Re: [irqchip: irq/irqchip-next] irqchip/bcm2836: Fix IPI acknowledgement after conversion to handle_percpu_devid_irq

[Marc Zyngier]

On 2020-12-18 20:36, Valentin Schneider wrote:
> On 18/12/20 18:40, irqchip-bot for Marc Zyngier wrote:
> > The following commit has been merged into the irq/irqchip-next branch 
> > of irqchip:
> >
> > Commit-ID:     d7f39c40ebb6986e7371510d1c20a4efee4a7f0d
> > Gitweb:        
> > https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms/d7f39c40ebb6986e7371510d1c20a4efee4a7f0d
> > Author:        Marc Zyngier <maz@xxxxxxxxxx>
> > AuthorDate:    Fri, 18 Dec 2020 18:03:46
> > Committer:     Marc Zyngier <maz@xxxxxxxxxx>
> > CommitterDate: Fri, 18 Dec 2020 18:34:17
> >
> > irqchip/bcm2836: Fix IPI acknowledgement after conversion to 
> > handle_percpu_devid_irq
> >
> > It appears that despite its name, the bcm2836_arm_irqchip_ipi_eoi()
> > callback is an acknowledgement, and not an EOI. This means that
> > we lose IPIs that are made pending between the handling of the
> > IPI and the write to LOCAL_MAILBOX0_CLR0. With the right timing,
> > things fail nicely.
> >
> > This used to work with handle_percpu_devid_fasteoi_ipi(), which
> > started by eoi-ing the interrupt. With the standard fasteoi flow,
> > this doesn't work anymore.
> >
> > So let's use this callback for what it is, an ack. Your favourite
> > RPi-2/3 is back up and running.
>
> Thanks for cleaning up my mess!

Shared responsibilities... ;-)

        M.
--
Jazz is not dead. It just smells funny...