On 31-05-21, 14:11, yukuai (C) wrote:

On 2021/05/31 12:00, Vinod Koul wrote:

quoted

On 17-05-21, 16:18, Yu Kuai wrote:

quoted

pm_runtime_get_sync will increment pm usage counter even it failed.
Forgetting to putting operation will result in reference leak here.
Fix it by replacing it with pm_runtime_resume_and_get to keep usage
counter balanced.

Reported-by: Hulk Robot <redacted>
Signed-off-by: Yu Kuai <redacted>
---
  drivers/dma/sh/usb-dmac.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
index 8f7ceb698226..2a6c8fd8854e 100644
--- a/drivers/dma/sh/usb-dmac.c
+++ b/drivers/dma/sh/usb-dmac.c

@@ -796,7 +796,7 @@ static int usb_dmac_probe(struct platform_device *pdev)
  	/* Enable runtime PM and initialize the device. */
  	pm_runtime_enable(&pdev->dev);
-	ret = pm_runtime_get_sync(&pdev->dev);
+	ret = pm_runtime_resume_and_get(&pdev->dev);

This does not seem to fix anything.. the below goto goes and disables
the runtime_pm for this device and thus there wont be any leak

Hi,

If pm_runtime_get_sync() fails and increments the pm.usage_count
variable, pm_runtime_disable() does not reset the counter, and
we still need to decrement the usage count when pm_runtime_get_sync()
fails. Do I miss anthing?

Yes the rumtime_pm is disabled on failure here and the count would have
no consequence...

-- 
~Vinod

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