Re: [RFC PATCH 12/15] libfdt: Handle unknown tags in fdt_get_next()

Herve Codina
2026-04-07T14:29:59Z

Hi Luca,

On Wed, 01 Apr 2026 17:17:46 +0200
"Luca Ceresoli" <luca.ceresoli@bootlin.com> wrote:

> On Tue Feb 10, 2026 at 6:33 PM CET, Herve Codina wrote:
> > The structured tag value definition introduced recently gives the
> > ability to ignore unknown tags without any error when they are read.
> >
> > libfdt uses fdt_get_next() to get a tag.
>
> I think you mean fdt_next_tag(), here and elsewhere in the commit message.
>
> >
> > Filtering out tags that should be ignored in fdt_get_next() allows to
> > have the filtering done globally and allows, in future release, to have
> ^
> releases
>
> > a central place to add new known tags that should not be filtered out.
> >
> > An already known tag exists with the meaning of "just ignore". This tag
> > is FDT_NOP. fdt_get_next() callers already handle the FDT_NOP tag.
> >
> > Avoid unneeded modification at callers side and use a fake FDT_NOP tag
> > when an unknown tag that should be ignored is encountered.
> >
> > Add also fdt_get_next_() internal function for callers who need to know
>
> And here fdt_next_tag_()?
>

You're perfectly right. fdt_next_tag() and fdt_next_tag_() are the correct
functions.

This will be fixed in the next iteration as well as the commit title (same
issue) and the 'release' typo.

Best regards,
Hervé