6.1-stable review patch. If anyone has any objections, please let me know.
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From: Yong Wu yong.wu@mediatek.com
[ Upstream commit 6cde583d5352818a51985b32a960cdde85ab3821 ]
No functional change. Just improve safety from dts.
All the larbs that connect to one IOMMU must connect with the same smi-common. This patch checks all the mediatek,smi property for each larb, If their mediatek,smi are different, it will return fails. Also avoid there is no available smi-larb nodes.
Suggested-by: Guenter Roeck groeck@chromium.org Signed-off-by: Yong Wu yong.wu@mediatek.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Matthias Brugger matthias.bgg@gmail.com Link: https://lore.kernel.org/r/20221018024258.19073-6-yong.wu@mediatek.com Signed-off-by: Joerg Roedel jroedel@suse.de Stable-dep-of: de83d4617f9f ("iommu/mediatek: fix use-after-free on probe deferral") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/mtk_iommu.c | 53 ++++++++++++++++++++++++++++++++-------------- 1 file changed, 37 insertions(+), 16 deletions(-)
--- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -1048,7 +1048,7 @@ static const struct component_master_ops static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **match, struct mtk_iommu_data *data) { - struct device_node *larbnode, *smicomm_node, *smi_subcomm_node; + struct device_node *larbnode, *frst_avail_smicomm_node = NULL; struct platform_device *plarbdev, *pcommdev; struct device_link *link; int i, larb_nr, ret; @@ -1060,6 +1060,7 @@ static int mtk_iommu_mm_dts_parse(struct return -EINVAL;
for (i = 0; i < larb_nr; i++) { + struct device_node *smicomm_node, *smi_subcomm_node; u32 id;
larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i); @@ -1100,27 +1101,47 @@ static int mtk_iommu_mm_dts_parse(struct goto err_larbdev_put; }
+ /* Get smi-(sub)-common dev from the last larb. */ + smi_subcomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0); + if (!smi_subcomm_node) { + ret = -EINVAL; + goto err_larbdev_put; + } + + /* + * It may have two level smi-common. the node is smi-sub-common if it + * has a new mediatek,smi property. otherwise it is smi-commmon. + */ + smicomm_node = of_parse_phandle(smi_subcomm_node, "mediatek,smi", 0); + if (smicomm_node) + of_node_put(smi_subcomm_node); + else + smicomm_node = smi_subcomm_node; + + /* + * All the larbs that connect to one IOMMU must connect with the same + * smi-common. + */ + if (!frst_avail_smicomm_node) { + frst_avail_smicomm_node = smicomm_node; + } else if (frst_avail_smicomm_node != smicomm_node) { + dev_err(dev, "mediatek,smi property is not right @larb%d.", id); + of_node_put(smicomm_node); + ret = -EINVAL; + goto err_larbdev_put; + } else { + of_node_put(smicomm_node); + } + component_match_add(dev, match, component_compare_dev, &plarbdev->dev); platform_device_put(plarbdev); }
- /* Get smi-(sub)-common dev from the last larb. */ - smi_subcomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0); - if (!smi_subcomm_node) + if (!frst_avail_smicomm_node) return -EINVAL;
- /* - * It may have two level smi-common. the node is smi-sub-common if it - * has a new mediatek,smi property. otherwise it is smi-commmon. - */ - smicomm_node = of_parse_phandle(smi_subcomm_node, "mediatek,smi", 0); - if (smicomm_node) - of_node_put(smi_subcomm_node); - else - smicomm_node = smi_subcomm_node; - - pcommdev = of_find_device_by_node(smicomm_node); - of_node_put(smicomm_node); + pcommdev = of_find_device_by_node(frst_avail_smicomm_node); + of_node_put(frst_avail_smicomm_node); if (!pcommdev) return -ENODEV; data->smicomm_dev = &pcommdev->dev;