Re: [PATCH v3 2/8] xen/events: don't unmask an event channel when an eoi is pending

From: Julien Grall
Date: Sat Feb 20 2021 - 07:11:37 EST


Hi Juergen,

On 19/02/2021 15:40, 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>

Cheers,

--
Julien Grall