpio_desc_with_flag(chip, desc, FLAG_SYSFS) {
