Re: [PATCH] pstore/ram: Improve backward compatibility with older Chromebooks

From: Brian Norris
Date: Tue May 07 2019 - 12:57:13 EST

On Tue, May 7, 2019 at 9:25 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
> On Mon, May 6, 2019 at 2:40 PM Brian Norris <briannorris@xxxxxxxxxxxx> wrote:
> > The last part of the sentence technically isn't true -- the original
> > bindings (notably, with no DT maintainer Reviewed-by) didn't specify
> > where such a node should be found:
> >
> > 35da60941e44 pstore/ram: add Device Tree bindings
> >
> > so child-of-root used to be a valid location. But anyway, this code is
> > just part of a heuristic for "old DT" (where later bindings clarified
> > this), so it still seems valid.
> I agree that it was unclear in the past, but it is true that being
> under the root node is not according to the _current_ upstream
> bindings, right? ;-)

Sure, I suppose. Although, given the general ABI policy around DT, it
seems to me that something that was "according to" an old binding
cannot really be made "no longer" according to the binding. It can be
discouraged, and removed from new DTs, but it doesn't really become

But our DT was definitely *not* according to even the (un-reviewed)
merged binding. So I'm mostly mincing words here.