From b2aad24b53333f1904a55d97e3fde2246ef05bb6 Mon Sep 17 00:00:00 2001 From: Guo Weikang Date: Mon, 6 Jan 2025 10:11:25 +0800 Subject: mm/memmap: prevent double scanning of memmap by kmemleak kmemleak explicitly scans the mem_map through the valid struct page objects. However, memmap_alloc() was also adding this memory to the gray object list, causing it to be scanned twice. Remove memmap_alloc() from the scan list and add a comment to clarify the behavior. Link: https://lore.kernel.org/lkml/CAOm6qn=FVeTpH54wGDFMHuCOeYtvoTx30ktnv9-w3Nh8RMofEA@mail.gmail.com/ Link: https://lkml.kernel.org/r/20250106021126.1678334-1-guoweikang.kernel@gmail.com Signed-off-by: Guo Weikang Reviewed-by: Catalin Marinas Cc: Mike Rapoport (Microsoft) Signed-off-by: Andrew Morton --- mm/mm_init.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'mm/mm_init.c') diff --git a/mm/mm_init.c b/mm/mm_init.c index 24b68b425afb..2630cc30147e 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1585,13 +1585,17 @@ void __init *memmap_alloc(phys_addr_t size, phys_addr_t align, { void *ptr; + /* + * Kmemleak will explicitly scan mem_map by traversing all valid + * `struct *page`,so memblock does not need to be added to the scan list. + */ if (exact_nid) ptr = memblock_alloc_exact_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, + MEMBLOCK_ALLOC_NOLEAKTRACE, nid); else ptr = memblock_alloc_try_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, + MEMBLOCK_ALLOC_NOLEAKTRACE, nid); if (ptr && size > 0) -- cgit v1.2.3