Re: About Arm guests accessing to GICD_ICPENR

[Julien Grall <julien@xxxxxxx>]

On 07/09/2021 09:05, Hongda Deng wrote:
> Hi Julien,
Hi,

(+ Stefano)

> > On 06/09/2021 10:04, Hongda Deng wrote:
> > > Hi Julien,
> > > If Xen wants a complete GICD ICPENDRn emulation to fix it, do you have any
> > > suggestions.
> > Emulating ICPENDR is not easy with the existing vGIC. It would be great
> > to finally have a vGIC spec compliant, but I also appreciate this is
> > going to take some time.
> Yes, I agree with that.
>
> > Ignoring the access is probably the best we can do. However, this is
> > also a risky approach because Zephyr (or another OS) may genuinely want
> > to clear an already pending interrupt. So I would suggest to walk the
> > interrupts that are meant to be modified and check whether they are
> > already pending. If they are then print a message.
> OK, I would add this check and warning message to my current patch to fix it
> in current stage. Is it OK?
I would be fine with the warning. I have added Stefano in CC so he is 
aware of the discussion.
Cheers,

> > This would make clear to the developper that something may go wrong
> > later on.
> >
> > Cheers,
> >
> > --
> > Julien Grall
> [1] https://github.com/zephyrproject-rtos/zephyr/blob/eaf6cf745df3807e6e
> cc941c3a30de6c179ae359/drivers/interrupt_controller/intc_gicv3.c#L274
>
> Cheers
> Hongda
--
Julien Grall