diff options
-rw-r--r-- | tools/objtool/check.c | 86 |
1 files changed, 55 insertions, 31 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5264a305d658..8118361295dd 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -515,7 +515,8 @@ static int add_jump_destinations(struct objtool_file *file) continue; } else { /* sibling call */ - insn->jump_dest = 0; + insn->call_dest = rela->sym; + insn->jump_dest = NULL; continue; } @@ -537,25 +538,38 @@ static int add_jump_destinations(struct objtool_file *file) } /* - * For GCC 8+, create parent/child links for any cold - * subfunctions. This is _mostly_ redundant with a similar - * initialization in read_symbols(). - * - * If a function has aliases, we want the *first* such function - * in the symbol table to be the subfunction's parent. In that - * case we overwrite the initialization done in read_symbols(). - * - * However this code can't completely replace the - * read_symbols() code because this doesn't detect the case - * where the parent function's only reference to a subfunction - * is through a switch table. + * Cross-function jump. */ if (insn->func && insn->jump_dest->func && - insn->func != insn->jump_dest->func && - !strstr(insn->func->name, ".cold.") && - strstr(insn->jump_dest->func->name, ".cold.")) { - insn->func->cfunc = insn->jump_dest->func; - insn->jump_dest->func->pfunc = insn->func; + insn->func != insn->jump_dest->func) { + + /* + * For GCC 8+, create parent/child links for any cold + * subfunctions. This is _mostly_ redundant with a + * similar initialization in read_symbols(). + * + * If a function has aliases, we want the *first* such + * function in the symbol table to be the subfunction's + * parent. In that case we overwrite the + * initialization done in read_symbols(). + * + * However this code can't completely replace the + * read_symbols() code because this doesn't detect the + * case where the parent function's only reference to a + * subfunction is through a switch table. + */ + if (!strstr(insn->func->name, ".cold.") && + strstr(insn->jump_dest->func->name, ".cold.")) { + insn->func->cfunc = insn->jump_dest->func; + insn->jump_dest->func->pfunc = insn->func; + + } else if (insn->jump_dest->func->pfunc != insn->func->pfunc && + insn->jump_dest->offset == insn->jump_dest->func->offset) { + + /* sibling class */ + insn->call_dest = insn->jump_dest->func; + insn->jump_dest = NULL; + } } } @@ -1785,6 +1799,17 @@ static bool insn_state_match(struct instruction *insn, struct insn_state *state) return false; } +static int validate_sibling_call(struct instruction *insn, struct insn_state *state) +{ + if (has_modified_stack_frame(state)) { + WARN_FUNC("sibling call from callable instruction with modified stack frame", + insn->sec, insn->offset); + return 1; + } + + return 0; +} + /* * Follow the branch starting at the given instruction, and recursively follow * any other branches (jumps). Meanwhile, track the frame pointer state at @@ -1935,9 +1960,14 @@ static int validate_branch(struct objtool_file *file, struct instruction *first, case INSN_JUMP_CONDITIONAL: case INSN_JUMP_UNCONDITIONAL: - if (insn->jump_dest && - (!func || !insn->jump_dest->func || - insn->jump_dest->func->pfunc == func)) { + if (func && !insn->jump_dest) { + ret = validate_sibling_call(insn, &state); + if (ret) + return ret; + + } else if (insn->jump_dest && + (!func || !insn->jump_dest->func || + insn->jump_dest->func->pfunc == func)) { ret = validate_branch(file, insn->jump_dest, state); if (ret) { @@ -1945,11 +1975,6 @@ static int validate_branch(struct objtool_file *file, struct instruction *first, BT_FUNC("(branch)", insn); return ret; } - - } else if (func && has_modified_stack_frame(&state)) { - WARN_FUNC("sibling call from callable instruction with modified stack frame", - sec, insn->offset); - return 1; } if (insn->type == INSN_JUMP_UNCONDITIONAL) @@ -1958,11 +1983,10 @@ static int validate_branch(struct objtool_file *file, struct instruction *first, break; case INSN_JUMP_DYNAMIC: - if (func && list_empty(&insn->alts) && - has_modified_stack_frame(&state)) { - WARN_FUNC("sibling call from callable instruction with modified stack frame", - sec, insn->offset); - return 1; + if (func && list_empty(&insn->alts)) { + ret = validate_sibling_call(insn, &state); + if (ret) + return ret; } return 0; |