Re: [PATCH v2 1/4] mm: kmemleak: add OBJECT_PHYS flag for objects allocated with physical address

From: Catalin Marinas
Date: Mon Jun 06 2022 - 07:55:51 EST


On Fri, Jun 03, 2022 at 11:54:12AM +0800, Patrick Wang wrote:
> diff --git a/mm/kmemleak.c b/mm/kmemleak.c
> index a182f5ddaf68..1e9e0aa93ae5 100644
> --- a/mm/kmemleak.c
> +++ b/mm/kmemleak.c
> @@ -172,6 +172,8 @@ struct kmemleak_object {
> #define OBJECT_NO_SCAN (1 << 2)
> /* flag set to fully scan the object when scan_area allocation failed */
> #define OBJECT_FULL_SCAN (1 << 3)
> +/* flag set for object allocated with physical address */
> +#define OBJECT_PHYS (1 << 4)
>
> #define HEX_PREFIX " "
> /* number of bytes to print per line; must be 16 or 32 */
> @@ -575,7 +577,8 @@ static int __save_stack_trace(unsigned long *trace)
> * memory block and add it to the object_list and object_tree_root.
> */
> static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
> - int min_count, gfp_t gfp)
> + int min_count, gfp_t gfp,
> + bool is_phys)

The patch looks fine but I wonder whether we should have different
functions for is_phys true/false, we may end up fewer changes overall
since most places simply pass is_phys == false:

static struct kmemleak_object *__create_object(unsigned long ptr, size_t size,
int min_count, gfp_t gfp,
bool is_phys);

static struct kmemleak_object *create_object(unsigned long ptr, size_t size,
int min_count, gfp_t gfp)
{
return __create_object(ptr, size, min_count, gfp, false);
}

static struct kmemleak_object *create_object_phys(unsigned long ptr, size_t size,
int min_count, gfp_t gfp)
{
return __create_object(ptr, size, min_count, gfp, true);
}

Same for the other patches that change a few more functions.

--
Catalin