diff options
| -rw-r--r-- | arch/Kconfig | 4 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/jump_label.h | 6 | ||||
| -rw-r--r-- | scripts/Makefile.build | 1 | ||||
| -rwxr-xr-x | scripts/link-vmlinux.sh | 4 | ||||
| -rw-r--r-- | tools/objtool/builtin-check.c | 37 | ||||
| -rw-r--r-- | tools/objtool/check.c | 2 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/builtin.h | 1 |
8 files changed, 44 insertions, 12 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 04cdef16db24..9dce6d6e3bc3 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -46,6 +46,7 @@ config JUMP_LABEL bool "Optimize very unlikely/likely branches" depends on HAVE_ARCH_JUMP_LABEL depends on CC_HAS_ASM_GOTO + select OBJTOOL if HAVE_JUMP_LABEL_HACK help This option enables a transparent branch optimization that makes certain almost-always-true or almost-always-false branch @@ -1031,6 +1032,9 @@ config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT config HAVE_OBJTOOL bool +config HAVE_JUMP_LABEL_HACK + bool + config HAVE_STACK_VALIDATION bool help diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 43e26ee1611e..26d012f1eeb8 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -212,6 +212,7 @@ config X86 select HAVE_IOREMAP_PROT select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 select HAVE_IRQ_TIME_ACCOUNTING + select HAVE_JUMP_LABEL_HACK if HAVE_OBJTOOL select HAVE_KERNEL_BZIP2 select HAVE_KERNEL_GZIP select HAVE_KERNEL_LZ4 diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h index 3ce0e67c579c..071572e23d3a 100644 --- a/arch/x86/include/asm/jump_label.h +++ b/arch/x86/include/asm/jump_label.h @@ -20,7 +20,7 @@ _ASM_PTR "%c0 + %c1 - .\n\t" \ ".popsection \n\t" -#ifdef CONFIG_OBJTOOL +#ifdef CONFIG_HAVE_JUMP_LABEL_HACK static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { @@ -34,7 +34,7 @@ l_yes: return true; } -#else /* !CONFIG_OBJTOOL */ +#else /* !CONFIG_HAVE_JUMP_LABEL_HACK */ static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) { @@ -48,7 +48,7 @@ l_yes: return true; } -#endif /* CONFIG_OBJTOOL */ +#endif /* CONFIG_HAVE_JUMP_LABEL_HACK */ static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) { diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 3f20d565733c..f1d2c2e4f15b 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -227,6 +227,7 @@ ifdef CONFIG_OBJTOOL objtool := $(objtree)/tools/objtool/objtool objtool_args = \ + $(if $(CONFIG_HAVE_JUMP_LABEL_HACK), --hacks=jump_label) \ $(if $(CONFIG_X86_KERNEL_IBT), --lto --ibt) \ $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) \ $(if $(CONFIG_UNWINDER_ORC), --orc) \ diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 33f14fe1ddde..fa1f16840e76 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -117,6 +117,10 @@ objtool_link() # Don't perform vmlinux validation unless explicitly requested, # but run objtool on vmlinux.o now that we have an object file. + if is_enabled CONFIG_HAVE_JUMP_LABEL_HACK; then + objtoolopt="${objtoolopt} --hacks=jump_label" + fi + if is_enabled CONFIG_X86_KERNEL_IBT; then objtoolopt="${objtoolopt} --ibt" fi diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index c8c4d2bab42f..b2c626d9e2bf 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -31,8 +31,28 @@ static int parse_dump(const struct option *opt, const char *str, int unset) return -1; } +static int parse_hacks(const struct option *opt, const char *str, int unset) +{ + bool found = false; + + /* + * Use strstr() as a lazy method of checking for comma-separated + * options. + * + * No string provided == enable all options. + */ + + if (!str || strstr(str, "jump_label")) { + opts.hack_jump_label = true; + found = true; + } + + return found ? 0 : -1; +} + const struct option check_options[] = { OPT_GROUP("Actions:"), + OPT_CALLBACK_OPTARG('h', "hacks", NULL, NULL, "jump_label", "patch toolchain bugs/limitations", parse_hacks), OPT_BOOLEAN('i', "ibt", &opts.ibt, "validate and annotate IBT"), OPT_BOOLEAN('m', "mcount", &opts.mcount, "annotate mcount/fentry calls for ftrace"), OPT_BOOLEAN('n', "noinstr", &opts.noinstr, "validate noinstr rules"), @@ -87,14 +107,15 @@ int cmd_parse_options(int argc, const char **argv, const char * const usage[]) static bool opts_valid(void) { - if (opts.ibt || - opts.mcount || - opts.noinstr || - opts.orc || - opts.retpoline || - opts.sls || - opts.stackval || - opts.static_call || + if (opts.hack_jump_label || + opts.ibt || + opts.mcount || + opts.noinstr || + opts.orc || + opts.retpoline || + opts.sls || + opts.stackval || + opts.static_call || opts.uaccess) { if (opts.dump_orc) { fprintf(stderr, "--dump can't be combined with other options\n"); diff --git a/tools/objtool/check.c b/tools/objtool/check.c index b9ac351ea08b..d157978c58b3 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1592,7 +1592,7 @@ static int handle_jump_alt(struct objtool_file *file, return -1; } - if (special_alt->key_addend & 2) { + if (opts.hack_jump_label && special_alt->key_addend & 2) { struct reloc *reloc = insn_reloc(file, orig_insn); if (reloc) { diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index dc4757205b8d..c6acf05ec859 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -12,6 +12,7 @@ extern const struct option check_options[]; struct opts { /* actions: */ bool dump_orc; + bool hack_jump_label; bool ibt; bool mcount; bool noinstr; |