Merge tag 'kconfig-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - improve checkpatch for more precise Kconfig code checking

 - clarify effective selects by grouping reverse dependencies in help

 - do not write out '# CONFIG_FOO is not set' from invisible symbols

 - make oldconfig as silent as it should be

 - rename 'silentoldconfig' to 'syncconfig'

 - add unit-test framework and several test cases

 - warn unmet dependency of tristate symbols

 - make unmet dependency warnings readable, removing false positives

 - improve recursive include detection

 - use yylineno to simplify the line number tracking

 - misc cleanups

* tag 'kconfig-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kconfig: use yylineno option instead of manual lineno increments
  kconfig: detect recursive inclusion earlier
  kconfig: remove duplicated file name and lineno of recursive inclusion
  kconfig: do not include both curses.h and ncurses.h for nconfig
  kconfig: make unmet dependency warnings readable
  kconfig: warn unmet direct dependency of tristate symbols selected by y
  kconfig: tests: test if recursive inclusion is detected
  kconfig: tests: test if recursive dependencies are detected
  kconfig: tests: test randconfig for choice in choice
  kconfig: tests: test defconfig when two choices interact
  kconfig: tests: check visibility of tristate choice values in y choice
  kconfig: tests: check unneeded "is not set" with unmet dependency
  kconfig: tests: test if new symbols in choice are asked
  kconfig: tests: test automatic submenu creation
  kconfig: tests: add basic choice tests
  kconfig: tests: add framework for Kconfig unit testing
  kbuild: add PYTHON2 and PYTHON3 variables
  kconfig: remove redundant streamline_config.pl prerequisite
  kconfig: rename silentoldconfig to syncconfig
  kconfig: invoke oldconfig instead of silentoldconfig from local*config
  ...

54 files changed, 1020 insertions, 131 deletions

diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index eb139a17383c..f9bdd02c06a2 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -3,7 +3,7 @@
 # Kernel configuration targets
 # These targets are used from top-level makefile
 
-PHONY += xconfig gconfig menuconfig config silentoldconfig update-po-config \
+PHONY += xconfig gconfig menuconfig config syncconfig update-po-config \
 	localmodconfig localyesconfig
 
 ifdef KBUILD_KCONFIG
@@ -36,22 +36,22 @@ nconfig: $(obj)/nconf
 
 # This has become an internal implementation detail and is now deprecated
 # for external use.
-silentoldconfig: $(obj)/conf
+syncconfig: $(obj)/conf
 	$(Q)mkdir -p include/config include/generated
 	$< $(silent) --$@ $(Kconfig)
 
-localyesconfig localmodconfig: $(obj)/streamline_config.pl $(obj)/conf
+localyesconfig localmodconfig: $(obj)/conf
 	$(Q)mkdir -p include/config include/generated
-	$(Q)perl $< --$@ $(srctree) $(Kconfig) > .tmp.config
+	$(Q)perl $(srctree)/$(src)/streamline_config.pl --$@ $(srctree) $(Kconfig) > .tmp.config
 	$(Q)if [ -f .config ]; then 					\
 			cmp -s .tmp.config .config ||			\
 			(mv -f .config .config.old.1;			\
 			 mv -f .tmp.config .config;			\
-			 $(obj)/conf $(silent) --silentoldconfig $(Kconfig); \
+			 $< $(silent) --oldconfig $(Kconfig);		\
 			 mv -f .config.old.1 .config.old)		\
 	else								\
 			mv -f .tmp.config .config;			\
-			$(obj)/conf $(silent) --silentoldconfig $(Kconfig); \
+			$< $(silent) --oldconfig $(Kconfig);		\
 	fi
 	$(Q)rm -f .tmp.config
 
@@ -86,7 +86,7 @@ PHONY += $(simple-targets)
 $(simple-targets): $(obj)/conf
 	$< $(silent) --$@ $(Kconfig)
 
-PHONY += oldnoconfig savedefconfig defconfig
+PHONY += oldnoconfig silentoldconfig savedefconfig defconfig
 
 # oldnoconfig is an alias of olddefconfig, because people already are dependent
 # on its behavior (sets new symbols to their default value but not 'n') with the
@@ -95,6 +95,13 @@ oldnoconfig: olddefconfig
 	@echo "  WARNING: \"oldnoconfig\" target will be removed after Linux 4.19"
 	@echo "            Please use \"olddefconfig\" instead, which is an alias."
 
+# We do not expect manual invokcation of "silentoldcofig" (or "syncconfig").
+silentoldconfig: syncconfig
+	@echo "  WARNING: \"silentoldconfig\" has been renamed to \"syncconfig\""
+	@echo "            and is now an internal implementation detail."
+	@echo "            What you want is probably \"oldconfig\"."
+	@echo "            \"silentoldconfig\" will be removed after Linux 4.19"
+
 savedefconfig: $(obj)/conf
 	$< $(silent) --$@=defconfig $(Kconfig)
 
@@ -133,6 +140,14 @@ PHONY += tinyconfig
 tinyconfig:
 	$(Q)$(MAKE) -f $(srctree)/Makefile allnoconfig tiny.config
 
+# CHECK: -o cache_dir=<path> working?
+PHONY += testconfig
+testconfig: $(obj)/conf
+	$(PYTHON3) -B -m pytest $(srctree)/$(src)/tests \
+	-o cache_dir=$(abspath $(obj)/tests/.cache) \
+	$(if $(findstring 1,$(KBUILD_VERBOSE)),--capture=no)
+clean-dirs += tests/.cache
+
 # Help text used by make help
 help:
 	@echo  '  config	  - Update current config utilising a line-oriented program'
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index 822dc51923d6..4e08121a35fb 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -23,7 +23,7 @@ static void check_conf(struct menu *menu);
 
 enum input_mode {
 	oldaskconfig,
-	silentoldconfig,
+	syncconfig,
 	oldconfig,
 	allnoconfig,
 	allyesconfig,
@@ -100,7 +100,7 @@ static int conf_askvalue(struct symbol *sym, const char *def)
 
 	switch (input_mode) {
 	case oldconfig:
-	case silentoldconfig:
+	case syncconfig:
 		if (sym_has_value(sym)) {
 			printf("%s\n", def);
 			return 0;
@@ -293,7 +293,7 @@ static int conf_choice(struct menu *menu)
 		printf("[1-%d?]: ", cnt);
 		switch (input_mode) {
 		case oldconfig:
-		case silentoldconfig:
+		case syncconfig:
 			if (!is_new) {
 				cnt = def;
 				printf("%d\n", cnt);
@@ -358,10 +358,11 @@ static void conf(struct menu *menu)
 
 		switch (prop->type) {
 		case P_MENU:
-			if ((input_mode == silentoldconfig ||
-			     input_mode == listnewconfig ||
-			     input_mode == olddefconfig) &&
-			    rootEntry != menu) {
+			/*
+			 * Except in oldaskconfig mode, we show only menus that
+			 * contain new symbols.
+			 */
+			if (input_mode != oldaskconfig && rootEntry != menu) {
 				check_conf(menu);
 				return;
 			}
@@ -424,7 +425,7 @@ static void check_conf(struct menu *menu)
 				if (sym->name && !sym_is_choice_value(sym)) {
 					printf("%s%s\n", CONFIG_, sym->name);
 				}
-			} else if (input_mode != olddefconfig) {
+			} else {
 				if (!conf_cnt++)
 					printf(_("*\n* Restart config...\n*\n"));
 				rootEntry = menu_get_parent_menu(menu);
@@ -440,7 +441,7 @@ static void check_conf(struct menu *menu)
 static struct option long_opts[] = {
 	{"oldaskconfig",    no_argument,       NULL, oldaskconfig},
 	{"oldconfig",       no_argument,       NULL, oldconfig},
-	{"silentoldconfig", no_argument,       NULL, silentoldconfig},
+	{"syncconfig",      no_argument,       NULL, syncconfig},
 	{"defconfig",       optional_argument, NULL, defconfig},
 	{"savedefconfig",   required_argument, NULL, savedefconfig},
 	{"allnoconfig",     no_argument,       NULL, allnoconfig},
@@ -467,8 +468,8 @@ static void conf_usage(const char *progname)
 	printf("  --listnewconfig         List new options\n");
 	printf("  --oldaskconfig          Start a new configuration using a line-oriented program\n");
 	printf("  --oldconfig             Update a configuration using a provided .config as base\n");
-	printf("  --silentoldconfig       Similar to oldconfig but generates configuration in\n"
-	       "                          include/{generated/,config/} (oldconfig used to be more verbose)\n");
+	printf("  --syncconfig            Similar to oldconfig but generates configuration in\n"
+	       "                          include/{generated/,config/}\n");
 	printf("  --olddefconfig          Same as oldconfig but sets new symbols to their default value\n");
 	printf("  --oldnoconfig           An alias of olddefconfig\n");
 	printf("  --defconfig <file>      New config with default defined in <file>\n");
@@ -500,7 +501,7 @@ int main(int ac, char **av)
 		}
 		input_mode = (enum input_mode)opt;
 		switch (opt) {
-		case silentoldconfig:
+		case syncconfig:
 			sync_kconfig = 1;
 			break;
 		case defconfig:
@@ -582,7 +583,7 @@ int main(int ac, char **av)
 		}
 		break;
 	case savedefconfig:
-	case silentoldconfig:
+	case syncconfig:
 	case oldaskconfig:
 	case oldconfig:
 	case listnewconfig:
@@ -662,24 +663,24 @@ int main(int ac, char **av)
 	case oldaskconfig:
 		rootEntry = &rootmenu;
 		conf(&rootmenu);
-		input_mode = silentoldconfig;
+		input_mode = oldconfig;
 		/* fall through */
 	case oldconfig:
 	case listnewconfig:
-	case olddefconfig:
-	case silentoldconfig:
+	case syncconfig:
 		/* Update until a loop caused no more changes */
 		do {
 			conf_cnt = 0;
 			check_conf(&rootmenu);
-		} while (conf_cnt &&
-			 (input_mode != listnewconfig &&
-			  input_mode != olddefconfig));
+		} while (conf_cnt);
+		break;
+	case olddefconfig:
+	default:
 		break;
 	}
 
 	if (sync_kconfig) {
-		/* silentoldconfig is used during the build so we shall update autoconf.
+		/* syncconfig is used during the build so we shall update autoconf.
 		 * All other commands are only used to generate a config.
 		 */
 		if (conf_get_changed() && conf_write(NULL)) {
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
index d45381986ac7..e1a39e90841d 100644
--- a/scripts/kconfig/expr.c
+++ b/scripts/kconfig/expr.c
@@ -1137,49 +1137,9 @@ static int expr_compare_type(enum expr_type t1, enum expr_type t2)
 	return 0;
 }
 
-static inline struct expr *
-expr_get_leftmost_symbol(const struct expr *e)
-{
-
-	if (e == NULL)
-		return NULL;
-
-	while (e->type != E_SYMBOL)
-		e = e->left.expr;
-
-	return expr_copy(e);
-}
-
-/*
- * Given expression `e1' and `e2', returns the leaf of the longest
- * sub-expression of `e1' not containing 'e2.
- */
-struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2)
-{
-	struct expr *ret;
-
-	switch (e1->type) {
-	case E_OR:
-		return expr_alloc_and(
-		    expr_simplify_unmet_dep(e1->left.expr, e2),
-		    expr_simplify_unmet_dep(e1->right.expr, e2));
-	case E_AND: {
-		struct expr *e;
-		e = expr_alloc_and(expr_copy(e1), expr_copy(e2));
-		e = expr_eliminate_dups(e);
-		ret = (!expr_eq(e, e1)) ? e1 : NULL;
-		expr_free(e);
-		break;
-		}
-	default:
-		ret = e1;
-		break;
-	}
-
-	return expr_get_leftmost_symbol(ret);
-}
-
-static void __expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken, bool revdep)
+void expr_print(struct expr *e,
+		void (*fn)(void *, struct symbol *, const char *),
+		void *data, int prevtoken)
 {
 	if (!e) {
 		fn(data, NULL, "y");
@@ -1234,14 +1194,9 @@ static void __expr_print(struct expr *e, void (*fn)(void *, struct symbol *, con
 		fn(data, e->right.sym, e->right.sym->name);
 		break;
 	case E_OR:
-		if (revdep && e->left.expr->type != E_OR)
-			fn(data, NULL, "\n  - ");
-		__expr_print(e->left.expr, fn, data, E_OR, revdep);
-		if (revdep)
-			fn(data, NULL, "\n  - ");
-		else
-			fn(data, NULL, " || ");
-		__expr_print(e->right.expr, fn, data, E_OR, revdep);
+		expr_print(e->left.expr, fn, data, E_OR);
+		fn(data, NULL, " || ");
+		expr_print(e->right.expr, fn, data, E_OR);
 		break;
 	case E_AND:
 		expr_print(e->left.expr, fn, data, E_AND);
@@ -1274,11 +1229,6 @@ static void __expr_print(struct expr *e, void (*fn)(void *, struct symbol *, con
 		fn(data, NULL, ")");
 }
 
-void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken)
-{
-	__expr_print(e, fn, data, prevtoken, false);
-}
-
 static void expr_print_file_helper(void *data, struct symbol *sym, const char *str)
 {
 	xfwrite(str, strlen(str), 1, data);
@@ -1329,7 +1279,27 @@ void expr_gstr_print(struct expr *e, struct gstr *gs)
  * line with a minus. This makes expressions much easier to read.
  * Suitable for reverse dependency expressions.
  */
-void expr_gstr_print_revdep(struct expr *e, struct gstr *gs)
+static void expr_print_revdep(struct expr *e,
+			      void (*fn)(void *, struct symbol *, const char *),
+			      void *data, tristate pr_type, const char **title)
+{
+	if (e->type == E_OR) {
+		expr_print_revdep(e->left.expr, fn, data, pr_type, title);
+		expr_print_revdep(e->right.expr, fn, data, pr_type, title);
+	} else if (expr_calc_value(e) == pr_type) {
+		if (*title) {
+			fn(data, NULL, *title);
+			*title = NULL;
+		}
+
+		fn(data, NULL, "  - ");
+		expr_print(e, fn, data, E_NONE);
+		fn(data, NULL, "\n");
+	}
+}
+
+void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
+			    tristate pr_type, const char *title)
 {
-	__expr_print(e, expr_print_gstr_helper, gs, E_NONE, true);
+	expr_print_revdep(e, expr_print_gstr_helper, gs, pr_type, &title);
 }
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index c16e82e302a2..94a383b21df6 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -305,12 +305,12 @@ struct expr *expr_transform(struct expr *e);
 int expr_contains_symbol(struct expr *dep, struct symbol *sym);
 bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
 struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
-struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2);
 
 void expr_fprint(struct expr *e, FILE *out);
 struct gstr; /* forward */
 void expr_gstr_print(struct expr *e, struct gstr *gs);
-void expr_gstr_print_revdep(struct expr *e, struct gstr *gs);
+void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
+			    tristate pr_type, const char *title);
 
 static inline int expr_is_yes(struct expr *e)
 {
diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h
index 2d5ec2d0e952..f4394af6e4b8 100644
--- a/scripts/kconfig/lkc.h
+++ b/scripts/kconfig/lkc.h
@@ -68,6 +68,7 @@ struct kconf_id {
 	enum symbol_type stype;
 };
 
+extern int yylineno;
 void zconfdump(FILE *out);
 void zconf_starthelp(void);
 FILE *zconf_fopen(const char *name);
diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 36cd3e1f1c28..5c5c1374b151 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -828,16 +828,16 @@ static void get_symbol_str(struct gstr *r, struct symbol *sym,
 
 	get_symbol_props_str(r, sym, P_SELECT, _("  Selects: "));
 	if (sym->rev_dep.expr) {
-		str_append(r, _("  Selected by: "));
-		expr_gstr_print_revdep(sym->rev_dep.expr, r);
-		str_append(r, "\n");
+		expr_gstr_print_revdep(sym->rev_dep.expr, r, yes, "  Selected by [y]:\n");
+		expr_gstr_print_revdep(sym->rev_dep.expr, r, mod, "  Selected by [m]:\n");
+		expr_gstr_print_revdep(sym->rev_dep.expr, r, no, "  Selected by [n]:\n");
 	}
 
 	get_symbol_props_str(r, sym, P_IMPLY, _("  Implies: "));
 	if (sym->implied.expr) {
-		str_append(r, _("  Implied by: "));
-		expr_gstr_print_revdep(sym->implied.expr, r);
-		str_append(r, "\n");
+		expr_gstr_print_revdep(sym->implied.expr, r, yes, "  Implied by [y]:\n");
+		expr_gstr_print_revdep(sym->implied.expr, r, mod, "  Implied by [m]:\n");
+		expr_gstr_print_revdep(sym->implied.expr, r, no, "  Implied by [n]:\n");
 	}
 
 	str_append(r, "\n\n");
diff --git a/scripts/kconfig/nconf.h b/scripts/kconfig/nconf.h
index 0d5261705ef5..9f6f21d3b0d4 100644
--- a/scripts/kconfig/nconf.h
+++ b/scripts/kconfig/nconf.h
@@ -15,7 +15,7 @@
 #include <string.h>
 #include <unistd.h>
 #include <locale.h>
-#include <curses.h>
+#include <ncurses.h>
 #include <menu.h>
 #include <panel.h>
 #include <form.h>
@@ -24,8 +24,6 @@
 #include <time.h>
 #include <sys/time.h>
 
-#include "ncurses.h"
-
 #define max(a, b) ({\
 		typeof(a) _a = a;\
 		typeof(b) _b = b;\
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 2220bc4b051b..f0b2e3b3102d 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -243,7 +243,7 @@ static void sym_calc_visibility(struct symbol *sym)
 	tri = yes;
 	if (sym->dir_dep.expr)
 		tri = expr_calc_value(sym->dir_dep.expr);
-	if (tri == mod)
+	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
 		tri = yes;
 	if (sym->dir_dep.tri != tri) {
 		sym->dir_dep.tri = tri;
@@ -333,6 +333,27 @@ static struct symbol *sym_calc_choice(struct symbol *sym)
 	return def_sym;
 }
 
+static void sym_warn_unmet_dep(struct symbol *sym)
+{
+	struct gstr gs = str_new();
+
+	str_printf(&gs,
+		   "\nWARNING: unmet direct dependencies detected for %s\n",
+		   sym->name);
+	str_printf(&gs,
+		   "  Depends on [%c]: ",
+		   sym->dir_dep.tri == mod ? 'm' : 'n');
+	expr_gstr_print(sym->dir_dep.expr, &gs);
+	str_printf(&gs, "\n");
+
+	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
+			       "  Selected by [y]:\n");
+	expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
+			       "  Selected by [m]:\n");
+
+	fputs(str_get(&gs), stderr);
+}
+
 void sym_calc_value(struct symbol *sym)
 {
 	struct symbol_value newval, oldval;
@@ -403,9 +424,10 @@ void sym_calc_value(struct symbol *sym)
 			if (!sym_is_choice(sym)) {
 				prop = sym_get_default_prop(sym);
 				if (prop) {
-					sym->flags |= SYMBOL_WRITE;
 					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
 							      prop->visible.tri);
+					if (newval.tri != no)
+						sym->flags |= SYMBOL_WRITE;
 				}
 				if (sym->implied.tri != no) {
 					sym->flags |= SYMBOL_WRITE;
@@ -413,18 +435,8 @@ void sym_calc_value(struct symbol *sym)
 				}
 			}
 		calc_newval:
-			if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
-				struct expr *e;
-				e = expr_simplify_unmet_dep(sym->rev_dep.expr,
-				    sym->dir_dep.expr);
-				fprintf(stderr, "warning: (");
-				expr_fprint(e, stderr);
-				fprintf(stderr, ") selects %s which has unmet direct dependencies (",
-					sym->name);
-				expr_fprint(sym->dir_dep.expr, stderr);
-				fprintf(stderr, ")\n");
-				expr_free(e);
-			}
+			if (sym->dir_dep.tri < sym->rev_dep.tri)
+				sym_warn_unmet_dep(sym);
 			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
 		}
 		if (newval.tri == mod &&
diff --git a/scripts/kconfig/tests/auto_submenu/Kconfig b/scripts/kconfig/tests/auto_submenu/Kconfig
new file mode 100644
index 000000000000..c17bf2caa7e6
--- /dev/null
+++ b/scripts/kconfig/tests/auto_submenu/Kconfig
@@ -0,0 +1,50 @@
+config A
+	bool "A"
+	default y
+
+config A0
+	bool "A0"
+	depends on A
+	default y
+	help
+	  This depends on A, so should be a submenu of A.
+
+config A0_0
+	bool "A1_0"
+	depends on A0
+	help
+	  Submenus are created recursively.
+	  This should be a submenu of A0.
+
+config A1
+	bool "A1"
+	depends on A
+	default y
+	help
+	  This should line up with A0.
+
+choice
+	prompt "choice"
+	depends on A1
+	help
+	  Choice should become a submenu as well.
+
+config A1_0
+	bool "A1_0"
+
+config A1_1
+	bool "A1_1"
+
+endchoice
+
+config B
+	bool "B"
+	help
+	  This is independent of A.
+
+config C
+	bool "C"
+	depends on A
+	help
+	  This depends on A, but not a consecutive item, so can/should not
+	  be a submenu.
diff --git a/scripts/kconfig/tests/auto_submenu/__init__.py b/scripts/kconfig/tests/auto_submenu/__init__.py
new file mode 100644
index 000000000000..32e79b85faeb
--- /dev/null
+++ b/scripts/kconfig/tests/auto_submenu/__init__.py
@@ -0,0 +1,12 @@
+"""
+Create submenu for symbols that depen