Re: [PATCH net-next 2/2] enetc: use napi_schedule to be compatible with PREEMPT_RT

From: Vladimir Oltean
Date: Wed Aug 12 2020 - 10:34:37 EST


On Wed, Aug 12, 2020 at 03:51:44PM +0200, Sebastian Andrzej Siewior wrote:
> On 2020-08-03 18:21:45 [-0700], David Miller wrote:
> > From: Vladimir Oltean <olteanv@xxxxxxxxx>
> > > The driver calls napi_schedule_irqoff() from a context where, in RT,
> > > hardirqs are not disabled, since the IRQ handler is force-threaded.
>
> > >
> > > Signed-off-by: Jiafei Pan <Jiafei.Pan@xxxxxxx>
> > > Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> >
> > Applied.
>
> Could these two patches be forwarded -stable, please? The changelog
> describes this as a problem on PREEMPT_RT but this also happens on !RT
> with the `threadirqs' commandline switch.
>
> Sebastian

I expect the driver maintainers to have something to say about this. I
didn't test on stable kernels, and at least for dpaa2-eth, the change
would need to go pretty deep down the stable line.

Also, not really sure who is using the threadirqs option except for
testing purposes.

Thanks,
-Vladimir