Hi Xuan, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Xuan-Zhuo/virtio-net-support-xdp... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 8ef7adc6beb2ef0bce83513dc9e4505e7b21e8c2 config: um-allmodconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/32403bd72dd27e9d773cfce22af2e46ae... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Xuan-Zhuo/virtio-net-support-xdp-socket-zero-copy-xmit/20210413-111831 git checkout 32403bd72dd27e9d773cfce22af2e46aeec0a3b1 # save the attached .config to linux build tree make W=1 ARCH=um 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 >>): cc1: warning: arch/um/include/uapi: No such file or directory [-Wmissing-include-dirs] net/8021q/vlanproc.c: In function 'vlandev_seq_show': 255 | "%s VID: %d REORDER_HDR: %i dev->priv_flags: %hx\n", | ~~^ | | | int | %llx 256 | vlandev->name, vlan->vlan_id, 257 | (int)(vlan->flags & 1), vlandev->priv_flags); | ~~~~~~~~~~~~~~~~~~~ | | | netdev_priv_flags_t {aka long long unsigned int} vim +255 net/8021q/vlanproc.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 240 ^1da177e4c3f41 Linus Torvalds 2005-04-16 241 static int vlandev_seq_show(struct seq_file *seq, void *offset) ^1da177e4c3f41 Linus Torvalds 2005-04-16 242 { ^1da177e4c3f41 Linus Torvalds 2005-04-16 243 struct net_device *vlandev = (struct net_device *) seq->private; 7da82c06ded105 Jiri Pirko 2011-12-08 244 const struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev); 28172739f0a276 Eric Dumazet 2010-07-07 245 struct rtnl_link_stats64 temp; be1f3c2c027cc5 Ben Hutchings 2010-06-08 246 const struct rtnl_link_stats64 *stats; be1f3c2c027cc5 Ben Hutchings 2010-06-08 247 static const char fmt64[] = "%30s %12llu\n"; ^1da177e4c3f41 Linus Torvalds 2005-04-16 248 int i; ^1da177e4c3f41 Linus Torvalds 2005-04-16 249 26a25239d7a660 Joonwoo Park 2008-07-08 250 if (!is_vlan_dev(vlandev)) ^1da177e4c3f41 Linus Torvalds 2005-04-16 251 return 0; ^1da177e4c3f41 Linus Torvalds 2005-04-16 252 28172739f0a276 Eric Dumazet 2010-07-07 253 stats = dev_get_stats(vlandev, &temp); 2029cc2c84fb11 Patrick McHardy 2008-01-21 254 seq_printf(seq, 2029cc2c84fb11 Patrick McHardy 2008-01-21 @255 "%s VID: %d REORDER_HDR: %i dev->priv_flags: %hx\n", --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org