Hi, 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/menglong8-dong-gmail-com/net-tcp-add-sysctl-for-controling-tcp-window-shrink/20230517-204436 base: net-next/main patch link: https://lore.kernel.org/r/20230517124201.441634-4-imagedong%40tencent.com patch subject: [PATCH net-next 3/3] net: tcp: handle window shrink properly config: m68k-allyesconfig compiler: m68k-linux-gcc (GCC) 12.1.0 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/intel-lab-lkp/linux/commit/3712ab843c151a10d6570ded9d8c77ad831a7a41 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review menglong8-dong-gmail-com/net-tcp-add-sysctl-for-controling-tcp-window-shrink/20230517-204436 git checkout 3712ab843c151a10d6570ded9d8c77ad831a7a41 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=m68k olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=m68k SHELL=/bin/bash net/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot | Closes: https://lore.kernel.org/oe-kbuild-all/202305180050.jwEMlDOS-lkp@intel.com/ All warnings (new ones prefixed by >>): >> net/ipv4/tcp_input.c:3477: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * This function is called only when there are packets in the rtx queue, vim +3477 net/ipv4/tcp_input.c 3475 3476 /** > 3477 * This function is called only when there are packets in the rtx queue, 3478 * which means that the packets out is not 0. 3479 * 3480 * NOTE: we only handle window shrink case in this part. 3481 */ 3482 static void tcp_ack_probe_shrink(struct sock *sk) 3483 { 3484 struct inet_connection_sock *icsk = inet_csk(sk); 3485 unsigned long when; 3486 3487 if (!sysctl_tcp_wnd_shrink) 3488 return; 3489 3490 if (tcp_rtx_overflow(sk)) { 3491 when = tcp_probe0_when(sk, TCP_RTO_MAX); 3492 3493 when = tcp_clamp_probe0_to_user_timeout(sk, when); 3494 tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, when, TCP_RTO_MAX); 3495 } else { 3496 /* check if recover from window shrink */ 3497 if (icsk->icsk_pending != ICSK_TIME_PROBE0) 3498 return; 3499 3500 icsk->icsk_backoff = 0; 3501 icsk->icsk_probes_tstamp = 0; 3502 inet_csk_clear_xmit_timer(sk, ICSK_TIME_PROBE0); 3503 if (!tcp_rtx_queue_empty(sk)) 3504 tcp_retransmit_timer(sk); 3505 } 3506 } 3507 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki