From 21e1953b61abae4911c32c457c1d87530e622610 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Sun, 29 Dec 2019 10:55:16 +0100 Subject: backend/drm: don't modeset with a NULL mode after TTY switch This fixes a segfault in drm_connector_set_mode (mode = NULL). This happens because we set wlr_output.enabled to true if the connector is attached to the CRTC. When the user disables an output in the wlroots-based compositor, switches to another VT (enabling the output), then switches back, wlroots sets wlr_output.enabled to true but wlr_output.current_mode is NULL. We should consider not reading properties from KMS after a TTY switch, disabling all connectors. However this may result in flickering (outputs being disabled then re-enabled). Closes: https://github.com/swaywm/wlroots/issues/1874 --- backend/drm/backend.c | 2 +- backend/drm/drm.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/backend/drm/backend.c b/backend/drm/backend.c index 8a10a51e..a58af02c 100644 --- a/backend/drm/backend.c +++ b/backend/drm/backend.c @@ -93,7 +93,7 @@ static void session_signal(struct wl_listener *listener, void *data) { struct wlr_drm_connector *conn; wl_list_for_each(conn, &drm->outputs, link){ - if (conn->output.enabled) { + if (conn->output.enabled && conn->output.current_mode != NULL) { drm_connector_set_mode(&conn->output, conn->output.current_mode); } else { diff --git a/backend/drm/drm.c b/backend/drm/drm.c index e6b99bee..60f8ecaa 100644 --- a/backend/drm/drm.c +++ b/backend/drm/drm.c @@ -1439,6 +1439,8 @@ void scan_drm_connectors(struct wlr_drm_backend *drm) { wlr_conn->output.name); } + // TODO: this results in connectors being enabled without a mode + // set wlr_output_update_enabled(&wlr_conn->output, wlr_conn->crtc != NULL); wlr_conn->desired_enabled = true; -- cgit v1.2.3