diff options
| -rw-r--r-- | Makefile | 10 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 3 | ||||
| -rw-r--r-- | arch/x86/Makefile | 5 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/Makefile | 3 | ||||
| -rw-r--r-- | arch/x86/power/Makefile | 4 | ||||
| -rw-r--r-- | kernel/trace/Kconfig | 13 | ||||
| -rw-r--r-- | scripts/Makefile.build | 19 | ||||
| -rw-r--r-- | scripts/Makefile.lib | 12 | ||||
| -rw-r--r-- | scripts/Makefile.modfinal | 19 | ||||
| -rwxr-xr-x | scripts/link-vmlinux.sh | 28 | ||||
| -rw-r--r-- | tools/objtool/builtin-check.c | 10 | ||||
| -rw-r--r-- | tools/objtool/check.c | 97 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/builtin.h | 2 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/check.h | 1 | ||||
| -rw-r--r-- | tools/objtool/include/objtool/objtool.h | 1 | ||||
| -rw-r--r-- | tools/objtool/objtool.c | 1 |
16 files changed, 195 insertions, 33 deletions
@@ -862,6 +862,9 @@ ifdef CONFIG_FTRACE_MCOUNT_USE_CC endif endif endif +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + CC_FLAGS_USING += -DCC_USING_NOP_MCOUNT +endif ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_HAVE_C_RECORDMCOUNT BUILD_C_RECORDMCOUNT := y @@ -909,7 +912,8 @@ KBUILD_LDFLAGS += -mllvm -import-instr-limit=5 endif ifdef CONFIG_LTO -KBUILD_CFLAGS += $(CC_FLAGS_LTO) +KBUILD_CFLAGS += -fno-lto $(CC_FLAGS_LTO) +KBUILD_AFLAGS += -fno-lto export CC_FLAGS_LTO endif @@ -1243,6 +1247,10 @@ uapi-asm-generic: PHONY += prepare-objtool prepare-resolve_btfids prepare-objtool: $(objtool_target) ifeq ($(SKIP_STACK_VALIDATION),1) +ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL + @echo "error: Cannot generate __mcount_loc for CONFIG_DYNAMIC_FTRACE=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 + @false +endif ifdef CONFIG_UNWINDER_ORC @echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2 @false diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 595193bc2d31..792517c078c5 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -97,6 +97,8 @@ config X86 select ARCH_SUPPORTS_DEBUG_PAGEALLOC select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096 + select ARCH_SUPPORTS_LTO_CLANG if X86_64 + select ARCH_SUPPORTS_LTO_CLANG_THIN if X86_64 select ARCH_USE_BUILTIN_BSWAP select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS @@ -169,6 +171,7 @@ config X86 select HAVE_CONTEXT_TRACKING if X86_64 select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING select HAVE_C_RECORDMCOUNT + select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE diff --git a/arch/x86/Makefile b/arch/x86/Makefile index b797f1561943..2d6d5a28c3bf 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -169,6 +169,11 @@ ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1) KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,) endif +ifdef CONFIG_LTO_CLANG +KBUILD_LDFLAGS += -plugin-opt=-code-model=kernel \ + -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8) +endif + # Workaround for a gcc prelease that unfortunately was shipped in a suse release KBUILD_CFLAGS += -Wno-sign-compare # diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 02e3e42f380b..05c4abc2fdfd 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -91,7 +91,7 @@ ifneq ($(RETPOLINE_VDSO_CFLAGS),) endif endif -$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +$(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. @@ -150,6 +150,7 @@ KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic KBUILD_CFLAGS_32 += -fno-stack-protector KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls) diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile index 3ff80156f21a..379777572bc9 100644 --- a/arch/x86/power/Makefile +++ b/arch/x86/power/Makefile @@ -4,5 +4,9 @@ # itself be stack-protected CFLAGS_cpu.o := -fno-stack-protector +# Clang may incorrectly inline functions with stack protector enabled into +# __restore_processor_state(): https://bugs.llvm.org/show_bug.cgi?id=47479 +CFLAGS_REMOVE_cpu.o := $(CC_FLAGS_LTO) + obj-$(CONFIG_PM_SLEEP) += cpu.o obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 61cefb157b59..9c266b93cbc0 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -60,6 +60,11 @@ config HAVE_NOP_MCOUNT help Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount +config HAVE_OBJTOOL_MCOUNT + bool + help + Arch supports objtool --mcount + config HAVE_C_RECORDMCOUNT bool help @@ -612,10 +617,18 @@ config FTRACE_MCOUNT_USE_CC depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on FTRACE_MCOUNT_RECORD +config FTRACE_MCOUNT_USE_OBJTOOL + def_bool y + depends on HAVE_OBJTOOL_MCOUNT + depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY + depends on !FTRACE_MCOUNT_USE_CC + depends on FTRACE_MCOUNT_RECORD + config FTRACE_MCOUNT_USE_RECORDMCOUNT def_bool y depends on !FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY depends on !FTRACE_MCOUNT_USE_CC + depends on !FTRACE_MCOUNT_USE_OBJTOOL depends on FTRACE_MCOUNT_RECORD config TRACING_MAP diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d94fc9ab819d..3f6bf0ea7c0e 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -218,27 +218,11 @@ cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT ifdef CONFIG_STACK_VALIDATION +ifndef CONFIG_LTO_CLANG ifneq ($(SKIP_STACK_VALIDATION),1) __objtool_obj := $(objtree)/tools/objtool/objtool -objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check) - -objtool_args += $(if $(part-of-module), --module,) - -ifndef CONFIG_FRAME_POINTER -objtool_args += --no-fp -endif -ifdef CONFIG_GCOV_KERNEL -objtool_args += --no-unreachable -endif -ifdef CONFIG_RETPOLINE - objtool_args += --retpoline -endif -ifdef CONFIG_X86_SMAP - objtool_args += --uaccess -endif - # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file @@ -250,6 +234,7 @@ objtool_obj = $(if $(patsubst y%,, \ $(__objtool_obj)) endif # SKIP_STACK_VALIDATION +endif # CONFIG_LTO_CLANG endif # CONFIG_STACK_VALIDATION # Rebuild all objects when objtool changes, or is enabled/disabled. diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 2301babd3fbc..9f2531567c0e 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -222,6 +222,18 @@ dtc_cpp_flags = -Wp,-MMD,$(depfile).pre.tmp -nostdinc \ $(addprefix -I,$(DTC_INCLUDE)) \ -undef -D__DTS__ +# Objtool arguments are also needed for modfinal with LTO, so we define +# then here to avoid duplication. +objtool_args = \ + $(if $(CONFIG_UNWINDER_ORC),orc generate,check) \ + $(if $(part-of-module), --module,) \ + $(if $(CONFIG_FRAME_POINTER),, --no-fp) \ + $(if $(or $(CONFIG_GCOV_KERNEL),$(CONFIG_LTO_CLANG)), \ + --no-unreachable,) \ + $(if $(CONFIG_RETPOLINE), --retpoline,) \ + $(if $(CONFIG_X86_SMAP), --uaccess,) \ + $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount,) + # Useful for describing the dependency of composite objects # Usage: # $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 6de2c35b64e8..735e11e9041b 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -9,7 +9,7 @@ __modfinal: include include/config/auto.conf include $(srctree)/scripts/Kbuild.include -# for c_flags +# for c_flags and objtool_args include $(srctree)/scripts/Makefile.lib # find all modules listed in modules.order @@ -34,10 +34,23 @@ ifdef CONFIG_LTO_CLANG # With CONFIG_LTO_CLANG, reuse the object file we compiled for modpost to # avoid a second slow LTO link prelink-ext := .lto -endif + +# ELF processing was skipped earlier because we didn't have native code, +# so let's now process the prelinked binary before we link the module. + +ifdef CONFIG_STACK_VALIDATION +ifneq ($(SKIP_STACK_VALIDATION),1) +cmd_ld_ko_o += \ + $(objtree)/tools/objtool/objtool $(objtool_args) \ + $(@:.ko=$(prelink-ext).o); + +endif # SKIP_STACK_VALIDATION +endif # CONFIG_STACK_VALIDATION + +endif # CONFIG_LTO_CLANG quiet_cmd_ld_ko_o = LD [M] $@ - cmd_ld_ko_o = \ + cmd_ld_ko_o += \ $(LD) -r $(KBUILD_LDFLAGS) \ $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ -T scripts/module.lds -o $@ $(filter %.o, $^); \ diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index c5919d5a0b4f..3b261b0f74f0 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -103,14 +103,36 @@ modpost_link() objtool_link() { + local objtoolcmd; local objtoolopt; + if [ "${CONFIG_LTO_CLANG} ${CONFIG_STACK_VALIDATION}" = "y y" ]; then + # Don't perform vmlinux validation unless explicitly requested, + # but run objtool on vmlinux.o now that we have an object file. + if [ -n "${CONFIG_UNWINDER_ORC}" ]; then + objtoolcmd="orc generate" + fi + + objtoolopt="${objtoolopt} --duplicate" + + if [ -n "${CONFIG_FTRACE_MCOUNT_USE_OBJTOOL}" ]; then + objtoolopt="${objtoolopt} --mcount" + fi + fi + if [ -n "${CONFIG_VMLINUX_VALIDATION}" ]; then - objtoolopt="check" + objtoolopt="${objtoolopt} --noinstr" + fi + + if [ -n "${objtoolopt}" ]; then + if [ -z "${objtoolcmd}" ]; then + objtoolcmd="check" + fi + objtoolopt="${objtoolopt} --vmlinux" if [ -z "${CONFIG_FRAME_POINTER}" ]; then objtoolopt="${objtoolopt} --no-fp" fi - if [ -n "${CONFIG_GCOV_KERNEL}" ]; then + if [ -n "${CONFIG_GCOV_KERNEL}" ] || [ -n "${CONFIG_LTO_CLANG}" ]; then objtoolopt="${objtoolopt} --no-unreachable" fi if [ -n "${CONFIG_RETPOLINE}" ]; then @@ -120,7 +142,7 @@ objtool_link() objtoolopt="${objtoolopt} --uaccess" fi info OBJTOOL ${1} - tools/objtool/objtool ${objtoolopt} ${1} + tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1} fi } diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index f47951e19c9d..c3a85d8f6c5c 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -18,7 +18,7 @@ #include <objtool/builtin.h> #include <objtool/objtool.h> -bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; +bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr; static const char * const check_usage[] = { "objtool check [<options>] file.o", @@ -34,13 +34,15 @@ const struct option check_options[] = { OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"), OPT_BOOLEAN('s', "stats", &stats, "print statistics"), OPT_BOOLEAN('d', "duplicate", &validate_dup, "duplicate validation for vmlinux.o"), + OPT_BOOLEAN('n', "noinstr", &noinstr, "noinstr validation for vmlinux.o"), OPT_BOOLEAN('l', "vmlinux", &vmlinux, "vmlinux.o validation"), + OPT_BOOLEAN('M', "mcount", &mcount, "generate __mcount_loc"), OPT_END(), }; int cmd_check(int argc, const char **argv) { - const char *objname, *s; + const char *objname; struct objtool_file *file; int ret; @@ -51,10 +53,6 @@ int cmd_check(int argc, const char **argv) objname = argv[0]; - s = strstr(objname, "vmlinux.o"); - if (s && !s[9]) - vmlinux = true; - file = objtool_open_read(objname); if (!file) return 1; diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 331a763d8775..080a3d6cbd75 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -249,7 +249,7 @@ static void init_insn_state(struct insn_state *state, struct section *sec) * not correctly determine insn->call_dest->sec (external symbols do * not have a section). */ - if (vmlinux && sec) + if (vmlinux && noinstr && sec) state->noinstr = sec->noinstr; } @@ -548,6 +548,78 @@ static int create_static_call_sections(struct objtool_file *file) return 0; } +static int create_mcount_loc_sections(struct objtool_file *file) +{ + struct section *sec, *reloc_sec; + struct reloc *reloc; + unsigned long *loc; + struct instruction *insn; + int idx; + + sec = find_section_by_name(file->elf, "__mcount_loc"); + if (sec) { + INIT_LIST_HEAD(&file->mcount_loc_list); + WARN("file already has __mcount_loc section, skipping"); + return 0; + } + + if (list_empty(&file->mcount_loc_list)) + return 0; + + idx = 0; + list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node) + idx++; + + sec = elf_create_section(file->elf, "__mcount_loc", 0, sizeof(unsigned long), idx); + if (!sec) + return -1; + + reloc_sec = elf_create_reloc_section(file->elf, sec, SHT_RELA); + if (!reloc_sec) + return -1; + + idx = 0; + list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node) { + + loc = (unsigned long *)sec->data->d_buf + idx; + memset(loc, 0, sizeof(unsigned long)); + + reloc = malloc(sizeof(*reloc)); + if (!reloc) { + perror("malloc"); + return -1; + } + memset(reloc, 0, sizeof(*reloc)); + + if (insn->sec->sym) { + reloc->sym = insn->sec->sym; + reloc->addend = insn->offset; + } else { + reloc->sym = find_symbol_containing(insn->sec, insn->offset); + + if (!reloc->sym) { + WARN("missing symbol for insn at offset 0x%lx\n", + insn->offset); + return -1; + } + + reloc->addend = insn->offset - reloc->sym->offset; + } + + reloc->type = R_X86_64_64; + reloc->offset = idx * sizeof(unsigned long); + reloc->sec = reloc_sec; + elf_add_reloc(file->elf, reloc); + + idx++; + } + + if (elf_rebuild_reloc_section(file->elf, reloc_sec)) + return -1; + + return 0; +} + /* * Warnings shouldn't be reported for ignored functions. */ @@ -975,6 +1047,22 @@ static int add_call_destinations(struct objtool_file *file) insn->type = INSN_NOP; } + if (mcount && !strcmp(insn->call_dest->name, "__fentry__")) { + if (reloc) { + reloc->type = R_NONE; + elf_write_reloc(file->elf, reloc); + } + + elf_write_insn(file->elf, insn->sec, + insn->offset, insn->len, + arch_nop_insn(insn->len)); + + insn->type = INSN_NOP; + + list_add_tail(&insn->mcount_loc_node, + &file->mcount_loc_list); + } + /* * Whatever stack impact regular CALLs have, should be undone * by the RETURN of the called function. @@ -3048,6 +3136,13 @@ int check(struct objtool_file *file) goto out; warnings += ret; + if (mcount) { + ret = create_mcount_loc_sections(file); + if (ret < 0) + goto out; + warnings += ret; + } + out: /* * For now, don't fail the kernel build on fatal warnings. These diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 85c979caa367..2502bb27de17 100644 --- a/tools/objtool/include/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h @@ -8,7 +8,7 @@ #include <subcmd/parse-options.h> extern const struct option check_options[]; -extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; +extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux, mcount, noinstr; extern int cmd_check(int argc, const char **argv); extern int cmd_orc(int argc, const char **argv); diff --git a/tools/objtool/include/objtool/check.h b/tools/objtool/include/objtool/check.h index 4891ead0e85f..f5be798107bc 100644 --- a/tools/objtool/include/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -40,6 +40,7 @@ struct instruction { struct list_head list; struct hlist_node hash; struct list_head static_call_node; + struct list_head mcount_loc_node; struct section *sec; unsigned long offset; unsigned int len; diff --git a/tools/objtool/include/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h index e114642efb65..e68e37476c15 100644 --- a/tools/objtool/include/objtool/objtool.h +++ b/tools/objtool/include/objtool/objtool.h @@ -19,6 +19,7 @@ struct objtool_file { struct list_head insn_list; DECLARE_HASHTABLE(insn_hash, 20); struct list_head static_call_list; + struct list_head mcount_loc_list; bool ignore_unreachables, c_file, hints, rodata; }; diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c index e848feb0a5fc..7b97ce499405 100644 --- a/tools/objtool/objtool.c +++ b/tools/objtool/objtool.c @@ -62,6 +62,7 @@ struct objtool_file *objtool_open_read(const char *_objname) INIT_LIST_HEAD(&file.insn_list); hash_init(file.insn_hash); INIT_LIST_HEAD(&file.static_call_list); + INIT_LIST_HEAD(&file.mcount_loc_list); file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment"); file.ignore_unreachables = no_unreachable; file.hints = false; |