Commit 67a454e6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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
parents bbbf7f32 83c8f7b5

Documentation/admin-guide/kernel-parameters.txt

+8 −0
Original line number Diff line number Diff line
@@ -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

+9 −1
Original line number Diff line number Diff line
@@ -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

	/*