diff options
Diffstat (limited to 'tools/objtool/check.c')
-rw-r--r-- | tools/objtool/check.c | 76 |
1 files changed, 38 insertions, 38 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 6e59e7f578ff..a1b14378bab0 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1225,12 +1225,15 @@ static const char *uaccess_safe_builtin[] = { "__ubsan_handle_load_invalid_value", /* STACKLEAK */ "stackleak_track_stack", + /* TRACE_BRANCH_PROFILING */ + "ftrace_likely_update", + /* STACKPROTECTOR */ + "__stack_chk_fail", /* misc */ "csum_partial_copy_generic", "copy_mc_fragile", "copy_mc_fragile_handle_tail", "copy_mc_enhanced_fast_string", - "ftrace_likely_update", /* CONFIG_TRACE_BRANCH_PROFILING */ "rep_stos_alternative", "rep_movs_alternative", "__copy_user_nocache", @@ -1549,6 +1552,8 @@ static int add_jump_destinations(struct objtool_file *file) unsigned long dest_off; for_each_insn(file, insn) { + struct symbol *func = insn_func(insn); + if (insn->jump_dest) { /* * handle_group_alt() may have previously set @@ -1572,7 +1577,7 @@ static int add_jump_destinations(struct objtool_file *file) } else if (reloc->sym->return_thunk) { add_return_call(file, insn, true); continue; - } else if (insn_func(insn)) { + } else if (func) { /* * External sibling call or internal sibling call with * STT_FUNC reloc. @@ -1605,6 +1610,15 @@ static int add_jump_destinations(struct objtool_file *file) continue; } + /* + * GCOV/KCOV dead code can jump to the end of the + * function/section. + */ + if (file->ignore_unreachables && func && + dest_sec == insn->sec && + dest_off == func->offset + func->len) + continue; + WARN_INSN(insn, "can't find jump dest instruction at %s+0x%lx", dest_sec->name, dest_off); return -1; @@ -1613,8 +1627,7 @@ static int add_jump_destinations(struct objtool_file *file) /* * Cross-function jump. */ - if (insn_func(insn) && insn_func(jump_dest) && - insn_func(insn) != insn_func(jump_dest)) { + if (func && insn_func(jump_dest) && func != insn_func(jump_dest)) { /* * For GCC 8+, create parent/child links for any cold @@ -1631,10 +1644,10 @@ static int add_jump_destinations(struct objtool_file *file) * case where the parent function's only reference to a * subfunction is through a jump table. */ - if (!strstr(insn_func(insn)->name, ".cold") && + if (!strstr(func->name, ".cold") && strstr(insn_func(jump_dest)->name, ".cold")) { - insn_func(insn)->cfunc = insn_func(jump_dest); - insn_func(jump_dest)->pfunc = insn_func(insn); + func->cfunc = insn_func(jump_dest); + insn_func(jump_dest)->pfunc = func; } } @@ -3569,6 +3582,9 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, !strncmp(func->name, "__pfx_", 6)) return 0; + if (file->ignore_unreachables) + return 0; + WARN("%s() falls through to next function %s()", func->name, insn_func(insn)->name); return 1; @@ -3788,6 +3804,9 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, if (!next_insn) { if (state.cfi.cfa.base == CFI_UNDEFINED) return 0; + if (file->ignore_unreachables) + return 0; + WARN("%s: unexpected end of section", sec->name); return 1; } @@ -3926,6 +3945,11 @@ static int validate_unret(struct objtool_file *file, struct instruction *insn) WARN_INSN(insn, "RET before UNTRAIN"); return 1; + case INSN_CONTEXT_SWITCH: + if (insn_func(insn)) + break; + return 0; + case INSN_NOP: if (insn->retpoline_safe) return 0; @@ -3935,6 +3959,9 @@ static int validate_unret(struct objtool_file *file, struct instruction *insn) break; } + if (insn->dead_end) + return 0; + if (!next) { WARN_INSN(insn, "teh end!"); return -1; @@ -4089,7 +4116,7 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio * It may also insert a UD2 after calling a __noreturn function. */ prev_insn = prev_insn_same_sec(file, insn); - if (prev_insn->dead_end && + if (prev_insn && prev_insn->dead_end && (insn->type == INSN_BUG || (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest && insn->jump_dest->type == INSN_BUG))) @@ -4511,35 +4538,6 @@ static int validate_sls(struct objtool_file *file) return warnings; } -static bool ignore_noreturn_call(struct instruction *insn) -{ - struct symbol *call_dest = insn_call_dest(insn); - - /* - * FIXME: hack, we need a real noreturn solution - * - * Problem is, exc_double_fault() may or may not return, depending on - * whether CONFIG_X86_ESPFIX64 is set. But objtool has no visibility - * to the kernel config. - * - * Other potential ways to fix it: - * - * - have compiler communicate __noreturn functions somehow - * - remove CONFIG_X86_ESPFIX64 - * - read the .config file - * - add a cmdline option - * - create a generic objtool annotation format (vs a bunch of custom - * formats) and annotate it - */ - if (!strcmp(call_dest->name, "exc_double_fault")) { - /* prevent further unreachable warnings for the caller */ - insn->sym->warned = 1; - return true; - } - - return false; -} - static int validate_reachable_instructions(struct objtool_file *file) { struct instruction *insn, *prev_insn; @@ -4556,7 +4554,7 @@ static int validate_reachable_instructions(struct objtool_file *file) prev_insn = prev_insn_same_sec(file, insn); if (prev_insn && prev_insn->dead_end) { call_dest = insn_call_dest(prev_insn); - if (call_dest && !ignore_noreturn_call(prev_insn)) { + if (call_dest) { WARN_INSN(insn, "%s() is missing a __noreturn annotation", call_dest->name); warnings++; @@ -4579,6 +4577,8 @@ static int disas_funcs(const char *funcs) char *cmd; cross_compile = getenv("CROSS_COMPILE"); + if (!cross_compile) + cross_compile = ""; objdump_str = "%sobjdump -wdr %s | gawk -M -v _funcs='%s' '" "BEGIN { split(_funcs, funcs); }" |