Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang

From: Oliver Neukum
Date: Wed Feb 03 2010 - 17:58:17 EST


Am Mittwoch, 3. Februar 2010 23:37:37 schrieb Matthew Garrett:
> On Wed, Feb 03, 2010 at 06:21:39PM +0100, Oliver Neukum wrote:
> > Am Mittwoch, 3. Februar 2010 17:46:59 schrieb Matthew Garrett:
> > > > If the FIFO is full we can do nothing. Please try the attached patch.
> > >
> > > Doesn't help, I'm afraid. Does anyone have any idea why the change to
> > > use kfifo would cause this?
> >
> > The logic seems sound. That is unless the kfifo code is acting up.
> > Could you printk the value kfifo_len returns in usb_serial_generic_write_start()?
>
> kfifo_len is 4096 when it gets into the fifo_full situation.

Then this won't explain it either. Do you get to the line:
dbg("%s - starting IO", __func__);
before it hangs?

Regards
Oliver
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