[PATCH AUTOSEL 6.0 01/30] drm/msm/gpu: Fix crash during system suspend after unbind

[Sasha Levin <sashal@kernel.org>]

From: Akhil P Oommen <quic_akhilpo@quicinc.com>

[ Upstream commit 76efc2453d0e8e5d6692ef69981b183ad674edea ]

In adreno_unbind, we should clean up gpu device's drvdata to avoid
accessing a stale pointer during system suspend. Also, check for NULL
ptr in both system suspend/resume callbacks.

Signed-off-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/505075/
Link: https://lore.kernel.org/r/20220928124830.2.I5ee0ac073ccdeb81961e5ec0cce5f741a7207a71@changeid
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/msm/adreno/adreno_device.c | 10 +++++++++-
 drivers/gpu/drm/msm/msm_gpu.c              |  2 ++
 drivers/gpu/drm/msm/msm_gpu.h              |  4 ++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm/msm/adreno/adreno_device.c
index 24b489b6129a..628806423f7d 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_device.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
@@ -679,6 +679,9 @@ static int adreno_system_suspend(struct device *dev)
 	struct msm_gpu *gpu = dev_to_gpu(dev);
 	int remaining, ret;
 
+	if (!gpu)
+		return 0;
+
 	suspend_scheduler(gpu);
 
 	remaining = wait_event_timeout(gpu->retire_event,
@@ -700,7 +703,12 @@ static int adreno_system_suspend(struct device *dev)
 
 static int adreno_system_resume(struct device *dev)
 {
-	resume_scheduler(dev_to_gpu(dev));
+	struct msm_gpu *gpu = dev_to_gpu(dev);
+
+	if (!gpu)
+		return 0;
+
+	resume_scheduler(gpu);
 	return pm_runtime_force_resume(dev);
 }
 
diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index c2bfcf3f1f40..01aae792ffa9 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -993,4 +993,6 @@ void msm_gpu_cleanup(struct msm_gpu *gpu)
 	}
 
 	msm_devfreq_cleanup(gpu);
+
+	platform_set_drvdata(gpu->pdev, NULL);
 }
diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h
index 4d935fedd2ac..fd22cf4041af 100644
--- a/drivers/gpu/drm/msm/msm_gpu.h
+++ b/drivers/gpu/drm/msm/msm_gpu.h
@@ -282,6 +282,10 @@ struct msm_gpu {
 static inline struct msm_gpu *dev_to_gpu(struct device *dev)
 {
 	struct adreno_smmu_priv *adreno_smmu = dev_get_drvdata(dev);
+
+	if (!adreno_smmu)
+		return NULL;
+
 	return container_of(adreno_smmu, struct msm_gpu, adreno_smmu);
 }
 
-- 
2.35.1