Re: [PATCH v3] mm/kasan: dump alloc and free stack for page allocator

Walter Wu
2019-09-12T14:08:38Z

> extern void __reset_page_owner(struct page *page, unsigned int order);
> diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
> index 6c9682ce0254..dc560c7562e8 100644
> --- a/lib/Kconfig.kasan
> +++ b/lib/Kconfig.kasan
> @@ -41,6 +41,8 @@ config KASAN_GENERIC
> select SLUB_DEBUG if SLUB
> select CONSTRUCTORS
> select STACKDEPOT
> + select PAGE_OWNER
> + select PAGE_OWNER_FREE_STACK
> help
> Enables generic KASAN mode.
> Supported in both GCC and Clang. With GCC it requires version 4.9.2
> @@ -63,6 +65,8 @@ config KASAN_SW_TAGS
> select SLUB_DEBUG if SLUB
> select CONSTRUCTORS
> select STACKDEPOT
> + select PAGE_OWNER
> + select PAGE_OWNER_FREE_STACK
> help

What is the difference between PAGE_OWNER+PAGE_OWNER_FREE_STACK and
DEBUG_PAGEALLOC?
If you directly enable PAGE_OWNER+PAGE_OWNER_FREE_STACK
PAGE_OWNER_FREE_STACK,don't you think low-memory device to want to use
KASAN?