Re: [PATCH v3 0/4] drm/panel: refcounting panel lookups and references

"Diederik de Haas" <[email protected]> Mon, 27 Jul 2026 20:45:58 +0200
Newsgroups org.kernel.vger.linux-mips,dev.linux.lists.imx,dev.linux.lists.linux-sunxi,org.freedesktop.lists.dri-devel,org.infradead.lists.linux-rockchip,org.kernel.vger.linux-kernel,org.kernel.vger.linux-renesas-soc,org.kernel.vger.linux-samsung-soc,org.kernel.vger.linux-tegra
Message-ID <[email protected]>
On Wed Jul 22, 2026 at 2:15 PM CEST, Neil Armstrong wrote:
> On Fri, 17 Jul 2026 16:02:03 +0200, Albert Esteve wrote:
>> The drm_panel subsystem provides kref-based reference counting [1]
>> (drm_panel_get/put) but almost nothing in the tree actually uses it.
>> This results in a systemic use-after-free pattern throughout the codebas=
e.
>>=20
>> This series aims to close all those issues.
>>=20
>> Patches 1-2: fix the infrastructure. drm_panel_add/remove now keep
>> a counted reference for the list entry. drm_panel_bridge_add_typed()
>> now holds a counted reference for the lifetime of the panel_bridge.
>>=20
>> [...]
>
> Thanks, Applied to https://gitlab.freedesktop.org/drm/misc/kernel.git (dr=
m-misc-next)
>
> [1/4] drm/panel: have drm_panel_add/remove manage a list reference
>       https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/61aebeadff4=
0cded27168e53406e0120ad66e114
> [2/4] drm/bridge/panel: hold a reference to the wrapped panel
>       https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/8f79d34ea89=
50fd825e0d6ecd713705a42f06417
> [3/4] drm/panel: of_drm_find_panel() return a counted reference
>       https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/b71a623598d=
319cae2acd9df1b297cc948c58bc7
> [4/4] drm/panel: find_panel_by_fwnode() return a counted reference
>       https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/ac3baea883d=
ab989178dd4186090d6bcf52b8d55

That last commit resulted in an extra ``drm_panel.c.orig`` file which=20
wasn't part of the patch and seems incorrect?

Cheers,
  Diederik