0119cb365c
When running the demand paging test with the -u option, the User Fault FD handler essentially adds an arbitrary delay to page fault resolution. To enable better simulation of a real demand paging scenario, add a configurable delay to the UFFD handler. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>