Inline section_reference_needed() and is_reloc_allowed() into convert_reloc_sym() and remove the redundant is_reloc_allowed() check in clone_reloc().
Move the is_sec_sym() checks into the convert callees so they become no-ops when the reloc is already in the right format. This allows convert_reloc_sym() to unconditionally dispatch to the right converter based on section type. Signed-off-by: Josh Poimboeuf <[email protected]> --- tools/objtool/klp-diff.c | 76 +++++++++++++++------------------------- 1 file changed, 28 insertions(+), 48 deletions(-) diff --git a/tools/objtool/klp-diff.c b/tools/objtool/klp-diff.c index 19bc811db396..78633c9b68eb 100644 --- a/tools/objtool/klp-diff.c +++ b/tools/objtool/klp-diff.c @@ -838,39 +838,6 @@ static int clone_included_functions(struct elfs *e) return 0; } -/* - * Determine whether a relocation should reference the section rather than the - * underlying symbol. - */ -static bool section_reference_needed(struct section *sec) -{ - /* - * String symbols are zero-length and uncorrelated. It's easier to - * deal with them as section symbols. - */ - if (is_string_sec(sec)) - return true; - - /* - * .rodata has mostly anonymous data so there's no way to determine the - * length of a needed reference. just copy the whole section if needed. - */ - if (strstarts(sec->name, ".rodata")) - return true; - - /* UBSAN anonymous data */ - if (strstarts(sec->name, ".data..Lubsan") || /* GCC */ - strstarts(sec->name, ".data..L__unnamed_")) /* Clang */ - return true; - - return false; -} - -static bool is_reloc_allowed(struct reloc *reloc) -{ - return section_reference_needed(reloc->sym->sec) == is_sec_sym(reloc->sym); -} - static struct export *find_export(struct symbol *sym) { struct export *export; @@ -979,11 +946,15 @@ static bool klp_reloc_needed(struct reloc *patched_reloc) return true; } +/* Return -1 error, 0 success, 1 skip */ static int convert_reloc_sym_to_secsym(struct elf *elf, struct reloc *reloc) { struct symbol *sym = reloc->sym; struct section *sec = sym->sec; + if (is_sec_sym(sym)) + return 0; + if (!sec->sym && !elf_create_section_symbol(elf, sec)) return -1; @@ -993,11 +964,15 @@ static int convert_reloc_sym_to_secsym(struct elf *elf, struct reloc *reloc) return 0; } +/* Return -1 error, 0 success, 1 skip */ static int convert_reloc_secsym_to_sym(struct elf *elf, struct reloc *reloc) { struct symbol *sym = reloc->sym; struct section *sec = sym->sec; + if (!is_sec_sym(sym)) + return 0; + /* If the symbol has a dedicated section, it's easy to find */ sym = find_symbol_by_offset(sec, 0); if (sym && sym->len == sec_size(sec)) @@ -1027,22 +1002,34 @@ static int convert_reloc_secsym_to_sym(struct elf *elf, struct reloc *reloc) return 0; } +/* + * Sections with anonymous or uncorrelated data (strings, UBSAN data) + * need section symbol references. + */ +static bool is_uncorrelated_section(struct section *sec) +{ + return is_string_sec(sec) || + strstarts(sec->name, ".rodata") || + strstarts(sec->name, ".data..Lubsan") || /* GCC */ + strstarts(sec->name, ".data..L__unnamed_"); /* Clang */ +} + /* * Convert a relocation symbol reference to the needed format: either a section - * symbol or the underlying symbol itself. + * symbol or the underlying symbol itself. Return -1 error, 0 success, 1 skip. */ static int convert_reloc_sym(struct elf *elf, struct reloc *reloc) { + struct section *sec = reloc->sym->sec; + if (reloc_type(reloc) == R_NONE) return 1; - if (is_reloc_allowed(reloc)) - return 0; - - if (section_reference_needed(reloc->sym->sec)) + if (is_uncorrelated_section(sec)) return convert_reloc_sym_to_secsym(elf, reloc); - else - return convert_reloc_secsym_to_sym(elf, reloc); + + /* Everything else: references should use named symbols. */ + return convert_reloc_secsym_to_sym(elf, reloc); } /* @@ -1187,13 +1174,6 @@ static int clone_reloc(struct elfs *e, struct reloc *patched_reloc, struct symbol *out_sym; bool klp; - if (!is_reloc_allowed(patched_reloc)) { - ERROR_FUNC(patched_reloc->sec->base, reloc_offset(patched_reloc), - "missing symbol for reference to %s+%ld", - patched_sym->name, addend); - return -1; - } - klp = klp_reloc_needed(patched_reloc); dbg_clone_reloc(sec, offset, patched_sym, addend, export, klp); @@ -1223,7 +1203,7 @@ static int clone_reloc(struct elfs *e, struct reloc *patched_reloc, /* * For strings, all references use section symbols, thanks to - * section_reference_needed(). clone_symbol() has cloned an empty + * convert_reloc_sym(). clone_symbol() has cloned an empty * version of the string section. Now copy the string itself. */ if (is_string_sec(patched_sym->sec)) { -- 2.53.0
