modules changes for v6.2-rc1

Tux gets for xmass improving the average lookup performance of
 kallsyms_lookup_name() by 715x thanks to the work by Zhen Lei, which
 upgraded our old implementation from being O(n) to O(log(n)), while also
 retaining the old implementation support on /proc/kallsyms. The only
 penalty was increasing the memory footprint by 3 * kallsyms_num_syms.
 Folks who want to improve this further now also have a dedicated selftest
 facility through KALLSYMS_SELFTEST. Since I had to start reviewing other
 future kallsyms / modules enhancements by Nick Alcock (his stuff is not
 merged, it requires more work) I carefully reviewed and merged Zhen Lei's
 kallsyms changes through modules-next tree a bit less than a month ago.
 So this has been exposed on linux-next for about a month now with no
 reported regressions.
 
 Stephen Boyd added zstd in-kernel decompression support, but the only
 users of this would be folks using the load-pin LSM because otherwise
 we do module docompression in userspace. This is the newest code and
 was merged last week on modules-next.
 
 We spent a lot of time analyzing and coming to grips with a proper
 fix to an old modules regression which only recently came to light
 (since v5.3-rc1, May 2019) but even though I merged that fix onto
 modules-next last week I'm having second thoughts about it now as I was
 writing about that fix in this git tag message for you, as I found a few
 things we cannot quite justify there yet. So I'm going to push back to the
 drawing board again there until all i's are properly dotted. Yes, it's a
 regression but the issue has been there for 2 years now and it came up
 because of high end CPU count, it can wait a *tiny* bit more for a proper
 fix.
 
 The only other thing with mentioning is a minor boot time optimization by
 Rasmus Villemoes which deferes param_sysfs_init() to late init. The rest
 is cleanups and minor fixes.
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Merge tag 'modules-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull modules updates from Luis Chamberlain:
 "Tux gets for xmas an improvement to the average lookup performance of
  kallsyms_lookup_name() by 715x thanks to the work by Zhen Lei, which
  upgraded our old implementation from being O(n) to O(log(n)), while
  also retaining the old implementation support on /proc/kallsyms.

  The only penalty was increasing the memory footprint by 3 *
  kallsyms_num_syms. Folks who want to improve this further now also
  have a dedicated selftest facility through KALLSYMS_SELFTEST.

  Stephen Boyd added zstd in-kernel decompression support, but the only
  users of this would be folks using the load-pin LSM because otherwise
  we do module decompression in userspace.

  The only other thing with mentioning is a minor boot time optimization
  by Rasmus Villemoes which deferes param_sysfs_init() to late init. The
  rest is cleanups and minor fixes"

* tag 'modules-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  livepatch: Call klp_match_callback() in klp_find_callback() to avoid code duplication
  module/decompress: Support zstd in-kernel decompression
  kallsyms: Remove unneeded semicolon
  kallsyms: Add self-test facility
  livepatch: Use kallsyms_on_each_match_symbol() to improve performance
  kallsyms: Add helper kallsyms_on_each_match_symbol()
  kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[]
  kallsyms: Correctly sequence symbols when CONFIG_LTO_CLANG=y
  kallsyms: Improve the performance of kallsyms_lookup_name()
  scripts/kallsyms: rename build_initial_tok_table()
  module: Fix NULL vs IS_ERR checking for module_get_next_page
  kernel/params.c: defer most of param_sysfs_init() to late_initcall time
  module: Remove unused macros module_addr_min/max
  module: remove redundant module_sysfs_initialized variable

kernel/livepatch/core.c

@@ -125,6 +125,24 @@ struct klp_find_arg {
 	unsigned long pos;
 };
 
+static int klp_match_callback(void *data, unsigned long addr)
+{
+	struct klp_find_arg *args = data;
+
+	args->addr = addr;
+	args->count++;
+
+	/*
+	 * Finish the search when the symbol is found for the desired position
+	 * or the position is not defined for a non-unique symbol.
+	 */
+	if ((args->pos && (args->count == args->pos)) ||
+	    (!args->pos && (args->count > 1)))
+		return 1;
+
+	return 0;
+}
+
 static int klp_find_callback(void *data, const char *name,
 			     struct module *mod, unsigned long addr)
 {
@@ -139,18 +157,7 @@ static int klp_find_callback(void *data, const char *name,
 	if (args->objname && strcmp(args->objname, mod->name))
 		return 0;
 
-	args->addr = addr;
-	args->count++;
-
-	/*
-	 * Finish the search when the symbol is found for the desired position
-	 * or the position is not defined for a non-unique symbol.
-	 */
-	if ((args->pos && (args->count == args->pos)) ||
-	    (!args->pos && (args->count > 1)))
-		return 1;
-
-	return 0;
+	return klp_match_callback(data, addr);
 }
 
 static int klp_find_object_symbol(const char *objname, const char *name,
@@ -167,7 +174,7 @@ static int klp_find_object_symbol(const char *objname, const char *name,
 	if (objname)
 		module_kallsyms_on_each_symbol(klp_find_callback, &args);
 	else
-		kallsyms_on_each_symbol(klp_find_callback, &args);
+		kallsyms_on_each_match_symbol(klp_match_callback, name, &args);
 
 	/*
 	 * Ensure an address was found. If sympos is 0, ensure symbol is unique;