Merge tag 'memblock-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

Pull memblock update from Mike Rapoport:
 "Introduce a 'check_pages' boot parameter to decouple simple checks for
  page state on allocation and free from CONFIG_DEBUG_VM.

  This allows enabling page checking without building kernel with
  CONFIG_DEBUG_VM or forcing init_on_{alloc, free} or other heavier
  mechanisms"

* tag 'memblock-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  mm/mm_init: Introduce a boot parameter for check_pages

Author: torvalds

Documentation/admin-guide/kernel-parameters.txt

@@ -767,6 +767,14 @@ Kernel parameters
 			nokmem -- Disable kernel memory accounting.
 			nobpf -- Disable BPF memory accounting.
 
+	check_pages=	[MM,EARLY] Enable sanity checking of pages after
+			allocations / before freeing. This adds checks to catch
+			double-frees, use-after-frees, and other sources of
+			page corruption by inspecting page internals (flags,
+			mapcount/refcount, memcg_data, etc.).
+			Format: { "0" | "1" }
+			Default: 0 (1 if CONFIG_DEBUG_VM is set)
+
 	checkreqprot=	[SELINUX] Set initial checkreqprot flag value.
 			Format: { "0" | "1" }
 			See security/selinux/Kconfig help text.

mm/mm_init.c

@@ -2525,6 +2525,14 @@ early_param("init_on_free", early_init_on_free);
 
 DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
 
+static bool check_pages_enabled_early __initdata;
+
+static int __init early_check_pages(char *buf)
+{
+	return kstrtobool(buf, &check_pages_enabled_early);
+}
+early_param("check_pages", early_check_pages);
+
 /*
  * Enable static keys related to various memory debugging and hardening options.
  * Some override others, and depend on early params that are evaluated in the
@@ -2534,7 +2542,7 @@ DEFINE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);
 static void __init mem_debugging_and_hardening_init(void)
 {
 	bool page_poisoning_requested = false;
-	bool want_check_pages = false;
+	bool want_check_pages = check_pages_enabled_early;
 
 #ifdef CONFIG_PAGE_POISONING
 	/*