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

Qinglang Miao miaoqinglang at huawei.com
Fri Nov 27 04:45:24 EST 2020


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 at huawei.com>
Signed-off-by: Qinglang Miao <miaoqinglang at huawei.com>
---
 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




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