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

From: Peter Chen
Date: Sat Sep 05 2015 - 23:33:24 EST


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?

--

Best Regards,
Peter Chen
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