tran_setup_pkt(9E) ought mention scsi_hba_attach_setup(9F) flags explicitly
The tran_setup_pkt(9E) manual page has a relatively cryptic reference to allocation choices the HBA driver author might make:
If the HBA driver chose not to preallocate memory for pkt_cdbp and/or pkt_scbp, it must allocate the requested memory at this time and point pkt_cdbp and pkt_scbp to the allocated memory.
It turns out that the choice to be made is whether or not
SCSI_HBA_TRAN_CDB were passed in the
flags argument to scsi_hba_attach_setup(9F). We should directly mention these flags, and the function to which they are passed, in the tran_setup_pkt(9E) page itself.