On Tue, 2025-10-07 at 11:43 +0200, Johan Hovold wrote:
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>
> Make sure to drop the references taken to the larb devices during
> probe on probe failure (e.g. probe deferral) and on driver unbind.
>
> Note that commit 26593928564c ("iommu/mediatek: Add error path for
> loop
> of mm_dts_parse") fixed the leaks in a couple of error paths, but the
> references are still leaking on success and late failures.
>
> Fixes: 0df4fabe208d ("iommu/mediatek: Add mt8173 IOMMU driver")
> Cc: stable@vger.kernel.org # 4.6
> Cc: Yong Wu <yong.wu@mediatek.com>
> Acked-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>
> ---
> drivers/iommu/mtk_iommu.c | 24 ++++++++++++++++++------
> 1 file changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index 8d8e85186188..20a5ba80f983 100644
> --- a/drivers/iommu/mtk_iommu.c
> +++ b/drivers/iommu/mtk_iommu.c
> @@ -1216,13 +1216,17 @@ static int mtk_iommu_mm_dts_parse(struct
> device *dev, struct component_match **m
> platform_device_put(plarbdev);
> }
>
> - if (!frst_avail_smicomm_node)
> - return -EINVAL;
> + if (!frst_avail_smicomm_node) {
> + ret = -EINVAL;
> + goto err_larbdev_put;
There already is a "platform_device_put(plarbdev);" at the end of "for"
loop, then no need put_device for it outside the "for" loop or outside
this function?
Thanks.
> + }
>
> pcommdev = of_find_device_by_node(frst_avail_smicomm_node);
> of_node_put(frst_avail_smicomm_node);
> - if (!pcommdev)
> - return -ENODEV;
> + if (!pcommdev) {
> + ret = -ENODEV;
> + goto err_larbdev_put;
> + }
> data->smicomm_dev = &pcommdev->dev;
>
> link = device_link_add(data->smicomm_dev, dev,
> @@ -1230,7 +1234,8 @@ static int mtk_iommu_mm_dts_parse(struct device
> *dev, struct component_match **m
> platform_device_put(pcommdev);
> if (!link) {
> dev_err(dev, "Unable to link %s.\n", dev_name(data-
> >smicomm_dev));
> - return -EINVAL;
> + ret = -EINVAL;
> + goto err_larbdev_put;
> }
> return 0;
>
> @@ -1402,8 +1407,12 @@ static int mtk_iommu_probe(struct
> platform_device *pdev)
> iommu_device_sysfs_remove(&data->iommu);
> out_list_del:
> list_del(&data->list);
> - if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM))
> + if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM)) {
> device_link_remove(data->smicomm_dev, dev);
> +
> + for (i = 0; i < MTK_LARB_NR_MAX; i++)
> + put_device(data->larb_imu[i].dev);
> + }
> out_runtime_disable:
> pm_runtime_disable(dev);
> return ret;
> @@ -1423,6 +1432,9 @@ static void mtk_iommu_remove(struct
> platform_device *pdev)
> if (MTK_IOMMU_IS_TYPE(data->plat_data, MTK_IOMMU_TYPE_MM)) {
> device_link_remove(data->smicomm_dev, &pdev->dev);
> component_master_del(&pdev->dev, &mtk_iommu_com_ops);
> +
> + for (i = 0; i < MTK_LARB_NR_MAX; i++)
> + put_device(data->larb_imu[i].dev);
> }
> pm_runtime_disable(&pdev->dev);
> for (i = 0; i < data->plat_data->banks_num; i++) {
> --
> 2.49.1
>