Re: [PATCH 2/3] dmaengine: usb-dmac: Fix PM reference leak in usb_dmac_probe()
From: yukuai (C) <hidden>
Date: 2021-05-31 06:11:38
Also in:
linux-arm-kernel, lkml
On 2021/05/31 12:00, Vinod Koul wrote:
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? Thansk! Yu Kuai
quoted
if (ret < 0) { dev_err(&pdev->dev, "runtime PM get sync failed (%d)\n", ret); goto error_pm; -- 2.25.4