Re: [PATCH 1/9] mm: kmemleak: properly disable task stack scanning

[Catalin Marinas]

On Mon, Jan 23, 2023 at 11:04:11AM -0600, George Prekas wrote:
> @@ -1586,23 +1608,6 @@ static void kmemleak_scan(void)
>  	}
>  	put_online_mems();
>  
> -	/*
> -	 * Scanning the task stacks (may introduce false negatives).
> -	 */
> -	if (kmemleak_stack_scan) {
> -		struct task_struct *p, *g;
> -
> -		rcu_read_lock();
> -		for_each_process_thread(g, p) {
> -			void *stack = try_get_task_stack(p);
> -			if (stack) {
> -				scan_block(stack, stack + THREAD_SIZE, NULL);
> -				put_task_stack(p);
> -			}
> -		}
> -		rcu_read_unlock();
> -	}

On architectures without VMAP_STACK, we still need the above otherwise
it could lead to some false positives.

-- 
Catalin