Merge tag 'v6.5-rc1-sysctl-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull sysctl updates from Luis Chamberlain:
 "The changes for sysctl are in line with prior efforts to stop usage of
  deprecated routines which incur recursion and also make it hard to
  remove the empty array element in each sysctl array declaration.

  The most difficult user to modify was parport which required a bit of
  re-thinking of how to declare shared sysctls there, Joel Granados has
  stepped up to the plate to do most of this work and eventual removal
  of register_sysctl_table(). That work ended up saving us about 1465
  bytes according to bloat-o-meter. Since we gained a few bloat-o-meter
  karma points I moved two rather small sysctl arrays from
  kernel/sysctl.c leaving us only two more sysctl arrays to move left.

  Most changes have been tested on linux-next for about a month. The
  last straggler patches are a minor parport fix, changes to the sysctl
  kernel selftest so to verify correctness and prevent regressions for
  the future change he made to provide an alternative solution for the
  special sysctl mount point target which was using the now deprecated
  sysctl child element.

  This is all prep work to now finally be able to remove the empty array
  element in all sysctl declarations / registrations which is expected
  to save us a bit of bytes all over the kernel. That work will be
  tested early after v6.5-rc1 is out"

* tag 'v6.5-rc1-sysctl-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  sysctl: replace child with an enumeration
  sysctl: Remove debugging dump_stack
  test_sysclt: Test for registering a mount point
  test_sysctl: Add an option to prevent test skip
  test_sysctl: Add an unregister sysctl test
  test_sysctl: Group node sysctl test under one func
  test_sysctl: Fix test metadata getters
  parport: plug a sysctl register leak
  sysctl: move security keys sysctl registration to its own file
  sysctl: move umh sysctl registration to its own file
  signal: move show_unhandled_signals sysctl to its own file
  sysctl: remove empty dev table
  sysctl: Remove register_sysctl_table
  sysctl: Refactor base paths registrations
  sysctl: stop exporting register_sysctl_table
  parport: Removed sysctl related defines
  parport: Remove register_sysctl_table from parport_default_proc_register
  parport: Remove register_sysctl_table from parport_device_proc_register
  parport: Remove register_sysctl_table from parport_proc_register
  parport: Move magic number "15" to a define

lib/test_sysctl.c

@@ -30,6 +30,13 @@ static int i_zero;
 static int i_one_hundred = 100;
 static int match_int_ok = 1;
 
+
+static struct {
+	struct ctl_table_header *test_h_setup_node;
+	struct ctl_table_header *test_h_mnt;
+	struct ctl_table_header *test_h_mnterror;
+} sysctl_test_headers;
+
 struct test_sysctl_data {
 	int int_0001;
 	int int_0002;
@@ -126,9 +133,7 @@ static struct ctl_table test_table[] = {
 	{ }
 };
 
-static struct ctl_table_header *test_sysctl_header;
-
-static int __init test_sysctl_init(void)
+static void test_sysctl_calc_match_int_ok(void)
 {
 	int i;
 
@@ -153,24 +158,96 @@ static int __init test_sysctl_init(void)
 	for (i = 0; i < ARRAY_SIZE(match_int); i++)
 		if (match_int[i].defined != match_int[i].wanted)
 			match_int_ok = 0;
+}
 
+static int test_sysctl_setup_node_tests(void)
+{
+	test_sysctl_calc_match_int_ok();
 	test_data.bitmap_0001 = kzalloc(SYSCTL_TEST_BITMAP_SIZE/8, GFP_KERNEL);
 	if (!test_data.bitmap_0001)
 		return -ENOMEM;
-	test_sysctl_header = register_sysctl("debug/test_sysctl", test_table);
-	if (!test_sysctl_header) {
+	sysctl_test_headers.test_h_setup_node = register_sysctl("debug/test_sysctl", test_table);
+	if (!sysctl_test_headers.test_h_setup_node) {
 		kfree(test_data.bitmap_0001);
 		return -ENOMEM;
 	}
+
 	return 0;
 }
+
+/* Used to test that unregister actually removes the directory */
+static struct ctl_table test_table_unregister[] = {
+	{
+		.procname	= "unregister_error",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+	},
+	{}
+};
+
+static int test_sysctl_run_unregister_nested(void)
+{
+	struct ctl_table_header *unregister;
+
+	unregister = register_sysctl("debug/test_sysctl/unregister_error",
+				   test_table_unregister);
+	if (!unregister)
+		return -ENOMEM;
+
+	unregister_sysctl_table(unregister);
+	return 0;
+}
+
+static int test_sysctl_run_register_mount_point(void)
+{
+	sysctl_test_headers.test_h_mnt
+		= register_sysctl_mount_point("debug/test_sysctl/mnt");
+	if (!sysctl_test_headers.test_h_mnt)
+		return -ENOMEM;
+
+	sysctl_test_headers.test_h_mnterror
+		= register_sysctl("debug/test_sysctl/mnt/mnt_error",
+				  test_table_unregister);
+	/*
+	 * Don't check the result.:
+	 * If it fails (expected behavior), return 0.
+	 * If successful (missbehavior of register mount point), we want to see
+	 * mnt_error when we run the sysctl test script
+	 */
+
+	return 0;
+}
+
+static int __init test_sysctl_init(void)
+{
+	int err;
+
+	err = test_sysctl_setup_node_tests();
+	if (err)
+		goto out;
+
+	err = test_sysctl_run_unregister_nested();
+	if (err)
+		goto out;
+
+	err = test_sysctl_run_register_mount_point();
+
+out:
+	return err;
+}
 module_init(test_sysctl_init);
 
 static void __exit test_sysctl_exit(void)
 {
 	kfree(test_data.bitmap_0001);
-	if (test_sysctl_header)
-		unregister_sysctl_table(test_sysctl_header);
+	if (sysctl_test_headers.test_h_setup_node)
+		unregister_sysctl_table(sysctl_test_headers.test_h_setup_node);
+	if (sysctl_test_headers.test_h_mnt)
+		unregister_sysctl_table(sysctl_test_headers.test_h_mnt);
+	if (sysctl_test_headers.test_h_mnterror)
+		unregister_sysctl_table(sysctl_test_headers.test_h_mnterror);
 }
 
 module_exit(test_sysctl_exit);