[jirislaby:devel 27/29] ERROR: modpost: "uart_port_tx" [vmlinux] is a static EXPORT_SYMBOL

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/jirislaby/linux.git devel
head:   4c13e2f9afce43aef0685eb559a8fc64dc40aa03
commit: 684fee07c7f9eee78841ae735e5df419cd07aa57 [27/29] tty: serial, add uart_port_tx helper
config: x86_64-randconfig-a004-20220131 (https://download.01.org/0day-ci/archive/20220204/202202040313.zFpGQpCn-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/jirislaby/linux.git/commit/?id=684fee07c7f9eee78841ae735e5df419cd07aa57
        git remote add jirislaby https://git.kernel.org/pub/scm/linux/kernel/git/jirislaby/linux.git
        git fetch --no-tags jirislaby devel
        git checkout 684fee07c7f9eee78841ae735e5df419cd07aa57
        # save the config file to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "uart_port_tx" [vmlinux] is a static EXPORT_SYMBOL

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0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx