tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 88808fbbead481aedb46640a5ace69c58287f56a commit: 51c66ad849a703d9bbfd7704c941827aed0fd9fd powerpc/bpf: Implement extended BPF on PPC32 config: powerpc-randconfig-m031-20220130 (https://download.01.org/0day-ci/archive/20220204/202202040124.7MMKaXXV-lkp@intel.com/config ) compiler: powerpc-linux-gcc (GCC) 11.2.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot Reported-by: Dan Carpenter smatch warnings: arch/powerpc/net/bpf_jit_comp.c:225 bpf_int_jit_compile() error: uninitialized symbol 'pass'. vim +/pass +225 arch/powerpc/net/bpf_jit_comp.c 4ea76e90a97d22 Christophe Leroy 2021-03-22 88 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) 4ea76e90a97d22 Christophe Leroy 2021-03-22 89 { 4ea76e90a97d22 Christophe Leroy 2021-03-22 90 u32 proglen; 4ea76e90a97d22 Christophe Leroy 2021-03-22 91 u32 alloclen; 4ea76e90a97d22 Christophe Leroy 2021-03-22 92 u8 *image = NULL; 4ea76e90a97d22 Christophe Leroy 2021-03-22 93 u32 *code_base; 4ea76e90a97d22 Christophe Leroy 2021-03-22 94 u32 *addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 95 struct powerpc64_jit_data *jit_data; 4ea76e90a97d22 Christophe Leroy 2021-03-22 96 struct codegen_context cgctx; 4ea76e90a97d22 Christophe Leroy 2021-03-22 97 int pass; ^^^^^^^^ 4ea76e90a97d22 Christophe Leroy 2021-03-22 98 int flen; 4ea76e90a97d22 Christophe Leroy 2021-03-22 99 struct bpf_binary_header *bpf_hdr; 4ea76e90a97d22 Christophe Leroy 2021-03-22 100 struct bpf_prog *org_fp = fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 101 struct bpf_prog *tmp_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 102 bool bpf_blinded = false; 4ea76e90a97d22 Christophe Leroy 2021-03-22 103 bool extra_pass = false; 4ea76e90a97d22 Christophe Leroy 2021-03-22 104 4ea76e90a97d22 Christophe Leroy 2021-03-22 105 if (!fp->jit_requested) 4ea76e90a97d22 Christophe Leroy 2021-03-22 106 return org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 107 4ea76e90a97d22 Christophe Leroy 2021-03-22 108 tmp_fp = bpf_jit_blind_constants(org_fp); 4ea76e90a97d22 Christophe Leroy 2021-03-22 109 if (IS_ERR(tmp_fp)) 4ea76e90a97d22 Christophe Leroy 2021-03-22 110 return org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 111 4ea76e90a97d22 Christophe Leroy 2021-03-22 112 if (tmp_fp != org_fp) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 113 bpf_blinded = true; 4ea76e90a97d22 Christophe Leroy 2021-03-22 114 fp = tmp_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 115 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 116 4ea76e90a97d22 Christophe Leroy 2021-03-22 117 jit_data = fp->aux->jit_data; 4ea76e90a97d22 Christophe Leroy 2021-03-22 118 if (!jit_data) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 119 jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); 4ea76e90a97d22 Christophe Leroy 2021-03-22 120 if (!jit_data) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 121 fp = org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 122 goto out; 4ea76e90a97d22 Christophe Leroy 2021-03-22 123 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 124 fp->aux->jit_data = jit_data; 4ea76e90a97d22 Christophe Leroy 2021-03-22 125 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 126 4ea76e90a97d22 Christophe Leroy 2021-03-22 127 flen = fp->len; 4ea76e90a97d22 Christophe Leroy 2021-03-22 128 addrs = jit_data->addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 129 if (addrs) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 130 cgctx = jit_data->ctx; 4ea76e90a97d22 Christophe Leroy 2021-03-22 131 image = jit_data->image; 4ea76e90a97d22 Christophe Leroy 2021-03-22 132 bpf_hdr = jit_data->header; 4ea76e90a97d22 Christophe Leroy 2021-03-22 133 proglen = jit_data->proglen; 4ea76e90a97d22 Christophe Leroy 2021-03-22 134 alloclen = proglen + FUNCTION_DESCR_SIZE; 4ea76e90a97d22 Christophe Leroy 2021-03-22 135 extra_pass = true; 4ea76e90a97d22 Christophe Leroy 2021-03-22 136 goto skip_init_ctx; Assume we hit this goto 4ea76e90a97d22 Christophe Leroy 2021-03-22 137 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 138 4ea76e90a97d22 Christophe Leroy 2021-03-22 139 addrs = kcalloc(flen + 1, sizeof(*addrs), GFP_KERNEL); 4ea76e90a97d22 Christophe Leroy 2021-03-22 140 if (addrs == NULL) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 141 fp = org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 142 goto out_addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 143 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 144 4ea76e90a97d22 Christophe Leroy 2021-03-22 145 memset(&cgctx, 0, sizeof(struct codegen_context)); 4ea76e90a97d22 Christophe Leroy 2021-03-22 146 4ea76e90a97d22 Christophe Leroy 2021-03-22 147 /* Make sure that the stack is quadword aligned. */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 148 cgctx.stack_size = round_up(fp->aux->stack_depth, 16); 4ea76e90a97d22 Christophe Leroy 2021-03-22 149 4ea76e90a97d22 Christophe Leroy 2021-03-22 150 /* Scouting faux-generate pass 0 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 151 if (bpf_jit_build_body(fp, 0, &cgctx, addrs, false)) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 152 /* We hit something illegal or unsupported. */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 153 fp = org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 154 goto out_addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 155 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 156 4ea76e90a97d22 Christophe Leroy 2021-03-22 157 /* 4ea76e90a97d22 Christophe Leroy 2021-03-22 158 * If we have seen a tail call, we need a second pass. 4ea76e90a97d22 Christophe Leroy 2021-03-22 159 * This is because bpf_jit_emit_common_epilogue() is called 4ea76e90a97d22 Christophe Leroy 2021-03-22 160 * from bpf_jit_emit_tail_call() with a not yet stable ctx->seen. 4ea76e90a97d22 Christophe Leroy 2021-03-22 161 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 162 if (cgctx.seen & SEEN_TAILCALL) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 163 cgctx.idx = 0; 4ea76e90a97d22 Christophe Leroy 2021-03-22 164 if (bpf_jit_build_body(fp, 0, &cgctx, addrs, false)) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 165 fp = org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 166 goto out_addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 167 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 168 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 169 4ea76e90a97d22 Christophe Leroy 2021-03-22 170 /* 4ea76e90a97d22 Christophe Leroy 2021-03-22 171 * Pretend to build prologue, given the features we've seen. This will 4ea76e90a97d22 Christophe Leroy 2021-03-22 172 * update ctgtx.idx as it pretends to output instructions, then we can 4ea76e90a97d22 Christophe Leroy 2021-03-22 173 * calculate total size from idx. 4ea76e90a97d22 Christophe Leroy 2021-03-22 174 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 175 bpf_jit_build_prologue(0, &cgctx); 4ea76e90a97d22 Christophe Leroy 2021-03-22 176 bpf_jit_build_epilogue(0, &cgctx); 4ea76e90a97d22 Christophe Leroy 2021-03-22 177 4ea76e90a97d22 Christophe Leroy 2021-03-22 178 proglen = cgctx.idx * 4; 4ea76e90a97d22 Christophe Leroy 2021-03-22 179 alloclen = proglen + FUNCTION_DESCR_SIZE; 4ea76e90a97d22 Christophe Leroy 2021-03-22 180 4ea76e90a97d22 Christophe Leroy 2021-03-22 181 bpf_hdr = bpf_jit_binary_alloc(alloclen, &image, 4, bpf_jit_fill_ill_insns); 4ea76e90a97d22 Christophe Leroy 2021-03-22 182 if (!bpf_hdr) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 183 fp = org_fp; 4ea76e90a97d22 Christophe Leroy 2021-03-22 184 goto out_addrs; 4ea76e90a97d22 Christophe Leroy 2021-03-22 185 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 186 4ea76e90a97d22 Christophe Leroy 2021-03-22 187 skip_init_ctx: 4ea76e90a97d22 Christophe Leroy 2021-03-22 188 code_base = (u32 *)(image + FUNCTION_DESCR_SIZE); 4ea76e90a97d22 Christophe Leroy 2021-03-22 189 4ea76e90a97d22 Christophe Leroy 2021-03-22 190 if (extra_pass) { 4ea76e90a97d22 Christophe Leroy 2021-03-22 191 /* 4ea76e90a97d22 Christophe Leroy 2021-03-22 192 * Do not touch the prologue and epilogue as they will remain 4ea76e90a97d22 Christophe Leroy 2021-03-22 193 * unchanged. Only fix the branch target address for subprog 4ea76e90a97d22 Christophe Leroy 2021-03-22 194 * calls in the body. 4ea76e90a97d22 Christophe Leroy 2021-03-22 195 * 4ea76e90a97d22 Christophe Leroy 2021-03-22 196 * This does not change the offsets and lengths of the subprog 4ea76e90a97d22 Christophe Leroy 2021-03-22 197 * call instruction sequences and hence, the size of the JITed 4ea76e90a97d22 Christophe Leroy 2021-03-22 198 * image as well. 4ea76e90a97d22 Christophe Leroy 2021-03-22 199 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 200 bpf_jit_fixup_subprog_calls(fp, code_base, &cgctx, addrs); 4ea76e90a97d22 Christophe Leroy 2021-03-22 201 4ea76e90a97d22 Christophe Leroy 2021-03-22 202 /* There is no need to perform the usual passes. */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 203 goto skip_codegen_passes; Goto before pass is inintialized 4ea76e90a97d22 Christophe Leroy 2021-03-22 204 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 205 4ea76e90a97d22 Christophe Leroy 2021-03-22 206 /* Code generation passes 1-2 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 207 for (pass = 1; pass < 3; pass++) { ^^^^^^^^ Here 4ea76e90a97d22 Christophe Leroy 2021-03-22 208 /* Now build the prologue, body code & epilogue for real. */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 209 cgctx.idx = 0; 4ea76e90a97d22 Christophe Leroy 2021-03-22 210 bpf_jit_build_prologue(code_base, &cgctx); 4ea76e90a97d22 Christophe Leroy 2021-03-22 211 bpf_jit_build_body(fp, code_base, &cgctx, addrs, extra_pass); 4ea76e90a97d22 Christophe Leroy 2021-03-22 212 bpf_jit_build_epilogue(code_base, &cgctx); 4ea76e90a97d22 Christophe Leroy 2021-03-22 213 4ea76e90a97d22 Christophe Leroy 2021-03-22 214 if (bpf_jit_enable > 1) 4ea76e90a97d22 Christophe Leroy 2021-03-22 215 pr_info("Pass %d: shrink = %d, seen = 0x%x\n", pass, 4ea76e90a97d22 Christophe Leroy 2021-03-22 216 proglen - (cgctx.idx * 4), cgctx.seen); 4ea76e90a97d22 Christophe Leroy 2021-03-22 217 } 4ea76e90a97d22 Christophe Leroy 2021-03-22 218 4ea76e90a97d22 Christophe Leroy 2021-03-22 219 skip_codegen_passes: 4ea76e90a97d22 Christophe Leroy 2021-03-22 220 if (bpf_jit_enable > 1) 4ea76e90a97d22 Christophe Leroy 2021-03-22 221 /* 4ea76e90a97d22 Christophe Leroy 2021-03-22 222 * Note that we output the base address of the code_base 4ea76e90a97d22 Christophe Leroy 2021-03-22 223 * rather than image, since opcodes are in code_base. 4ea76e90a97d22 Christophe Leroy 2021-03-22 224 */ 4ea76e90a97d22 Christophe Leroy 2021-03-22 @225 bpf_jit_dump(flen, proglen, pass, code_base); ^^^^ Uninitialized. 4ea76e90a97d22 Christophe Leroy 2021-03-22 226 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org _______________________________________________ kbuild mailing list -- kbuild@lists.01.org To unsubscribe send an email to kbuild-leave@lists.01.org