RX_BUF_SIZE_MAX
m->m_len = m->m_pkthdr.len = RX_BUF_SIZE_MAX;
sc->alc_buf_size = RX_BUF_SIZE_MAX - sizeof(uint64_t);
sc->alc_buf_size = RX_BUF_SIZE_MAX;
reg -= RX_BUF_SIZE_MAX;