Hi "Naveen, I love your patch! Perhaps something to improve:
[auto build test WARNING on bpf-next/master] [also build test WARNING on v5.2-rc4 next-20190613] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Naveen-N-Rao/bpf-optimize-constant-blinding/20190614-023948 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master reproduce: # apt-get install sparse # sparse version: v0.6.1-rc1-7-g2b96cd8-dirty make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag Reported-by: kbuild test robot <l...@intel.com> sparse warnings: (new ones prefixed by >>) kernel/bpf/core.c:210:49: sparse: sparse: arithmetics on pointers to functions include/linux/rbtree.h:120:9: sparse: sparse: incompatible types in comparison expression (different address spaces): include/linux/rbtree.h:120:9: sparse: struct rb_node [noderef] <asn:4> * include/linux/rbtree.h:120:9: sparse: struct rb_node * include/linux/rbtree.h:120:9: sparse: sparse: incompatible types in comparison expression (different address spaces): include/linux/rbtree.h:120:9: sparse: struct rb_node [noderef] <asn:4> * include/linux/rbtree.h:120:9: sparse: struct rb_node * >> kernel/bpf/core.c:1122:59: sparse: sparse: Using plain integer as NULL >> pointer kernel/bpf/core.c:1122:62: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:28:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:53:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:111:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:126:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:161:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:196:1: sparse: sparse: Using plain integer as NULL pointer include/trace/events/xdp.h:231:1: sparse: sparse: Using plain integer as NULL pointer vim +1122 kernel/bpf/core.c 1101 1102 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) 1103 { 1104 int i, j, rewritten, new_len, insn_cnt, ret = 0; 1105 struct bpf_insn insn_buff[16], aux[2]; 1106 struct bpf_prog *clone, *tmp; 1107 struct bpf_insn *insn; 1108 u32 *clone_index; 1109 1110 if (!bpf_jit_blinding_enabled(prog) || prog->blinded) 1111 return prog; 1112 1113 /* Dry run to figure out the final number of instructions */ 1114 clone_index = vmalloc(prog->len * sizeof(u32)); 1115 if (!clone_index) 1116 return ERR_PTR(-ENOMEM); 1117 1118 insn_cnt = prog->len; 1119 insn = prog->insnsi; 1120 rewritten = 0; 1121 for (i = 0; i < insn_cnt; i++, insn++) { > 1122 clone_index[i] = bpf_jit_blind_insn(insn, 0, 0); 1123 if (clone_index[i] > 1) 1124 rewritten += clone_index[i] - 1; 1125 } 1126 1127 if (rewritten) { 1128 /* Needs new allocation, branch adjustment, et al... */ 1129 clone = bpf_prog_clone_create(prog, GFP_USER); 1130 if (!clone) { 1131 ret = -ENOMEM; 1132 goto err; 1133 } 1134 1135 new_len = prog->len + rewritten; 1136 tmp = bpf_prog_realloc(clone, bpf_prog_size(new_len), GFP_USER); 1137 if (!tmp) { 1138 ret = -ENOMEM; 1139 goto err; 1140 } 1141 clone = tmp; 1142 clone->len = new_len; 1143 1144 /* rewrite instructions with constant blinding */ 1145 insn_cnt = prog->len; 1146 insn = prog->insnsi; 1147 for (i = 0, j = 0; i < insn_cnt; i++, j++, insn++) { 1148 /* capture new instruction index in clone_index */ 1149 clone_index[i] = j; 1150 1151 /* We temporarily need to hold the original ld64 insn 1152 * so that we can still access the first part in the 1153 * second blinding run. 1154 */ 1155 if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW) && 1156 insn[1].code == 0) 1157 memcpy(aux, insn, sizeof(aux)); 1158 1159 rewritten = bpf_jit_blind_insn(insn, aux, insn_buff); 1160 if (!rewritten) { 1161 memcpy(clone->insnsi + j, insn, 1162 sizeof(struct bpf_insn)); 1163 } else { 1164 memcpy(clone->insnsi + j, insn_buff, 1165 sizeof(struct bpf_insn) * rewritten); 1166 j += rewritten - 1; 1167 } 1168 } 1169 1170 /* adjust branches */ 1171 for (i = 0; i < insn_cnt; i++) { 1172 int next_insn_idx = clone->len; 1173 1174 if (i < insn_cnt - 1) 1175 next_insn_idx = clone_index[i + 1]; 1176 1177 insn = clone->insnsi + clone_index[i]; 1178 for (j = clone_index[i]; j < next_insn_idx; j++, insn++) { 1179 ret = bpf_jit_blind_adj_imm_off(insn, i, j, clone_index); 1180 if (ret) { 1181 goto err; 1182 } 1183 } 1184 } 1185 1186 /* adjust linfo */ 1187 if (clone->aux->nr_linfo) { 1188 struct bpf_line_info *linfo = clone->aux->linfo; 1189 1190 for (i = 0; i < clone->aux->nr_linfo; i++) 1191 linfo[i].insn_off = clone_index[linfo[i].insn_off]; 1192 } 1193 } else { 1194 /* if prog length remains same, not much work to do */ 1195 clone = bpf_prog_clone_create(prog, GFP_USER); 1196 if (!clone) { 1197 ret = -ENOMEM; 1198 goto err; 1199 } 1200 1201 insn_cnt = clone->len; 1202 insn = clone->insnsi; 1203 1204 for (i = 0; i < insn_cnt; i++, insn++) { 1205 if (clone_index[i]) { 1206 bpf_jit_blind_insn(insn, aux, insn_buff); 1207 memcpy(insn, insn_buff, sizeof(struct bpf_insn)); 1208 } 1209 } 1210 } 1211 1212 clone->blinded = 1; 1213 1214 err: 1215 vfree(clone_index); 1216 1217 if (ret) { 1218 if (clone) 1219 bpf_jit_prog_release_other(prog, clone); 1220 return ERR_PTR(ret); 1221 } 1222 1223 return clone; 1224 } 1225 #endif /* CONFIG_BPF_JIT */ 1226 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
