Re: [PATCH v2 1/2] spi: geni-qcom: Fix incorrect free_irq() sequence

[Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com>]

Thanks !

On 9/6/2024 12:17 PM, Jinjie Ruan wrote:
> 
> 
> On 2024/9/6 12:27, Mukesh Kumar Savaliya wrote:
>> Hi Jinjie,
>>
>> On 9/6/2024 8:43 AM, Jinjie Ruan wrote:
>>> In spi_geni_remove(), the IRQ will still remain and it's interrupt
>>> handler
>>> may use the dma channel after release dma channel and before free irq,
>>> which is not secure, fix it.
>>>
>> What's the possibility of having irq if spi_geni_release_dma_chan(mas)
>> is completed ? As such controller is already unregistered so transfer
>> request can't come.
> 
> The irq is not freed, the IRQ can come and then it may enter the irq
> handler with the registered one.
> 
My question is about knowing source of interrupt at earlier place.
By just moving it above to spi_geni_release_dma_chan(), is there 
anything changing ?

>>> Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
>>> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
>>> ---
>>>    drivers/spi/spi-geni-qcom.c | 3 ++-
>>>    1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
>>> index 37ef8c40b276..fc2819effe2d 100644
>>> --- a/drivers/spi/spi-geni-qcom.c
>>> +++ b/drivers/spi/spi-geni-qcom.c
>>> @@ -1170,9 +1170,10 @@ static void spi_geni_remove(struct
>>> platform_device *pdev)
>>>        /* Unregister _before_ disabling pm_runtime() so we stop
>>> transfers */
>>>        spi_unregister_controller(spi);
>>>    +    free_irq(mas->irq, spi);
>>> +
>>>        spi_geni_release_dma_chan(mas);
>>>    -    free_irq(mas->irq, spi);
>>>        pm_runtime_disable(&pdev->dev);
>>>    }
>>>    
>>