orc_dump.c 4.1 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
  4. */
  5. #include <unistd.h>
  6. #include <linux/objtool.h>
  7. #include <asm/orc_types.h>
  8. #include "objtool.h"
  9. #include "warn.h"
  10. static const char *reg_name(unsigned int reg)
  11. {
  12. switch (reg) {
  13. case ORC_REG_PREV_SP:
  14. return "prevsp";
  15. case ORC_REG_DX:
  16. return "dx";
  17. case ORC_REG_DI:
  18. return "di";
  19. case ORC_REG_BP:
  20. return "bp";
  21. case ORC_REG_SP:
  22. return "sp";
  23. case ORC_REG_R10:
  24. return "r10";
  25. case ORC_REG_R13:
  26. return "r13";
  27. case ORC_REG_BP_INDIRECT:
  28. return "bp(ind)";
  29. case ORC_REG_SP_INDIRECT:
  30. return "sp(ind)";
  31. default:
  32. return "?";
  33. }
  34. }
  35. static const char *orc_type_name(unsigned int type)
  36. {
  37. switch (type) {
  38. case UNWIND_HINT_TYPE_CALL:
  39. return "call";
  40. case UNWIND_HINT_TYPE_REGS:
  41. return "regs";
  42. case UNWIND_HINT_TYPE_REGS_PARTIAL:
  43. return "regs (partial)";
  44. default:
  45. return "?";
  46. }
  47. }
  48. static void print_reg(unsigned int reg, int offset)
  49. {
  50. if (reg == ORC_REG_BP_INDIRECT)
  51. printf("(bp%+d)", offset);
  52. else if (reg == ORC_REG_SP_INDIRECT)
  53. printf("(sp%+d)", offset);
  54. else if (reg == ORC_REG_UNDEFINED)
  55. printf("(und)");
  56. else
  57. printf("%s%+d", reg_name(reg), offset);
  58. }
  59. int orc_dump(const char *_objname)
  60. {
  61. int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
  62. struct orc_entry *orc = NULL;
  63. char *name;
  64. size_t nr_sections;
  65. Elf64_Addr orc_ip_addr = 0;
  66. size_t shstrtab_idx, strtab_idx = 0;
  67. Elf *elf;
  68. Elf_Scn *scn;
  69. GElf_Shdr sh;
  70. GElf_Rela rela;
  71. GElf_Sym sym;
  72. Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
  73. objname = _objname;
  74. elf_version(EV_CURRENT);
  75. fd = open(objname, O_RDONLY);
  76. if (fd == -1) {
  77. perror("open");
  78. return -1;
  79. }
  80. elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
  81. if (!elf) {
  82. WARN_ELF("elf_begin");
  83. return -1;
  84. }
  85. if (elf_getshdrnum(elf, &nr_sections)) {
  86. WARN_ELF("elf_getshdrnum");
  87. return -1;
  88. }
  89. if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
  90. WARN_ELF("elf_getshdrstrndx");
  91. return -1;
  92. }
  93. for (i = 0; i < nr_sections; i++) {
  94. scn = elf_getscn(elf, i);
  95. if (!scn) {
  96. WARN_ELF("elf_getscn");
  97. return -1;
  98. }
  99. if (!gelf_getshdr(scn, &sh)) {
  100. WARN_ELF("gelf_getshdr");
  101. return -1;
  102. }
  103. name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
  104. if (!name) {
  105. WARN_ELF("elf_strptr");
  106. return -1;
  107. }
  108. data = elf_getdata(scn, NULL);
  109. if (!data) {
  110. WARN_ELF("elf_getdata");
  111. return -1;
  112. }
  113. if (!strcmp(name, ".symtab")) {
  114. symtab = data;
  115. } else if (!strcmp(name, ".strtab")) {
  116. strtab_idx = i;
  117. } else if (!strcmp(name, ".orc_unwind")) {
  118. orc = data->d_buf;
  119. orc_size = sh.sh_size;
  120. } else if (!strcmp(name, ".orc_unwind_ip")) {
  121. orc_ip = data->d_buf;
  122. orc_ip_addr = sh.sh_addr;
  123. } else if (!strcmp(name, ".rela.orc_unwind_ip")) {
  124. rela_orc_ip = data;
  125. }
  126. }
  127. if (!symtab || !strtab_idx || !orc || !orc_ip)
  128. return 0;
  129. if (orc_size % sizeof(*orc) != 0) {
  130. WARN("bad .orc_unwind section size");
  131. return -1;
  132. }
  133. nr_entries = orc_size / sizeof(*orc);
  134. for (i = 0; i < nr_entries; i++) {
  135. if (rela_orc_ip) {
  136. if (!gelf_getrela(rela_orc_ip, i, &rela)) {
  137. WARN_ELF("gelf_getrela");
  138. return -1;
  139. }
  140. if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
  141. WARN_ELF("gelf_getsym");
  142. return -1;
  143. }
  144. if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
  145. scn = elf_getscn(elf, sym.st_shndx);
  146. if (!scn) {
  147. WARN_ELF("elf_getscn");
  148. return -1;
  149. }
  150. if (!gelf_getshdr(scn, &sh)) {
  151. WARN_ELF("gelf_getshdr");
  152. return -1;
  153. }
  154. name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
  155. if (!name) {
  156. WARN_ELF("elf_strptr");
  157. return -1;
  158. }
  159. } else {
  160. name = elf_strptr(elf, strtab_idx, sym.st_name);
  161. if (!name) {
  162. WARN_ELF("elf_strptr");
  163. return -1;
  164. }
  165. }
  166. printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
  167. } else {
  168. printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
  169. }
  170. printf(" sp:");
  171. print_reg(orc[i].sp_reg, orc[i].sp_offset);
  172. printf(" bp:");
  173. print_reg(orc[i].bp_reg, orc[i].bp_offset);
  174. printf(" type:%s end:%d\n",
  175. orc_type_name(orc[i].type), orc[i].end);
  176. }
  177. elf_end(elf);
  178. close(fd);
  179. return 0;
  180. }