[PATCH 2/3] dmaengine: usb-dmac: Fix PM reference leak in usb_dmac_probe()

yukuai (C) yukuai3 at huawei.com
Mon Jul 5 01:41:39 PDT 2021


Hi, Vinod

Are you still intrested in accepting this patch?

Thanks,
Yu Kuai

On 2021/06/07 18:19, Vinod Koul wrote:
> On 07-06-21, 10:06, Johan Hovold wrote:
>> On Thu, Jun 03, 2021 at 04:39:08PM +0530, Vinod Koul wrote:
>>> On 31-05-21, 11:19, Johan Hovold wrote:
>>>> On Mon, May 31, 2021 at 02:27:34PM +0530, Vinod Koul wrote:
>>>>> On 31-05-21, 14:11, yukuai (C) wrote:
>>>>>> On 2021/05/31 12:00, Vinod Koul wrote:
>>>>>>> On 17-05-21, 16:18, Yu Kuai wrote:
>>>>>>>> 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.
>>
>>>>> Yes the rumtime_pm is disabled on failure here and the count would have
>>>>> no consequence...
>>>>
>>>> You should still balance the PM usage counter as it isn't reset for
>>>> example when reloading the driver.
>>>
>>> Should I driver trust that on load PM usage counter is balanced and not
>>> to be reset..?
>>
>> Not sure what you're asking here. But a driver should never leave the PM
>> usage counter unbalanced.
> 
> Thinking about again, yes we should safely assume the counter is
> balanced when driver loads.. so unloading while balancing sounds better
> behaviour
> 
> Thanks
> 



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