Re: [PATCH] drm/tyr: gpu_info: zero out new/unused fields

[Alice Ryhl]

On Thu, Sep 24, 2026 at 2:27 AM Deborah Brouwer
<deborah.brouwer@xxxxxxxxxxxxx> wrote:
>
> On Wed, Sep 23, 2026 at 09:42:23AM +0200, Alice Ryhl wrote:
> > On Wed, Sep 23, 2026 at 1:16 AM Deborah Brouwer
> > <deborah.brouwer@xxxxxxxxxxxxx> wrote:
> > >
> > > If a new field is added to the struct drm_panthor_gpu_info in the panthor
> > > uapi, Tyr must initialize this field or it will cause a compile error.
> > >
> > > To pre-emptively avoid compile errors, use ..pin_init::zeroed() to zero
> > > out all new fields added to this struct. Tyr can subsequently change the
> > > initialization as necessary. Also use it instead of manually zeroing out
> > > existing fields at the end of the struct.
> > >
> > > Signed-off-by: Deborah Brouwer <deborah.brouwer@xxxxxxxxxxxxx>
> >
> > Merged into drm-rust-next, thanks!
> >
> > With regards to sashiko bot, we should look into whether the
> > MaybeZeroable that bindgen adds to structs applies on this struct. If
> > so, we can remove our unsafe impl block. But it's not an issue in this
> > patch.
>
> I couldn't use MaybeZeroable directly but if I add IntoBytes and
> Immutable then we can stop implementing unsafe trait AsBytes. Could you
> please review:
>
> https://lore.kernel.org/rust-for-linux/20260923-b4-gpu_info_intobytes-v1-1-bb2173f91e11@xxxxxxxxxxxxx/

Oh, yeah, MaybeZeroable isn't the one we want. We'd want MaybeAsBytes,
but I'm not sure that exists yet. I think we asked for it, but not
sure the state.

Alice