Re: bad144 - how useful still? Because it's annoyingly ubiquitous.

[Anders Magnusson <ragge%tethuvudet.se@localhost>]

Den 2026-05-27 kl. 14:00, skrev Jason Thorpe:

> So, let’s focus on DEC STD 144, a.k.a. bad144, a.k.a. dkbad.  It’s a 1970s-era bad sector remapping scheme that was already mostly obsolete by the mid-80s (ever since SCSI drives were able to maintain their own bad sector remapping information).  It is totally and completely useless on any drive made since the 1990s.  And yet, its tendrils infest many a NetBSD port’s BSD disklabel handling because, as far as I can tell, cargo-cultism.
>
> I figure there are a handful of legit use cases for bad144 in NetBSD still:
>
> - The vax port, obviously, but only with the really old drives.  (VAX peeps please help me out here - is bad144 useful drives behind an MSCP-compliant controller?)
>     
    bad144 is not used by NetBSD/vax.  
    - MSCP drives have their own bad block replacement scheme.
    - On RP drives there is a need for BAD144 in the disk driver, but I
    have never written that support - no RP drives I have used have had
    any bad blocks so I haven't cared :-)
    I'm quite unsure if there will ever be a need for BAD144 on any VAX
    drives.  
    People using NetBSD/vax on RP07 with bad blocks are probably very
    close to NIL :-)
    
    -- R