Hi Andrew, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on net-next/master] [also build test WARNING on net/master mst-vhost/linux-next linus/master v5.17-rc1 next-20220125] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Andrew-Melnychenko/TUN-VirtioNet... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 6e667749271e58d34238cf700e543beabdbe6184 config: mips-allyesconfig (https://download.01.org/0day-ci/archive/20220125/202201252316.Wm0ucNBh-lk...) compiler: mips-linux-gcc (GCC) 11.2.0 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 # https://github.com/0day-ci/linux/commit/3c1c2daa10c8eac3d9b546fa8caf99fcb... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Andrew-Melnychenko/TUN-VirtioNet-USO-features-support/20220125-171057 git checkout 3c1c2daa10c8eac3d9b546fa8caf99fcb5a40454 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=mips SHELL=/bin/bash drivers/net/ 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 >>): drivers/net/tap.c: In function 'set_offload': 945 | if (arg & (TUN_F_USO4 | TUN_F_USO6) == (TUN_F_USO4 | TUN_F_USO6)) | ^ drivers/net/tap.c:958:26: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses] 958 | feature_mask & (TUN_F_USO4 | TUN_F_USO6) == (TUN_F_USO4 | TUN_F_USO6)) | ^ vim +945 drivers/net/tap.c 919 920 static int set_offload(struct tap_queue *q, unsigned long arg) 921 { 922 struct tap_dev *tap; 923 netdev_features_t features; 924 netdev_features_t feature_mask = 0; 925 926 tap = rtnl_dereference(q->tap); 927 if (!tap) 928 return -ENOLINK; 929 930 features = tap->dev->features; 931 932 if (arg & TUN_F_CSUM) { 933 feature_mask = NETIF_F_HW_CSUM; 934 935 if (arg & (TUN_F_TSO4 | TUN_F_TSO6)) { 936 if (arg & TUN_F_TSO_ECN) 937 feature_mask |= NETIF_F_TSO_ECN; 938 if (arg & TUN_F_TSO4) 939 feature_mask |= NETIF_F_TSO; 940 if (arg & TUN_F_TSO6) 941 feature_mask |= NETIF_F_TSO6; 942 } 943 944 /* TODO: for now USO4 and USO6 should work simultaneously */ 946 features |= NETIF_F_GSO_UDP_L4; 947 } 948 949 /* tun/tap driver inverts the usage for TSO offloads, where 950 * setting the TSO bit means that the userspace wants to 951 * accept TSO frames and turning it off means that user space 952 * does not support TSO. 953 * For tap, we have to invert it to mean the same thing. 954 * When user space turns off TSO, we turn off GSO/LRO so that 955 * user-space will not receive TSO frames. 956 */ 957 if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6) || 958 feature_mask & (TUN_F_USO4 | TUN_F_USO6) == (TUN_F_USO4 | TUN_F_USO6)) 959 features |= RX_OFFLOADS; 960 else 961 features &= ~RX_OFFLOADS; 962 963 /* tap_features are the same as features on tun/tap and 964 * reflect user expectations. 965 */ 966 tap->tap_features = feature_mask; 967 if (tap->update_features) 968 tap->update_features(tap, features); 969 970 return 0; 971 } 972 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org