Commit 07313a2b authored Jun 28, 2022 by Yee Lee Committed by Andrew Morton Jul 18, 2022

mm: kfence: apply kmemleak_ignore_phys on early allocated pool

This patch solves two issues.

(1) The pool allocated by memblock needs to unregister from
kmemleak scanning. Apply kmemleak_ignore_phys to replace the
original kmemleak_free as its address now is stored in the phys tree.

(2) The pool late allocated by page-alloc doesn't need to unregister.
Move out the freeing operation from its call path.

Link: https://lkml.kernel.org/r/20220628113714.7792-2-yee.lee@mediatek.com


Fixes: 0c24e061 ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Yee Lee <yee.lee@mediatek.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

parent 14c99d65

mm/kfence/core.c

+9 −9

Original line number	Diff line number	Diff line
		@@ -603,14 +603,6 @@ static unsigned long kfence_init_pool(void)
		addr += 2 * PAGE_SIZE;
		}

		/*
		* The pool is live and will never be deallocated from this point on.
		* Remove the pool object from the kmemleak object tree, as it would
		* otherwise overlap with allocations returned by kfence_alloc(), which
		* are registered with kmemleak through the slab post-alloc hook.
		*/
		kmemleak_free(__kfence_pool);

		return 0;
		}

		@@ -623,8 +615,16 @@ static bool __init kfence_init_pool_early(void)

		addr = kfence_init_pool();

		if (!addr)
		if (!addr) {
		/*
		* The pool is live and will never be deallocated from this point on.
		* Ignore the pool object from the kmemleak phys object tree, as it would
		* otherwise overlap with allocations returned by kfence_alloc(), which
		* are registered with kmemleak through the slab post-alloc hook.
		*/
		kmemleak_ignore_phys(__pa(__kfence_pool));
		return true;
		}

		/*
		* Only release unprotected pages, and do not try to go back and change