Hi Hao,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Hao-Luo/bpf-BTF-support-for-ksyms/20200917-064052
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: powerpc-randconfig-s032-20200916 (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
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: v0.6.2-201-g24bdaac6-dirty
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=powerpc 

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


sparse warnings: (new ones prefixed by >>)

>> kernel/bpf/helpers.c:631:31: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected void const [noderef] __percpu *__vpp_verify @@     got void const * @@
>> kernel/bpf/helpers.c:631:31: sparse:     expected void const [noderef] __percpu *__vpp_verify
>> kernel/bpf/helpers.c:631:31: sparse:     got void const *

# https://github.com/0day-ci/linux/commit/3f6ea3c1c73efe466a96ff7499219fe3b03b8f48
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Hao-Luo/bpf-BTF-support-for-ksyms/20200917-064052
git checkout 3f6ea3c1c73efe466a96ff7499219fe3b03b8f48
vim +631 kernel/bpf/helpers.c

   625	
   626	BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu)
   627	{
   628		if (cpu >= nr_cpu_ids)
   629			return (unsigned long)NULL;
   630	
 > 631		return (unsigned long)per_cpu_ptr(ptr, cpu);
   632	}
   633	
   634	const struct bpf_func_proto bpf_per_cpu_ptr_proto = {
   635		.func		= bpf_per_cpu_ptr,
   636		.gpl_only	= false,
   637		.ret_type	= RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL,
   638		.arg1_type	= ARG_PTR_TO_PERCPU_BTF_ID,
   639		.arg2_type	= ARG_ANYTHING,
   640	};
   641	
 > 642	const struct bpf_func_proto bpf_get_current_task_proto __weak;
   643	const struct bpf_func_proto bpf_probe_read_user_proto __weak;
   644	const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
   645	const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
   646	const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
   647	

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