Re: [PATCH v3 06/17] hw/sd/sdcard: Do not store vendor data on block drive (CMD56)

[Peter Xu <peterx@redhat.com>]

On Thu, Jul 11, 2024 at 10:34:12AM -0300, Fabiano Rosas wrote:
> Is there an easy way to look at a field and tell in which machine type's
> timeframe it was introduced?

I am not aware of any.

> If the machine type of that era has been removed, then the field is free
> to go as well. I'd prefer if we had a hard link instead of just counting
> years. Maybe we should to that mapping at the machine deprecation time?
> As in, "look at the unused fields introduced in that timeframe and mark
> them free".

We can do that, but depending on how easy it would be. That can be an
overkill to me if it's non-trivial.  When it becomes complicated, I'd
rather make machine compat property easier to use so we always stick with
that.  Currently it's not as easy to use.

Maybe we shouldn't make it a common rule to let people reuse the UNUSED
fields, even if in this case it's probably fine?

E.g. I don't think it's a huge deal to keep all UNUSED fields forever -
sending 512B zeros for only one specific device isn't an issue even if kept
forever.

If "over 6 years" would be okay and simple enough, then maybe we can stick
with that (and only if people would like to reuse a field and ask; that's
after all not required..).  If more than that I doubt whether we should
spend time working on covering all the fields.

-- 
Peter Xu