From de9f8eea5a44b0b756d3d6345af7f8e630a3c8c0 Mon Sep 17 00:00:00 2001 From: Lyude Paul Date: Tue, 16 Oct 2018 16:39:46 -0400 Subject: drm/atomic_helper: Stop modesets on unregistered connectors harder MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Unfortunately, it appears our fix in: commit b5d29843d8ef ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Which attempted to work around the problems introduced by: commit 4d80273976bf ("drm/atomic_helper: Disallow new modesets on unregistered connectors") Is still not the right solution, as modesets can still be triggered outside of drm_atomic_set_crtc_for_connector(). So in order to fix this, while still being careful that we don't break modesets that a driver may perform before being registered with userspace, we replace connector->registered with a tristate member, connector->registration_state. This allows us to keep track of whether or not a connector is still initializing and hasn't been exposed to userspace, is currently registered and exposed to userspace, or has been legitimately removed from the system after having once been present. Using this info, we can prevent userspace from performing new modesets on unregistered connectors while still allowing the driver to perform modesets on unregistered connectors before the driver has finished being registered. Changes since v1: - Fix WARN_ON() in drm_connector_cleanup() that CI caught with this patchset in igt@drv_module_reload@basic-reload-inject and igt@drv_module_reload@basic-reload by checking if the connector is registered instead of unregistered, as calling drm_connector_cleanup() on a connector that hasn't been registered with userspace yet should stay valid. - Remove unregistered_connector_check(), and just go back to what we were doing before in commit 4d80273976bf ("drm/atomic_helper: Disallow new modesets on unregistered connectors") except replacing READ_ONCE(connector->registered) with drm_connector_is_unregistered(). This gets rid of the behavior of allowing DPMS On<->Off, but that should be fine as it's more consistent with the UAPI we had before - danvet - s/drm_connector_unregistered/drm_connector_is_unregistered/ - danvet - Update documentation, fix some typos. Fixes: b5d29843d8ef ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Cc: Ville Syrjälä Cc: Daniel Vetter Cc: Rodrigo Vivi Cc: stable@vger.kernel.org Cc: David Airlie Signed-off-by: Lyude Paul Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20181016203946.9601-1-lyude@redhat.com (cherry picked from commit 39b50c603878f4f8ae541ac4088a805d588abc79) Fixes: e96550956fbc ("drm/atomic_helper: Disallow new modesets on unregistered connectors") Fixes: 34ca26a98ad6 ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Cc: stable@vger.kernel.org Signed-off-by: Joonas Lahtinen --- drivers/gpu/drm/i915/intel_dp_mst.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/gpu/drm/i915/intel_dp_mst.c') diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index 7f155b4f1a7d..1b00f8ea145b 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -77,7 +77,7 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder, pipe_config->pbn = mst_pbn; /* Zombie connectors can't have VCPI slots */ - if (READ_ONCE(connector->registered)) { + if (!drm_connector_is_unregistered(connector)) { slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr, port, @@ -313,7 +313,7 @@ static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector) struct edid *edid; int ret; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return intel_connector_update_modes(connector, NULL); edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -329,7 +329,7 @@ intel_dp_mst_detect(struct drm_connector *connector, bool force) struct intel_connector *intel_connector = to_intel_connector(connector); struct intel_dp *intel_dp = intel_connector->mst_port; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return connector_status_disconnected; return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -372,7 +372,7 @@ intel_dp_mst_mode_valid(struct drm_connector *connector, int bpp = 24; /* MST uses fixed bpp */ int max_rate, mode_rate, max_lanes, max_link_clock; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return MODE_ERROR; if (mode->flags & DRM_MODE_FLAG_DBLSCAN) -- cgit v1.2.3