tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   3fb6d0e00efc958d01c2f109c8453033a2d96796
commit: a0cd7a7c4bc004587d1f4785a320f58e72d880eb mm: simplify free_highmem_page() and free_reserved_page()
date:   3 days ago
config: microblaze-randconfig-r006-20210226 (attached as .config)
compiler: microblaze-linux-gcc (GCC) 9.3.0
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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a0cd7a7c4bc004587d1f4785a320f58e72d880eb
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout a0cd7a7c4bc004587d1f4785a320f58e72d880eb
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=microblaze 

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

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

>> WARNING: modpost: vmlinux.o(.text.unlikely+0x23ac): Section mismatch in reference from the function highmem_setup() to the function .meminit.text:memblock_is_reserved()
The function highmem_setup() references
the function __meminit memblock_is_reserved().
This is often because highmem_setup lacks a __meminit
annotation or the annotation of memblock_is_reserved is wrong.

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