MFC: r252348, r252363: sysconf(3) returns a long, not an int.
Really MFC r252363 (sysconf(3) returns a long, not an int).
MFC r242726 (ambrisko):
Add support for SCSI pass through devices to be attached and detached.

MFC r251172 (sbruno):
xpt_create_path() requires mfi_io_lock to be held, so do it.

mfi(4) doesn't panic on host startup now.