Re: [PATCH v3 1/7] kernel/fork: convert vma assignment to a memcpy

[Andrew Morton]

On Wed, 25 Jan 2023 15:35:48 -0800 Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote:

> Convert vma assignment in vm_area_dup() to a memcpy() to prevent compiler
> errors when we add a const modifier to vma->vm_flags.
> 
> ...
>
> --- a/kernel/fork.c
> +++ b/kernel/fork.c
> @@ -482,7 +482,7 @@ struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig)
>  		 * orig->shared.rb may be modified concurrently, but the clone
>  		 * will be reinitialized.
>  		 */
> -		*new = data_race(*orig);
> +		memcpy(new, orig, sizeof(*new));

The data_race() removal is unchangelogged?

>  		INIT_LIST_HEAD(&new->anon_vma_chain);
>  		dup_anon_vma_name(orig, new);
>  	}