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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260713-drm_refcount_wiring-v2-1-d3bb61f4bd4d@redhat.com> References: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> In-Reply-To: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> To: Neil Armstrong , Jessica Zhang , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Andrzej Hajda , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Inki Dae , Jagan Teki , Marek Szyprowski , Laurentiu Palcu , Lucas Stach , Frank Li , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Paul Cercueil , Linus Walleij , Marek Vasut , Stefan Agner , Tomi Valkeinen , Laurent Pinchart , Kieran Bingham , Geert Uytterhoeven , Magnus Damm , Biju Das , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Yannick Fertre , Raphael Gallais-Pou , Philippe Cornu , Maxime Coquelin , Alexandre Torgue , Chen-Yu Tsai , Samuel Holland , Jyri Sarha , Jingoo Han , Seung-Woo Kim , Kyungmin Park , Krzysztof Kozlowski , Peter Griffin , Alim Akhtar , Alison Wang , Paul Kocialkowski , Alain Volmat , Raphael Gallais-Pou , Thierry Reding , Mikko Perttunen , Jonathan Hunter Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, linux-sunxi@lists.linux.dev, linux-samsung-soc@vger.kernel.org, linux-tegra@vger.kernel.org, Albert Esteve X-Developer-Signature: v=1; a=ed25519-sha256; t=1783943594; l=1577; i=aesteve@redhat.com; s=20260303; h=from:subject:message-id; bh=7ETe8CFt5XKIiFSTBOPt7a6t1tvKKB7JNYwUpYEimh4=; b=lgm6WYGzEa5cY2/2dWmhsWCYfvwJ+EQT45NMlusojBnvAwrv8eT+DunBt732/G3xFam8iaDGy rmYQIHe7THDAErVwIMiHtj2DyMaLCAlPiETerk/jH2KwMY2hPaPFqe3 X-Developer-Key: i=aesteve@redhat.com; a=ed25519; pk=YSFz6sOHd2L45+Fr8DIvHTi6lSIjhLZ5T+rkxspJt1s= X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 The global panel_list holds raw pointers to drm_panel objects. Nothing prevents a panel from being freed while it is still linked in the list: if a driver's probe calls drm_panel_add() and then fails at a later step, panel->list remains in panel_list. Any subsequent call to of_drm_find_panel() that iterates the list will dereference freed memory. Have drm_panel_add() acquire a reference via drm_panel_get() before inserting the panel into the list, and have drm_panel_remove() drop it via drm_panel_put() after removing the panel from the list. The global registry now holds a counted reference for as long as the panel is listed, ensuring the object outlives any concurrent lookup. Reviewed-by: Maxime Ripard Signed-off-by: Albert Esteve --- drivers/gpu/drm/drm_panel.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 2c5649e433dfb..545fe93dc28fe 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -81,6 +81,7 @@ static void drm_panel_init(struct drm_panel *panel, struc= t device *dev, */ void drm_panel_add(struct drm_panel *panel) { + drm_panel_get(panel); mutex_lock(&panel_lock); list_add_tail(&panel->list, &panel_list); mutex_unlock(&panel_lock); @@ -98,6 +99,7 @@ void drm_panel_remove(struct drm_panel *panel) mutex_lock(&panel_lock); list_del_init(&panel->list); mutex_unlock(&panel_lock); + drm_panel_put(panel); } EXPORT_SYMBOL(drm_panel_remove); =20 --=20 2.54.0 From nobody Sat Jul 25 21:21:24 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75C0A34676D for ; 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Mon, 13 Jul 2026 07:54:10 -0400 X-MC-Unique: _41bh230N3-ZgHURFLlf5A-1 X-Mimecast-MFC-AGG-ID: _41bh230N3-ZgHURFLlf5A_1783943647 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 77FA318052F9; Mon, 13 Jul 2026 11:54:06 +0000 (UTC) Received: from [192.168.1.153] (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B9D201800586; Mon, 13 Jul 2026 11:53:51 +0000 (UTC) From: Albert Esteve Date: Mon, 13 Jul 2026 13:53:05 +0200 Subject: [PATCH v2 2/5] drm/bridge/panel: hold a reference to the wrapped panel Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; 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a=ed25519-sha256; t=1783943594; l=2238; i=aesteve@redhat.com; s=20260303; h=from:subject:message-id; bh=D94C7nl3OfTTTUlxa92ZHQtC3f+/K8QFXjzTBntEVk0=; b=H+H0lwiIuyc7pIIA67x3DnJ6AvDwZQe2byCuCRpgEzKUvN4oax64GGQvap0g65TQkQxwN4Tg1 CDFh/zYmJiXDj6bn9RQB4XGp3SAFLKt9mCcizgJs8HSQg06SGzqIEoD X-Developer-Key: i=aesteve@redhat.com; a=ed25519; pk=YSFz6sOHd2L45+Fr8DIvHTi6lSIjhLZ5T+rkxspJt1s= X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 drm_panel_bridge_add_typed() stores a pointer to the drm_panel it wraps, but never acquires a reference to it. If the panel device goes away while a panel_bridge still exists, the dangling pointer can be dereferenced through panel_bridge->panel. Acquire a reference in drm_panel_bridge_add_typed() with drm_panel_get() and release it in each teardown path. Reviewed-by: Maxime Ripard Signed-off-by: Albert Esteve --- drivers/gpu/drm/bridge/panel.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index 4978ec98a0828..6b98ad19508df 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -294,7 +294,7 @@ struct drm_bridge *drm_panel_bridge_add_typed(struct dr= m_panel *panel, return (void *)panel_bridge; =20 panel_bridge->connector_type =3D connector_type; - panel_bridge->panel =3D panel; + panel_bridge->panel =3D drm_panel_get(panel); =20 panel_bridge->bridge.of_node =3D panel->dev->of_node; panel_bridge->bridge.ops =3D DRM_BRIDGE_OP_MODES; @@ -316,6 +316,7 @@ EXPORT_SYMBOL(drm_panel_bridge_add_typed); void drm_panel_bridge_remove(struct drm_bridge *bridge) { struct panel_bridge *panel_bridge; + struct drm_panel *panel; =20 if (!bridge) return; @@ -326,10 +327,12 @@ void drm_panel_bridge_remove(struct drm_bridge *bridg= e) } =20 panel_bridge =3D drm_bridge_to_panel_bridge(bridge); 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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260713-drm_refcount_wiring-v2-3-d3bb61f4bd4d@redhat.com> References: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> In-Reply-To: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> To: Neil Armstrong , Jessica Zhang , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Andrzej Hajda , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Inki Dae , Jagan Teki , Marek Szyprowski , Laurentiu Palcu , Lucas Stach , Frank Li , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Paul Cercueil , Linus Walleij , Marek Vasut , Stefan Agner , Tomi Valkeinen , Laurent Pinchart , Kieran Bingham , Geert Uytterhoeven , Magnus Damm , Biju Das , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Yannick Fertre , Raphael Gallais-Pou , Philippe Cornu , Maxime Coquelin , Alexandre Torgue , Chen-Yu Tsai , Samuel Holland , Jyri Sarha , Jingoo Han , Seung-Woo Kim , Kyungmin Park , Krzysztof Kozlowski , Peter Griffin , Alim Akhtar , Alison Wang , Paul Kocialkowski , Alain Volmat , Raphael Gallais-Pou , Thierry Reding , Mikko Perttunen , Jonathan Hunter Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, linux-sunxi@lists.linux.dev, linux-samsung-soc@vger.kernel.org, linux-tegra@vger.kernel.org, Albert Esteve X-Developer-Signature: v=1; a=ed25519-sha256; t=1783943594; l=14844; i=aesteve@redhat.com; s=20260303; h=from:subject:message-id; bh=C9hytV/WNG6Ap25BpMyeNrBHlKSUexgcfqP7CuoqfAE=; b=jowyFI3R17ujw461VNkIiwW6hauoRj3AdxrjqhlBgzyDKDalUIhjlSK5NlYNqSQl+zN6S8L5y O+40NxFXujbCEz+BB2GSVuLeibMjiAy3q1F+c2/7pIPI7RXRfyAwe+H X-Developer-Key: i=aesteve@redhat.com; a=ed25519; pk=YSFz6sOHd2L45+Fr8DIvHTi6lSIjhLZ5T+rkxspJt1s= X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Callers of of_drm_find_panel() receive a pointer with no reference held, creating a window where the panel device can be unregistered and freed between the lookup and first use (e.g., drm_panel_prepare()). Fix the lookup function by acquiring a reference with drm_panel_get() before returning, under panel_lock. Callers are now responsible for calling drm_panel_put() when they no longer need the pointer. For bridge drivers that immediately wrap the panel in a panel_bridge (which acquires its own reference), release the lookup reference right after the bridge creation call. For analogix-anx6345, which stores the panel for direct use, release the reference in the i2c remove path. For platform drivers using analogix_dp_core with a component lifecycle (exynos_dp, rockchip analogix_dp), release the lookup reference in the platform remove() function. The panel_bridge created during bind() holds a separate reference that devm cleanup releases after remove() returns. Also fix devm_drm_of_get_bridge() and drmm_of_get_bridge() in bridge/panel.c itself: both call drm_of_find_panel_or_bridge() and then pass the panel to devm/drmm_panel_bridge_add(), which acquires its own reference via drm_panel_bridge_add_typed(). The lookup reference was never released; add drm_panel_put() after each bridge creation call. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Albert Esteve Acked-by: Maxime Ripard --- drivers/gpu/drm/bridge/analogix/analogix-anx6345.c | 3 +++ drivers/gpu/drm/bridge/panel.c | 8 ++++++-- drivers/gpu/drm/drm_of.c | 3 ++- drivers/gpu/drm/drm_panel.c | 12 ++++++++---- drivers/gpu/drm/exynos/exynos_dp.c | 10 ++++++++++ drivers/gpu/drm/exynos/exynos_drm_dpi.c | 3 +++ drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 18 ++++++++++++++++++ drivers/gpu/drm/logicvc/logicvc_interface.c | 12 ++++++++++++ drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 11 +++++++++++ drivers/gpu/drm/sti/sti_dvo.c | 3 +++ drivers/gpu/drm/stm/lvds.c | 3 +++ drivers/gpu/drm/sun4i/sun4i_lvds.c | 13 +++++++++++++ drivers/gpu/drm/sun4i/sun4i_rgb.c | 13 +++++++++++++ drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 2 ++ drivers/gpu/drm/tegra/dsi.c | 1 + drivers/gpu/drm/tegra/output.c | 3 +++ 16 files changed, 111 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c b/drivers/g= pu/drm/bridge/analogix/analogix-anx6345.c index f3fe47b12edca..1fe11b075f860 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c @@ -756,6 +756,9 @@ static void anx6345_i2c_remove(struct i2c_client *clien= t) { struct anx6345 *anx6345 =3D i2c_get_clientdata(client); =20 + if (anx6345->panel) + drm_panel_put(anx6345->panel); + drm_bridge_remove(&anx6345->bridge); =20 unregister_i2c_dummy_clients(anx6345); diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index 6b98ad19508df..04b53ae698e5b 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -513,8 +513,10 @@ struct drm_bridge *devm_drm_of_get_bridge(struct devic= e *dev, if (ret) return ERR_PTR(ret); =20 - if (panel) + if (panel) { bridge =3D devm_drm_panel_bridge_add(dev, panel); + drm_panel_put(panel); + } =20 return bridge; } @@ -547,8 +549,10 @@ struct drm_bridge *drmm_of_get_bridge(struct drm_devic= e *drm, if (ret) return ERR_PTR(ret); =20 - if (panel) + if (panel) { bridge =3D drmm_panel_bridge_add(drm, panel); + drm_panel_put(panel); + } =20 return bridge; } diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c index d03ada82eac96..1873a84514a68 100644 --- a/drivers/gpu/drm/drm_of.c +++ b/drivers/gpu/drm/drm_of.c @@ -225,7 +225,8 @@ EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint); * @np: device tree node containing encoder output ports * @port: port in the device tree node * @endpoint: endpoint in the device tree node - * @panel: pointer to hold returned drm_panel, must not be NULL + * @panel: pointer to hold returned drm_panel, must not be NULL. On success + * the caller must call drm_panel_put() when done with the panel * @bridge: pointer to hold returned drm_bridge * * Given a DT node's port and endpoint number, find the connected node and diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 545fe93dc28fe..72cf86253c0cd 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -458,14 +458,17 @@ EXPORT_SYMBOL(__devm_drm_panel_alloc); =20 #ifdef CONFIG_OF /** - * of_drm_find_panel - look up a panel using a device tree node + * of_drm_find_panel - look up and reference a panel by device tree node * @np: device tree node of the panel * * Searches the set of registered panels for one that matches the given de= vice - * tree node. If a matching panel is found, return a pointer to it. + * tree node. If a matching panel is found, the panel's reference count is + * incremented before returning a pointer to it. The caller must call + * drm_panel_put() when it no longer needs the panel pointer. * - * Return: A pointer to the panel registered for the specified device tree - * node or an ERR_PTR() if no panel matching the device tree node can be f= ound. + * Return: A reference-counted pointer to the panel registered for the spe= cified + * device tree node or an ERR_PTR() if no panel matching the device tree n= ode + * can be found. * * Possible error codes returned by this function: * @@ -484,6 +487,7 @@ struct drm_panel *of_drm_find_panel(const struct device= _node *np) =20 list_for_each_entry(panel, &panel_list, list) { if (panel->dev->of_node =3D=3D np) { + drm_panel_get(panel); mutex_unlock(&panel_lock); return panel; } diff --git a/drivers/gpu/drm/exynos/exynos_dp.c b/drivers/gpu/drm/exynos/ex= ynos_dp.c index b805403281504..14f5b1b452506 100644 --- a/drivers/gpu/drm/exynos/exynos_dp.c +++ b/drivers/gpu/drm/exynos/exynos_dp.c @@ -193,6 +193,16 @@ static int exynos_dp_probe(struct platform_device *pde= v) =20 static void exynos_dp_remove(struct platform_device *pdev) { + struct exynos_dp_device *dp =3D platform_get_drvdata(pdev); + + /* + * Release the probe-time reference from of_drm_find_panel(). If bind + * ran, the panel_bridge holds a second reference that devm cleanup + * will release when the bridge is destroyed after remove() returns. + */ + if (dp->plat_data.panel) + drm_panel_put(dp->plat_data.panel); + component_del(&pdev->dev, &exynos_dp_ops); } =20 diff --git a/drivers/gpu/drm/exynos/exynos_drm_dpi.c b/drivers/gpu/drm/exyn= os/exynos_drm_dpi.c index 0dc36df6ada34..9d15a0035ea99 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dpi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dpi.c @@ -245,5 +245,8 @@ int exynos_dpi_remove(struct drm_encoder *encoder) =20 exynos_dpi_disable(&ctx->encoder); =20 + if (ctx->panel) + drm_panel_put(ctx->panel); + return 0; } diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c b/drivers/gpu/drm/fs= l-dcu/fsl_dcu_drm_rgb.c index 84eff7519e322..ec71fbbb0eb89 100644 --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c @@ -109,6 +109,13 @@ static int fsl_dcu_attach_panel(struct fsl_dcu_drm_dev= ice *fsl_dev, return ret; } =20 +static void fsl_dcu_panel_put_action(void *data) +{ + struct drm_panel *panel =3D data; + + drm_panel_put(panel); +} + int fsl_dcu_create_outputs(struct fsl_dcu_drm_device *fsl_dev) { struct device_node *panel_node; @@ -124,6 +131,12 @@ int fsl_dcu_create_outputs(struct fsl_dcu_drm_device *= fsl_dev) if (IS_ERR(fsl_dev->connector.panel)) return PTR_ERR(fsl_dev->connector.panel); =20 + ret =3D devm_add_action_or_reset(fsl_dev->dev, + fsl_dcu_panel_put_action, + fsl_dev->connector.panel); + if (ret) + return ret; + return fsl_dcu_attach_panel(fsl_dev, fsl_dev->connector.panel); } =20 @@ -132,6 +145,11 @@ int fsl_dcu_create_outputs(struct fsl_dcu_drm_device *= fsl_dev) return ret; =20 if (panel) { + ret =3D devm_add_action_or_reset(fsl_dev->dev, + fsl_dcu_panel_put_action, panel); + if (ret) + return ret; + fsl_dev->connector.panel =3D panel; return fsl_dcu_attach_panel(fsl_dev, panel); } diff --git a/drivers/gpu/drm/logicvc/logicvc_interface.c b/drivers/gpu/drm/= logicvc/logicvc_interface.c index 689049d395c0d..81f760dc07f8d 100644 --- a/drivers/gpu/drm/logicvc/logicvc_interface.c +++ b/drivers/gpu/drm/logicvc/logicvc_interface.c @@ -28,6 +28,11 @@ #define logicvc_interface_from_drm_connector(c) \ container_of(c, struct logicvc_interface, drm_connector) =20 +static void logicvc_panel_put_action(void *data) +{ + drm_panel_put(data); +} + static void logicvc_encoder_enable(struct drm_encoder *drm_encoder) { struct logicvc_drm *logicvc =3D logicvc_drm(drm_encoder->dev); @@ -160,6 +165,13 @@ int logicvc_interface_init(struct logicvc_drm *logicvc) if (ret =3D=3D -EPROBE_DEFER) goto error_early; =20 + if (interface->drm_panel) { + ret =3D devm_add_action_or_reset(dev, logicvc_panel_put_action, + interface->drm_panel); + if (ret) + goto error_early; + } + ret =3D drm_encoder_init(drm_dev, &interface->drm_encoder, &logicvc_encoder_funcs, encoder_type, NULL); if (ret) { diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/= drm/rockchip/analogix_dp-rockchip.c index 06072efd7fca3..4b2795a6caf8c 100644 --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -472,6 +473,16 @@ static int rockchip_dp_probe(struct platform_device *p= dev) =20 static void rockchip_dp_remove(struct platform_device *pdev) { + struct rockchip_dp_device *dp =3D platform_get_drvdata(pdev); + + /* + * Release the probe-time reference from of_drm_find_panel(). If bind + * ran, the panel_bridge holds a second reference that devm cleanup + * will release when the bridge is destroyed after remove() returns. + */ + if (dp->plat_data.panel) + drm_panel_put(dp->plat_data.panel); + component_del(&pdev->dev, &rockchip_dp_component_ops); } =20 diff --git a/drivers/gpu/drm/sti/sti_dvo.c b/drivers/gpu/drm/sti/sti_dvo.c index 7484d3c3f4ed5..64a9da0362fb8 100644 --- a/drivers/gpu/drm/sti/sti_dvo.c +++ b/drivers/gpu/drm/sti/sti_dvo.c @@ -492,6 +492,9 @@ static void sti_dvo_unbind(struct device *dev, { struct sti_dvo *dvo =3D dev_get_drvdata(dev); =20 + if (dvo->panel) + drm_panel_put(dvo->panel); + drm_bridge_remove(&dvo->bridge); } =20 diff --git a/drivers/gpu/drm/stm/lvds.c b/drivers/gpu/drm/stm/lvds.c index 50a878688e477..77735e26c56e3 100644 --- a/drivers/gpu/drm/stm/lvds.c +++ b/drivers/gpu/drm/stm/lvds.c @@ -1189,6 +1189,9 @@ static void lvds_remove(struct platform_device *pdev) { struct stm_lvds *lvds =3D platform_get_drvdata(pdev); =20 + if (lvds->panel) + drm_panel_put(lvds->panel); + lvds_pixel_clk_unregister(lvds); =20 drm_bridge_remove(&lvds->lvds_bridge); diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.c b/drivers/gpu/drm/sun4i/sun= 4i_lvds.c index 6716e895ae8a4..e1b342c922224 100644 --- a/drivers/gpu/drm/sun4i/sun4i_lvds.c +++ b/drivers/gpu/drm/sun4i/sun4i_lvds.c @@ -18,6 +18,11 @@ #include "sun4i_tcon.h" #include "sun4i_lvds.h" =20 +static void sun4i_panel_put_action(void *data) +{ + drm_panel_put(data); +} + struct sun4i_lvds { struct drm_connector connector; struct drm_encoder encoder; @@ -113,6 +118,14 @@ int sun4i_lvds_init(struct drm_device *drm, struct sun= 4i_tcon *tcon) return 0; } =20 + if (lvds->panel) { + ret =3D devm_add_action_or_reset(tcon->dev, + sun4i_panel_put_action, + lvds->panel); + if (ret) + return ret; + } + drm_encoder_helper_add(&lvds->encoder, &sun4i_lvds_enc_helper_funcs); ret =3D drm_simple_encoder_init(drm, &lvds->encoder, diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.c b/drivers/gpu/drm/sun4i/sun4= i_rgb.c index dfb6acc42f02e..0066bec5a9e5a 100644 --- a/drivers/gpu/drm/sun4i/sun4i_rgb.c +++ b/drivers/gpu/drm/sun4i/sun4i_rgb.c @@ -43,6 +43,11 @@ drm_encoder_to_sun4i_rgb(struct drm_encoder *encoder) encoder); } =20 +static void sun4i_panel_put_action(void *data) +{ + drm_panel_put(data); +} + static int sun4i_rgb_get_modes(struct drm_connector *connector) { struct sun4i_rgb *rgb =3D @@ -205,6 +210,14 @@ int sun4i_rgb_init(struct drm_device *drm, struct sun4= i_tcon *tcon) return 0; } =20 + if (rgb->panel) { + ret =3D devm_add_action_or_reset(tcon->dev, + sun4i_panel_put_action, + rgb->panel); + if (ret) + return ret; + } + drm_encoder_helper_add(&rgb->encoder, &sun4i_rgb_enc_helper_funcs); ret =3D drm_simple_encoder_init(drm, &rgb->encoder, diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i= /sun6i_mipi_dsi.c index c35b70d83e53b..1e8bc12fb6d04 100644 --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c @@ -985,6 +985,8 @@ static int sun6i_dsi_detach(struct mipi_dsi_host *host, { struct sun6i_dsi *dsi =3D host_to_sun6i_dsi(host); =20 + if (dsi->panel) + drm_panel_put(dsi->panel); dsi->panel =3D NULL; dsi->device =3D NULL; =20 diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c index 7f25c50621c94..57a016f47434d 100644 --- a/drivers/gpu/drm/tegra/dsi.c +++ b/drivers/gpu/drm/tegra/dsi.c @@ -1516,6 +1516,7 @@ static int tegra_dsi_host_detach(struct mipi_dsi_host= *host, struct tegra_output *output =3D &dsi->output; =20 if (output->panel && &device->dev =3D=3D output->panel->dev) { + drm_panel_put(output->panel); output->panel =3D NULL; =20 if (output->connector.dev) diff --git a/drivers/gpu/drm/tegra/output.c b/drivers/gpu/drm/tegra/output.c index 49e4f63a5550d..90db39dbdd332 100644 --- a/drivers/gpu/drm/tegra/output.c +++ b/drivers/gpu/drm/tegra/output.c @@ -195,6 +195,9 @@ int tegra_output_probe(struct tegra_output *output) =20 void tegra_output_remove(struct tegra_output *output) { + if (output->panel) + drm_panel_put(output->panel); + if (output->hpd_gpio) free_irq(output->hpd_irq, output); =20 --=20 2.54.0 From nobody Sat Jul 25 21:21:24 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7ED6D3EB7E5 for ; Mon, 13 Jul 2026 11:54:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; 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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260713-drm_refcount_wiring-v2-4-d3bb61f4bd4d@redhat.com> References: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> In-Reply-To: <20260713-drm_refcount_wiring-v2-0-d3bb61f4bd4d@redhat.com> To: Neil Armstrong , Jessica Zhang , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Andrzej Hajda , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Inki Dae , Jagan Teki , Marek Szyprowski , Laurentiu Palcu , Lucas Stach , Frank Li , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Paul Cercueil , Linus Walleij , Marek Vasut , Stefan Agner , Tomi Valkeinen , Laurent Pinchart , Kieran Bingham , Geert Uytterhoeven , Magnus Damm , Biju Das , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Yannick Fertre , Raphael Gallais-Pou , Philippe Cornu , Maxime Coquelin , Alexandre Torgue , Chen-Yu Tsai , Samuel Holland , Jyri Sarha , Jingoo Han , Seung-Woo Kim , Kyungmin Park , Krzysztof Kozlowski , Peter Griffin , Alim Akhtar , Alison Wang , Paul Kocialkowski , Alain Volmat , Raphael Gallais-Pou , Thierry Reding , Mikko Perttunen , Jonathan Hunter Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, linux-sunxi@lists.linux.dev, linux-samsung-soc@vger.kernel.org, linux-tegra@vger.kernel.org, Albert Esteve X-Developer-Signature: v=1; a=ed25519-sha256; t=1783943594; l=2316; i=aesteve@redhat.com; s=20260303; h=from:subject:message-id; bh=sbVH6ShKanxtA5W9Xywae/baWgVvRmbdqq4dmgcH2zU=; b=P+uXW64NeMeDz+v7ZdK9Rk/p7UzsOiF++6hDBewi6tGE7qdfB+UP54eECes9KOSS7cXXFhGxn N80BV1LxXkUCzr74V7G2Teaj6ix2xiKoAkyDXxCzT+PHAEdXFcA/Vq2 X-Developer-Key: i=aesteve@redhat.com; a=ed25519; pk=YSFz6sOHd2L45+Fr8DIvHTi6lSIjhLZ5T+rkxspJt1s= X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 find_panel_by_fwnode() is the fwnode-based counterpart to of_drm_find_panel(), used internally by drm_panel_add_follower(). Like of_drm_find_panel(), it returned an unrefcounted pointer, leaving a window where the panel could be freed between the lookup and first use. drm_panel_add_follower() worked around the missing panel kref by calling get_device() on the panel's underlying struct device. However, get_device() only prevents the device kobject from being freed. It does not prevent the panel's kzalloc()'d container memory from being released when the kref reaches zero. Apply the same fix: call drm_panel_get() under panel_lock before returning. Since find_panel_by_fwnode() now transfers a counted reference to drm_panel_add_follower(), drm_panel_remove_follower() must balance it with a matching drm_panel_put(). Signed-off-by: Albert Esteve Acked-by: Maxime Ripard --- drivers/gpu/drm/drm_panel.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 72cf86253c0cd..a00ae98ed0956 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -542,7 +542,13 @@ int of_drm_get_panel_orientation(const struct device_n= ode *np, EXPORT_SYMBOL(of_drm_get_panel_orientation); #endif =20 -/* Find panel by fwnode. This should be identical to of_drm_find_panel(). = */ +/* + * Find panel by fwnode, returning a counted reference. + * + * Behaves identically to of_drm_find_panel(). On success the returned + * pointer has been passed through drm_panel_get(); the caller must call + * drm_panel_put() when done with it. + */ static struct drm_panel *find_panel_by_fwnode(const struct fwnode_handle *= fwnode) { struct drm_panel *panel; @@ -554,6 +560,7 @@ static struct drm_panel *find_panel_by_fwnode(const str= uct fwnode_handle *fwnode =20 list_for_each_entry(panel, &panel_list, list) { if (dev_fwnode(panel->dev) =3D=3D fwnode) { + drm_panel_get(panel); mutex_unlock(&panel_lock); return panel; } @@ -690,6 +697,7 @@ void drm_panel_remove_follower(struct drm_panel_followe= r *follower) mutex_unlock(&panel->follower_lock); =20 put_device(panel->dev); + drm_panel_put(panel); } EXPORT_SYMBOL(drm_panel_remove_follower); =20 --=20 2.54.0 From nobody Sat Jul 25 21:21:24 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 680423F482A for ; 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a=ed25519-sha256; t=1783943594; l=10544; i=aesteve@redhat.com; s=20260303; h=from:subject:message-id; bh=dzpeOF7sIt4/OTXPktgi6VTN8JiIFkFsUfT9qr3ZGsc=; b=GTZrudD6UEdPrnwfxKbrh6LYnSu+4moS+csq9PLxmamwmOpey3SHrVdp4Cw1NF18XT2asYUWL /5o3jUmUMIMBF0G2HX7WJZ5BCOeYsD6p9xLxNE+1MBRYjLSN1ZCU0L1 X-Developer-Key: i=aesteve@redhat.com; a=ed25519; pk=YSFz6sOHd2L45+Fr8DIvHTi6lSIjhLZ5T+rkxspJt1s= X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Update a second batch of drivers calling of_drm_find_panel() or drm_of_find_panel_or_bridge() to release the lookup reference after wrapping the panel in a bridge. Also handle the cases where a panel is found but cannot be used, dropping the reference immediately in those paths. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Albert Esteve --- drivers/gpu/drm/imx/dcss/dcss-kms.c | 3 +++ drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 4 +++- drivers/gpu/drm/mcde/mcde_drv.c | 1 + drivers/gpu/drm/mcde/mcde_dsi.c | 1 + drivers/gpu/drm/mxsfb/mxsfb_drv.c | 1 + drivers/gpu/drm/omapdrm/dss/output.c | 1 + drivers/gpu/drm/pl111/pl111_drv.c | 1 + drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c | 1 + drivers/gpu/drm/renesas/rcar-du/rcar_lvds.c | 1 + drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c | 1 + drivers/gpu/drm/rockchip/rockchip_lvds.c | 1 + drivers/gpu/drm/rockchip/rockchip_rgb.c | 1 + drivers/gpu/drm/stm/ltdc.c | 1 + drivers/gpu/drm/sun4i/sun4i_tcon.c | 2 ++ drivers/gpu/drm/tidss/tidss_kms.c | 16 +++++++++++----- drivers/gpu/drm/tve200/tve200_drv.c | 1 + 16 files changed, 31 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/imx/dcss/dcss-kms.c b/drivers/gpu/drm/imx/dcss= /dcss-kms.c index 50bd7f36d36dd..01e0c10b6ea1a 100644 --- a/drivers/gpu/drm/imx/dcss/dcss-kms.c +++ b/drivers/gpu/drm/imx/dcss/dcss-kms.c @@ -77,6 +77,9 @@ static int dcss_kms_bridge_connector_init(struct dcss_kms= _dev *kms) if (ret) return ret; =20 + if (panel) + drm_panel_put(panel); + if (!bridge) { dev_err(ddev->dev, "No bridge found %d.\n", ret); return -ENODEV; diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/in= genic/ingenic-drm-drv.c index 42c86f195c66b..1887e01d29701 100644 --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c @@ -1297,9 +1297,11 @@ static int ingenic_drm_bind(struct device *dev, bool= has_components) goto err_drvdata; } =20 - if (panel) + if (panel) { bridge =3D devm_drm_panel_bridge_add_typed(dev, panel, DRM_MODE_CONNECTOR_DPI); + drm_panel_put(panel); + } =20 ib =3D drmm_encoder_alloc(drm, struct ingenic_drm_bridge, encoder, NULL, DRM_MODE_ENCODER_DPI, NULL); diff --git a/drivers/gpu/drm/mcde/mcde_drv.c b/drivers/gpu/drm/mcde/mcde_dr= v.c index 5f2c462bad7e1..53275b575f0cb 100644 --- a/drivers/gpu/drm/mcde/mcde_drv.c +++ b/drivers/gpu/drm/mcde/mcde_drv.c @@ -153,6 +153,7 @@ static int mcde_modeset_init(struct drm_device *drm) if (panel) { bridge =3D drm_panel_bridge_add_typed(panel, DRM_MODE_CONNECTOR_DPI); + drm_panel_put(panel); if (IS_ERR(bridge)) { dev_err(drm->dev, "Could not connect panel bridge\n"); diff --git a/drivers/gpu/drm/mcde/mcde_dsi.c b/drivers/gpu/drm/mcde/mcde_ds= i.c index 47d45897ed069..d9a454f226f79 100644 --- a/drivers/gpu/drm/mcde/mcde_dsi.c +++ b/drivers/gpu/drm/mcde/mcde_dsi.c @@ -1124,6 +1124,7 @@ static int mcde_dsi_bind(struct device *dev, struct d= evice *master, if (panel) { bridge =3D drm_panel_bridge_add_typed(panel, DRM_MODE_CONNECTOR_DSI); + drm_panel_put(panel); if (IS_ERR(bridge)) { dev_err(dev, "error adding panel bridge\n"); return PTR_ERR(bridge); diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsf= b_drv.c index 0b756da2fec22..bfcdc0c237ee1 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c @@ -128,6 +128,7 @@ static int mxsfb_attach_bridge(struct mxsfb_drm_private= *mxsfb) if (panel) { bridge =3D devm_drm_panel_bridge_add_typed(drm->dev, panel, DRM_MODE_CONNECTOR_DPI); + drm_panel_put(panel); if (IS_ERR(bridge)) return PTR_ERR(bridge); } diff --git a/drivers/gpu/drm/omapdrm/dss/output.c b/drivers/gpu/drm/omapdrm= /dss/output.c index ca891aba38209..6e9bc605ee22f 100644 --- a/drivers/gpu/drm/omapdrm/dss/output.c +++ b/drivers/gpu/drm/omapdrm/dss/output.c @@ -43,6 +43,7 @@ int omapdss_device_init_output(struct omap_dss_device *ou= t, struct drm_bridge *bridge; =20 bridge =3D drm_panel_bridge_add(out->panel); + drm_panel_put(out->panel); if (IS_ERR(bridge)) { dev_err(out->dev, "unable to create panel bridge (%ld)\n", diff --git a/drivers/gpu/drm/pl111/pl111_drv.c b/drivers/gpu/drm/pl111/pl11= 1_drv.c index ac7b1d12a0f59..8ec659b3c08eb 100644 --- a/drivers/gpu/drm/pl111/pl111_drv.c +++ b/drivers/gpu/drm/pl111/pl111_drv.c @@ -145,6 +145,7 @@ static int pl111_modeset_init(struct drm_device *dev) if (panel) { bridge =3D drm_panel_bridge_add_typed(panel, DRM_MODE_CONNECTOR_Unknown); + drm_panel_put(panel); if (IS_ERR(bridge)) { ret =3D PTR_ERR(bridge); goto finish; diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c b/drivers/gp= u/drm/renesas/rcar-du/rcar_du_encoder.c index db2088529b480..d8e7e9877ba86 100644 --- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c @@ -69,6 +69,7 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu, =20 bridge =3D devm_drm_panel_bridge_add_typed(rcdu->dev, panel, DRM_MODE_CONNECTOR_DPI); + drm_panel_put(panel); if (IS_ERR(bridge)) return PTR_ERR(no_free_ptr(bridge)); =20 diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_lvds.c b/drivers/gpu/drm/= renesas/rcar-du/rcar_lvds.c index 154410745a74b..cc2996f044721 100644 --- a/drivers/gpu/drm/renesas/rcar-du/rcar_lvds.c +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_lvds.c @@ -791,6 +791,7 @@ static int rcar_lvds_parse_dt(struct rcar_lvds *lvds) if (lvds->panel) { lvds->next_bridge =3D devm_drm_panel_bridge_add(lvds->dev, lvds->panel); + drm_panel_put(lvds->panel); if (IS_ERR_OR_NULL(lvds->next_bridge)) { ret =3D -EINVAL; goto done; diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c b/drivers/gpu= /drm/renesas/rz-du/rzg2l_du_encoder.c index f50d166b764f5..3d0999e4fcfdf 100644 --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c @@ -90,6 +90,7 @@ int rzg2l_du_encoder_init(struct rzg2l_du_device *rcdu, =20 bridge =3D devm_drm_panel_bridge_add_typed(rcdu->dev, panel, DRM_MODE_CONNECTOR_DPI); + drm_panel_put(panel); if (IS_ERR(bridge)) return PTR_ERR(no_free_ptr(bridge)); =20 diff --git a/drivers/gpu/drm/rockchip/rockchip_lvds.c b/drivers/gpu/drm/roc= kchip/rockchip_lvds.c index 7a0c4fa29f2f0..f754445d2631b 100644 --- a/drivers/gpu/drm/rockchip/rockchip_lvds.c +++ b/drivers/gpu/drm/rockchip/rockchip_lvds.c @@ -605,6 +605,7 @@ static int rockchip_lvds_bind(struct device *dev, struc= t device *master, =20 if (lvds->panel) { lvds->bridge =3D drm_panel_bridge_add_typed(lvds->panel, DRM_MODE_CONNEC= TOR_LVDS); + drm_panel_put(lvds->panel); if (IS_ERR(lvds->bridge)) { ret =3D PTR_ERR(lvds->bridge); goto err_free_encoder; diff --git a/drivers/gpu/drm/rockchip/rockchip_rgb.c b/drivers/gpu/drm/rock= chip/rockchip_rgb.c index add3123e5ce70..ea66c70013787 100644 --- a/drivers/gpu/drm/rockchip/rockchip_rgb.c +++ b/drivers/gpu/drm/rockchip/rockchip_rgb.c @@ -139,6 +139,7 @@ struct rockchip_rgb *rockchip_rgb_init(struct device *d= ev, if (panel) { bridge =3D drm_panel_bridge_add_typed(panel, DRM_MODE_CONNECTOR_LVDS); + drm_panel_put(panel); if (IS_ERR(bridge)) return ERR_CAST(bridge); } diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 95fcfa48d8be3..daf198edb42f5 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -1982,6 +1982,7 @@ int ltdc_load(struct drm_device *ddev) =20 if (panel) { bridge =3D drmm_panel_bridge_add(ddev, panel); + drm_panel_put(panel); if (IS_ERR(bridge)) { drm_err(ddev, "panel-bridge endpoint %d\n", i); ret =3D PTR_ERR(bridge); diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun= 4i_tcon.c index 960e83c8291da..d4c1723c5e3d8 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -1326,6 +1326,8 @@ static int sun4i_tcon_probe(struct platform_device *p= dev) ret =3D drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge); if (ret =3D=3D -EPROBE_DEFER) return ret; + if (panel) + drm_panel_put(panel); } =20 return component_add(&pdev->dev, &sun4i_tcon_ops); diff --git a/drivers/gpu/drm/tidss/tidss_kms.c b/drivers/gpu/drm/tidss/tids= s_kms.c index 1512ee2574b66..70c14c3be10d5 100644 --- a/drivers/gpu/drm/tidss/tidss_kms.c +++ b/drivers/gpu/drm/tidss/tidss_kms.c @@ -162,6 +162,7 @@ static int tidss_dispc_modeset_init(struct tidss_device= *tidss) =20 if (panel) { u32 conn_type; + int ret; =20 dev_dbg(dev, "Setting up panel for port %d\n", i); =20 @@ -176,7 +177,8 @@ static int tidss_dispc_modeset_init(struct tidss_device= *tidss) break; default: WARN_ON(1); - return -EINVAL; + ret =3D -EINVAL; + goto put_panel; } =20 if (panel->connector_type !=3D conn_type) { @@ -184,16 +186,20 @@ static int tidss_dispc_modeset_init(struct tidss_devi= ce *tidss) "%s: Panel %s has incompatible connector type for vp%d (%d !=3D %d)\n= ", __func__, dev_name(panel->dev), i, panel->connector_type, conn_type); - return -EINVAL; + ret =3D -EINVAL; + goto put_panel; } =20 bridge =3D devm_drm_panel_bridge_add(dev, panel); - if (IS_ERR(bridge)) { + ret =3D PTR_ERR_OR_ZERO(bridge); + if (ret) dev_err(dev, "failed to set up panel bridge for port %d\n", i); - return PTR_ERR(bridge); - } +put_panel: + drm_panel_put(panel); + if (ret) + return ret; } =20 pipes[num_pipes].hw_videoport =3D i; diff --git a/drivers/gpu/drm/tve200/tve200_drv.c b/drivers/gpu/drm/tve200/t= ve200_drv.c index 562f3f11812a3..f858c58ccb994 100644 --- a/drivers/gpu/drm/tve200/tve200_drv.c +++ b/drivers/gpu/drm/tve200/tve200_drv.c @@ -84,6 +84,7 @@ static int tve200_modeset_init(struct drm_device *dev) if (panel) { bridge =3D drm_panel_bridge_add_typed(panel, DRM_MODE_CONNECTOR_Unknown); + drm_panel_put(panel); if (IS_ERR(bridge)) { ret =3D PTR_ERR(bridge); goto out_bridge; --=20 2.54.0