1 // SPDX-License-Identifier: GPL-2.0-or-later
2 #include <linux/objtool_types.h>
3 #include <asm/orc_types.h>
4
5 #include <objtool/check.h>
6 #include <objtool/orc.h>
7 #include <objtool/warn.h>
8 #include <objtool/endianness.h>
9
init_orc_entry(struct orc_entry * orc,struct cfi_state * cfi,struct instruction * insn)10 int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn)
11 {
12 struct cfi_reg *fp = &cfi->regs[CFI_FP];
13 struct cfi_reg *ra = &cfi->regs[CFI_RA];
14
15 memset(orc, 0, sizeof(*orc));
16
17 if (!cfi) {
18 /*
19 * This is usually either unreachable nops/traps (which don't
20 * trigger unreachable instruction warnings), or
21 * STACK_FRAME_NON_STANDARD functions.
22 */
23 orc->type = ORC_TYPE_UNDEFINED;
24 return 0;
25 }
26
27 switch (cfi->type) {
28 case UNWIND_HINT_TYPE_UNDEFINED:
29 orc->type = ORC_TYPE_UNDEFINED;
30 return 0;
31 case UNWIND_HINT_TYPE_END_OF_STACK:
32 orc->type = ORC_TYPE_END_OF_STACK;
33 return 0;
34 case UNWIND_HINT_TYPE_CALL:
35 orc->type = ORC_TYPE_CALL;
36 break;
37 case UNWIND_HINT_TYPE_REGS:
38 orc->type = ORC_TYPE_REGS;
39 break;
40 case UNWIND_HINT_TYPE_REGS_PARTIAL:
41 orc->type = ORC_TYPE_REGS_PARTIAL;
42 break;
43 default:
44 WARN_INSN(insn, "unknown unwind hint type %d", cfi->type);
45 return -1;
46 }
47
48 orc->signal = cfi->signal;
49
50 switch (cfi->cfa.base) {
51 case CFI_SP:
52 orc->sp_reg = ORC_REG_SP;
53 break;
54 case CFI_FP:
55 orc->sp_reg = ORC_REG_FP;
56 break;
57 default:
58 WARN_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
59 return -1;
60 }
61
62 switch (fp->base) {
63 case CFI_UNDEFINED:
64 orc->fp_reg = ORC_REG_UNDEFINED;
65 orc->fp_offset = 0;
66 break;
67 case CFI_CFA:
68 orc->fp_reg = ORC_REG_PREV_SP;
69 orc->fp_offset = fp->offset;
70 break;
71 case CFI_FP:
72 orc->fp_reg = ORC_REG_FP;
73 break;
74 default:
75 WARN_INSN(insn, "unknown FP base reg %d", fp->base);
76 return -1;
77 }
78
79 switch (ra->base) {
80 case CFI_UNDEFINED:
81 orc->ra_reg = ORC_REG_UNDEFINED;
82 orc->ra_offset = 0;
83 break;
84 case CFI_CFA:
85 orc->ra_reg = ORC_REG_PREV_SP;
86 orc->ra_offset = ra->offset;
87 break;
88 case CFI_FP:
89 orc->ra_reg = ORC_REG_FP;
90 break;
91 default:
92 WARN_INSN(insn, "unknown RA base reg %d", ra->base);
93 return -1;
94 }
95
96 orc->sp_offset = cfi->cfa.offset;
97
98 return 0;
99 }
100
write_orc_entry(struct elf * elf,struct section * orc_sec,struct section * ip_sec,unsigned int idx,struct section * insn_sec,unsigned long insn_off,struct orc_entry * o)101 int write_orc_entry(struct elf *elf, struct section *orc_sec,
102 struct section *ip_sec, unsigned int idx,
103 struct section *insn_sec, unsigned long insn_off,
104 struct orc_entry *o)
105 {
106 struct orc_entry *orc;
107
108 /* populate ORC data */
109 orc = (struct orc_entry *)orc_sec->data->d_buf + idx;
110 memcpy(orc, o, sizeof(*orc));
111
112 /* populate reloc for ip */
113 if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx,
114 insn_sec, insn_off))
115 return -1;
116
117 return 0;
118 }
119
reg_name(unsigned int reg)120 static const char *reg_name(unsigned int reg)
121 {
122 switch (reg) {
123 case ORC_REG_SP:
124 return "sp";
125 case ORC_REG_FP:
126 return "fp";
127 case ORC_REG_PREV_SP:
128 return "prevsp";
129 default:
130 return "?";
131 }
132 }
133
orc_type_name(unsigned int type)134 static const char *orc_type_name(unsigned int type)
135 {
136 switch (type) {
137 case UNWIND_HINT_TYPE_CALL:
138 return "call";
139 case UNWIND_HINT_TYPE_REGS:
140 return "regs";
141 case UNWIND_HINT_TYPE_REGS_PARTIAL:
142 return "regs (partial)";
143 default:
144 return "?";
145 }
146 }
147
print_reg(unsigned int reg,int offset)148 static void print_reg(unsigned int reg, int offset)
149 {
150 if (reg == ORC_REG_UNDEFINED)
151 printf(" (und) ");
152 else
153 printf("%s + %3d", reg_name(reg), offset);
154
155 }
156
orc_print_dump(struct elf * dummy_elf,struct orc_entry * orc,int i)157 void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i)
158 {
159 printf("type:%s", orc_type_name(orc[i].type));
160
161 printf(" sp:");
162 print_reg(orc[i].sp_reg, orc[i].sp_offset);
163
164 printf(" fp:");
165 print_reg(orc[i].fp_reg, orc[i].fp_offset);
166
167 printf(" ra:");
168 print_reg(orc[i].ra_reg, orc[i].ra_offset);
169
170 printf(" signal:%d\n", orc[i].signal);
171 }
172