Hi Yonghong, [FYI, it's a private test report for your RFC patch.] [auto build test ERROR on bpf-next/master] [also build test ERROR on bpf/master net/master net-next/master linus/master v5.7-rc1 next-20200416] [cannot apply to vhost/linux-next ipvs/master] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Yonghong-Song/bpf-implement-bpf-... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: i386-debian-10.3 (attached as .config) compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): kernel//bpf/dump.c: In function 'bpf_dump_query': prog_ctx_type_name = tinfo->prog_ctx_type_name; ^~ vim +143 kernel//bpf/dump.c 95 96 int bpf_dump_query(const union bpf_attr *attr, union bpf_attr __user *uattr) 97 { 98 struct bpf_dump_info __user *ubpf_dinfo; 99 struct bpfdump_target_info *tinfo; 100 struct dumper_inode_info *i_info; 101 struct bpf_dump_info bpf_dinfo; 102 const char *prog_ctx_type_name; 103 void * __user tname_buf; 104 u32 tname_len, info_len; 105 struct file *filp; 106 struct fd qfd; 107 int err = 0; 108 109 qfd = fdget(attr->info.dump_query_fd); 110 filp = qfd.file; 111 if (!filp) 112 return -EBADF; 113 114 if (filp->f_op != &bpf_dumper_ops && 115 filp->f_inode->i_op != &bpfdump_dir_iops) { 116 err = -EINVAL; 117 goto done; 118 } 119 120 info_len = attr->info.info_len; 121 ubpf_dinfo = u64_to_user_ptr(attr->info.info); 122 err = bpf_check_uarg_tail_zero(ubpf_dinfo, sizeof(bpf_dinfo), 123 info_len); 124 if (err) 125 goto done; 126 info_len = min_t(u32, sizeof(bpf_dinfo), info_len); 127 128 memset(&bpf_dinfo, 0, sizeof(bpf_dinfo)); 129 if (copy_from_user(&bpf_dinfo, ubpf_dinfo, info_len)) { 130 err = -EFAULT; 131 goto done; 132 } 133 134 /* copy prog_id for dumpers */ 135 if (filp->f_op == &bpf_dumper_ops) { 136 i_info = filp->f_inode->i_private; 137 bpf_dinfo.prog_id = i_info->prog->aux->id; 138 tinfo = i_info->tinfo; 139 } else { 140 tinfo = filp->f_inode->i_private; 141 } 142 144 145 tname_len = strlen(prog_ctx_type_name) + 1; 146 if (bpf_dinfo.type_name_buf_len < tname_len) { 147 err = -ENOSPC; 148 goto done; 149 } 150 151 /* copy prog_ctx_type_name */ 152 tname_buf = u64_to_user_ptr(bpf_dinfo.prog_ctx_type_name); 153 if (copy_to_user(tname_buf, prog_ctx_type_name, tname_len)) { 154 err = -EFAULT; 155 goto done; 156 } 157 158 /* copy potentially updated bpf_dinfo and info_len */ 159 if (copy_to_user(ubpf_dinfo, &bpf_dinfo, info_len) || 160 put_user(info_len, &uattr->info.info_len)) 161 return -EFAULT; 162 163 done: 164 fdput(qfd); 165 return err; 166 } 167 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org