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* [PATCH] gpio: xilinx: fix runtime PM leak on request error path
@ 2026-09-23 11:39 Ridham Khurana
  2026-09-28  8:29 ` Bartosz Golaszewski
  0 siblings, 1 reply; 2+ messages in thread
From: Ridham Khurana @ 2026-09-23 11:39 UTC (permalink / raw)
  To: Shubhrajyoti Datta, Linus Walleij, Bartosz Golaszewski
  Cc: Srinivas Neeli, Michal Simek, linux-gpio, linux-arm-kernel,
	linux-kernel, Shuah Khan, Jori Koolstra, Brigham Campbell,
	linux-kernel-mentees, Ridham Khurana, stable

pm_runtime_get_sync() leaves the usage counter incremented even when it
fails, and xgpio_request() returns the error without dropping it.

gpiolib does not call ->free() when ->request() fails, so xgpio_free(),
which holds the only matching pm_runtime_put(), never runs. The reference
is leaked and the controller can no longer runtime-suspend, so its clock
stays enabled.

Switch to pm_runtime_resume_and_get(), which only increments the usage
counter on success.

Fixes: 26b04774621e ("gpio: gpio-xilinx: Add support for suspend and resume")
Cc: stable@vger.kernel.org
Signed-off-by: Ridham Khurana <khurana.ridham222@gmail.com>
---
Build-tested on arm64 with CONFIG_GPIO_XILINX=m. Not tested on hardware.
 drivers/gpio/gpio-xilinx.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index 532205175827..9406ce85f933 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -271,14 +271,7 @@ static void xgpio_save_regs(struct xgpio_instance *chip)
 
 static int xgpio_request(struct gpio_chip *chip, unsigned int offset)
 {
-	int ret;
-
-	ret = pm_runtime_get_sync(chip->parent);
-	/*
-	 * If the device is already active pm_runtime_get() will return 1 on
-	 * success, but gpio_request still needs to return 0.
-	 */
-	return ret < 0 ? ret : 0;
+	return pm_runtime_resume_and_get(chip->parent);
 }
 
 static void xgpio_free(struct gpio_chip *chip, unsigned int offset)
-- 
2.47.3



^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] gpio: xilinx: fix runtime PM leak on request error path
  2026-09-23 11:39 [PATCH] gpio: xilinx: fix runtime PM leak on request error path Ridham Khurana
@ 2026-09-28  8:29 ` Bartosz Golaszewski
  0 siblings, 0 replies; 2+ messages in thread
From: Bartosz Golaszewski @ 2026-09-28  8:29 UTC (permalink / raw)
  To: Shubhrajyoti Datta, Linus Walleij, Bartosz Golaszewski,
	Ridham Khurana
  Cc: Bartosz Golaszewski, Srinivas Neeli, Michal Simek, linux-gpio,
	linux-arm-kernel, linux-kernel, Shuah Khan, Jori Koolstra,
	Brigham Campbell, linux-kernel-mentees, stable


On Wed, 23 Sep 2026 11:39:02 +0000, Ridham Khurana wrote:
> pm_runtime_get_sync() leaves the usage counter incremented even when it
> fails, and xgpio_request() returns the error without dropping it.
> 
> gpiolib does not call ->free() when ->request() fails, so xgpio_free(),
> which holds the only matching pm_runtime_put(), never runs. The reference
> is leaked and the controller can no longer runtime-suspend, so its clock
> stays enabled.
> 
> [...]

Applied, thanks!

[1/1] gpio: xilinx: fix runtime PM leak on request error path
      https://git.kernel.org/brgl/c/ff82fc3a4a1d417dee1229681cc5285986edb1fa

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>


^ permalink raw reply	[flat|nested] 2+ messages in thread

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