[bug report] Merge branch 'for-linux-next' of git://anongit.freedesktop.org/drm/drm-misc

[bug report] Merge branch 'for-linux-next' of git://anongit.freedesktop.org/drm/drm-misc

[Dan Carpenter]

Hello Stephen Rothwell,

The patch 23b727d76bda: "Merge branch 'for-linux-next' of
git://anongit.freedesktop.org/drm/drm-misc" from Nov 17, 2022, leads
to the following Smatch static checker warning:

	drivers/gpu/drm/vc4/vc4_hdmi.c:351 vc4_hdmi_reset_link()
	error: uninitialized symbol 'vc4_hdmi'.

drivers/gpu/drm/vc4/vc4_hdmi.c
    346 
    347         crtc_state = crtc->state;
    348         if (!crtc_state->active)
    349                 return 0;
    350 
--> 351         mutex_lock(&vc4_hdmi->mutex);
                           ^^^^^^^^^
This locking

    352 
    353         vc4_hdmi = connector_to_vc4_hdmi(connector);
                ^^^^^^^^^^
needs to be done after this assignment.  But this is only in linux-next
so presumably it's a temporary thing.

    354         if (!vc4_hdmi_supports_scrambling(vc4_hdmi)) {
    355                 mutex_unlock(&vc4_hdmi->mutex);
    356                 return 0;
    357         }
    358 
    359         scrambling_needed = vc4_hdmi_mode_needs_scrambling(&vc4_hdmi->saved_adjusted_mode,
    360                                                            vc4_hdmi->output_bpc,

regards,
dan carpenter

Re: [bug report] Merge branch 'for-linux-next' of git://anongit.freedesktop.org/drm/drm-misc

[José Expósito]

Hi Dan,

On Fri, Nov 18, 2022 at 02:17:34PM +0300, Dan Carpenter wrote:
> Hello Stephen Rothwell,
> 
> The patch 23b727d76bda: "Merge branch 'for-linux-next' of
> git://anongit.freedesktop.org/drm/drm-misc" from Nov 17, 2022, leads
> to the following Smatch static checker warning:
> 
> 	drivers/gpu/drm/vc4/vc4_hdmi.c:351 vc4_hdmi_reset_link()
> 	error: uninitialized symbol 'vc4_hdmi'.
> 
> drivers/gpu/drm/vc4/vc4_hdmi.c
>     346 
>     347         crtc_state = crtc->state;
>     348         if (!crtc_state->active)
>     349                 return 0;
>     350 
> --> 351         mutex_lock(&vc4_hdmi->mutex);
>                            ^^^^^^^^^
> This locking
> 
>     352 
>     353         vc4_hdmi = connector_to_vc4_hdmi(connector);
>                 ^^^^^^^^^^
> needs to be done after this assignment.  But this is only in linux-next
> so presumably it's a temporary thing.
> 
>     354         if (!vc4_hdmi_supports_scrambling(vc4_hdmi)) {
>     355                 mutex_unlock(&vc4_hdmi->mutex);
>     356                 return 0;
>     357         }
>     358 
>     359         scrambling_needed = vc4_hdmi_mode_needs_scrambling(&vc4_hdmi->saved_adjusted_mode,
>     360                                                            vc4_hdmi->output_bpc,
> 
> regards,
> dan carpenter

I think that Stephen already handled this issue as discussed here:
https://lore.kernel.org/all/Y3ZvffZiR+SgtY6h@dev-arch.thelio-3990X/

Jose