Re: [PATCH v2 06/12] cxl/acpi: Extract component registers of restricted hosts from RCRB

[Rafael J. Wysocki]

On Tue, Oct 18, 2022 at 8:42 PM Robert Richter <rrichter@xxxxxxx> wrote:
>
> On 18.10.22 15:31:16, Rafael J. Wysocki wrote:
> > On Tue, Oct 18, 2022 at 3:24 PM Robert Richter <rrichter@xxxxxxx> wrote:
> > >
> > > A downstream port must be connected to a component register block.
> > > For restricted hosts the base address is determined from the RCRB. The
> > > RCRB is provided by the host's CEDT CHBS entry. Rework CEDT parser to
> > > get the RCRB and add code to extract the component register block from
> > > it.
> > >
> > > RCRB's BAR[0..1] point to the component block containing CXL subsystem
> > > component registers. MEMBAR extraction follows the PCI base spec here,
> > > esp. 64 bit extraction and memory range alignment (6.0, 7.5.1.2.1).
> > >
> > > Note: Right now the component register block is used for HDM decoder
> > > capability only which is optional for RCDs. If unsupported by the RCD,
> > > the HDM init will fail. It is future work to bypass it in this case.
> > >
> > > Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
> >
> > What does this S-o-B mean?  If this person is your co-developer, you
> > need to add a Co-developed-by tag to clarify that.
> >
> > > Signed-off-by: Robert Richter <rrichter@xxxxxxx>
>
> I picked up an early patch and modified it significantly, so I just
> left the S-o-B.

In that case the right thing to do is to mention the original author
in the changelog instead of retaining the S-o-b.

> I could change this to a Co-developed-by tag.

Co-developed-by should be used in addition to and not instead of S-o-b
when one of the authors is sending a patch.  However, all of the
authors need to be familiar with the patch in the form in which it is
being sent then.

> IMO, the S-o-B is ok, but could be wrong here.

It isn't, at least not without a Co-developed-by tag.

There are 3 cases in which S-o-b is OK AFAICS:

1. When it matches the From: address.
2. When there is a matching Co-developed-by.
3. When maintainers pick up patches and add their own S-o-b.

This case is none of the above.