On Mon, Sep 21, 2020 at 11:11 AM Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx> wrote: > > On Thu, Sep 17, 2020 at 12:14 PM Hao Luo <haoluo@xxxxxxxxxx> wrote: > > > > I need to cast the pointer to "const void __percpu *" before passing > > into per_cpu_ptr. I will update and resend. > > You can try just declaring it as __percpu in BPF_CALL_2 macro. That > might work, or not, depending on how exactly BPF_CALL macros are > implemented (I haven't checked). > ACK. IMO it's probably better cast inside, rather than depending on BPF_CALL macros. The parameters are not true percpu pointers anyway and potential changes on BPF_CALL may break this, I'm afraid. > > > > On Wed, Sep 16, 2020 at 6:14 PM kernel test robot <lkp@xxxxxxxxx> wrote: > > > > > > 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