Hi Heng, kernel test robot noticed the following build warnings: [auto build test WARNING on net-next/main] url: https://github.com/intel-lab-lkp/linux/commits/Heng-Qi/virtio-net-a-helper-for-probing-the-pseudo-header-checksum/20230619-190212 base: net-next/main patch link: https://lore.kernel.org/r/20230619105738.117733-3-hengqi%40linux.alibaba.com patch subject: [PATCH net-next 2/4] virtio-net: reprobe csum related fields for skb passed by XDP config: x86_64-randconfig-r014-20230619 (https://download.01.org/0day-ci/archive/20230619/202306192151.YMz3NiKw-lkp@xxxxxxxxx/config) compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a) reproduce: (https://download.01.org/0day-ci/archive/20230619/202306192151.YMz3NiKw-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202306192151.YMz3NiKw-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): drivers/net/virtio_net.c:1648:17: error: call to undeclared function 'csum_ipv6_magic'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration] uh->check = ~csum_ipv6_magic((const struct in6_addr *)&ip6h->saddr, ^ drivers/net/virtio_net.c:1648:17: note: did you mean 'csum_tcpudp_magic'? include/asm-generic/checksum.h:52:1: note: 'csum_tcpudp_magic' declared here csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len, ^ drivers/net/virtio_net.c:1657:17: error: call to undeclared function 'csum_ipv6_magic'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration] th->check = ~csum_ipv6_magic((const struct in6_addr *)&ip6h->saddr, ^ >> drivers/net/virtio_net.c:1695:19: warning: use of logical '&&' with constant operand [-Wconstant-logical-operand] } else if (flags && VIRTIO_NET_HDR_F_DATA_VALID) { ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/virtio_net.c:1695:19: note: use '&' for a bitwise operation } else if (flags && VIRTIO_NET_HDR_F_DATA_VALID) { ^~ & drivers/net/virtio_net.c:1695:19: note: remove constant to silence this warning } else if (flags && VIRTIO_NET_HDR_F_DATA_VALID) { ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 warning and 2 errors generated. vim +1695 drivers/net/virtio_net.c 1667 1668 static int virtnet_set_csum_after_xdp(struct virtnet_info *vi, 1669 struct sk_buff *skb, 1670 __u8 flags) 1671 { 1672 int err; 1673 1674 /* When XDP program is loaded, for example, the vm-vm scenario 1675 * on the same host, packets marked as VIRTIO_NET_HDR_F_NEEDS_CSUM 1676 * will travel. Although these packets are safe from the point of 1677 * view of the vm, to avoid modification by XDP and successful 1678 * forwarding in the upper layer, we re-probe the necessary checksum 1679 * related information: skb->csum_{start, offset}, pseudo-header csum. 1680 * 1681 * This benefits us: 1682 * 1. XDP can be loaded when there's _F_GUEST_CSUM. 1683 * 2. The device verifies the checksum of packets , especially 1684 * benefiting for large packets. 1685 * 3. In the same-host vm-vm scenario, packets marked as 1686 * VIRTIO_NET_HDR_F_NEEDS_CSUM are no longer dropped after being 1687 * processed by XDP. 1688 */ 1689 if (flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 1690 err = virtnet_flow_dissect_udp_tcp(vi, skb); 1691 if (err < 0) 1692 return -EINVAL; 1693 1694 skb->ip_summed = CHECKSUM_PARTIAL; > 1695 } else if (flags && VIRTIO_NET_HDR_F_DATA_VALID) { 1696 /* We want to benefit from this: XDP guarantees that packets marked 1697 * as VIRTIO_NET_HDR_F_DATA_VALID still have correct csum after they 1698 * are processed. 1699 */ 1700 skb->ip_summed = CHECKSUM_UNNECESSARY; 1701 } 1702 1703 return 0; 1704 } 1705 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
