Re: [PATCH] spi: tegra20-slink: Fix runtime PM imbalance on error

From: Jon Hunter
Date: Thu May 21 2020 - 04:46:55 EST



On 21/05/2020 09:38, Jon Hunter wrote:
>
> On 21/05/2020 09:04, Andy Shevchenko wrote:
>> On Thu, May 21, 2020 at 10:50 AM Dinghao Liu <dinghao.liu@xxxxxxxxxx> wrote:
>>>
>>> pm_runtime_get_sync() increments the runtime PM usage counter even
>>> when it returns an error code. Thus a pairing decrement is needed on
>>> the error handling path to keep the counter balanced.
>>
>> ...
>>
>>> ret = pm_runtime_get_sync(&pdev->dev);
>>> if (ret < 0) {
>>> dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
>>
>>> + pm_runtime_put(&pdev->dev);
>>
>> For all your patches, please, double check what you are proposing.
>>
>> Here, I believe, the correct one will be _put_noidle().
>>
>> AFAIU you are not supposed to actually suspend the device in case of error.
>> But I might be mistaken, thus see above.
>>
>>> goto exit_pm_disable;
>>> }
>
>
> Is there any reason why this is not handled in pm_runtime_get itself?

Ah I see a response from Rafael here:
https://lkml.org/lkml/2020/5/20/1100

OK so this is intentional and needs to be fixed.

Jon

--
nvpublic