Re: [PATCH v4 5/9] usb: dwc3: core: make dual-role work with OTG irq

Roger Quadros
2015-09-15T14:46:44Z

On 06/09/15 05:20, Peter Chen wrote:
> On Wed, Sep 02, 2015 at 09:43:38AM -0500, Felipe Balbi wrote:
>> Hi,
>>
>>> +
>>> +static irqreturn_t dwc3_otg_irq(int irq, void *_dwc)
>>> +{
>>> + struct dwc3 *dwc = _dwc;
>>> + irqreturn_t ret = IRQ_NONE;
>>> + u32 reg;
>>> +
>>> + spin_lock(&dwc->lock);
>>
>> this seems unnecessary, we're already in hardirq with IRQs disabled.
>> What sort of race could we have ? (in fact, this also needs change in
>> dwc3/gadget.c).
>>
>
> Is it possible the kernel process is accessing the content you will
> access?
>
When kernel process accesses the data we'll never reach here
as we're protecting it with spinlock_irqsave(), spinunlock_irqrestore().

cheers,
-roger