CC: llvm(a)lists.linux.dev CC: kbuild-all(a)lists.01.org CC: linux-kernel(a)vger.kernel.org TO: Cai Huoqing <caihuoqing(a)baidu.com&gt; tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: d58071a8a76d779eedab38033ae4c821c30295a5 commit: fbcf8a340150abd20bf44fc706362b0827157fe8 net: ethernet: actions: Add helper dependency on COMPILE_TEST date: 3 months ago :::::: branch date: 2 days ago :::::: commit date: 3 months ago config: arm-randconfig-c002-20211001 (https://download.01.org/0day-ci/archive/20211201/202112010219.RWu2F2Ib-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 962e503cc8bc411f7523cc393acae8aae425b1c4) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout fbcf8a340150abd20bf44fc706362b0827157fe8 # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; clang-analyzer warnings: (new ones prefixed by >>) 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 7 warnings generated. Suppressed 7 warnings (7 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 10 warnings generated. drivers/net/can/ti_hecc.c:783:3: warning: Value stored to 'int_status' is never read [clang-analyzer-deadcode.DeadStores] int_status = hecc_read(priv, HECC_CANGIF1); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/can/ti_hecc.c:783:3: note: Value stored to 'int_status' is never read int_status = hecc_read(priv, HECC_CANGIF1); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/can/ti_hecc.c:786:3: warning: Value stored to 'int_status' is never read [clang-analyzer-deadcode.DeadStores] int_status = hecc_read(priv, HECC_CANGIF0); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/can/ti_hecc.c:786:3: note: Value stored to 'int_status' is never read int_status = hecc_read(priv, HECC_CANGIF0); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/can/ti_hecc.c:861:22: warning: Value stored to 'np' during its initialization is never read [clang-analyzer-deadcode.DeadStores] struct device_node *np = pdev->dev.of_node; ^~ ~~~~~~~~~~~~~~~~~ drivers/net/can/ti_hecc.c:861:22: note: Value stored to 'np' during its initialization is never read struct device_node *np = pdev->dev.of_node; ^~ ~~~~~~~~~~~~~~~~~ Suppressed 7 warnings (7 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 7 warnings generated. Suppressed 7 warnings (7 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 9 warnings generated. desc->control |= OWL_EMAC_BIT_RDES1_RER; ^ drivers/net/ethernet/actions/owl-emac.c:1420:2: note: '?' condition is false if (ret) ^ include/linux/compiler.h:56:28: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ include/linux/compiler.h:58:31: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^ drivers/net/ethernet/actions/owl-emac.c:1420:6: note: 'ret' is 0 if (ret) ^ include/linux/compiler.h:56:47: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^~~~ include/linux/compiler.h:58:86: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~ include/linux/compiler.h:69:3: note: expanded from macro '__trace_if_value' (cond) ? \ ^~~~ drivers/net/ethernet/actions/owl-emac.c:1420:2: note: '?' condition is false if (ret) ^ include/linux/compiler.h:56:28: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ include/linux/compiler.h:58:69: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^ include/linux/compiler.h:69:2: note: expanded from macro '__trace_if_value' (cond) ? \ ^ drivers/net/ethernet/actions/owl-emac.c:1420:2: note: Taking false branch if (ret) ^ include/linux/compiler.h:56:23: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ drivers/net/ethernet/actions/owl-emac.c:1423:2: note: Assuming the condition is false if (netif_running(netdev)) { ^ include/linux/compiler.h:56:45: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler.h:58:52: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~ drivers/net/ethernet/actions/owl-emac.c:1423:2: note: '?' condition is false if (netif_running(netdev)) { ^ include/linux/compiler.h:56:28: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ include/linux/compiler.h:58:31: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^ drivers/net/ethernet/actions/owl-emac.c:1423:2: note: '?' condition is true if (netif_running(netdev)) { ^ include/linux/compiler.h:56:28: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ include/linux/compiler.h:58:69: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^ include/linux/compiler.h:69:2: note: expanded from macro '__trace_if_value' (cond) ? \ ^ drivers/net/ethernet/actions/owl-emac.c:1423:2: note: Taking true branch if (netif_running(netdev)) { ^ include/linux/compiler.h:56:23: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ drivers/net/ethernet/actions/owl-emac.c:1427:9: note: Calling 'owl_emac_enable' ret = owl_emac_enable(netdev, true); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/actions/owl-emac.c:1042:8: note: Calling 'owl_emac_ring_prepare_rx' ret = owl_emac_ring_prepare_rx(priv); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/actions/owl-emac.c:184:2: note: 'desc' declared without an initial value struct owl_emac_ring_desc *desc; ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/actions/owl-emac.c:189:14: note: Assuming 'i' is >= field 'size' for (i = 0; i < ring->size; i++) { ^~~~~~~~~~~~~~ drivers/net/ethernet/actions/owl-emac.c:189:2: note: Loop condition is false. Execution continues on line 210 for (i = 0; i < ring->size; i++) { ^ drivers/net/ethernet/actions/owl-emac.c:210:16: note: Access to field 'control' results in a dereference of an undefined pointer value (loaded from variable 'desc') desc->control |= OWL_EMAC_BIT_RDES1_RER; ~~~~ ^ drivers/net/ethernet/actions/owl-emac.c:233:16: warning: Access to field 'control' results in a dereference of an undefined pointer value (loaded from variable 'desc') [clang-analyzer-core.NullDereference] desc->control |= OWL_EMAC_BIT_TDES1_TER; ^ drivers/net/ethernet/actions/owl-emac.c:1420:2: note: '?' condition is false if (ret) vim +210 drivers/net/ethernet/actions/owl-emac.c de6e0b19823985 Cristian Ciocaltea 2021-03-22 178 de6e0b19823985 Cristian Ciocaltea 2021-03-22 179 static int owl_emac_ring_prepare_rx(struct owl_emac_priv *priv) de6e0b19823985 Cristian Ciocaltea 2021-03-22 180 { de6e0b19823985 Cristian Ciocaltea 2021-03-22 181 struct owl_emac_ring *ring = &priv->rx_ring; de6e0b19823985 Cristian Ciocaltea 2021-03-22 182 struct device *dev = owl_emac_get_dev(priv); de6e0b19823985 Cristian Ciocaltea 2021-03-22 183 struct net_device *netdev = priv->netdev; de6e0b19823985 Cristian Ciocaltea 2021-03-22 184 struct owl_emac_ring_desc *desc; de6e0b19823985 Cristian Ciocaltea 2021-03-22 185 struct sk_buff *skb; de6e0b19823985 Cristian Ciocaltea 2021-03-22 186 dma_addr_t dma_addr; de6e0b19823985 Cristian Ciocaltea 2021-03-22 187 int i; de6e0b19823985 Cristian Ciocaltea 2021-03-22 188 de6e0b19823985 Cristian Ciocaltea 2021-03-22 189 for (i = 0; i < ring->size; i++) { de6e0b19823985 Cristian Ciocaltea 2021-03-22 190 skb = owl_emac_alloc_skb(netdev); de6e0b19823985 Cristian Ciocaltea 2021-03-22 191 if (!skb) de6e0b19823985 Cristian Ciocaltea 2021-03-22 192 return -ENOMEM; de6e0b19823985 Cristian Ciocaltea 2021-03-22 193 de6e0b19823985 Cristian Ciocaltea 2021-03-22 194 dma_addr = owl_emac_dma_map_rx(priv, skb); de6e0b19823985 Cristian Ciocaltea 2021-03-22 195 if (dma_mapping_error(dev, dma_addr)) { de6e0b19823985 Cristian Ciocaltea 2021-03-22 196 dev_kfree_skb(skb); de6e0b19823985 Cristian Ciocaltea 2021-03-22 197 return -ENOMEM; de6e0b19823985 Cristian Ciocaltea 2021-03-22 198 } de6e0b19823985 Cristian Ciocaltea 2021-03-22 199 de6e0b19823985 Cristian Ciocaltea 2021-03-22 200 desc = &ring->descs[i]; de6e0b19823985 Cristian Ciocaltea 2021-03-22 201 desc->status = OWL_EMAC_BIT_RDES0_OWN; de6e0b19823985 Cristian Ciocaltea 2021-03-22 202 desc->control = skb_tailroom(skb) & OWL_EMAC_MSK_RDES1_RBS1; de6e0b19823985 Cristian Ciocaltea 2021-03-22 203 desc->buf_addr = dma_addr; de6e0b19823985 Cristian Ciocaltea 2021-03-22 204 desc->reserved = 0; de6e0b19823985 Cristian Ciocaltea 2021-03-22 205 de6e0b19823985 Cristian Ciocaltea 2021-03-22 206 ring->skbs[i] = skb; de6e0b19823985 Cristian Ciocaltea 2021-03-22 207 ring->skbs_dma[i] = dma_addr; de6e0b19823985 Cristian Ciocaltea 2021-03-22 208 } de6e0b19823985 Cristian Ciocaltea 2021-03-22 209 de6e0b19823985 Cristian Ciocaltea 2021-03-22 @210 desc->control |= OWL_EMAC_BIT_RDES1_RER; de6e0b19823985 Cristian Ciocaltea 2021-03-22 211 de6e0b19823985 Cristian Ciocaltea 2021-03-22 212 ring->head = 0; de6e0b19823985 Cristian Ciocaltea 2021-03-22 213 ring->tail = 0; de6e0b19823985 Cristian Ciocaltea 2021-03-22 214 de6e0b19823985 Cristian Ciocaltea 2021-03-22 215 return 0; de6e0b19823985 Cristian Ciocaltea 2021-03-22 216 } de6e0b19823985 Cristian Ciocaltea 2021-03-22 217 :::::: The code at line 210 was first introduced by commit :::::: de6e0b198239857943db395377dc1d2ddd6c05df net: ethernet: actions: Add Actions Semi Owl Ethernet MAC driver :::::: TO: Cristian Ciocaltea <cristian.ciocaltea(a)gmail.com&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org