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

[Jinjie Ruan <ruanjinjie@xxxxxxxxxx>]

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.

>> Fixes: b59c122484ec ("spi: spi-geni-qcom: Add support for GPI dma")
>> Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
>> ---
>>   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);
>>   }
>>   
>