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0006 #include <unistd.h>
0007 #include <linux/objtool.h>
0008 #include <asm/orc_types.h>
0009 #include <objtool/objtool.h>
0010 #include <objtool/warn.h>
0011 #include <objtool/endianness.h>
0012
0013 static const char *reg_name(unsigned int reg)
0014 {
0015 switch (reg) {
0016 case ORC_REG_PREV_SP:
0017 return "prevsp";
0018 case ORC_REG_DX:
0019 return "dx";
0020 case ORC_REG_DI:
0021 return "di";
0022 case ORC_REG_BP:
0023 return "bp";
0024 case ORC_REG_SP:
0025 return "sp";
0026 case ORC_REG_R10:
0027 return "r10";
0028 case ORC_REG_R13:
0029 return "r13";
0030 case ORC_REG_BP_INDIRECT:
0031 return "bp(ind)";
0032 case ORC_REG_SP_INDIRECT:
0033 return "sp(ind)";
0034 default:
0035 return "?";
0036 }
0037 }
0038
0039 static const char *orc_type_name(unsigned int type)
0040 {
0041 switch (type) {
0042 case UNWIND_HINT_TYPE_CALL:
0043 return "call";
0044 case UNWIND_HINT_TYPE_REGS:
0045 return "regs";
0046 case UNWIND_HINT_TYPE_REGS_PARTIAL:
0047 return "regs (partial)";
0048 default:
0049 return "?";
0050 }
0051 }
0052
0053 static void print_reg(unsigned int reg, int offset)
0054 {
0055 if (reg == ORC_REG_BP_INDIRECT)
0056 printf("(bp%+d)", offset);
0057 else if (reg == ORC_REG_SP_INDIRECT)
0058 printf("(sp)%+d", offset);
0059 else if (reg == ORC_REG_UNDEFINED)
0060 printf("(und)");
0061 else
0062 printf("%s%+d", reg_name(reg), offset);
0063 }
0064
0065 int orc_dump(const char *_objname)
0066 {
0067 int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
0068 struct orc_entry *orc = NULL;
0069 char *name;
0070 size_t nr_sections;
0071 Elf64_Addr orc_ip_addr = 0;
0072 size_t shstrtab_idx, strtab_idx = 0;
0073 Elf *elf;
0074 Elf_Scn *scn;
0075 GElf_Shdr sh;
0076 GElf_Rela rela;
0077 GElf_Sym sym;
0078 Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
0079
0080
0081 objname = _objname;
0082
0083 elf_version(EV_CURRENT);
0084
0085 fd = open(objname, O_RDONLY);
0086 if (fd == -1) {
0087 perror("open");
0088 return -1;
0089 }
0090
0091 elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
0092 if (!elf) {
0093 WARN_ELF("elf_begin");
0094 return -1;
0095 }
0096
0097 if (elf_getshdrnum(elf, &nr_sections)) {
0098 WARN_ELF("elf_getshdrnum");
0099 return -1;
0100 }
0101
0102 if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
0103 WARN_ELF("elf_getshdrstrndx");
0104 return -1;
0105 }
0106
0107 for (i = 0; i < nr_sections; i++) {
0108 scn = elf_getscn(elf, i);
0109 if (!scn) {
0110 WARN_ELF("elf_getscn");
0111 return -1;
0112 }
0113
0114 if (!gelf_getshdr(scn, &sh)) {
0115 WARN_ELF("gelf_getshdr");
0116 return -1;
0117 }
0118
0119 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
0120 if (!name) {
0121 WARN_ELF("elf_strptr");
0122 return -1;
0123 }
0124
0125 data = elf_getdata(scn, NULL);
0126 if (!data) {
0127 WARN_ELF("elf_getdata");
0128 return -1;
0129 }
0130
0131 if (!strcmp(name, ".symtab")) {
0132 symtab = data;
0133 } else if (!strcmp(name, ".strtab")) {
0134 strtab_idx = i;
0135 } else if (!strcmp(name, ".orc_unwind")) {
0136 orc = data->d_buf;
0137 orc_size = sh.sh_size;
0138 } else if (!strcmp(name, ".orc_unwind_ip")) {
0139 orc_ip = data->d_buf;
0140 orc_ip_addr = sh.sh_addr;
0141 } else if (!strcmp(name, ".rela.orc_unwind_ip")) {
0142 rela_orc_ip = data;
0143 }
0144 }
0145
0146 if (!symtab || !strtab_idx || !orc || !orc_ip)
0147 return 0;
0148
0149 if (orc_size % sizeof(*orc) != 0) {
0150 WARN("bad .orc_unwind section size");
0151 return -1;
0152 }
0153
0154 nr_entries = orc_size / sizeof(*orc);
0155 for (i = 0; i < nr_entries; i++) {
0156 if (rela_orc_ip) {
0157 if (!gelf_getrela(rela_orc_ip, i, &rela)) {
0158 WARN_ELF("gelf_getrela");
0159 return -1;
0160 }
0161
0162 if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
0163 WARN_ELF("gelf_getsym");
0164 return -1;
0165 }
0166
0167 if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
0168 scn = elf_getscn(elf, sym.st_shndx);
0169 if (!scn) {
0170 WARN_ELF("elf_getscn");
0171 return -1;
0172 }
0173
0174 if (!gelf_getshdr(scn, &sh)) {
0175 WARN_ELF("gelf_getshdr");
0176 return -1;
0177 }
0178
0179 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
0180 if (!name) {
0181 WARN_ELF("elf_strptr");
0182 return -1;
0183 }
0184 } else {
0185 name = elf_strptr(elf, strtab_idx, sym.st_name);
0186 if (!name) {
0187 WARN_ELF("elf_strptr");
0188 return -1;
0189 }
0190 }
0191
0192 printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
0193
0194 } else {
0195 printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
0196 }
0197
0198
0199 printf(" sp:");
0200
0201 print_reg(orc[i].sp_reg, bswap_if_needed(orc[i].sp_offset));
0202
0203 printf(" bp:");
0204
0205 print_reg(orc[i].bp_reg, bswap_if_needed(orc[i].bp_offset));
0206
0207 printf(" type:%s end:%d\n",
0208 orc_type_name(orc[i].type), orc[i].end);
0209 }
0210
0211 elf_end(elf);
0212 close(fd);
0213
0214 return 0;
0215 }
