diff mbox

[v9,5/5] drm/bridge/synopsys: dw-hdmi: Add missing bridge detach

Message ID 20180302175757.28192-6-enric.balletbo@collabora.com (mailing list archive)
State New, archived
Headers show

Commit Message

Enric Balletbo i Serra March 2, 2018, 5:57 p.m. UTC
From: Jeffy Chen <jeffy.chen@rock-chips.com>

We inited connector in attach(), so need a detach() to cleanup.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
---

Changes in v9: None

 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Jeffy Chen March 5, 2018, 7:01 a.m. UTC | #1
Hi Laurent,

sorry, you're right, this patch should not be needed.

the connector should be cleanup by 
drm_mode_config_cleanup->drm_connector_put.

i did that in analogix_dp is to avoid a use-after-free issue not 
kmemleak, because the connector was allocated/freed in analogix_dp's 
bind/unbind.

but i found a kmemleak issue(dma_mask not freed) in dw-hdmi when testing 
that, will send patch soon.

On 03/03/2018 08:20 AM, JeffyChen wrote:
> Hi Laurent,
>
> On 03/03/2018 05:49 AM, Laurent Pinchart wrote:
>> Hi Enric,
>>
>> Thank you for the patch.
>>
>> On Friday, 2 March 2018 19:57:57 EET Enric Balletbo i Serra wrote:
>>> From: Jeffy Chen <jeffy.chen@rock-chips.com>
>>>
>>> We inited connector in attach(), so need a detach() to cleanup.
>>
>> Do we ? The dw-hdmi driver already sets drm_connector_cleanup() as the
>> connector .destroy() handler, and the .destroy() operation is called
>> by the
>> DRM core. None of the other bridge drivers call drm_connector_cleanup()
>> directly.
>
> hmmm, checking the code, there are also lots of drivers do the
> cleanup(drm_connector_cleanup or funcs->destroy):
> drm# grep -r "connector.*funcs->destroy" .
> ./rockchip/inno_hdmi.c: hdmi->connector.funcs->destroy(&hdmi->connector);
> ./rockchip/cdn-dp-core.c:       connector->funcs->destroy(connector);
> ./bridge/analogix/analogix_dp_core.c:
> dp->connector.funcs->destroy(&dp->connector);
> ./msm/hdmi/hdmi.c: hdmi->connector->funcs->destroy(hdmi->connector);
> ./msm/dsi/dsi.c: msm_dsi->connector->funcs->destroy(msm_dsi->connector);
> ./msm/edp/edp.c: edp->connector->funcs->destroy(edp->connector);
> ./zte/zx_hdmi.c:        hdmi->connector.funcs->destroy(&hdmi->connector);
> ./drm_connector.c:      connector->funcs->destroy(connector);
> ./drm_connector.c:              connector->funcs->destroy(connector);
> ./nouveau/dispnv04/disp.c: connector->funcs->destroy(connector);
> ./nouveau/nv50_display.c: mstc->connector.funcs->destroy(&mstc->connector);
> ./nouveau/nv50_display.c: connector->funcs->destroy(connector);
>
>
>
> when i debug analogix_dp bind/unbind, i found that we need to cleanup
> the connector(reported by kmemleak). so i added it to
> ./bridge/analogix/analogix_dp_core.c...after that i saw dw-hdmi missing
> that too(by checking the code), so make this patch.
>
> but i didn't really tested it on devices using dw-hdmi, so i'm not very
> sure the dw-hdmi(maybe also other bridges) is the same with analogix_dp.
>
> i can try to find a chromebook veyron to check it next week :)
>
> but even there's a leak, i'm still not very sure about:
> should the caller of drm_connector_init cleanup it
> or the caller of drm_bridge_attach should do it(for example
> analogix_dp_bind/analogix_dp_unbind)
> or should the DRM core take care of that?
>
>>
>>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>>> Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
>>> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
>>> ---
diff mbox

Patch

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index f9802399cc0d..5626922f95f9 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -1985,6 +1985,13 @@  static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
 	return 0;
 }
 
+static void dw_hdmi_bridge_detach(struct drm_bridge *bridge)
+{
+	struct dw_hdmi *hdmi = bridge->driver_private;
+
+	drm_connector_cleanup(&hdmi->connector);
+}
+
 static enum drm_mode_status
 dw_hdmi_bridge_mode_valid(struct drm_bridge *bridge,
 			  const struct drm_display_mode *mode)
@@ -2041,6 +2048,7 @@  static void dw_hdmi_bridge_enable(struct drm_bridge *bridge)
 
 static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = {
 	.attach = dw_hdmi_bridge_attach,
+	.detach = dw_hdmi_bridge_detach,
 	.enable = dw_hdmi_bridge_enable,
 	.disable = dw_hdmi_bridge_disable,
 	.mode_set = dw_hdmi_bridge_mode_set,