[kbuild-all] Re: [kbuild] [chrome-os:chromeos-5.10 94/100] drivers/iommu/mtk_iommu.c:865 mtk_iommu_mm_dts_parse() error: uninitialized symbol 'larbnode'.

tree: https://chromium.googlesource.com/chromiumos/third_party/kernel chromeos-5.10 head: 3eae3ffb66ef2c07a94f385c4160c405cc3a490b commit: 7fc5fdfd89dcb4030def0f07c3a015509dcca1c6 [94/100] BACKPORT: FROMLIST: iommu/mediatek: Contain MM IOMMU flow with the MM TYPE config: riscv-randconfig-m031-20211210 (https://download.01.org/0day-ci/archive/20211210/202112101915.YoEDCiBh-lk... ) compiler: riscv64-linux-gcc (GCC) 11.2.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/iommu/mtk_iommu.c:865 mtk_iommu_mm_dts_parse() error: uninitialized symbol 'larbnode'. drivers/iommu/mtk_iommu.c:878 mtk_iommu_mm_dts_parse() warn: passing zero to 'PTR_ERR' vim +/larbnode +865 drivers/iommu/mtk_iommu.c 7fc5fdfd89dcb4 Yong Wu 2021-09-23 824 static int mtk_iommu_mm_dts_parse(struct device *dev, 7fc5fdfd89dcb4 Yong Wu 2021-09-23 825 struct component_match **match, 7fc5fdfd89dcb4 Yong Wu 2021-09-23 826 struct mtk_iommu_data *data) 7fc5fdfd89dcb4 Yong Wu 2021-09-23 827 { 7fc5fdfd89dcb4 Yong Wu 2021-09-23 828 struct platform_device *plarbdev; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 829 struct device_link *link; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 830 struct device_node *larbnode, *smicomm_node; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 831 int i, larb_nr, ret; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 832 7fc5fdfd89dcb4 Yong Wu 2021-09-23 833 larb_nr = of_count_phandle_with_args(dev->of_node, "mediatek,larbs", NULL); Can of_count_phandle_with_args() return 0? That's what the uninitialized variable warning is complaining about. No idea if it's really possible.

7fc5fdfd89dcb4 Yong Wu 2021-09-23 834 if (larb_nr < 0) 7fc5fdfd89dcb4 Yong Wu 2021-09-23 835 return larb_nr; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 836 7fc5fdfd89dcb4 Yong Wu 2021-09-23 837 for (i = 0; i < larb_nr; i++) { 7fc5fdfd89dcb4 Yong Wu 2021-09-23 838 u32 id; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 839 7fc5fdfd89dcb4 Yong Wu 2021-09-23 840 larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 841 if (!larbnode) 7fc5fdfd89dcb4 Yong Wu 2021-09-23 842 return -EINVAL; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 843 7fc5fdfd89dcb4 Yong Wu 2021-09-23 844 if (!of_device_is_available(larbnode)) { 7fc5fdfd89dcb4 Yong Wu 2021-09-23 845 of_node_put(larbnode); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 846 continue; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 847 } 7fc5fdfd89dcb4 Yong Wu 2021-09-23 848 7fc5fdfd89dcb4 Yong Wu 2021-09-23 849 ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 850 if (ret)/* The id is consecutive if there is no this property */ 7fc5fdfd89dcb4 Yong Wu 2021-09-23 851 id = i; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 852 7fc5fdfd89dcb4 Yong Wu 2021-09-23 853 plarbdev = of_find_device_by_node(larbnode); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 854 if (!plarbdev || !plarbdev->dev.driver) { 7fc5fdfd89dcb4 Yong Wu 2021-09-23 855 of_node_put(larbnode); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 856 return -EPROBE_DEFER; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 857 } 7fc5fdfd89dcb4 Yong Wu 2021-09-23 858 data->larb_imu[id].dev = &plarbdev->dev; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 859 7fc5fdfd89dcb4 Yong Wu 2021-09-23 860 component_match_add_release(dev, match, release_of, 7fc5fdfd89dcb4 Yong Wu 2021-09-23 861 compare_of, larbnode); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 862 } 7fc5fdfd89dcb4 Yong Wu 2021-09-23 863 7fc5fdfd89dcb4 Yong Wu 2021-09-23 864 /* Get smi-common dev from the last larb. */ 7fc5fdfd89dcb4 Yong Wu 2021-09-23 @865 smicomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0); ^^^^^^^^ 7fc5fdfd89dcb4 Yong Wu 2021-09-23 866 if (!smicomm_node) 7fc5fdfd89dcb4 Yong Wu 2021-09-23 867 return -EINVAL; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 868 7fc5fdfd89dcb4 Yong Wu 2021-09-23 869 plarbdev = of_find_device_by_node(smicomm_node); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 870 of_node_put(smicomm_node); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 871 data->smicomm_dev = &plarbdev->dev; 7fc5fdfd89dcb4 Yong Wu 2021-09-23 872 7fc5fdfd89dcb4 Yong Wu 2021-09-23 873 link = device_link_add(data->smicomm_dev, dev, 7fc5fdfd89dcb4 Yong Wu 2021-09-23 874 DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 875 7fc5fdfd89dcb4 Yong Wu 2021-09-23 876 if (!link) { 7fc5fdfd89dcb4 Yong Wu 2021-09-23 877 dev_err(dev, "Unable link %s.\n", dev_name(data->smicomm_dev)); 7fc5fdfd89dcb4 Yong Wu 2021-09-23 @878 return PTR_ERR(link); ^^^^^^^^^^^^^^^^^^^^^ This is equivalent to return 0;