[kbuild-all] Re: [PATCH net] net: dsa: Centralize validation of VLAN configuration

Hi Tobias, I love your patch! Perhaps something to improve: [auto build test WARNING on net/master] url: https://github.com/0day-ci/linux/commits/Tobias-Waldekranz/net-dsa-Centra... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git a25f822285420486f5da434efc8d940d42a83bce config: powerpc-randconfig-r006-20210316 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 50c7504a93fdb90c26870db8c8ea7add895c7725) 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 powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/0day-ci/linux/commit/9a35f7597b676a3bdaa9dd753e0a7d11f... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Tobias-Waldekranz/net-dsa-Centralize-validation-of-VLAN-configuration/20210316-035618 git checkout 9a35f7597b676a3bdaa9dd753e0a7d11fb132ed5 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): else if (is_vlan_dev(info->upper_dev)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ net/dsa/slave.c:2077:7: note: uninitialized use occurs here if (err) ^~~ net/dsa/slave.c:2074:8: note: remove the 'if' if its condition is always true else if (is_vlan_dev(info->upper_dev)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ net/dsa/slave.c:2070:10: note: initialize the variable 'err' to silence this warning int err; ^ = 0 1 warning generated. vim +2074 net/dsa/slave.c 2059 2060 static int dsa_slave_netdevice_event(struct notifier_block *nb, 2061 unsigned long event, void *ptr) 2062 { 2063 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 2064 2065 switch (event) { 2066 case NETDEV_PRECHANGEUPPER: { 2067 struct netdev_notifier_changeupper_info *info = ptr; 2068 struct dsa_switch *ds; 2069 struct dsa_port *dp; 2070 int err; 2071 2072 if (is_vlan_dev(dev)) 2073 err = dsa_prevent_bridging_8021q_upper(dev, ptr); 2075 err = dsa_slave_check_8021q_upper(dev, ptr); 2076 2077 if (err) 2078 return err; 2079 2080 if (!dsa_slave_dev_check(dev)) 2081 return NOTIFY_DONE; 2082 2083 dp = dsa_slave_to_port(dev); 2084 ds = dp->ds; 2085 2086 if (ds->ops->port_prechangeupper) { 2087 err = ds->ops->port_prechangeupper(ds, dp->index, info); 2088 if (err) 2089 return notifier_from_errno(err); 2090 } 2091 break; 2092 } 2093 case NETDEV_CHANGEUPPER: 2094 if (dsa_slave_dev_check(dev)) 2095 return dsa_slave_changeupper(dev, ptr); 2096 2097 if (netif_is_lag_master(dev)) 2098 return dsa_slave_lag_changeupper(dev, ptr); 2099 2100 break; 2101 case NETDEV_CHANGELOWERSTATE: { 2102 struct netdev_notifier_changelowerstate_info *info = ptr; 2103 struct dsa_port *dp; 2104 int err; 2105 2106 if (!dsa_slave_dev_check(dev)) 2107 break; 2108 2109 dp = dsa_slave_to_port(dev); 2110 2111 err = dsa_port_lag_change(dp, info->lower_state_info); 2112 return notifier_from_errno(err); 2113 } 2114 case NETDEV_GOING_DOWN: { 2115 struct dsa_port *dp, *cpu_dp; 2116 struct dsa_switch_tree *dst; 2117 LIST_HEAD(close_list); 2118 2119 if (!netdev_uses_dsa(dev)) 2120 return NOTIFY_DONE; 2121 2122 cpu_dp = dev->dsa_ptr; 2123 dst = cpu_dp->ds->dst; 2124 2125 list_for_each_entry(dp, &dst->ports, list) { 2126 if (!dsa_is_user_port(dp->ds, dp->index)) 2127 continue; 2128 2129 list_add(&dp->slave->close_list, &close_list); 2130 } 2131 2132 dev_close_many(&close_list, true); 2133 2134 return NOTIFY_OK; 2135 } 2136 default: 2137 break; 2138 } 2139 2140 return NOTIFY_DONE; 2141 } 2142 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org