6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tobias Jakobi <tjakobi@xxxxxxxxxxxxxxxxxxxxx> [ Upstream commit e7d4e1438533abe448813bdc45691f9c230aa307 ] As set_drr() is called from IRQ context, it can happen that the pipe context has been nulled by dc_state_destruct(). Apply the same protection here that is already present for dcn35_set_drr() and dcn10_set_drr(). I.e. fetch the tg pointer first (to avoid a race with dc_state_destruct()), and then check the local copy before using it. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3142 Fixes: 06ad7e164256 ("drm/amd/display: Destroy DC context while keeping DML and DML2") Acked-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Tobias Jakobi <tjakobi@xxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../amd/display/dc/hwss/dce110/dce110_hwseq.c | 21 ++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c index e9e9f80a02a77..542d669bf5e30 100644 --- a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c @@ -2020,13 +2020,20 @@ static void set_drr(struct pipe_ctx **pipe_ctx, * as well. */ for (i = 0; i < num_pipes; i++) { - pipe_ctx[i]->stream_res.tg->funcs->set_drr( - pipe_ctx[i]->stream_res.tg, ¶ms); - - if (adjust.v_total_max != 0 && adjust.v_total_min != 0) - pipe_ctx[i]->stream_res.tg->funcs->set_static_screen_control( - pipe_ctx[i]->stream_res.tg, - event_triggers, num_frames); + /* dc_state_destruct() might null the stream resources, so fetch tg + * here first to avoid a race condition. The lifetime of the pointee + * itself (the timing_generator object) is not a problem here. + */ + struct timing_generator *tg = pipe_ctx[i]->stream_res.tg; + + if ((tg != NULL) && tg->funcs) { + if (tg->funcs->set_drr) + tg->funcs->set_drr(tg, ¶ms); + if (adjust.v_total_max != 0 && adjust.v_total_min != 0) + if (tg->funcs->set_static_screen_control) + tg->funcs->set_static_screen_control( + tg, event_triggers, num_frames); + } } } -- 2.43.0
