[PATCH 6.1 0863/1146] iommu/mediatek: Add error path for loop of mm_dts_parse

Greg Kroah-Hartman
2022-12-28T16:37:27Z

From: Yong Wu <yong.wu@mediatek.com>

[ Upstream commit 26593928564cf5b576ff05d3cbd958f57c9534bb ]

The mtk_iommu_mm_dts_parse will parse the smi larbs nodes. if the i+1
larb is parsed fail, we should put_device for the i..0 larbs.

There are two places need to comment:
1) The larbid may be not linear mapping, we should loop whole
the array in the error path.
2) I move this line position: "data->larb_imu[id].dev = &plarbdev->dev;"
before "if (!plarbdev->dev.driver)", That means set
data->larb_imu[id].dev before the error path. then we don't need
"platform_device_put(plarbdev)" again in probe_defer case. All depend
on "put_device" of the error path in error cases.

Fixes: d2e9a1102cfc ("iommu/mediatek: Contain MM IOMMU flow with the MM TYPE")
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/20221018024258.19073-4-yong.wu@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/mtk_iommu.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index ba5abfc2890c..f4a315da4535 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -1056,8 +1056,10 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m
u32 id;

larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
- if (!larbnode)
- return -EINVAL;
+ if (!larbnode) {
+ ret = -EINVAL;
+ goto err_larbdev_put;
+ }

if (!of_device_is_available(larbnode)) {
of_node_put(larbnode);
@@ -1070,14 +1072,16 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m

plarbdev = of_find_device_by_node(larbnode);
of_node_put(larbnode);
- if (!plarbdev)
- return -ENODEV;
+ if (!plarbdev) {
+ ret = -ENODEV;
+ goto err_larbdev_put;
+ }
+ data->larb_imu[id].dev = &plarbdev->dev;

if (!plarbdev->dev.driver) {
- platform_device_put(plarbdev);
- return -EPROBE_DEFER;
+ ret = -EPROBE_DEFER;
+ goto err_larbdev_put;
}
- data->larb_imu[id].dev = &plarbdev->dev;

component_match_add(dev, match, component_compare_dev, &plarbdev->dev);
platform_device_put(plarbdev);
@@ -1112,6 +1116,15 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, struct component_match **m
return -EINVAL;
}
return 0;
+
+err_larbdev_put:
+ /* id may be not linear mapping, loop whole the array */
+ for (i = MTK_LARB_NR_MAX - 1; i >= 0; i++) {
+ if (!data->larb_imu[i].dev)
+ continue;
+ put_device(data->larb_imu[i].dev);
+ }
+ return ret;
}

static int mtk_iommu_probe(struct platform_device *pdev)
--
2.35.1