Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> --- include/linux/objtool.h | 16 ++---- include/linux/objtool_types.h | 1 tools/include/linux/objtool_types.h | 1 tools/objtool/check.c | 96 ++++++++++++++---------------------- 4 files changed, 47 insertions(+), 67 deletions(-) --- a/include/linux/objtool.h +++ b/include/linux/objtool.h @@ -66,16 +66,6 @@ #else /* __ASSEMBLY__ */ /* - * This macro indicates that the following intra-function call is valid. - * Any non-annotated intra-function call will cause objtool to issue a warning. - */ -#define ANNOTATE_INTRA_FUNCTION_CALL \ - 999: \ - .pushsection .discard.intra_function_calls; \ - .long 999b; \ - .popsection; - -/* * In asm, there are two kinds of code: normal C-type callable functions and * the rest. The normal callable functions can be called by other code, and * don't do anything unusual with the stack. Such normal callable functions @@ -152,6 +142,12 @@ #define ANNOTATE_NOENDBR ANNOTATE type=ANNOTYPE_NOENDBR +/* + * This macro indicates that the following intra-function call is valid. + * Any non-annotated intra-function call will cause objtool to issue a warning. + */ +#define ANNOTATE_INTRA_FUNCTION_CALL ANNOTATE type=ANNOTYPE_INTRA_FUNCTION_CALLS + #endif /* __ASSEMBLY__ */ #else /* !CONFIG_OBJTOOL */ --- a/include/linux/objtool_types.h +++ b/include/linux/objtool_types.h @@ -63,5 +63,6 @@ struct unwind_hint { #define ANNOTYPE_INSTR_END 4 #define ANNOTYPE_UNRET_BEGIN 5 #define ANNOTYPE_IGNORE_ALTS 6 +#define ANNOTYPE_INTRA_FUNCTION_CALLS 7 #endif /* _LINUX_OBJTOOL_TYPES_H */ --- a/tools/include/linux/objtool_types.h +++ b/tools/include/linux/objtool_types.h @@ -63,5 +63,6 @@ struct unwind_hint { #define ANNOTYPE_INSTR_END 4 #define ANNOTYPE_UNRET_BEGIN 5 #define ANNOTYPE_IGNORE_ALTS 6 +#define ANNOTYPE_INTRA_FUNCTION_CALLS 7 #endif /* _LINUX_OBJTOOL_TYPES_H */ --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2274,7 +2274,8 @@ static int read_unwind_hints(struct objt return 0; } -static int read_annotate(struct objtool_file *file, int (*func)(int type, struct instruction *insn)) +static int read_annotate(struct objtool_file *file, + int (*func)(struct objtool_file *file, int type, struct instruction *insn)) { struct section *rsec, *sec; struct instruction *insn; @@ -2299,7 +2300,7 @@ static int read_annotate(struct objtool_ type = *(u32 *)(sec->data->d_buf + (reloc_idx(reloc) * sec->sh.sh_entsize) + 4); - ret = func(type, insn); + ret = func(file, type, insn); if (ret < 0) return ret; } @@ -2307,7 +2308,7 @@ static int read_annotate(struct objtool_ return 0; } -static int __annotate_ignore_alts(int type, struct instruction *insn) +static int __annotate_ignore_alts(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_IGNORE_ALTS) return 0; @@ -2316,7 +2317,7 @@ static int __annotate_ignore_alts(int ty return 0; } -static int __annotate_noendbr(int type, struct instruction *insn) +static int __annotate_noendbr(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_NOENDBR) return 0; @@ -2325,7 +2326,37 @@ static int __annotate_noendbr(int type, return 0; } -static int __annotate_retpoline_safe(int type, struct instruction *insn) +static int __annotate_ifc(struct objtool_file *file, int type, struct instruction *insn) +{ + unsigned long dest_off; + + if (type != ANNOTYPE_INTRA_FUNCTION_CALLS) + return 0; + + if (insn->type != INSN_CALL) { + WARN_INSN(insn, "intra_function_call not a direct call"); + return -1; + } + + /* + * Treat intra-function CALLs as JMPs, but with a stack_op. + * See add_call_destinations(), which strips stack_ops from + * normal CALLs. + */ + insn->type = INSN_JUMP_UNCONDITIONAL; + + dest_off = arch_jump_destination(insn); + insn->jump_dest = find_insn(file, insn->sec, dest_off); + if (!insn->jump_dest) { + WARN_INSN(insn, "can't find call dest at %s+0x%lx", + insn->sec->name, dest_off); + return -1; + } + + return 0; +} + +static int __annotate_retpoline_safe(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_RETPOLINE_SAFE) return 0; @@ -2342,7 +2373,7 @@ static int __annotate_retpoline_safe(int return 0; } -static int __annotate_instr(int type, struct instruction *insn) +static int __annotate_instr(struct objtool_file *file, int type, struct instruction *insn) { switch (type) { case ANNOTYPE_INSTR_BEGIN: @@ -2360,7 +2391,7 @@ static int __annotate_instr(int type, st return 0; } -static int __annotate_unret(int type, struct instruction *insn) +static int __annotate_unret(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_UNRET_BEGIN) return 0; @@ -2370,55 +2401,6 @@ static int __annotate_unret(int type, st } -static int read_intra_function_calls(struct objtool_file *file) -{ - struct instruction *insn; - struct section *rsec; - struct reloc *reloc; - - rsec = find_section_by_name(file->elf, ".rela.discard.intra_function_calls"); - if (!rsec) - return 0; - - for_each_reloc(rsec, reloc) { - unsigned long dest_off; - - if (reloc->sym->type != STT_SECTION) { - WARN("unexpected relocation symbol type in %s", - rsec->name); - return -1; - } - - insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc)); - if (!insn) { - WARN("bad .discard.intra_function_call entry"); - return -1; - } - - if (insn->type != INSN_CALL) { - WARN_INSN(insn, "intra_function_call not a direct call"); - return -1; - } - - /* - * Treat intra-function CALLs as JMPs, but with a stack_op. - * See add_call_destinations(), which strips stack_ops from - * normal CALLs. - */ - insn->type = INSN_JUMP_UNCONDITIONAL; - - dest_off = arch_jump_destination(insn); - insn->jump_dest = find_insn(file, insn->sec, dest_off); - if (!insn->jump_dest) { - WARN_INSN(insn, "can't find call dest at %s+0x%lx", - insn->sec->name, dest_off); - return -1; - } - } - - return 0; -} - /* * Return true if name matches an instrumentation function, where calls to that * function from noinstr code can safely be removed, but compilers won't do so. @@ -2554,7 +2536,7 @@ static int decode_sections(struct objtoo * Must be before add_call_destination(); it changes INSN_CALL to * INSN_JUMP. */ - ret = read_intra_function_calls(file); + ret = read_annotate(file, __annotate_ifc); if (ret) return ret;