From 89bc853eae4ad125030ef99f207ba76c2f00a26e Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Tue, 8 Mar 2022 16:30:55 +0100
Subject: objtool: Find unused ENDBR instructions

Find all ENDBR instructions which are never referenced and stick them
in a section such that the kernel can poison them, sealing the
functions from ever being an indirect call target.

This removes about 1-in-4 ENDBR instructions.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154319.763643193@infradead.org
---
 tools/objtool/objtool.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'tools/objtool/objtool.c')

diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index bdf699f6552b..b09946f4e1d6 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -128,6 +128,7 @@ struct objtool_file *objtool_open_read(const char *_objname)
 	INIT_LIST_HEAD(&file.retpoline_call_list);
 	INIT_LIST_HEAD(&file.static_call_list);
 	INIT_LIST_HEAD(&file.mcount_loc_list);
+	INIT_LIST_HEAD(&file.endbr_list);
 	file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment");
 	file.ignore_unreachables = no_unreachable;
 	file.hints = false;
-- 
cgit 


From 08feafe8d1958febf3a9733a3d1564d8fc23340e Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Mon, 11 Apr 2022 16:10:32 -0700
Subject: objtool: Fix function fallthrough detection for vmlinux

Objtool's function fallthrough detection only works on C objects.
The distinction between C and assembly objects no longer makes sense
with objtool running on vmlinux.o.

Now that copy_user_64.S has been fixed up, and an objtool sibling call
detection bug has been fixed, the asm code is in "compliance" and this
hack is no longer needed.  Remove it.

Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/b434cff98eca3a60dcc64c620d7d5d405a0f441c.1649718562.git.jpoimboe@redhat.com
---
 tools/objtool/check.c                   | 2 +-
 tools/objtool/include/objtool/objtool.h | 2 +-
 tools/objtool/objtool.c                 | 1 -
 3 files changed, 2 insertions(+), 3 deletions(-)

(limited to 'tools/objtool/objtool.c')

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 0f5d3de30e0d..5f10653eb5c2 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -3310,7 +3310,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 	while (1) {
 		next_insn = next_insn_to_validate(file, insn);
 
-		if (file->c_file && func && insn->func && func != insn->func->pfunc) {
+		if (func && insn->func && func != insn->func->pfunc) {
 			WARN("%s() falls through to next function %s()",
 			     func->name, insn->func->name);
 			return 1;
diff --git a/tools/objtool/include/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h
index 7a5c13a78f87..a6e72d916807 100644
--- a/tools/objtool/include/objtool/objtool.h
+++ b/tools/objtool/include/objtool/objtool.h
@@ -27,7 +27,7 @@ struct objtool_file {
 	struct list_head static_call_list;
 	struct list_head mcount_loc_list;
 	struct list_head endbr_list;
-	bool ignore_unreachables, c_file, hints, rodata;
+	bool ignore_unreachables, hints, rodata;
 
 	unsigned int nr_endbr;
 	unsigned int nr_endbr_int;
diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index b09946f4e1d6..843ff3c2f28e 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -129,7 +129,6 @@ struct objtool_file *objtool_open_read(const char *_objname)
 	INIT_LIST_HEAD(&file.static_call_list);
 	INIT_LIST_HEAD(&file.mcount_loc_list);
 	INIT_LIST_HEAD(&file.endbr_list);
-	file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment");
 	file.ignore_unreachables = no_unreachable;
 	file.hints = false;
 
-- 
cgit 


From 2daf7faba7ded8703e4b4ebc8b161f22272fc91a Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Mon, 18 Apr 2022 09:50:26 -0700
Subject: objtool: Reorganize cmdline options

Split the existing options into two groups: actions, which actually do
something; and options, which modify the actions in some way.

Also there's no need to have short flags for all the non-action options.
Reserve short flags for the more important actions.

While at it:

- change a few of the short flags to be more intuitive

- make option descriptions more consistently descriptive

- sort options in the source like they are when printed

- move options to a global struct

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/9dcaa752f83aca24b1b21f0b0eeb28a0c181c0b0.1650300597.git.jpoimboe@redhat.com
---
 scripts/Makefile.build                  | 10 +++---
 scripts/link-vmlinux.sh                 | 30 ++++++++++------
 tools/objtool/arch/x86/decode.c         |  2 +-
 tools/objtool/arch/x86/special.c        |  2 +-
 tools/objtool/builtin-check.c           | 40 +++++++++++----------
 tools/objtool/check.c                   | 62 ++++++++++++++++-----------------
 tools/objtool/elf.c                     |  8 ++---
 tools/objtool/include/objtool/builtin.h | 26 ++++++++++++--
 tools/objtool/objtool.c                 |  6 ++--
 9 files changed, 108 insertions(+), 78 deletions(-)

(limited to 'tools/objtool/objtool.c')

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 33c1ed581522..dd9d582808d6 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -228,14 +228,14 @@ objtool := $(objtree)/tools/objtool/objtool
 
 objtool_args =								\
 	$(if $(CONFIG_UNWINDER_ORC),orc generate,check)			\
-	$(if $(part-of-module), --module)				\
 	$(if $(CONFIG_X86_KERNEL_IBT), --lto --ibt)			\
-	$(if $(CONFIG_FRAME_POINTER),, --no-fp)				\
-	$(if $(CONFIG_GCOV_KERNEL), --no-unreachable)			\
+	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
 	$(if $(CONFIG_RETPOLINE), --retpoline)				\
+	$(if $(CONFIG_SLS), --sls)					\
 	$(if $(CONFIG_X86_SMAP), --uaccess)				\
-	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
-	$(if $(CONFIG_SLS), --sls)
+	$(if $(part-of-module), --module)				\
+	$(if $(CONFIG_FRAME_POINTER),, --no-fp)				\
+	$(if $(CONFIG_GCOV_KERNEL), --no-unreachable)
 
 cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@)
 cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index 9361a1ef02c9..c6e9fef61b11 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -117,8 +117,6 @@ objtool_link()
 			objtoolcmd="orc generate"
 		fi
 
-		objtoolopt="${objtoolopt} --lto"
-
 		if is_enabled CONFIG_X86_KERNEL_IBT; then
 			objtoolopt="${objtoolopt} --ibt"
 		fi
@@ -126,6 +124,8 @@ objtool_link()
 		if is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL; then
 			objtoolopt="${objtoolopt} --mcount"
 		fi
+
+		objtoolopt="${objtoolopt} --lto"
 	fi
 
 	if is_enabled CONFIG_VMLINUX_VALIDATION; then
@@ -133,25 +133,33 @@ objtool_link()
 	fi
 
 	if [ -n "${objtoolopt}" ]; then
+
 		if [ -z "${objtoolcmd}" ]; then
 			objtoolcmd="check"
 		fi
-		objtoolopt="${objtoolopt} --vmlinux"
-		if ! is_enabled CONFIG_FRAME_POINTER; then
-			objtoolopt="${objtoolopt} --no-fp"
-		fi
-		if is_enabled CONFIG_GCOV_KERNEL; then
-			objtoolopt="${objtoolopt} --no-unreachable"
-		fi
+
 		if is_enabled CONFIG_RETPOLINE; then
 			objtoolopt="${objtoolopt} --retpoline"
 		fi
+
+		if is_enabled CONFIG_SLS; then
+			objtoolopt="${objtoolopt} --sls"
+		fi
+
 		if is_enabled CONFIG_X86_SMAP; then
 			objtoolopt="${objtoolopt} --uaccess"
 		fi
-		if is_enabled CONFIG_SLS; then
-			objtoolopt="${objtoolopt} --sls"
+
+		if ! is_enabled CONFIG_FRAME_POINTER; then
+			objtoolopt="${objtoolopt} --no-fp"
 		fi
+
+		if is_enabled CONFIG_GCOV_KERNEL; then
+			objtoolopt="${objtoolopt} --no-unreachable"
+		fi
+
+		objtoolopt="${objtoolopt} --vmlinux"
+
 		info OBJTOOL ${1}
 		tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1}
 	fi
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 943cb41cddf7..8b990a52aada 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -581,7 +581,7 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
 		break;
 
 	case 0xc7: /* mov imm, r/m */
-		if (!noinstr)
+		if (!opts.noinstr)
 			break;
 
 		if (insn.length == 3+4+4 && !strncmp(sec->name, ".init.text", 10)) {
diff --git a/tools/objtool/arch/x86/special.c b/tools/objtool/arch/x86/special.c
index e707d9bcd161..7c97b7391279 100644
--- a/tools/objtool/arch/x86/special.c
+++ b/tools/objtool/arch/x86/special.c
@@ -20,7 +20,7 @@ void arch_handle_alternative(unsigned short feature, struct special_alt *alt)
 		 * find paths that see the STAC but take the NOP instead of
 		 * CLAC and the other way around.
 		 */
-		if (uaccess)
+		if (opts.uaccess)
 			alt->skip_orig = true;
 		else
 			alt->skip_alt = true;
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index fc6975ab8b06..bc447b3cd9f2 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -19,12 +19,10 @@
 #include <objtool/builtin.h>
 #include <objtool/objtool.h>
 
-bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats,
-     lto, vmlinux, mcount, noinstr, backup, sls, dryrun,
-     ibt;
+struct opts opts;
 
 static const char * const check_usage[] = {
-	"objtool check [<options>] file.o",
+	"objtool check <actions> [<options>] file.o",
 	NULL,
 };
 
@@ -34,21 +32,25 @@ static const char * const env_usage[] = {
 };
 
 const struct option check_options[] = {
-	OPT_BOOLEAN('f', "no-fp", &no_fp, "Skip frame pointer validation"),
-	OPT_BOOLEAN('u', "no-unreachable", &no_unreachable, "Skip 'unreachable instruction' warnings"),
-	OPT_BOOLEAN('r', "retpoline", &retpoline, "Validate retpoline assumptions"),
-	OPT_BOOLEAN('m', "module", &module, "Indicates the object will be part of a kernel module"),
-	OPT_BOOLEAN('b', "backtrace", &backtrace, "unwind on error"),
-	OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"),
-	OPT_BOOLEAN('s', "stats", &stats, "print statistics"),
-	OPT_BOOLEAN(0, "lto", &lto, "whole-archive like runs"),
-	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_BOOLEAN('B', "backup", &backup, "create .orig files before modification"),
-	OPT_BOOLEAN('S', "sls", &sls, "validate straight-line-speculation"),
-	OPT_BOOLEAN(0, "dry-run", &dryrun, "don't write the modifications"),
-	OPT_BOOLEAN(0, "ibt", &ibt, "validate ENDBR placement"),
+	OPT_GROUP("Actions:"),
+	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"),
+	OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"),
+	OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"),
+	OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"),
+
+	OPT_GROUP("Options:"),
+	OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"),
+	OPT_BOOLEAN(0, "backup", &opts.backup, "create .orig files before modification"),
+	OPT_BOOLEAN(0, "dry-run", &opts.dryrun, "don't write modifications"),
+	OPT_BOOLEAN(0, "lto", &opts.lto, "whole-archive like runs"),
+	OPT_BOOLEAN(0, "module", &opts.module, "object is part of a kernel module"),
+	OPT_BOOLEAN(0, "no-fp", &opts.no_fp, "skip frame pointer validation"),
+	OPT_BOOLEAN(0, "no-unreachable", &opts.no_unreachable, "skip 'unreachable instruction' warnings"),
+	OPT_BOOLEAN(0, "stats", &opts.stats, "print statistics"),
+	OPT_BOOLEAN(0, "vmlinux", &opts.vmlinux, "vmlinux.o validation"),
+
 	OPT_END(),
 };
 
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index ca5b74603008..3362cc3bdf1a 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -273,7 +273,7 @@ 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 && noinstr && sec)
+	if (opts.vmlinux && opts.noinstr && sec)
 		state->noinstr = sec->noinstr;
 }
 
@@ -339,7 +339,7 @@ static void *cfi_hash_alloc(unsigned long size)
 	if (cfi_hash == (void *)-1L) {
 		WARN("mmap fail cfi_hash");
 		cfi_hash = NULL;
-	}  else if (stats) {
+	}  else if (opts.stats) {
 		printf("cfi_bits: %d\n", cfi_bits);
 	}
 
@@ -434,7 +434,7 @@ static int decode_instructions(struct objtool_file *file)
 		}
 	}
 
-	if (stats)
+	if (opts.stats)
 		printf("nr_insns: %lu\n", nr_insns);
 
 	return 0;
@@ -497,7 +497,7 @@ static int init_pv_ops(struct objtool_file *file)
 	struct symbol *sym;
 	int idx, nr;
 
-	if (!noinstr)
+	if (!opts.noinstr)
 		return 0;
 
 	file->pv_ops = NULL;
@@ -668,7 +668,7 @@ static int create_static_call_sections(struct objtool_file *file)
 
 		key_sym = find_symbol_by_name(file->elf, tmp);
 		if (!key_sym) {
-			if (!module) {
+			if (!opts.module) {
 				WARN("static_call: can't find static_call_key symbol: %s", tmp);
 				return -1;
 			}
@@ -761,7 +761,7 @@ static int create_ibt_endbr_seal_sections(struct objtool_file *file)
 	list_for_each_entry(insn, &file->endbr_list, call_node)
 		idx++;
 
-	if (stats) {
+	if (opts.stats) {
 		printf("ibt: ENDBR at function start: %d\n", file->nr_endbr);
 		printf("ibt: ENDBR inside functions:  %d\n", file->nr_endbr_int);
 		printf("ibt: superfluous ENDBR:       %d\n", idx);
@@ -1028,7 +1028,7 @@ static void add_uaccess_safe(struct objtool_file *file)
 	struct symbol *func;
 	const char **name;
 
-	if (!uaccess)
+	if (!opts.uaccess)
 		return;
 
 	for (name = uaccess_safe_builtin; *name; name++) {
@@ -1170,7 +1170,7 @@ static void annotate_call_site(struct objtool_file *file,
 		return;
 	}
 
-	if (mcount && sym->fentry) {
+	if (opts.mcount && sym->fentry) {
 		if (sibling)
 			WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset);
 
@@ -1256,7 +1256,7 @@ static bool is_first_func_insn(struct objtool_file *file, struct instruction *in
 	if (insn->offset == insn->func->offset)
 		return true;
 
-	if (ibt) {
+	if (opts.ibt) {
 		struct instruction *prev = prev_insn_same_sym(file, insn);
 
 		if (prev && prev->type == INSN_ENDBR &&
@@ -1699,7 +1699,7 @@ static int add_special_section_alts(struct objtool_file *file)
 		free(special_alt);
 	}
 
-	if (stats) {
+	if (opts.stats) {
 		printf("jl\\\tNOP\tJMP\n");
 		printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);
 		printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);
@@ -1945,7 +1945,7 @@ static int read_unwind_hints(struct objtool_file *file)
 
 		insn->hint = true;
 
-		if (ibt && hint->type == UNWIND_HINT_TYPE_REGS_PARTIAL) {
+		if (opts.ibt && hint->type == UNWIND_HINT_TYPE_REGS_PARTIAL) {
 			struct symbol *sym = find_symbol_by_offset(insn->sec, insn->offset);
 
 			if (sym && sym->bind == STB_GLOBAL &&
@@ -2806,7 +2806,7 @@ static int update_cfi_state(struct instruction *insn,
 		}
 
 		/* detect when asm code uses rbp as a scratch register */
-		if (!no_fp && insn->func && op->src.reg == CFI_BP &&
+		if (!opts.no_fp && insn->func && op->src.reg == CFI_BP &&
 		    cfa->base != CFI_BP)
 			cfi->bp_scratch = true;
 		break;
@@ -3363,7 +3363,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 
 				ret = validate_branch(file, func, alt->insn, state);
 				if (ret) {
-					if (backtrace)
+					if (opts.backtrace)
 						BT_FUNC("(alt)", insn);
 					return ret;
 				}
@@ -3379,7 +3379,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 		switch (insn->type) {
 
 		case INSN_RETURN:
-			if (sls && !insn->retpoline_safe &&
+			if (opts.sls && !insn->retpoline_safe &&
 			    next_insn && next_insn->type != INSN_TRAP) {
 				WARN_FUNC("missing int3 after ret",
 					  insn->sec, insn->offset);
@@ -3392,7 +3392,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 			if (ret)
 				return ret;
 
-			if (!no_fp && func && !is_fentry_call(insn) &&
+			if (!opts.no_fp && func && !is_fentry_call(insn) &&
 			    !has_valid_stack_frame(&state)) {
 				WARN_FUNC("call without frame pointer save/setup",
 					  sec, insn->offset);
@@ -3415,7 +3415,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 				ret = validate_branch(file, func,
 						      insn->jump_dest, state);
 				if (ret) {
-					if (backtrace)
+					if (opts.backtrace)
 						BT_FUNC("(branch)", insn);
 					return ret;
 				}
@@ -3427,7 +3427,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 			break;
 
 		case INSN_JUMP_DYNAMIC:
-			if (sls && !insn->retpoline_safe &&
+			if (opts.sls && !insn->retpoline_safe &&
 			    next_insn && next_insn->type != INSN_TRAP) {
 				WARN_FUNC("missing int3 after indirect jump",
 					  insn->sec, insn->offset);
@@ -3499,7 +3499,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
 			break;
 		}
 
-		if (ibt)
+		if (opts.ibt)
 			validate_ibt_insn(file, insn);
 
 		if (insn->dead_end)
@@ -3541,7 +3541,7 @@ static int validate_unwind_hints(struct objtool_file *file, struct section *sec)
 	while (&insn->list != &file->insn_list && (!sec || insn->sec == sec)) {
 		if (insn->hint && !insn->visited && !insn->ignore) {
 			ret = validate_branch(file, insn->func, insn, state);
-			if (ret && backtrace)
+			if (ret && opts.backtrace)
 				BT_FUNC("<=== (hint)", insn);
 			warnings += ret;
 		}
@@ -3571,7 +3571,7 @@ static int validate_retpoline(struct objtool_file *file)
 		 * loaded late, they very much do need retpoline in their
 		 * .init.text
 		 */
-		if (!strcmp(insn->sec->name, ".init.text") && !module)
+		if (!strcmp(insn->sec->name, ".init.text") && !opts.module)
 			continue;
 
 		WARN_FUNC("indirect %s found in RETPOLINE build",
@@ -3621,7 +3621,7 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio
 	 * In this case we'll find a piece of code (whole function) that is not
 	 * covered by a !section symbol. Ignore them.
 	 */
-	if (!insn->func && lto) {
+	if (!insn->func && opts.lto) {
 		int size = find_symbol_hole_containing(insn->sec, insn->offset);
 		unsigned long end = insn->offset + size;
 
@@ -3728,7 +3728,7 @@ static int validate_symbol(struct objtool_file *file, struct section *sec,
 	state->uaccess = sym->uaccess_safe;
 
 	ret = validate_branch(file, insn->func, insn, *state);
-	if (ret && backtrace)
+	if (ret && opts.backtrace)
 		BT_FUNC("<=== (sym)", insn);
 	return ret;
 }
@@ -3853,12 +3853,12 @@ int check(struct objtool_file *file)
 {
 	int ret, warnings = 0;
 
-	if (lto && !(vmlinux || module)) {
+	if (opts.lto && !(opts.vmlinux || opts.module)) {
 		fprintf(stderr, "--lto requires: --vmlinux or --module\n");
 		return 1;
 	}
 
-	if (ibt && !lto) {
+	if (opts.ibt && !opts.lto) {
 		fprintf(stderr, "--ibt requires: --lto\n");
 		return 1;
 	}
@@ -3883,7 +3883,7 @@ int check(struct objtool_file *file)
 	if (list_empty(&file->insn_list))
 		goto out;
 
-	if (vmlinux && !lto) {
+	if (opts.vmlinux && !opts.lto) {
 		ret = validate_vmlinux_functions(file);
 		if (ret < 0)
 			goto out;
@@ -3892,7 +3892,7 @@ int check(struct objtool_file *file)
 		goto out;
 	}
 
-	if (retpoline) {
+	if (opts.retpoline) {
 		ret = validate_retpoline(file);
 		if (ret < 0)
 			return ret;
@@ -3909,7 +3909,7 @@ int check(struct objtool_file *file)
 		goto out;
 	warnings += ret;
 
-	if (ibt) {
+	if (opts.ibt) {
 		ret = validate_ibt(file);
 		if (ret < 0)
 			goto out;
@@ -3928,28 +3928,28 @@ int check(struct objtool_file *file)
 		goto out;
 	warnings += ret;
 
-	if (retpoline) {
+	if (opts.retpoline) {
 		ret = create_retpoline_sites_sections(file);
 		if (ret < 0)
 			goto out;
 		warnings += ret;
 	}
 
-	if (mcount) {
+	if (opts.mcount) {
 		ret = create_mcount_loc_sections(file);
 		if (ret < 0)
 			goto out;
 		warnings += ret;
 	}
 
-	if (ibt) {
+	if (opts.ibt) {
 		ret = create_ibt_endbr_seal_sections(file);
 		if (ret < 0)
 			goto out;
 		warnings += ret;
 	}
 
-	if (stats) {
+	if (opts.stats) {
 		printf("nr_insns_visited: %ld\n", nr_insns_visited);
 		printf("nr_cfi: %ld\n", nr_cfi);
 		printf("nr_cfi_reused: %ld\n", nr_cfi_reused);
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index ebf2ba5755c1..0f6fa372e10e 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -355,7 +355,7 @@ static int read_sections(struct elf *elf)
 		elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
 	}
 
-	if (stats) {
+	if (opts.stats) {
 		printf("nr_sections: %lu\n", (unsigned long)sections_nr);
 		printf("section_bits: %d\n", elf->section_bits);
 	}
@@ -475,7 +475,7 @@ static int read_symbols(struct elf *elf)
 		elf_add_symbol(elf, sym);
 	}
 
-	if (stats) {
+	if (opts.stats) {
 		printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
 		printf("symbol_bits: %d\n", elf->symbol_bits);
 	}
@@ -843,7 +843,7 @@ static int read_relocs(struct elf *elf)
 		tot_reloc += nr_reloc;
 	}
 
-	if (stats) {
+	if (opts.stats) {
 		printf("max_reloc: %lu\n", max_reloc);
 		printf("tot_reloc: %lu\n", tot_reloc);
 		printf("reloc_bits: %d\n", elf->reloc_bits);
@@ -1222,7 +1222,7 @@ int elf_write(struct elf *elf)
 	struct section *sec;
 	Elf_Scn *s;
 
-	if (dryrun)
+	if (opts.dryrun)
 		return 0;
 
 	/* Update changed relocation sections and section headers: */
diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
index c39dbfaef6dc..87c1a7351e3c 100644
--- a/tools/objtool/include/objtool/builtin.h
+++ b/tools/objtool/include/objtool/builtin.h
@@ -8,9 +8,29 @@
 #include <subcmd/parse-options.h>
 
 extern const struct option check_options[];
-extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats,
-	    lto, vmlinux, mcount, noinstr, backup, sls, dryrun,
-	    ibt;
+
+struct opts {
+	/* actions: */
+	bool ibt;
+	bool mcount;
+	bool noinstr;
+	bool retpoline;
+	bool sls;
+	bool uaccess;
+
+	/* options: */
+	bool backtrace;
+	bool backup;
+	bool dryrun;
+	bool lto;
+	bool module;
+	bool no_fp;
+	bool no_unreachable;
+	bool stats;
+	bool vmlinux;
+};
+
+extern struct opts opts;
 
 extern int cmd_parse_options(int argc, const char **argv, const char * const usage[]);
 
diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index 843ff3c2f28e..a0f3d3c9558d 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -118,7 +118,7 @@ struct objtool_file *objtool_open_read(const char *_objname)
 	if (!file.elf)
 		return NULL;
 
-	if (backup && !objtool_create_backup(objname)) {
+	if (opts.backup && !objtool_create_backup(objname)) {
 		WARN("can't create backup file");
 		return NULL;
 	}
@@ -129,7 +129,7 @@ struct objtool_file *objtool_open_read(const char *_objname)
 	INIT_LIST_HEAD(&file.static_call_list);
 	INIT_LIST_HEAD(&file.mcount_loc_list);
 	INIT_LIST_HEAD(&file.endbr_list);
-	file.ignore_unreachables = no_unreachable;
+	file.ignore_unreachables = opts.no_unreachable;
 	file.hints = false;
 
 	return &file;
@@ -137,7 +137,7 @@ struct objtool_file *objtool_open_read(const char *_objname)
 
 void objtool_pv_add(struct objtool_file *f, int idx, struct symbol *func)
 {
-	if (!noinstr)
+	if (!opts.noinstr)
 		return;
 
 	if (!f->pv_ops) {
-- 
cgit 


From b51277eb9775ce916f9efd2c51533e481180c1e8 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Mon, 18 Apr 2022 09:50:27 -0700
Subject: objtool: Ditch subcommands

Objtool has a fairly singular focus.  It runs on object files and does
validations and transformations which can be combined in various ways.
The subcommand model has never been a good fit, making it awkward to
combine and remove options.

Remove the "check" and "orc" subcommands in favor of a more traditional
cmdline option model.  This makes it much more flexible to use, and
easier to port individual features to other arches.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/5c61ebf805e90aefc5fa62bc63468ffae53b9df6.1650300597.git.jpoimboe@redhat.com
---
 scripts/Makefile.build                  |  2 +-
 scripts/link-vmlinux.sh                 | 13 ++---
 tools/objtool/Build                     | 12 ++--
 tools/objtool/Makefile                  |  8 +--
 tools/objtool/builtin-check.c           | 56 +++++++++++++++----
 tools/objtool/builtin-orc.c             | 73 -------------------------
 tools/objtool/check.c                   |  8 +++
 tools/objtool/include/objtool/builtin.h |  5 +-
 tools/objtool/objtool.c                 | 97 +--------------------------------
 tools/objtool/weak.c                    |  9 +--
 10 files changed, 72 insertions(+), 211 deletions(-)
 delete mode 100644 tools/objtool/builtin-orc.c

(limited to 'tools/objtool/objtool.c')

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index dd9d582808d6..116c7272b41c 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -227,9 +227,9 @@ ifdef CONFIG_STACK_VALIDATION
 objtool := $(objtree)/tools/objtool/objtool
 
 objtool_args =								\
-	$(if $(CONFIG_UNWINDER_ORC),orc generate,check)			\
 	$(if $(CONFIG_X86_KERNEL_IBT), --lto --ibt)			\
 	$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount)		\
+	$(if $(CONFIG_UNWINDER_ORC), --orc)				\
 	$(if $(CONFIG_RETPOLINE), --retpoline)				\
 	$(if $(CONFIG_SLS), --sls)					\
 	$(if $(CONFIG_X86_SMAP), --uaccess)				\
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index c6e9fef61b11..f6db79b11573 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -113,9 +113,6 @@ 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_UNWINDER_ORC; then
-			objtoolcmd="orc generate"
-		fi
 
 		if is_enabled CONFIG_X86_KERNEL_IBT; then
 			objtoolopt="${objtoolopt} --ibt"
@@ -125,6 +122,10 @@ objtool_link()
 			objtoolopt="${objtoolopt} --mcount"
 		fi
 
+		if is_enabled CONFIG_UNWINDER_ORC; then
+			objtoolopt="${objtoolopt} --orc"
+		fi
+
 		objtoolopt="${objtoolopt} --lto"
 	fi
 
@@ -134,10 +135,6 @@ objtool_link()
 
 	if [ -n "${objtoolopt}" ]; then
 
-		if [ -z "${objtoolcmd}" ]; then
-			objtoolcmd="check"
-		fi
-
 		if is_enabled CONFIG_RETPOLINE; then
 			objtoolopt="${objtoolopt} --retpoline"
 		fi
@@ -161,7 +158,7 @@ objtool_link()
 		objtoolopt="${objtoolopt} --vmlinux"
 
 		info OBJTOOL ${1}
-		tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1}
+		tools/objtool/objtool ${objtoolopt} ${1}
 	fi
 }
 
diff --git a/tools/objtool/Build b/tools/objtool/Build
index b7222d5cc7bc..33f2ee5a46d3 100644
--- a/tools/objtool/Build
+++ b/tools/objtool/Build
@@ -2,17 +2,15 @@ objtool-y += arch/$(SRCARCH)/
 
 objtool-y += weak.o
 
-objtool-$(SUBCMD_CHECK) += check.o
-objtool-$(SUBCMD_CHECK) += special.o
-objtool-$(SUBCMD_ORC) += check.o
-objtool-$(SUBCMD_ORC) += orc_gen.o
-objtool-$(SUBCMD_ORC) += orc_dump.o
-
+objtool-y += check.o
+objtool-y += special.o
 objtool-y += builtin-check.o
-objtool-y += builtin-orc.o
 objtool-y += elf.o
 objtool-y += objtool.o
 
+objtool-$(BUILD_ORC) += orc_gen.o
+objtool-$(BUILD_ORC) += orc_dump.o
+
 objtool-y += libstring.o
 objtool-y += libctype.o
 objtool-y += str_error_r.o
diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
index 0dbd397f319d..061cf1cd42c4 100644
--- a/tools/objtool/Makefile
+++ b/tools/objtool/Makefile
@@ -39,15 +39,13 @@ CFLAGS += $(if $(elfshdr),,-DLIBELF_USE_DEPRECATED)
 
 AWK = awk
 
-SUBCMD_CHECK := n
-SUBCMD_ORC := n
+BUILD_ORC := n
 
 ifeq ($(SRCARCH),x86)
-	SUBCMD_CHECK := y
-	SUBCMD_ORC := y
+	BUILD_ORC := y
 endif
 
-export SUBCMD_CHECK SUBCMD_ORC
+export BUILD_ORC
 export srctree OUTPUT CFLAGS SRCARCH AWK
 include $(srctree)/tools/build/Makefile.include
 
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index bc447b3cd9f2..8c3eed5b67e4 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -3,16 +3,6 @@
  * Copyright (C) 2015-2017 Josh Poimboeuf <jpoimboe@redhat.com>
  */
 
-/*
- * objtool check:
- *
- * This command analyzes every .o file and ensures the validity of its stack
- * trace metadata.  It enforces a set of rules on asm code and C inline
- * assembly code so that stack traces can be reliable.
- *
- * For more information, see tools/objtool/Documentation/stack-validation.txt.
- */
-
 #include <subcmd/parse-options.h>
 #include <string.h>
 #include <stdlib.h>
@@ -22,7 +12,7 @@
 struct opts opts;
 
 static const char * const check_usage[] = {
-	"objtool check <actions> [<options>] file.o",
+	"objtool <actions> [<options>] file.o",
 	NULL,
 };
 
@@ -31,14 +21,26 @@ static const char * const env_usage[] = {
 	NULL,
 };
 
+static int parse_dump(const struct option *opt, const char *str, int unset)
+{
+	if (!str || !strcmp(str, "orc")) {
+		opts.dump_orc = true;
+		return 0;
+	}
+
+	return -1;
+}
+
 const struct option check_options[] = {
 	OPT_GROUP("Actions:"),
 	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"),
+	OPT_BOOLEAN('o', "orc", &opts.orc, "generate ORC metadata"),
 	OPT_BOOLEAN('r', "retpoline", &opts.retpoline, "validate and annotate retpoline usage"),
 	OPT_BOOLEAN('l', "sls", &opts.sls, "validate straight-line-speculation mitigations"),
 	OPT_BOOLEAN('u', "uaccess", &opts.uaccess, "validate uaccess rules for SMAP"),
+	OPT_CALLBACK_OPTARG(0, "dump", NULL, NULL, "orc", "dump metadata", parse_dump),
 
 	OPT_GROUP("Options:"),
 	OPT_BOOLEAN(0, "backtrace", &opts.backtrace, "unwind on error"),
@@ -81,7 +83,31 @@ int cmd_parse_options(int argc, const char **argv, const char * const usage[])
 	return argc;
 }
 
-int cmd_check(int argc, const char **argv)
+static bool opts_valid(void)
+{
+	if (opts.ibt		||
+	    opts.mcount		||
+	    opts.noinstr	||
+	    opts.orc		||
+	    opts.retpoline	||
+	    opts.sls		||
+	    opts.uaccess) {
+		if (opts.dump_orc) {
+			fprintf(stderr, "--dump can't be combined with other options\n");
+			return false;
+		}
+
+		return true;
+	}
+
+	if (opts.dump_orc)
+		return true;
+
+	fprintf(stderr, "At least one command required\n");
+	return false;
+}
+
+int objtool_run(int argc, const char **argv)
 {
 	const char *objname;
 	struct objtool_file *file;
@@ -90,6 +116,12 @@ int cmd_check(int argc, const char **argv)
 	argc = cmd_parse_options(argc, argv, check_usage);
 	objname = argv[0];
 
+	if (!opts_valid())
+		return 1;
+
+	if (opts.dump_orc)
+		return orc_dump(objname);
+
 	file = objtool_open_read(objname);
 	if (!file)
 		return 1;
diff --git a/tools/objtool/builtin-orc.c b/tools/objtool/builtin-orc.c
deleted file mode 100644
index 17f8b9307738..000000000000
--- a/tools/objtool/builtin-orc.c
+++ /dev/null
@@ -1,73 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
- */
-
-/*
- * objtool orc:
- *
- * This command analyzes a .o file and adds .orc_unwind and .orc_unwind_ip
- * sections to it, which is used by the in-kernel ORC unwinder.
- *
- * This command is a superset of "objtool check".
- */
-
-#include <string.h>
-#include <objtool/builtin.h>
-#include <objtool/objtool.h>
-
-static const char *orc_usage[] = {
-	"objtool orc generate [<options>] file.o",
-	"objtool orc dump file.o",
-	NULL,
-};
-
-int cmd_orc(int argc, const char **argv)
-{
-	const char *objname;
-
-	argc--; argv++;
-	if (argc <= 0)
-		usage_with_options(orc_usage, check_options);
-
-	if (!strncmp(argv[0], "gen", 3)) {
-		struct objtool_file *file;
-		int ret;
-
-		argc = cmd_parse_options(argc, argv, orc_usage);
-		objname = argv[0];
-
-		file = objtool_open_read(objname);
-		if (!file)
-			return 1;
-
-		ret = check(file);
-		if (ret)
-			return ret;
-
-		if (list_empty(&file->insn_list))
-			return 0;
-
-		ret = orc_create(file);
-		if (ret)
-			return ret;
-
-		if (!file->elf->changed)
-			return 0;
-
-		return elf_write(file->elf);
-	}
-
-	if (!strcmp(argv[0], "dump")) {
-		if (argc != 2)
-			usage_with_options(orc_usage, check_options);
-
-		objname = argv[1];
-
-		return orc_dump(objname);
-	}
-
-	usage_with_options(orc_usage, check_options);
-
-	return 0;
-}
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 3362cc3bdf1a..16a6c4b4f6bb 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -3949,6 +3949,14 @@ int check(struct objtool_file *file)
 		warnings += ret;
 	}
 
+	if (opts.orc && !list_empty(&file->insn_list)) {
+		ret = orc_create(file);
+		if (ret < 0)
+			goto out;
+		warnings += ret;
+	}
+
+
 	if (opts.stats) {
 		printf("nr_insns_visited: %ld\n", nr_insns_visited);
 		printf("nr_cfi: %ld\n", nr_cfi);
diff --git a/tools/objtool/include/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h
index 87c1a7351e3c..44548e24473c 100644
--- a/tools/objtool/include/objtool/builtin.h
+++ b/tools/objtool/include/objtool/builtin.h
@@ -11,9 +11,11 @@ extern const struct option check_options[];
 
 struct opts {
 	/* actions: */
+	bool dump_orc;
 	bool ibt;
 	bool mcount;
 	bool noinstr;
+	bool orc;
 	bool retpoline;
 	bool sls;
 	bool uaccess;
@@ -34,7 +36,6 @@ extern struct opts opts;
 
 extern int cmd_parse_options(int argc, const char **argv, const char * const usage[]);
 
-extern int cmd_check(int argc, const char **argv);
-extern int cmd_orc(int argc, const char **argv);
+extern int objtool_run(int argc, const char **argv);
 
 #endif /* _BUILTIN_H */
diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index a0f3d3c9558d..512669ce064c 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -3,16 +3,6 @@
  * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
  */
 
-/*
- * objtool:
- *
- * The 'check' subcmd analyzes every .o file and ensures the validity of its
- * stack trace metadata.  It enforces a set of rules on asm code and C inline
- * assembly code so that stack traces can be reliable.
- *
- * For more information, see tools/objtool/Documentation/stack-validation.txt.
- */
-
 #include <stdio.h>
 #include <stdbool.h>
 #include <string.h>
@@ -26,20 +16,6 @@
 #include <objtool/objtool.h>
 #include <objtool/warn.h>
 
-struct cmd_struct {
-	const char *name;
-	int (*fn)(int, const char **);
-	const char *help;
-};
-
-static const char objtool_usage_string[] =
-	"objtool COMMAND [ARGS]";
-
-static struct cmd_struct objtool_cmds[] = {
-	{"check",	cmd_check,	"Perform stack metadata validation on an object file" },
-	{"orc",		cmd_orc,	"Generate in-place ORC unwind tables for an object file" },
-};
-
 bool help;
 
 const char *objname;
@@ -161,70 +137,6 @@ void objtool_pv_add(struct objtool_file *f, int idx, struct symbol *func)
 	f->pv_ops[idx].clean = false;
 }
 
-static void cmd_usage(void)
-{
-	unsigned int i, longest = 0;
-
-	printf("\n usage: %s\n\n", objtool_usage_string);
-
-	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
-		if (longest < strlen(objtool_cmds[i].name))
-			longest = strlen(objtool_cmds[i].name);
-	}
-
-	puts(" Commands:");
-	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
-		printf("   %-*s   ", longest, objtool_cmds[i].name);
-		puts(objtool_cmds[i].help);
-	}
-
-	printf("\n");
-
-	if (!help)
-		exit(129);
-	exit(0);
-}
-
-static void handle_options(int *argc, const char ***argv)
-{
-	while (*argc > 0) {
-		const char *cmd = (*argv)[0];
-
-		if (cmd[0] != '-')
-			break;
-
-		if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h")) {
-			help = true;
-			break;
-		} else {
-			fprintf(stderr, "Unknown option: %s\n", cmd);
-			cmd_usage();
-		}
-
-		(*argv)++;
-		(*argc)--;
-	}
-}
-
-static void handle_internal_command(int argc, const char **argv)
-{
-	const char *cmd = argv[0];
-	unsigned int i, ret;
-
-	for (i = 0; i < ARRAY_SIZE(objtool_cmds); i++) {
-		struct cmd_struct *p = objtool_cmds+i;
-
-		if (strcmp(p->name, cmd))
-			continue;
-
-		ret = p->fn(argc, argv);
-
-		exit(ret);
-	}
-
-	cmd_usage();
-}
-
 int main(int argc, const char **argv)
 {
 	static const char *UNUSED = "OBJTOOL_NOT_IMPLEMENTED";
@@ -233,14 +145,7 @@ int main(int argc, const char **argv)
 	exec_cmd_init("objtool", UNUSED, UNUSED, UNUSED);
 	pager_init(UNUSED);
 
-	argv++;
-	argc--;
-	handle_options(&argc, &argv);
-
-	if (!argc || help)
-		cmd_usage();
-
-	handle_internal_command(argc, argv);
+	objtool_run(argc, argv);
 
 	return 0;
 }
diff --git a/tools/objtool/weak.c b/tools/objtool/weak.c
index 8314e824db4a..d83f607733b0 100644
--- a/tools/objtool/weak.c
+++ b/tools/objtool/weak.c
@@ -15,17 +15,12 @@
 	return ENOSYS;							\
 })
 
-int __weak check(struct objtool_file *file)
-{
-	UNSUPPORTED("check subcommand");
-}
-
 int __weak orc_dump(const char *_objname)
 {
-	UNSUPPORTED("orc");
+	UNSUPPORTED("ORC");
 }
 
 int __weak orc_create(struct objtool_file *file)
 {
-	UNSUPPORTED("orc");
+	UNSUPPORTED("ORC");
 }
-- 
cgit