Re: [RFC PATCH 2/3] usbnet: Avoid potential races in usbnet_deferred_kevent()

From: Oliver Neukum
Date: Wed Sep 20 2017 - 04:27:03 EST


Am Dienstag, den 19.09.2017, 13:51 -0700 schrieb Guenter Roeck:
> On Tue, Sep 19, 2017 at 1:37 PM, Oliver Neukum <oneukum@xxxxxxxx> wrote:
> >
> > Am Dienstag, den 19.09.2017, 09:15 -0700 schrieb Douglas Anderson:
> > >
[..]
> > > NOTES:
> > > - No known bugs are fixed by this; it's just found by code inspection.
> >
> > Hi,
> >
> > unfortunately the patch is wrong. The flags must be cleared only
> > in case the handler is successful. That is not guaranteed.
> >
>
> Just out of curiosity, what is the retry mechanism ? Whenever a new,
> possibly unrelated, event is scheduled ?

Hi,

that actually depends on the flag.
Look at the case of fail_lowmem. There we reschedule.

HTH
Oliver