Re: [PATCH v4 2/3] xen/events: don't unmask an event channel when an eoi is pending

[Boris Ostrovsky]

On 3/6/21 11:18 AM, Juergen Gross wrote:
> An event channel should be kept masked when an eoi is pending for it.
> When being migrated to another cpu it might be unmasked, though.
>
> In order to avoid this keep three different flags for each event channel
> to be able to distinguish "normal" masking/unmasking from eoi related
> masking/unmasking and temporary masking. The event channel should only
> be able to generate an interrupt if all flags are cleared.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 54c9de89895e0a36047 ("xen/events: add a new late EOI evtchn framework")
> Reported-by: Julien Grall <julien@xxxxxxx>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>
> ---
> V2:
> - introduce a lock around masking/unmasking
> - merge patch 3 into this one (Jan Beulich)
> V4:
> - don't set eoi masking flag in lateeoi_mask_ack_dynirq()


Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>


Ross, are you planning to test this?


-boris