Hi all --
Thought I'd share this fix with you all just in case someone in the
future might make use of it.
Long story short: Got myself a CMD 710/M UNIBUS SCSI controller with
the intent to use it in my VAX-11/750, running 4.3BSD-Quasijarus.
Unfortunately it won't boot (it hangs shortly after "loading boot" is
printed to the console). VMS boots, NetBSD > 1.6 or so boots, Ultrix
boots, but no luck with 4.3BSD.
I spent some time adding some debug spew to the bootstrap (on SIMH) and
testing (on the 750), and the hang is inside udcmd() in
sys/vaxstand/uda.c. I then stumbled on this usenet post:
https://groups.google.com/forum/#!msg/alt.sys.pdp11/61LZNTo9Dgg/Q6dI9om_LIEJ
Which indicates a similar problem with a Viking controller on a
different 4.3BSD variant. The code in Quasijarus is a bit different,
but the cause is the same.
The fix is:
Change line 155 of sys/vaxstand/uda.c from:
if(u->uda_ca.ca_rspint ==0)
to:
if(u->uda_ca.ca_rspdc & MSCP_OWN)
Rebuild, and re-run disklabel to replace the bootstrap.
Hope that helps someone else someday...
- Josh
