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IOW I consider it wrong to depend on that > in paging_domctl() to synchronize against domain_kill(). Yet indeed that > should eliminate races at present. Right, both are domctls. There are other places where is_dying get set as part of failures in the domain create paths, but then the paging domctl failing would be natural, as the domain is being destroyed as part of a failed domain create. Since I don't see replies to my other comments, do you agree on returning an error then? Thanks, Roger.