[PATCH 1/3] dmaengine: stm32-dma: fix reference leak in stm32_dma

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: 05f8740a0e6f ("dmaengine: stm32-dma: add suspend/resume power management support")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
drivers/dma/stm32-dma.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index d0055d2f0..1150aa90e 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -1187,7 +1187,7 @@ static int stm32_dma_alloc_chan_resources(struct dma_chan *c)

chan->config_init = false;

- ret = pm_runtime_get_sync(dmadev->ddev.dev);
+ ret = pm_runtime_resume_and_get(dmadev->ddev.dev);
if (ret < 0)
return ret;

@@ -1455,7 +1455,7 @@ static int stm32_dma_suspend(struct device *dev)
struct stm32_dma_device *dmadev = dev_get_drvdata(dev);
int id, ret, scr;

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

--
2.23.0