Re: [PATCH][next] drm/nouveau: Avoid -Wflex-array-member-not-at-end warning

[Danilo Krummrich <dakr@xxxxxxxxxx>]

On 9/13/24 12:23 PM, Danilo Krummrich wrote:
> Hi,
>
> On 9/13/24 10:09 AM, Gustavo A. R. Silva wrote:
> > Hi all,
> >
> > Friendly ping: who can take this, please? 🙂
>
> Usually, that's me. But I thought you might want to send a v2 based on Kees'
> comments?

Do you plan to follow up on this? I'd prefer if we could get rid of the open-
coded "17". So, maybe just go with the define until we have something like
STACK_FLEX_COUNT()?

> - Danilo
>
> > Thanks
> > -Gustavo
> >
> > On 21/08/24 22:16, Gustavo A. R. Silva wrote:
> > > Use the `DEFINE_RAW_FLEX()` helper for an on-stack definition of
> > > a flexible structure where the size of the flexible-array member
> > > is known at compile-time, and refactor the rest of the code,
> > > accordingly.
> > >
> > > So, with this, fix the following warning:
> > >
> > > drivers/gpu/drm/nouveau/dispnv50/disp.c:779:47: warning: structure containing 
> > > a flexible array member is not at the end of another structure [-Wflex-array- 
> > > member-not-at-end]
> > >
> > > Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
> > > ---
> > >   drivers/gpu/drm/nouveau/dispnv50/disp.c | 20 +++++++++-----------
> > >   1 file changed, 9 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/ 
> > > nouveau/dispnv50/disp.c
> > > index eed579a6c858..ddddc69640be 100644
> > > --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
> > > +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
> > > @@ -774,11 +774,9 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct 
> > > nouveau_crtc *nv_crtc,
> > >       struct drm_hdmi_info *hdmi = &nv_connector->base.display_info.hdmi;
> > >       union hdmi_infoframe infoframe = { 0 };
> > >       const u8 rekey = 56; /* binary driver, and tegra, constant */
> > > +    DEFINE_RAW_FLEX(struct nvif_outp_infoframe_v0, args, data, 17);
> > > +    const u8 data_len = 17; /* same length as in DEFINE_RAW_FLEX above. */
> > >       u32 max_ac_packet;
> > > -    struct {
> > > -        struct nvif_outp_infoframe_v0 infoframe;
> > > -        u8 data[17];
> > > -    } args = { 0 };
> > >       int ret, size;
> > >       max_ac_packet  = mode->htotal - mode->hdisplay;
> > > @@ -815,29 +813,29 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct 
> > > nouveau_crtc *nv_crtc,
> > >           return;
> > >       /* AVI InfoFrame. */
> > > -    args.infoframe.version = 0;
> > > -    args.infoframe.head = nv_crtc->index;
> > > +    args->version = 0;
> > > +    args->head = nv_crtc->index;
> > >       if (!drm_hdmi_avi_infoframe_from_display_mode(&infoframe.avi, 
> > > &nv_connector->base, mode)) {
> > >           drm_hdmi_avi_infoframe_quant_range(&infoframe.avi, &nv_connector- 
> > > >base, mode,
> > >                              HDMI_QUANTIZATION_RANGE_FULL);
> > > -        size = hdmi_infoframe_pack(&infoframe, args.data, 
> > > ARRAY_SIZE(args.data));
> > > +        size = hdmi_infoframe_pack(&infoframe, args->data, data_len);
> > >       } else {
> > >           size = 0;
> > >       }
> > > -    nvif_outp_infoframe(&nv_encoder->outp, NVIF_OUTP_INFOFRAME_V0_AVI, 
> > > &args.infoframe, size);
> > > +    nvif_outp_infoframe(&nv_encoder->outp, NVIF_OUTP_INFOFRAME_V0_AVI, args, 
> > > size);
> > >       /* Vendor InfoFrame. */
> > > -    memset(&args.data, 0, sizeof(args.data));
> > > +    memset(args->data, 0, data_len);
> > >       if (!drm_hdmi_vendor_infoframe_from_display_mode(&infoframe.vendor.hdmi,
> > >                                &nv_connector->base, mode))
> > > -        size = hdmi_infoframe_pack(&infoframe, args.data, 
> > > ARRAY_SIZE(args.data));
> > > +        size = hdmi_infoframe_pack(&infoframe, args->data, data_len);
> > >       else
> > >           size = 0;
> > > -    nvif_outp_infoframe(&nv_encoder->outp, NVIF_OUTP_INFOFRAME_V0_VSI, 
> > > &args.infoframe, size);
> > > +    nvif_outp_infoframe(&nv_encoder->outp, NVIF_OUTP_INFOFRAME_V0_VSI, args, 
> > > size);
> > >       nv_encoder->hdmi.enabled = true;
> > >   }