This is a note to let you know that I've just added the patch titled
[PATCH 6.1.y] drm/amd/display: Don't refer to dc_sink in is_dsc_need_re_compute to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-don-t-refer-to-dc_sink-in-is_dsc_need_re_compute.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <sta...@vger.kernel.org> know about it. >From jianqi.ren...@windriver.com Thu Dec 12 13:11:21 2024 From: <jianqi.ren...@windriver.com> Date: Wed, 11 Dec 2024 18:15:44 +0800 Subject: [PATCH 6.1.y] drm/amd/display: Don't refer to dc_sink in is_dsc_need_re_compute To: <wayne....@amd.com>, <gre...@linuxfoundation.org> Cc: <patc...@lists.linux.dev>, <jerry....@amd.com>, <zaeem.moha...@amd.com>, <daniel.whee...@amd.com>, <alexander.deuc...@amd.com>, <sta...@vger.kernel.org>, <harry.wentl...@amd.com>, <sunpeng...@amd.com>, <rodrigo.sique...@amd.com>, <christian.koe...@amd.com>, <airl...@gmail.com>, <dan...@ffwll.ch>, <jerry....@amd.com>, <amd-gfx@lists.freedesktop.org>, <dri-de...@lists.freedesktop.org>, <linux-ker...@vger.kernel.org> Message-ID: <20241211101544.2121147-1-jianqi.ren...@windriver.com> From: Wayne Lin <wayne....@amd.com> [ Upstream commit fcf6a49d79923a234844b8efe830a61f3f0584e4 ] [Why] When unplug one of monitors connected after mst hub, encounter null pointer dereference. It's due to dc_sink get released immediately in early_unregister() or detect_ctx(). When commit new state which directly referring to info stored in dc_sink will cause null pointer dereference. [how] Remove redundant checking condition. Relevant condition should already be covered by checking if dsc_aux is null or not. Also reset dsc_aux to NULL when the connector is disconnected. Reviewed-by: Jerry Zuo <jerry....@amd.com> Acked-by: Zaeem Mohamed <zaeem.moha...@amd.com> Signed-off-by: Wayne Lin <wayne....@amd.com> Tested-by: Daniel Wheeler <daniel.whee...@amd.com> Signed-off-by: Alex Deucher <alexander.deuc...@amd.com> Signed-off-by: Jianqi Ren <jianqi.ren...@windriver.com> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 1acef5f3838f..a1619f4569cf 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -183,6 +183,8 @@ amdgpu_dm_mst_connector_early_unregister(struct drm_connector *connector) dc_sink_release(dc_sink); aconnector->dc_sink = NULL; aconnector->edid = NULL; + aconnector->dsc_aux = NULL; + port->passthrough_aux = NULL; } aconnector->mst_status = MST_STATUS_DEFAULT; @@ -487,6 +489,8 @@ dm_dp_mst_detect(struct drm_connector *connector, dc_sink_release(aconnector->dc_sink); aconnector->dc_sink = NULL; aconnector->edid = NULL; + aconnector->dsc_aux = NULL; + port->passthrough_aux = NULL; amdgpu_dm_set_mst_status(&aconnector->mst_status, MST_REMOTE_EDID | MST_ALLOCATE_NEW_PAYLOAD | MST_CLEAR_ALLOCATED_PAYLOAD, -- 2.25.1 Patches currently in stable-queue which might be from jianqi.ren...@windriver.com are queue-5.4/drm-amd-display-don-t-refer-to-dc_sink-in-is_dsc_need_re_compute.patch