From: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
We enable the DP aux channel during probe, but may free the connector
soon afterwards. Ensure the DP aux display power put is completed before
everything is freed, to prevent a use-after-free in icl_aux_pw_to_phy(),
called from icl_combo_phy_aux_power_well_disable.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_display_power.c | 2 +-
drivers/gpu/drm/i915/display/intel_display_power.h | 1 +
drivers/gpu/drm/i915/display/intel_dp_aux.c | 2 ++
3 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index fd0fedb65e42..cdb36e3f96cd 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -786,7 +786,7 @@ void intel_display_power_flush_work(struct drm_i915_private *i915)
* Like intel_display_power_flush_work(), but also ensure that the work
* handler function is not running any more when this function returns.
*/
-static void
+void
intel_display_power_flush_work_sync(struct drm_i915_private *i915)
{
struct i915_power_domains *power_domains = &i915->display.power.domains;
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.h b/drivers/gpu/drm/i915/display/intel_display_power.h
index 2154d900b1aa..d220f6b16e00 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.h
+++ b/drivers/gpu/drm/i915/display/intel_display_power.h
@@ -195,6 +195,7 @@ void __intel_display_power_put_async(struct drm_i915_private *i915,
enum intel_display_power_domain domain,
intel_wakeref_t wakeref);
void intel_display_power_flush_work(struct drm_i915_private *i915);
+void intel_display_power_flush_work_sync(struct drm_i915_private *i915);
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
void intel_display_power_put(struct drm_i915_private *dev_priv,
enum intel_display_power_domain domain,
diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux.c b/drivers/gpu/drm/i915/display/intel_dp_aux.c
index 91c93c93e5fc..220aa88c67ee 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_aux.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_aux.c
@@ -680,6 +680,8 @@ void intel_dp_aux_fini(struct intel_dp *intel_dp)
if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
cpu_latency_qos_remove_request(&intel_dp->pm_qos);
+ /* Ensure async work from intel_dp_aux_xfer() is flushed before we clean up */
+ intel_display_power_flush_work_sync(dp_to_i915(intel_dp));
kfree(intel_dp->aux.name);
}
--
2.37.3
