Hi Huacai,

It's probably a bug fix that unveils the link errors.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   c2bf05db6c78f53ca5cd4b48f3b9b71f78d215f1
commit: d4b6f1562a3c3284adcef81d6e4f183d7d34b8a9 LoongArch: Add Non-Uniform Memory Access (NUMA) support
date:   6 months ago
config: loongarch-randconfig-s042-20221204
compiler: loongarch64-linux-gcc (GCC) 12.1.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.4-39-gce1a6720-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d4b6f1562a3c3284adcef81d6e4f183d7d34b8a9
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout d4b6f1562a3c3284adcef81d6e4f183d7d34b8a9
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=loongarch SHELL=/bin/bash

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

All errors (new ones prefixed by >>):

   loongarch64-linux-ld: arch/loongarch/kernel/env.o: in function `init_environ':
   env.c:(.init.text+0x10c): undefined reference to `efi'
   loongarch64-linux-ld: env.c:(.init.text+0x110): undefined reference to `efi'
   loongarch64-linux-ld: env.c:(.init.text+0x110): undefined reference to `efi'
   loongarch64-linux-ld: env.c:(.init.text+0x140): undefined reference to `efi_get_fdt_params'
   loongarch64-linux-ld: env.c:(.init.text+0x158): undefined reference to `efi_memmap_init_early'
   loongarch64-linux-ld: arch/loongarch/kernel/setup.o: in function `platform_init':
   setup.c:(.init.text+0x4d4): undefined reference to `efi_init'
>> loongarch64-linux-ld: setup.c:(.init.text+0x4d8): undefined reference to `init_numa_memory'
   loongarch64-linux-ld: setup.c:(.init.text+0x500): undefined reference to `efi_runtime_init'
   loongarch64-linux-ld: arch/loongarch/kernel/setup.o: in function `.L27':
>> setup.c:(.init.text+0x5e0): undefined reference to `num_processors'
>> loongarch64-linux-ld: setup.c:(.init.text+0x5e4): undefined reference to `num_processors'
>> loongarch64-linux-ld: setup.c:(.init.text+0x5e4): undefined reference to `num_processors'
>> loongarch64-linux-ld: setup.c:(.init.text+0x5ec): undefined reference to `disabled_cpus'
   loongarch64-linux-ld: setup.c:(.init.text+0x5f0): undefined reference to `disabled_cpus'
   loongarch64-linux-ld: setup.c:(.init.text+0x5f0): undefined reference to `disabled_cpus'
   loongarch64-linux-ld: arch/loongarch/kernel/mem.o: in function `memblock_init':
   mem.c:(.init.text+0x24): undefined reference to `efi'
   loongarch64-linux-ld: mem.c:(.init.text+0x28): undefined reference to `efi'
   loongarch64-linux-ld: mem.c:(.init.text+0x28): undefined reference to `efi'

sparse warnings: (new ones prefixed by >>)
>> arch/loongarch/kernel/numa.c:38:11: sparse: sparse: symbol 'phys_cpus_on_node' was not declared. Should it be static?

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp