From fed84c78527009d4f799a3ed9a566502fa026d82 Mon Sep 17 00:00:00 2001 From: Qian Cai Date: Fri, 28 Dec 2018 00:36:29 -0800 Subject: mm/memblock.c: skip kmemleak for kasan_init() Kmemleak does not play well with KASAN (tested on both HPE Apollo 70 and Huawei TaiShan 2280 aarch64 servers). After calling start_kernel()->setup_arch()->kasan_init(), kmemleak early log buffer went from something like 280 to 260000 which caused kmemleak disabled and crash dump memory reservation failed. The multitude of kmemleak_alloc() calls is from nested loops while KASAN is setting up full memory mappings, so let early kmemleak allocations skip those memblock_alloc_internal() calls came from kasan_init() given that those early KASAN memory mappings should not reference to other memory. Hence, no kmemleak false positives. kasan_init kasan_map_populate [1] kasan_pgd_populate [2] kasan_pud_populate [3] kasan_pmd_populate [4] kasan_pte_populate [5] kasan_alloc_zeroed_page memblock_alloc_try_nid memblock_alloc_internal kmemleak_alloc [1] for_each_memblock(memory, reg) [2] while (pgdp++, addr = next, addr != end) [3] while (pudp++, addr = next, addr != end && pud_none(READ_ONCE(*pudp))) [4] while (pmdp++, addr = next, addr != end && pmd_none(READ_ONCE(*pmdp))) [5] while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep))) Link: http://lkml.kernel.org/r/1543442925-17794-1-git-send-email-cai@gmx.us Signed-off-by: Qian Cai Acked-by: Catalin Marinas Cc: Michal Hocko Cc: Mike Rapoport Cc: Alexander Potapenko Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memblock.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'mm/memblock.c') diff --git a/mm/memblock.c b/mm/memblock.c index f57d7620668b..022d4cbb3618 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -262,7 +262,8 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size, phys_addr_t kernel_end, ret; /* pump up @end */ - if (end == MEMBLOCK_ALLOC_ACCESSIBLE) + if (end == MEMBLOCK_ALLOC_ACCESSIBLE || + end == MEMBLOCK_ALLOC_KASAN) end = memblock.current_limit; /* avoid allocating the first page */ @@ -1419,13 +1420,15 @@ again: done: ptr = phys_to_virt(alloc); - /* - * The min_count is set to 0 so that bootmem allocated blocks - * are never reported as leaks. This is because many of these blocks - * are only referred via the physical address which is not - * looked up by kmemleak. - */ - kmemleak_alloc(ptr, size, 0, 0); + /* Skip kmemleak for kasan_init() due to high volume. */ + if (max_addr != MEMBLOCK_ALLOC_KASAN) + /* + * The min_count is set to 0 so that bootmem allocated + * blocks are never reported as leaks. This is because many + * of these blocks are only referred via the physical + * address which is not looked up by kmemleak. + */ + kmemleak_alloc(ptr, size, 0, 0); return ptr; } -- cgit v1.2.3-59-g8ed1b