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