@@ -933,6 +933,9 @@ static int intel_crt_get_modes(struct drm_connector *connector)
struct i2c_adapter *ddc;
int ret;
+ if (!intel_display_driver_check_access(dev_priv))
+ return drm_edid_connector_add_modes(connector);
+
wakeref = intel_display_power_get(dev_priv,
intel_encoder->power_domain);
@@ -1197,6 +1197,7 @@ static bool intel_dp_mst_initial_fastset_check(struct intel_encoder *encoder,
static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
{
struct intel_connector *intel_connector = to_intel_connector(connector);
+ struct drm_i915_private *i915 = to_i915(intel_connector->base.dev);
struct intel_dp *intel_dp = intel_connector->mst_port;
const struct drm_edid *drm_edid;
int ret;
@@ -1204,6 +1205,9 @@ static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
if (drm_connector_is_unregistered(connector))
return intel_connector_update_modes(connector, NULL);
+ if (!intel_display_driver_check_access(i915))
+ return drm_edid_connector_add_modes(connector);
+
drm_edid = drm_dp_mst_edid_read(connector, &intel_dp->mst_mgr, intel_connector->port);
ret = intel_connector_update_modes(connector, drm_edid);
@@ -30,6 +30,7 @@
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc.h>
+#include <drm/drm_edid.h>
#include "i915_drv.h"
#include "i915_reg.h"
@@ -338,8 +339,12 @@ intel_dvo_detect(struct drm_connector *_connector, bool force)
static int intel_dvo_get_modes(struct drm_connector *_connector)
{
struct intel_connector *connector = to_intel_connector(_connector);
+ struct drm_i915_private *i915 = to_i915(connector->base.dev);
int num_modes;
+ if (!intel_display_driver_check_access(i915))
+ return drm_edid_connector_add_modes(&connector->base);
+
/*
* We should probably have an i2c driver get_modes function for those
* devices which will have a fixed set of modes determined by the chip
@@ -2202,12 +2202,16 @@ intel_sdvo_detect(struct drm_connector *connector, bool force)
static int intel_sdvo_get_ddc_modes(struct drm_connector *connector)
{
+ struct drm_i915_private *i915 = to_i915(connector->dev);
int num_modes = 0;
const struct drm_edid *drm_edid;
drm_dbg_kms(connector->dev, "[CONNECTOR:%d:%s]\n",
connector->base.id, connector->name);
+ if (!intel_display_driver_check_access(i915))
+ return drm_edid_connector_add_modes(connector);
+
/* set the bus switch and get the modes */
drm_edid = intel_sdvo_get_edid(connector);
Prevent accessing the HW from the get_modes hooks of connectors deriving the mode list from the display's EDID. drm_edid_connector_add_modes() will return the mode list based on the EDID which was cached during a previous detection/get_modes call. This also fixes the NULL deref problem (10085) which was introduced/revealed by commit bab87ef4db9a ("drm/i915: Disable hotplug detection handlers during driver init/shutdown") After the above change MST connectors will not change state during driver init/shutdown; thus some of these connectors with no I2C/DDC adapter registered for them (since the given MST port has no sink connected) may stay then in the 'unknown' connector status. The get_modes() hook should not try to use the I2C/DDC adapter in this state (which would lead to the above NULL deref) which this patch ensures. v2: - Remove the redundant check from intel_crt_ddc_get_modes(). - Rebase on latest drm-tip. - Add Fixes: line / related commit notes. Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10085 Fixes: bab87ef4db9a ("drm/i915: Disable hotplug detection handlers during driver init/shutdown") Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Jouni Högander <jouni.hogander@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240206153910.1758057-3-imre.deak@intel.com --- drivers/gpu/drm/i915/display/intel_crt.c | 3 +++ drivers/gpu/drm/i915/display/intel_dp_mst.c | 4 ++++ drivers/gpu/drm/i915/display/intel_dvo.c | 5 +++++ drivers/gpu/drm/i915/display/intel_sdvo.c | 4 ++++ 4 files changed, 16 insertions(+)