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.c...@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.c...@rock-chips.com>
Signed-off-by: Thierry Escande <thierry.esca...@collabora.com>
Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com>
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