An interrupt is set up when the interrupt's file descriptor is
received. Each message applies to the next interrupt vector.
Therefore, each vector cannot be set up more than once.
ivshmem_add_kvm_msi_virq() half-heartedly tries not to rely on this by
doing nothing then, but that's not going to recover from this error
should it become possible in the future. watch_vector_notifier()
doesn't even try.
Simply assert what is the case, so we get alerted if we ever screw it
up.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1458066895-20632-22-git-send-email-armbru@redhat.com>
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