Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 797 insertions, 0 deletions

diff --git a/scripts/kconfig/parser.y b/scripts/kconfig/parser.y
new file mode 100644
index 000000000..5fb6f07b6
--- /dev/null
+++ b/scripts/kconfig/parser.y
@@ -0,0 +1,797 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
+ */
+%{
+
+#include <ctype.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include <xalloc.h>
+#include "lkc.h"
+#include "internal.h"
+#include "preprocess.h"
+
+#define printd(mask, fmt...) if (cdebug & (mask)) printf(fmt)
+
+#define PRINTD		0x0001
+#define DEBUG_PARSE	0x0002
+
+int cdebug = PRINTD;
+
+static void yyerror(const char *err);
+static void zconf_error(const char *err, ...);
+static bool zconf_endtoken(const char *tokenname,
+			   const char *expected_tokenname);
+
+struct menu *current_menu, *current_entry, *current_choice;
+
+%}
+
+%union
+{
+	char *string;
+	struct symbol *symbol;
+	struct expr *expr;
+	struct menu *menu;
+	enum symbol_type type;
+	enum variable_flavor flavor;
+}
+
+%token <string> T_HELPTEXT
+%token <string> T_WORD
+%token <string> T_WORD_QUOTE
+%token T_BOOL
+%token T_CHOICE
+%token T_CLOSE_PAREN
+%token T_COLON_EQUAL
+%token T_COMMENT
+%token T_CONFIG
+%token T_DEFAULT
+%token T_DEF_BOOL
+%token T_DEF_TRISTATE
+%token T_DEPENDS
+%token T_ENDCHOICE
+%token T_ENDIF
+%token T_ENDMENU
+%token T_HELP
+%token T_HEX
+%token T_IF
+%token T_IMPLY
+%token T_INT
+%token T_MAINMENU
+%token T_MENU
+%token T_MENUCONFIG
+%token T_MODULES
+%token T_ON
+%token T_OPEN_PAREN
+%token T_PLUS_EQUAL
+%token T_PROMPT
+%token T_RANGE
+%token T_SELECT
+%token T_SOURCE
+%token T_STRING
+%token T_TRANSITIONAL
+%token T_TRISTATE
+%token T_VISIBLE
+%token T_EOL
+%token <string> T_ASSIGN_VAL
+
+%left T_OR
+%left T_AND
+%left T_EQUAL T_UNEQUAL
+%left T_LESS T_LESS_EQUAL T_GREATER T_GREATER_EQUAL
+%nonassoc T_NOT
+
+%type <symbol> nonconst_symbol
+%type <symbol> symbol
+%type <type> type default
+%type <expr> expr
+%type <expr> if_expr
+%type <string> end
+%type <menu> if_entry menu_entry choice_entry
+%type <string> assign_val
+%type <flavor> assign_op
+
+%destructor {
+	fprintf(stderr, "%s:%d: missing end statement for this entry\n",
+		$$->filename, $$->lineno);
+	if (current_menu == $$)
+		menu_end_menu();
+} if_entry menu_entry choice_entry
+
+%%
+input: mainmenu_stmt stmt_list | stmt_list;
+
+/* mainmenu entry */
+
+mainmenu_stmt: T_MAINMENU T_WORD_QUOTE T_EOL
+{
+	menu_add_prompt(P_MENU, $2, NULL);
+};
+
+stmt_list:
+	  /* empty */
+	| stmt_list assignment_stmt
+	| stmt_list choice_stmt
+	| stmt_list comment_stmt
+	| stmt_list config_stmt
+	| stmt_list if_stmt
+	| stmt_list menu_stmt
+	| stmt_list menuconfig_stmt
+	| stmt_list source_stmt
+	| stmt_list T_WORD error T_EOL	{ zconf_error("unknown statement \"%s\"", $2); }
+	| stmt_list error T_EOL		{ zconf_error("invalid statement"); }
+;
+
+stmt_list_in_choice:
+	  /* empty */
+	| stmt_list_in_choice comment_stmt
+	| stmt_list_in_choice config_stmt
+	| stmt_list_in_choice if_stmt_in_choice
+	| stmt_list_in_choice error T_EOL	{ zconf_error("invalid statement"); }
+;
+
+/* config/menuconfig entry */
+
+config_entry_start: T_CONFIG nonconst_symbol T_EOL
+{
+	menu_add_entry($2, M_NORMAL);
+	printd(DEBUG_PARSE, "%s:%d:config %s\n", cur_filename, cur_lineno, $2->name);
+};
+
+config_stmt: config_entry_start config_option_list
+{
+	if (current_choice) {
+		if (!current_entry->prompt) {
+			fprintf(stderr, "%s:%d: error: choice member must have a prompt\n",
+				current_entry->filename, current_entry->lineno);
+			yynerrs++;
+		}
+
+		if (current_entry->sym->type != S_BOOLEAN) {
+			fprintf(stderr, "%s:%d: error: choice member must be bool\n",
+				current_entry->filename, current_entry->lineno);
+			yynerrs++;
+		}
+
+		list_add_tail(&current_entry->sym->choice_link,
+			      &current_choice->choice_members);
+	}
+
+	printd(DEBUG_PARSE, "%s:%d:endconfig\n", cur_filename, cur_lineno);
+};
+
+menuconfig_entry_start: T_MENUCONFIG nonconst_symbol T_EOL
+{
+	menu_add_entry($2, M_MENU);
+	printd(DEBUG_PARSE, "%s:%d:menuconfig %s\n", cur_filename, cur_lineno, $2->name);
+};
+
+menuconfig_stmt: menuconfig_entry_start config_option_list
+{
+	if (current_entry->prompt)
+		current_entry->prompt->type = P_MENU;
+	else
+		zconf_error("menuconfig statement without prompt");
+	printd(DEBUG_PARSE, "%s:%d:endconfig\n", cur_filename, cur_lineno);
+};
+
+config_option_list:
+	  /* empty */
+	| config_option_list config_option
+	| config_option_list depends
+	| config_option_list help
+;
+
+config_option: type prompt_stmt_opt T_EOL
+{
+	menu_set_type($1);
+	printd(DEBUG_PARSE, "%s:%d:type(%u)\n", cur_filename, cur_lineno, $1);
+};
+
+config_option: T_PROMPT T_WORD_QUOTE if_expr T_EOL
+{
+	menu_add_prompt(P_PROMPT, $2, $3);
+	printd(DEBUG_PARSE, "%s:%d:prompt\n", cur_filename, cur_lineno);
+};
+
+config_option: T_TRANSITIONAL T_EOL
+{
+	current_entry->sym->flags |= SYMBOL_TRANS;
+	printd(DEBUG_PARSE, "%s:%d:transitional\n", cur_filename, cur_lineno);
+};
+
+config_option: default expr if_expr T_EOL
+{
+	menu_add_expr(P_DEFAULT, $2, $3);
+	if ($1 != S_UNKNOWN)
+		menu_set_type($1);
+	printd(DEBUG_PARSE, "%s:%d:default(%u)\n", cur_filename, cur_lineno,
+		$1);
+};
+
+config_option: T_SELECT nonconst_symbol if_expr T_EOL
+{
+	menu_add_symbol(P_SELECT, $2, $3);
+	printd(DEBUG_PARSE, "%s:%d:select\n", cur_filename, cur_lineno);
+};
+
+config_option: T_IMPLY nonconst_symbol if_expr T_EOL
+{
+	menu_add_symbol(P_IMPLY, $2, $3);
+	printd(DEBUG_PARSE, "%s:%d:imply\n", cur_filename, cur_lineno);
+};
+
+config_option: T_RANGE symbol symbol if_expr T_EOL
+{
+	menu_add_expr(P_RANGE, expr_alloc_comp(E_RANGE,$2, $3), $4);
+	printd(DEBUG_PARSE, "%s:%d:range\n", cur_filename, cur_lineno);
+};
+
+config_option: T_MODULES T_EOL
+{
+	if (modules_sym)
+		zconf_error("symbol '%s' redefines option 'modules' already defined by symbol '%s'",
+			    current_entry->sym->name, modules_sym->name);
+	modules_sym = current_entry->sym;
+};
+
+/* choice entry */
+
+choice: T_CHOICE T_EOL
+{
+	struct symbol *sym = sym_lookup(NULL, 0);
+
+	menu_add_entry(sym, M_CHOICE);
+	menu_set_type(S_BOOLEAN);
+	INIT_LIST_HEAD(&current_entry->choice_members);
+
+	printd(DEBUG_PARSE, "%s:%d:choice\n", cur_filename, cur_lineno);
+};
+
+choice_entry: choice choice_option_list
+{
+	if (!current_entry->prompt) {
+		fprintf(stderr, "%s:%d: error: choice must have a prompt\n",
+			current_entry->filename, current_entry->lineno);
+		yynerrs++;
+	}
+
+	$$ = menu_add_menu();
+
+	current_choice = current_entry;
+};
+
+choice_end: end
+{
+	current_choice = NULL;
+
+	if (zconf_endtoken($1, "choice")) {
+		menu_end_menu();
+		printd(DEBUG_PARSE, "%s:%d:endchoice\n", cur_filename, cur_lineno);
+	}
+};
+
+choice_stmt: choice_entry stmt_list_in_choice choice_end
+;
+
+choice_option_list:
+	  /* empty */
+	| choice_option_list choice_option
+	| choice_option_list depends
+	| choice_option_list help
+;
+
+choice_option: T_PROMPT T_WORD_QUOTE if_expr T_EOL
+{
+	menu_add_prompt(P_PROMPT, $2, $3);
+	printd(DEBUG_PARSE, "%s:%d:prompt\n", cur_filename, cur_lineno);
+};
+
+choice_option: T_DEFAULT nonconst_symbol if_expr T_EOL
+{
+	menu_add_symbol(P_DEFAULT, $2, $3);
+	printd(DEBUG_PARSE, "%s:%d:default\n", cur_filename, cur_lineno);
+};
+
+type:
+	  T_BOOL		{ $$ = S_BOOLEAN; }
+	| T_TRISTATE		{ $$ = S_TRISTATE; }
+	| T_INT			{ $$ = S_INT; }
+	| T_HEX			{ $$ = S_HEX; }
+	| T_STRING		{ $$ = S_STRING; }
+
+default:
+	  T_DEFAULT		{ $$ = S_UNKNOWN; }
+	| T_DEF_BOOL		{ $$ = S_BOOLEAN; }
+	| T_DEF_TRISTATE	{ $$ = S_TRISTATE; }
+
+/* if entry */
+
+if_entry: T_IF expr T_EOL
+{
+	printd(DEBUG_PARSE, "%s:%d:if\n", cur_filename, cur_lineno);
+	menu_add_entry(NULL, M_IF);
+	menu_add_dep($2, NULL);
+	$$ = menu_add_menu();
+};
+
+if_end: end
+{
+	if (zconf_endtoken($1, "if")) {
+		menu_end_menu();
+		printd(DEBUG_PARSE, "%s:%d:endif\n", cur_filename, cur_lineno);
+	}
+};
+
+if_stmt: if_entry stmt_list if_end
+;
+
+if_stmt_in_choice: if_entry stmt_list_in_choice if_end
+;
+
+/* menu entry */
+
+menu: T_MENU T_WORD_QUOTE T_EOL
+{
+	menu_add_entry(NULL, M_MENU);
+	menu_add_prompt(P_MENU, $2, NULL);
+	printd(DEBUG_PARSE, "%s:%d:menu\n", cur_filename, cur_lineno);
+};
+
+menu_entry: menu menu_option_list
+{
+	$$ = menu_add_menu();
+};
+
+menu_end: end
+{
+	if (zconf_endtoken($1, "menu")) {
+		menu_end_menu();
+		printd(DEBUG_PARSE, "%s:%d:endmenu\n", cur_filename, cur_lineno);
+	}
+};
+
+menu_stmt: menu_entry stmt_list menu_end
+;
+
+menu_option_list:
+	  /* empty */
+	| menu_option_list visible
+	| menu_option_list depends
+;
+
+source_stmt: T_SOURCE T_WORD_QUOTE T_EOL
+{
+	printd(DEBUG_PARSE, "%s:%d:source %s\n", cur_filename, cur_lineno, $2);
+	zconf_nextfile($2);
+	free($2);
+};
+
+/* comment entry */
+
+comment: T_COMMENT T_WORD_QUOTE T_EOL
+{
+	menu_add_entry(NULL, M_COMMENT);
+	menu_add_prompt(P_COMMENT, $2, NULL);
+	printd(DEBUG_PARSE, "%s:%d:comment\n", cur_filename, cur_lineno);
+};
+
+comment_stmt: comment comment_option_list
+;
+
+comment_option_list:
+	  /* empty */
+	| comment_option_list depends
+;
+
+/* help option */
+
+help_start: T_HELP T_EOL
+{
+	printd(DEBUG_PARSE, "%s:%d:help\n", cur_filename, cur_lineno);
+	zconf_starthelp();
+};
+
+help: help_start T_HELPTEXT
+{
+	if (current_entry->help) {
+		free(current_entry->help);
+		zconf_error("'%s' defined with more than one help text",
+			    current_entry->sym->name ?: "<choice>");
+	}
+
+	/* Is the help text empty or all whitespace? */
+	if ($2[strspn($2, " \f\n\r\t\v")] == '\0')
+		zconf_error("'%s' defined with blank help text",
+			    current_entry->sym->name ?: "<choice>");
+
+	current_entry->help = $2;
+};
+
+/* depends option */
+
+depends: T_DEPENDS T_ON expr if_expr T_EOL
+{
+	menu_add_dep($3, $4);
+	printd(DEBUG_PARSE, "%s:%d:depends on\n", cur_filename, cur_lineno);
+};
+
+/* visibility option */
+visible: T_VISIBLE if_expr T_EOL
+{
+	menu_add_visibility($2);
+};
+
+/* prompt statement */
+
+prompt_stmt_opt:
+	  /* empty */
+	| T_WORD_QUOTE if_expr
+{
+	menu_add_prompt(P_PROMPT, $1, $2);
+};
+
+end:	  T_ENDMENU T_EOL	{ $$ = "menu"; }
+	| T_ENDCHOICE T_EOL	{ $$ = "choice"; }
+	| T_ENDIF T_EOL		{ $$ = "if"; }
+;
+
+if_expr:  /* empty */			{ $$ = NULL; }
+	| T_IF expr			{ $$ = $2; }
+;
+
+expr:	  symbol				{ $$ = expr_alloc_symbol($1); }
+	| symbol T_LESS symbol			{ $$ = expr_alloc_comp(E_LTH, $1, $3); }
+	| symbol T_LESS_EQUAL symbol		{ $$ = expr_alloc_comp(E_LEQ, $1, $3); }
+	| symbol T_GREATER symbol		{ $$ = expr_alloc_comp(E_GTH, $1, $3); }
+	| symbol T_GREATER_EQUAL symbol		{ $$ = expr_alloc_comp(E_GEQ, $1, $3); }
+	| symbol T_EQUAL symbol			{ $$ = expr_alloc_comp(E_EQUAL, $1, $3); }
+	| symbol T_UNEQUAL symbol		{ $$ = expr_alloc_comp(E_UNEQUAL, $1, $3); }
+	| T_OPEN_PAREN expr T_CLOSE_PAREN	{ $$ = $2; }
+	| T_NOT expr				{ $$ = expr_alloc_one(E_NOT, $2); }
+	| expr T_OR expr			{ $$ = expr_alloc_two(E_OR, $1, $3); }
+	| expr T_AND expr			{ $$ = expr_alloc_two(E_AND, $1, $3); }
+;
+
+/* For symbol definitions, selects, etc., where quotes are not accepted */
+nonconst_symbol: T_WORD { $$ = sym_lookup($1, 0); free($1); };
+
+symbol:	  nonconst_symbol
+	| T_WORD_QUOTE	{ $$ = sym_lookup($1, SYMBOL_CONST); free($1); }
+;
+
+/* assignment statement */
+
+assignment_stmt:  T_WORD assign_op assign_val T_EOL	{ variable_add($1, $3, $2); free($1); free($3); }
+
+assign_op:
+	  T_EQUAL	{ $$ = VAR_RECURSIVE; }
+	| T_COLON_EQUAL	{ $$ = VAR_SIMPLE; }
+	| T_PLUS_EQUAL	{ $$ = VAR_APPEND; }
+;
+
+assign_val:
+	/* empty */		{ $$ = xstrdup(""); };
+	| T_ASSIGN_VAL
+;
+
+%%
+
+/**
+ * transitional_check_sanity - check transitional symbols have no other
+ *			       properties
+ *
+ * @menu: menu of the potentially transitional symbol
+ *
+ * Return: -1 if an error is found, 0 otherwise.
+ */
+static int transitional_check_sanity(const struct menu *menu)
+{
+	struct property *prop;
+
+	if (!menu->sym || !(menu->sym->flags & SYMBOL_TRANS))
+		return 0;
+
+	/* Check for depends and visible conditions. */
+	if ((menu->dep && !expr_is_yes(menu->dep)) ||
+	    (menu->visibility && !expr_is_yes(menu->visibility))) {
+		fprintf(stderr, "%s:%d: error: %s",
+			menu->filename, menu->lineno,
+			"transitional symbols can only have help sections\n");
+		return -1;
+	}
+
+	/* Check for any property other than "help". */
+	for (prop = menu->sym->prop; prop; prop = prop->next) {
+		if (prop->type != P_COMMENT) {
+			fprintf(stderr, "%s:%d: error: %s",
+				prop->filename, prop->lineno,
+				"transitional symbols can only have help sections\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * choice_check_sanity - check sanity of a choice member
+ *
+ * @menu: menu of the choice member
+ *
+ * Return: -1 if an error is found, 0 otherwise.
+ */
+static int choice_check_sanity(const struct menu *menu)
+{
+	struct property *prop;
+	int ret = 0;
+
+	for (prop = menu->sym->prop; prop; prop = prop->next) {
+		if (prop->type == P_DEFAULT) {
+			fprintf(stderr, "%s:%d: error: %s",
+				prop->filename, prop->lineno,
+				"defaults for choice values not supported\n");
+			ret = -1;
+		}
+
+		if (prop->menu != menu && prop->type == P_PROMPT) {
+			fprintf(stderr, "%s:%d: error: %s",
+				prop->filename, prop->lineno,
+				"choice value must not have a prompt in another entry\n");
+			ret = -1;
+		}
+	}
+
+	return ret;
+}
+
+void conf_parse(const char *name)
+{
+	struct menu *menu;
+
+	autoconf_cmd = str_new();
+
+	str_printf(&autoconf_cmd, "\ndeps_config := \\\n");
+
+	zconf_initscan(name);
+
+	_menu_init();
+
+	if (getenv("ZCONF_DEBUG"))
+		yydebug = 1;
+	yyparse();
+
+	str_printf(&autoconf_cmd,
+		   "\n"
+		   "$(autoconfig): $(deps_config)\n"
+		   "$(deps_config): ;\n");
+
+	env_write_dep(&autoconf_cmd);
+
+	/* Variables are expanded in the parse phase. We can free them here. */
+	variable_all_del();
+
+	if (yynerrs)
+		exit(1);
+	if (!modules_sym)
+		modules_sym = &symbol_no;
+
+	if (!menu_has_prompt(&rootmenu)) {
+		current_entry = &rootmenu;
+		menu_add_prompt(P_MENU, "Main menu", NULL);
+	}
+
+	menu_finalize();
+
+	menu_for_each_entry(menu) {
+		struct menu *child;
+
+		if (menu->sym && sym_check_deps(menu->sym))
+			yynerrs++;
+
+		if (transitional_check_sanity(menu))
+			yynerrs++;
+
+		if (menu->sym && sym_is_choice(menu->sym)) {
+			menu_for_each_sub_entry(child, menu)
+				if (child->sym && choice_check_sanity(child))
+					yynerrs++;
+		}
+	}
+
+	if (yynerrs)
+		exit(1);
+	conf_set_changed(true);
+}
+
+static bool zconf_endtoken(const char *tokenname,
+			   const char *expected_tokenname)
+{
+	if (strcmp(tokenname, expected_tokenname)) {
+		zconf_error("unexpected '%s' within %s block",
+			    tokenname, expected_tokenname);
+		yynerrs++;
+		return false;
+	}
+	if (strcmp(current_menu->filename, cur_filename)) {
+		zconf_error("'%s' in different file than '%s'",
+			    tokenname, expected_tokenname);
+		fprintf(stderr, "%s:%d: location of the '%s'\n",
+			current_menu->filename, current_menu->lineno,
+			expected_tokenname);
+		yynerrs++;
+		return false;
+	}
+	return true;
+}
+
+static void zconf_error(const char *err, ...)
+{
+	va_list ap;
+
+	yynerrs++;
+	fprintf(stderr, "%s:%d: ", cur_filename, cur_lineno);
+	va_start(ap, err);
+	vfprintf(stderr, err, ap);
+	va_end(ap);
+	fprintf(stderr, "\n");
+}
+
+static void yyerror(const char *err)
+{
+	fprintf(stderr, "%s:%d: %s\n", cur_filename, cur_lineno, err);
+}
+
+static void print_quoted_string(FILE *out, const char *str)
+{
+	const char *p;
+	int len;
+
+	putc('"', out);
+	while ((p = strchr(str, '"'))) {
+		len = p - str;
+		if (len)
+			fprintf(out, "%.*s", len, str);
+		fputs("\\\"", out);
+		str = p + 1;
+	}
+	fputs(str, out);
+	putc('"', out);
+}
+
+static void print_symbol(FILE *out, const struct menu *menu)
+{
+	struct symbol *sym = menu->sym;
+	struct property *prop;
+
+	if (sym_is_choice(sym))
+		fprintf(out, "\nchoice\n");
+	else
+		fprintf(out, "\nconfig %s\n", sym->name);
+	switch (sym->type) {
+	case S_BOOLEAN:
+		fputs("  bool\n", out);
+		break;
+	case S_TRISTATE:
+		fputs("  tristate\n", out);
+		break;
+	case S_STRING:
+		fputs("  string\n", out);
+		break;
+	case S_INT:
+		fputs("  integer\n", out);
+		break;
+	case S_HEX:
+		fputs("  hex\n", out);
+		break;
+	default:
+		fputs("  ???\n", out);
+		break;
+	}
+	for (prop = sym->prop; prop; prop = prop->next) {
+		if (prop->menu != menu)
+			continue;
+		switch (prop->type) {
+		case P_PROMPT:
+			fputs("  prompt ", out);
+			print_quoted_string(out, prop->text);
+			if (!expr_is_yes(prop->visible.expr)) {
+				fputs(" if ", out);
+				expr_fprint(prop->visible.expr, out);
+			}
+			fputc('\n', out);
+			break;
+		case P_DEFAULT:
+			fputs( "  default ", out);
+			expr_fprint(prop->expr, out);
+			if (!expr_is_yes(prop->visible.expr)) {
+				fputs(" if ", out);
+				expr_fprint(prop->visible.expr, out);
+			}
+			fputc('\n', out);
+			break;
+		case P_SELECT:
+			fputs( "  select ", out);
+			expr_fprint(prop->expr, out);
+			fputc('\n', out);
+			break;
+		case P_IMPLY:
+			fputs( "  imply ", out);
+			expr_fprint(prop->expr, out);
+			fputc('\n', out);
+			break;
+		case P_RANGE:
+			fputs( "  range ", out);
+			expr_fprint(prop->expr, out);
+			fputc('\n', out);
+			break;
+		case P_MENU:
+			fputs( "  menu ", out);
+			print_quoted_string(out, prop->text);
+			fputc('\n', out);
+			break;
+		default:
+			fprintf(out, "  unknown prop %d!\n", prop->type);
+			break;
+		}
+	}
+	if (menu->help) {
+		int len = strlen(menu->help);
+		while (menu->help[--len] == '\n')
+			menu->help[len] = 0;
+		fprintf(out, "  help\n%s\n", menu->help);
+	}
+}
+
+void zconfdump(FILE *out)
+{
+	struct property *prop;
+	struct symbol *sym;
+	struct menu *menu;
+
+	menu = rootmenu.list;
+	while (menu) {
+		if ((sym = menu->sym))
+			print_symbol(out, menu);
+		else if ((prop = menu->prompt)) {
+			switch (prop->type) {
+			case P_COMMENT:
+				fputs("\ncomment ", out);
+				print_quoted_string(out, prop->text);
+				fputs("\n", out);
+				break;
+			case P_MENU:
+				fputs("\nmenu ", out);
+				print_quoted_string(out, prop->text);
+				fputs("\n", out);
+				break;
+			default:
+				;
+			}
+			if (!expr_is_yes(prop->visible.expr)) {
+				fputs("  depends ", out);
+				expr_fprint(prop->visible.expr, out);
+				fputc('\n', out);
+			}
+		}
+
+		if (menu->list)
+			menu = menu->list;
+		else if (menu->next)
+			menu = menu->next;
+		else while ((menu = menu->parent)) {
+			if (menu->prompt && menu->prompt->type == P_MENU)
+				fputs("\nendmenu\n", out);
+			if (menu->next) {
+				menu = menu->next;
+				break;
+			}
+		}
+	}
+}