Re: [PATCH] docs: driver-api: firmware: clarify userspace requirements

From: Dave Airlie
Date: Mon Mar 17 2025 - 18:57:05 EST


On Tue, 18 Mar 2025 at 08:53, Jonathan Corbet <corbet@xxxxxxx> wrote:
>
> Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx> writes:
>
> > The guidelines mention that firmware updates can't break the kernel,
> > but it doesn't state directly that they can't break userspace programs.
> > Make it explicit that firmware updates cannot break UAPI.
> >
> > Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
> > ---
> > .../driver-api/firmware/firmware-usage-guidelines.rst | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/Documentation/driver-api/firmware/firmware-usage-guidelines.rst b/Documentation/driver-api/firmware/firmware-usage-guidelines.rst
> > index fdcfce42c6d28..5f8f13e2ee510 100644
> > --- a/Documentation/driver-api/firmware/firmware-usage-guidelines.rst
> > +++ b/Documentation/driver-api/firmware/firmware-usage-guidelines.rst
> > @@ -42,3 +42,8 @@ then of course these rules will not apply strictly.)
> > deprecating old major versions, then this should only be done as a
> > last option, and be stated clearly in all communications.
> >
> > +* Firmware files that affect the User API (UAPI) shall not introduce
> > + changes that break existing userspace programs. Updates to such firmware
> > + must ensure backward compatibility with existing userspace applications.
> > + This includes maintaining consistent interfaces and behaviors that
> > + userspace programs rely on.
> > \ No newline at end of file
>
> This ^^^^^^^^^^^^^^^^^^^^^^^^ is a good thing to avoid. That can be
> fixed up at apply time.
>
> Dave, you're the only one with fingerprints on this document; is the
> change OK with you?

LGTM,

Acked-by: Dave Airlie <airlied@xxxxxxxxxx>

Dave.

>
> Thanks,
>
> jon