Re: [PATCH] of/irq: Don't ignore interrupt-controller when interrupt-map failed

From: Rob Herring
Date: Fri Nov 12 2021 - 10:56:00 EST


On Fri, Nov 12, 2021 at 9:28 AM Marc Zyngier <maz@xxxxxxxxxx> wrote:
>
> On Fri, 12 Nov 2021 15:04:15 +0000,
> Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> >
> > On Fri, Nov 12, 2021 at 02:36:44PM +0000, Marc Zyngier wrote:
> > > Since 041284181226 ("of/irq: Allow matching of an interrupt-map local
> > > to an interrupt controller"), the irq code favors using an interrupt-map
> > > over a interrupt-controller property if both are available, while the
> > > earlier behaviour was to ignore the interrupt-map altogether.
> > >
> > > However, we now end-up with the opposite behaviour, which is to
> > > ignore the interrupt-controller property even if the interrupt-map
> > > fails to match its input. This new behaviour breaks the AmigaOne
> > > X1000 machine, which ships with an extremely "creative" (read:
> > > broken) device tree.
> > >
> > > Fix this by allowing the interrupt-controller property to be selected
> > > when interrupt-map fails to match anything.
> > >
> > > Fixes: 041284181226 ("of/irq: Allow matching of an interrupt-map local to an interrupt controller")
> > > Reported-by: Christian Zigotzky <chzigotzky@xxxxxxxxxxx>
> > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
> > > Link: https://lore.kernel.org/r/78308692-02e6-9544-4035-3171a8e1e6d4@xxxxxxxxxxx
> > > Cc: Rob Herring <robh@xxxxxxxxxx>
> > > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> >
> > I'm not qualified to review this, but since 041284181226 was merged
> > via my tree along with the rest of the Apple stuff, let me know if
> > you'd like me to merge this.
> >
> > I see Rob has a comment, so if you want to take care merging it
> > yourself, that's certainly fine with me.
>
> I have a couple of IRQ patches that need to go in, so happy to route
> it via the irqchip tree if Rob gives his blessing.

I have stuff for rc1 too, but feel free to take it:

With the WARN added,

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>