4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Archit Taneja <architt@xxxxxxxxxxxxxx> [ Upstream commit 9dcfbc182f1aac0aa5ea194733d21e67dd2ba1fd ] The msm/kms driver should work even if there is no GPU device specified in DT. Currently, we get a NULL dereference crash in adreno_load_gpu since the driver assumes that priv->gpu_pdev is non-NULL. Perform an additional check on priv->gpu_pdev before trying to retrieve the msm_gpu pointer from it. v2: Incorporate Jordan's comments: - Simplify the check to share the same error message. - Use dev_err_once() to avoid an error message every time we open the drm device fd. Fixes: eec874ce5ff1 (drm/msm/adreno: load gpu at probe/bind time) Signed-off-by: Archit Taneja <architt@xxxxxxxxxxxxxx> Acked-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx> Signed-off-by: Rob Clark <robdclark@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/msm/adreno/adreno_device.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/msm/adreno/adreno_device.c +++ b/drivers/gpu/drm/msm/adreno/adreno_device.c @@ -125,11 +125,14 @@ struct msm_gpu *adreno_load_gpu(struct d { struct msm_drm_private *priv = dev->dev_private; struct platform_device *pdev = priv->gpu_pdev; - struct msm_gpu *gpu = platform_get_drvdata(priv->gpu_pdev); + struct msm_gpu *gpu = NULL; int ret; + if (pdev) + gpu = platform_get_drvdata(pdev); + if (!gpu) { - dev_err(dev->dev, "no adreno device\n"); + dev_err_once(dev->dev, "no GPU device was found\n"); return NULL; }