diff options
| author | AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> | 2025-04-03 12:47:38 +0200 |
|---|---|---|
| committer | Chun-Kuang Hu <chunkuang.hu@kernel.org> | 2025-05-14 23:06:24 +0000 |
| commit | 80805b62ea5b95eda54c225b989f929ca0691ab0 (patch) | |
| tree | b0d0b86228791ce9ecda2881134fdf1e46ba1118 | |
| parent | 22918591fb747a6d16801e74a170cf98e886f83b (diff) | |
drm/mediatek: Fix kobject put for component sub-drivers
In function mtk_drm_get_all_drm_priv(), this driver is incrementing
the refcount for the sub-drivers of mediatek-drm with a call to
device_find_child() when taking a reference to all of those child
devices.
When the component bind fails multiple times this results in a
refcount_t overflow, as the reference count is never decremented:
fix that by adding a call to put_device() for all of the mmsys
devices in a loop, in error cases of mtk_drm_bind() and in the
mtk_drm_unbind() callback.
Fixes: 1ef7ed48356c ("drm/mediatek: Modify mediatek-drm for mt8195 multi mmsys support")
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20250403104741.71045-3-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
| -rw-r--r-- | drivers/gpu/drm/mediatek/mtk_drm_drv.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 5994e2a97dc1..593193555c07 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -682,6 +682,10 @@ err_free: for (i = 0; i < private->data->mmsys_dev_num; i++) private->all_drm_private[i]->drm = NULL; err_put_dev: + for (i = 0; i < private->data->mmsys_dev_num; i++) { + /* For device_find_child in mtk_drm_get_all_priv() */ + put_device(private->all_drm_private[i]->dev); + } put_device(private->mutex_dev); return ret; } @@ -689,6 +693,7 @@ err_put_dev: static void mtk_drm_unbind(struct device *dev) { struct mtk_drm_private *private = dev_get_drvdata(dev); + int i; /* for multi mmsys dev, unregister drm dev in mmsys master */ if (private->drm_master) { @@ -696,6 +701,10 @@ static void mtk_drm_unbind(struct device *dev) mtk_drm_kms_deinit(private->drm); drm_dev_put(private->drm); + for (i = 0; i < private->data->mmsys_dev_num; i++) { + /* For device_find_child in mtk_drm_get_all_priv() */ + put_device(private->all_drm_private[i]->dev); + } put_device(private->mutex_dev); } private->mtk_drm_bound = false; |