Re: [PATCH] xen/events: reset active flag for lateeoi events later

From: Ross Lagerwall
Date: Mon Jul 05 2021 - 05:07:23 EST

On 2021-06-23 14:09, Juergen Gross wrote:
> In order to avoid a race condition for user events when changing
> cpu affinity reset the active flag only when EOI-ing the event.
> This is working fine as all user events are lateeoi events. Note that
> lateeoi_ack_mask_dynirq() is not modified as there is no explicit call
> to xen_irq_lateeoi() expected later.
> Reported-by: Julien Grall <julien@xxxxxxx>
> Fixes: b6622798bc50b62 ("xen/events: avoid handling the same event on two cpus at the same time")
> Tested-by: Julien Grall <julien@xxxxxxx>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---

Hi Juergen,

Are you planning on backporting this fix to releases <= 5.10?

I think the fix may need some minor adjustment to make it work after
"xen/events: fix setting irq affinity" since both lateeoi_ack_dynirq()
and lateeoi_mask_ack_dynirq() were adjusted to call ack_dynirq().