Re: [PATCH bpf-next v3 4/6] bpf: Introduce bpf_per_cpu_ptr()

From: kernel test robot
Date: Wed Sep 16 2020 - 21:18:39 EST


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@xxxxxxxxx>


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

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

Attachment: .config.gz
Description: application/gzip