4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lyude Paul <lyude@xxxxxxxxxx> commit b89fdf7ae8500feae1100d8b283176a44d31d698 upstream. We need to actually make sure we check this on resume since otherwise we won't know whether or not the topology is still there once we've resumed, which will cause us to still think the topology is connected even after it's been removed if the removal happens mid-suspend. Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ben Skeggs <bskeggs@xxxxxxxxxx> Signed-off-by: Ben Skeggs <bskeggs@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/nouveau/dispnv50/disp.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/nouveau/dispnv50/disp.c +++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c @@ -1224,8 +1224,16 @@ nv50_mstm_fini(struct nv50_mstm *mstm) static void nv50_mstm_init(struct nv50_mstm *mstm) { - if (mstm && mstm->mgr.mst_state) - drm_dp_mst_topology_mgr_resume(&mstm->mgr); + int ret; + + if (!mstm || !mstm->mgr.mst_state) + return; + + ret = drm_dp_mst_topology_mgr_resume(&mstm->mgr); + if (ret == -1) { + drm_dp_mst_topology_mgr_set_mst(&mstm->mgr, false); + drm_kms_helper_hotplug_event(mstm->mgr.dev); + } } static void