Re: [PATCHv2] musb_host: fix lockup on rxcsr_h_error

[Sergei Shtylyov]

Hello.

On 5/4/2016 10:17 PM, Bin Liu wrote:

> > > > > > > > > > yes, it also works with that reset and go to finish:
> > > > > > > > > >
> > > > > > > > > > diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
> > > > > > > > > > index c3d5fc9..8cd98e7 100644
> > > > > > > > > > --- a/drivers/usb/musb/musb_host.c
> > > > > > > > > > +++ b/drivers/usb/musb/musb_host.c
> > > > > > > > > > @@ -1599,6 +1599,10 @@ void musb_host_rx(struct musb *musb, u8 epnum)
> > > > > > > > > >                 status = -EPROTO;
> > > > > > > > > >                 musb_writeb(epio, MUSB_RXINTERVAL, 0);
> > > > > > > > > >
> > > > > > > > > > +               rx_csr &= ~MUSB_RXCSR_H_ERROR;
> > > > > > > > > > +               musb_writew(epio, MUSB_RXCSR, rx_csr);
> > > > > > > > > > +
> > > > > > > > > > +               goto finish;
> > > > > > > > > >         } else if (rx_csr & MUSB_RXCSR_DATAERROR) {
> > > > > > > > > >
> > > > > > > > > >                 if (USB_ENDPOINT_XFER_ISOC != qh->type) {
> > > > > > > > >
> > > > > > > > > Thanks for testing it.
> > > > > > > >
> > > > > > > > Have tested your patch and now both FT4232 and Huawei don't freeze on removal.
> > > > > > > >
> > > > > > > > Bin, Max thanks for fixing this issue.
> > > > > > > >
> > > > > > > > Tested-by: Yegor Yefremov <yegorslists@xxxxxxxxxxxxxx>
> > > > > > >
> > > > > > > Thanks for testing.
> > > > > > >
> > > > > > > Can you please test the patch [1] instead? I'd like to use it as the
> > > > > > > fix.
> > > > > > >
> > > > > > > [1] http://marc.info/?l=linux-usb&m=146222355213935&w=2
> > > > > >
> > > > > > The patch behaves the same as the previous one.
> > > > > >
> > > > > > Kernel: 4.6-rc6
> > > > >
> > > > > Thanks for testing. I will add your Tested-by.
> > > >
> > > > If you'll resend this patch, it would be good to add it to stable
> > > > kernels. I've tested 3.18.32 and it fixes the error too.
> >
> > > Thanks for testing.
> > >
> > > My plan is to not rush it into stable, but let it sit in v4.7 for a
> > > while first.
> >
> >    Are you serious? Fixing interrupt storm due to not cleared
> > interrupt bit will only be done in 4.7?
>
> Well, I am new to maintianer's role, and thought there is only one week
> away to v4.7 merge window, there is no big difference to let this patch
> get into v4.7-rc1. If getting the fix into upstream as soon as possible
> is important, I will send it for 4.6-rc7.
>
> BTY, the issue is not because of not clearing interrupt bit, but the hub
> has no chance to report the disconnect event, which causes the
> controller keeps generating the interrupt for every new rx urb.

   Sorry, looking at the Mentor manuals, I got the impression that whenever 
the RXCSR.Error is set, there's interrupt. Probably they meant that the 
interrupt is generated only on transition from 0 to 1....

> Regards,
> -Bin.

MBR, Sergei