Re: Re: [PATCH] cxl/mbox: bound the device-supplied command return code

[黄高彬 <huanggaobin23@semi.ac.cn>]

Hi Alison,

Thank you for picking it up, and for the corrections.

> (Sashiko is right here. PADDR and POISONLMT don't map to -ENXIO, so the
> comment and changelog claim isn't accurate. -ENXIO is still the right
> fallback for an unknown code.)

You are both right: the claim should be that an unknown code is still a failure
and that -ENXIO keeps it in the usual device-error class -- not that every
non-success entry maps to -ENXIO.  Please use that wording in the version you
carry; I will not repost the patch on its own.

> I'm taking this into a series that adds CXL KUnit tests, including a
> regression test for this table. You'll get CC'd when it posts and I'll need
> you ACK it since it has your original authorship with changes from me added.

Understood -- I will ACK as soon as it posts.

> It looks like the return code you saw is valid for CXL 4.0 and just not added
> to CXL driver yet. ... CXL 4.0, Table 8-208 ... 001Fh and 0020h
> I don't think anyone else has sent a patch for that yet, so you can if you
> like.

Two things there, and I would rather not collide with your series:

- The KASAN reproduction used 0x1f, which stops being out of range once 001Fh is
  in the table.  Out of range is any code past the end of the table, so with
  001Fh and 0020h added it is 0021h upwards -- the bound itself is unchanged.
- Adding the two entries is a separate change from the bound.  Do you want it in
  your series next to the KUnit test, so the boundary and the test move
  together, or as a standalone patch from me after yours?  Either is fine.  If
  you would rather have it from me, I will take the names and errno mappings
  from Table 8-208 and send it separately.

Thanks,
Gaobin