From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Date: Fri, 6 Dec 2024 09:43:09 +0000 (+0200)
Subject: drm/i915/audio: use eld_mutex to protect access to connector->eld
X-Git-Tag: v6.14-rc1~174^2~13^2~45
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5db44dd1528625c73a31542df2a68972327c9897;p=thirdparty%2Fkernel%2Flinux.git

drm/i915/audio: use eld_mutex to protect access to connector->eld

Reading access to connector->eld can happen at the same time the
drm_edid_to_eld() updates the data. Take the newly added eld_mutex in
order to protect connector->eld from concurrent access.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241206-drm-connector-eld-mutex-v2-6-c9bce1ee8bea@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---

diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c
index 32aa9ec1a204d..3902ab8431139 100644
--- a/drivers/gpu/drm/i915/display/intel_audio.c
+++ b/drivers/gpu/drm/i915/display/intel_audio.c
@@ -699,10 +699,12 @@ bool intel_audio_compute_config(struct intel_encoder *encoder,
 	const struct drm_display_mode *adjusted_mode =
 		&crtc_state->hw.adjusted_mode;
 
+	mutex_lock(&connector->eld_mutex);
 	if (!connector->eld[0]) {
 		drm_dbg_kms(&i915->drm,
 			    "Bogus ELD on [CONNECTOR:%d:%s]\n",
 			    connector->base.id, connector->name);
+		mutex_unlock(&connector->eld_mutex);
 		return false;
 	}
 
@@ -710,6 +712,7 @@ bool intel_audio_compute_config(struct intel_encoder *encoder,
 	memcpy(crtc_state->eld, connector->eld, sizeof(crtc_state->eld));
 
 	crtc_state->eld[6] = drm_av_sync_delay(connector, adjusted_mode) / 2;
+	mutex_unlock(&connector->eld_mutex);
 
 	return true;
 }