[PATCH 2/3] dmaengine: stm32-dmamux: fix reference leak in stm32_dmamux

From: Qinglang Miao
Date: Fri Nov 27 2020 - 04:42:44 EST


pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to putting operation will result in a
reference leak here.

A new function pm_runtime_resume_and_get is introduced in
[0] to keep usage counter balanced. So We fix the reference
leak by replacing it with new funtion.

[0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")

Fixes: f65c2e14b096 ("dmaengine: stm32-dmamux: add suspend/resume power management support")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
drivers/dma/stm32-dmamux.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c
index a10ccd964..bddd3b23f 100644
--- a/drivers/dma/stm32-dmamux.c
+++ b/drivers/dma/stm32-dmamux.c
@@ -137,7 +137,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,

/* Set dma request */
spin_lock_irqsave(&dmamux->lock, flags);
- ret = pm_runtime_get_sync(&pdev->dev);
+ ret = pm_runtime_resume_and_get(&pdev->dev);
if (ret < 0) {
spin_unlock_irqrestore(&dmamux->lock, flags);
goto error;
@@ -336,7 +336,7 @@ static int stm32_dmamux_suspend(struct device *dev)
struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev);
int i, ret;

- ret = pm_runtime_get_sync(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
return ret;

@@ -361,7 +361,7 @@ static int stm32_dmamux_resume(struct device *dev)
if (ret < 0)
return ret;

- ret = pm_runtime_get_sync(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
return ret;

--
2.23.0