Re: [PATCH RFC bpf-next 1/1] bpf: Support 64-bit pointers to kfuncs

[kernel test robot <lkp@intel.com>]

Hi Ilya,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on bpf-next/master]

url:    https://github.com/intel-lab-lkp/linux/commits/Ilya-Leoshkevich/bpf-Support-64-bit-pointers-to-kfuncs/20230215-054702
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20230214212809.242632-2-iii%40linux.ibm.com
patch subject: [PATCH RFC bpf-next 1/1] bpf: Support 64-bit pointers to kfuncs
config: i386-randconfig-a002-20230213 (https://download.01.org/0day-ci/archive/20230216/202302161535.Vb9cejVb-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
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://github.com/intel-lab-lkp/linux/commit/5b93c73d640845b2e5ddd1b4af608f4896379002
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Ilya-Leoshkevich/bpf-Support-64-bit-pointers-to-kfuncs/20230215-054702
        git checkout 5b93c73d640845b2e5ddd1b4af608f4896379002
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash kernel/bpf/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302161535.Vb9cejVb-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> kernel/bpf/core.c:1227:13: warning: incompatible pointer to integer conversion assigning to 'u64' (aka 'unsigned long long') from 'u8 *' (aka 'unsigned char *') [-Wint-conversion]
           *func_addr = addr;
                      ^ ~~~~
   1 warning generated.


vim +1227 kernel/bpf/core.c

  1181	
  1182	int bpf_jit_get_func_addr(const struct bpf_prog *prog,
  1183				  const struct bpf_insn *insn, bool extra_pass,
  1184				  u64 *func_addr, bool *func_addr_fixed)
  1185	{
  1186		s16 off = insn->off;
  1187		s32 imm = insn->imm;
  1188		bool fixed;
  1189		u8 *addr;
  1190		int err;
  1191	
  1192		switch (insn->src_reg) {
  1193		case BPF_PSEUDO_CALL:
  1194			/* Place-holder address till the last pass has collected
  1195			 * all addresses for JITed subprograms in which case we
  1196			 * can pick them up from prog->aux.
  1197			 */
  1198			if (!extra_pass)
  1199				addr = NULL;
  1200			else if (prog->aux->func &&
  1201				 off >= 0 && off < prog->aux->func_cnt)
  1202				addr = (u8 *)prog->aux->func[off]->bpf_func;
  1203			else
  1204				return -EINVAL;
  1205			fixed = false;
  1206			break;
  1207		case 0:
  1208			/* Address of a BPF helper call. Since part of the core
  1209			 * kernel, it's always at a fixed location. __bpf_call_base
  1210			 * and the helper with imm relative to it are both in core
  1211			 * kernel.
  1212			 */
  1213			addr = (u8 *)__bpf_call_base + imm;
  1214			fixed = true;
  1215			break;
  1216		case BPF_PSEUDO_KFUNC_CALL:
  1217			err = bpf_get_kfunc_addr(prog, imm, off, &addr);
  1218			if (err)
  1219				return err;
  1220			fixed = true;
  1221			break;
  1222		default:
  1223			return -EINVAL;
  1224		}
  1225	
  1226		*func_addr_fixed = fixed;
> 1227		*func_addr = addr;
  1228		return 0;
  1229	}
  1230	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests