rpages = shmp_index(handle, bufb->array, sb_bindex);
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));
rpages = shmp_index(handle, bufb->array, sb_bindex);
CHAN_WARN_ON(chanb, config->mode == RING_BUFFER_OVERWRITE
&& subbuffer_id_is_noref(config, id));