From 9d7697fabbc72428f981c01ddbe0a6be0ce8b6fa Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Fri, 22 May 2026 11:12:37 +0200 Subject: [PATCH] gpio: shared: fix lockdep false positive by removing unneeded lock By the time gpio_device_teardown_shared() is called, the parent device is gone from the global list of GPIO devices and all outstanding SRCU read-side critical sections have completed. That means that no concurrent gpio_find_and_request() can call gpio_shared_add_proxy_lookup() for this device at this time. There's also no risk of the parent device being re-bound to the driver before the unbinding completes (including the child devices). Lockdep produces a false-positive report about a possible circular dependency as it doesn't know the ordering guarantee. Not taking the ref->lock in gpio_device_teardown_shared() silences it and is safe to do. Cc: stable@vger.kernel.org Fixes: ea513dd3c066 ("gpio: shared: make locking more fine-grained") Reviewed-by: Linus Walleij Link: https://patch.msgid.link/20260522-gpio-shared-deadlock-v1-2-76bca088f8c0@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-shared.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/gpio/gpiolib-shared.c b/drivers/gpio/gpiolib-shared.c index 087b64c06c9f..de72776fb154 100644 --- a/drivers/gpio/gpiolib-shared.c +++ b/drivers/gpio/gpiolib-shared.c @@ -605,8 +605,6 @@ void gpio_device_teardown_shared(struct gpio_device *gdev) gpiod_free_commit(&gdev->descs[entry->offset]); list_for_each_entry(ref, &entry->refs, list) { - guard(mutex)(&ref->lock); - if (ref->lookup) { gpiod_remove_lookup_table(ref->lookup); kfree(ref->lookup->table[0].key);