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6#include <unistd.h>
7#include <linux/objtool.h>
8#include <asm/orc_types.h>
9#include "objtool.h"
10#include "warn.h"
11
12static const char *reg_name(unsigned int reg)
13{
14 switch (reg) {
15 case ORC_REG_PREV_SP:
16 return "prevsp";
17 case ORC_REG_DX:
18 return "dx";
19 case ORC_REG_DI:
20 return "di";
21 case ORC_REG_BP:
22 return "bp";
23 case ORC_REG_SP:
24 return "sp";
25 case ORC_REG_R10:
26 return "r10";
27 case ORC_REG_R13:
28 return "r13";
29 case ORC_REG_BP_INDIRECT:
30 return "bp(ind)";
31 case ORC_REG_SP_INDIRECT:
32 return "sp(ind)";
33 default:
34 return "?";
35 }
36}
37
38static const char *orc_type_name(unsigned int type)
39{
40 switch (type) {
41 case UNWIND_HINT_TYPE_CALL:
42 return "call";
43 case UNWIND_HINT_TYPE_REGS:
44 return "regs";
45 case UNWIND_HINT_TYPE_REGS_PARTIAL:
46 return "regs (partial)";
47 default:
48 return "?";
49 }
50}
51
52static void print_reg(unsigned int reg, int offset)
53{
54 if (reg == ORC_REG_BP_INDIRECT)
55 printf("(bp%+d)", offset);
56 else if (reg == ORC_REG_SP_INDIRECT)
57 printf("(sp%+d)", offset);
58 else if (reg == ORC_REG_UNDEFINED)
59 printf("(und)");
60 else
61 printf("%s%+d", reg_name(reg), offset);
62}
63
64int orc_dump(const char *_objname)
65{
66 int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
67 struct orc_entry *orc = NULL;
68 char *name;
69 size_t nr_sections;
70 Elf64_Addr orc_ip_addr = 0;
71 size_t shstrtab_idx, strtab_idx = 0;
72 Elf *elf;
73 Elf_Scn *scn;
74 GElf_Shdr sh;
75 GElf_Rela rela;
76 GElf_Sym sym;
77 Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
78
79
80 objname = _objname;
81
82 elf_version(EV_CURRENT);
83
84 fd = open(objname, O_RDONLY);
85 if (fd == -1) {
86 perror("open");
87 return -1;
88 }
89
90 elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
91 if (!elf) {
92 WARN_ELF("elf_begin");
93 return -1;
94 }
95
96 if (elf_getshdrnum(elf, &nr_sections)) {
97 WARN_ELF("elf_getshdrnum");
98 return -1;
99 }
100
101 if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
102 WARN_ELF("elf_getshdrstrndx");
103 return -1;
104 }
105
106 for (i = 0; i < nr_sections; i++) {
107 scn = elf_getscn(elf, i);
108 if (!scn) {
109 WARN_ELF("elf_getscn");
110 return -1;
111 }
112
113 if (!gelf_getshdr(scn, &sh)) {
114 WARN_ELF("gelf_getshdr");
115 return -1;
116 }
117
118 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
119 if (!name) {
120 WARN_ELF("elf_strptr");
121 return -1;
122 }
123
124 data = elf_getdata(scn, NULL);
125 if (!data) {
126 WARN_ELF("elf_getdata");
127 return -1;
128 }
129
130 if (!strcmp(name, ".symtab")) {
131 symtab = data;
132 } else if (!strcmp(name, ".strtab")) {
133 strtab_idx = i;
134 } else if (!strcmp(name, ".orc_unwind")) {
135 orc = data->d_buf;
136 orc_size = sh.sh_size;
137 } else if (!strcmp(name, ".orc_unwind_ip")) {
138 orc_ip = data->d_buf;
139 orc_ip_addr = sh.sh_addr;
140 } else if (!strcmp(name, ".rela.orc_unwind_ip")) {
141 rela_orc_ip = data;
142 }
143 }
144
145 if (!symtab || !strtab_idx || !orc || !orc_ip)
146 return 0;
147
148 if (orc_size % sizeof(*orc) != 0) {
149 WARN("bad .orc_unwind section size");
150 return -1;
151 }
152
153 nr_entries = orc_size / sizeof(*orc);
154 for (i = 0; i < nr_entries; i++) {
155 if (rela_orc_ip) {
156 if (!gelf_getrela(rela_orc_ip, i, &rela)) {
157 WARN_ELF("gelf_getrela");
158 return -1;
159 }
160
161 if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
162 WARN_ELF("gelf_getsym");
163 return -1;
164 }
165
166 if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
167 scn = elf_getscn(elf, sym.st_shndx);
168 if (!scn) {
169 WARN_ELF("elf_getscn");
170 return -1;
171 }
172
173 if (!gelf_getshdr(scn, &sh)) {
174 WARN_ELF("gelf_getshdr");
175 return -1;
176 }
177
178 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
179 if (!name) {
180 WARN_ELF("elf_strptr");
181 return -1;
182 }
183 } else {
184 name = elf_strptr(elf, strtab_idx, sym.st_name);
185 if (!name) {
186 WARN_ELF("elf_strptr");
187 return -1;
188 }
189 }
190
191 printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
192
193 } else {
194 printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
195 }
196
197
198 printf(" sp:");
199
200 print_reg(orc[i].sp_reg, orc[i].sp_offset);
201
202 printf(" bp:");
203
204 print_reg(orc[i].bp_reg, orc[i].bp_offset);
205
206 printf(" type:%s end:%d\n",
207 orc_type_name(orc[i].type), orc[i].end);
208 }
209
210 elf_end(elf);
211 close(fd);
212
213 return 0;
214}
215
