Re: [PATCH v4 1/7] kernel/fork: convert vma assignment to a memcpy

From: Mike Rapoport
Date: Thu Jan 26 2023 - 14:41:48 EST


On Thu, Jan 26, 2023 at 11:37:46AM -0800, Suren Baghdasaryan 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.
>
> Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>

Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>

> ---
> kernel/fork.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/fork.c b/kernel/fork.c
> index 441dcec60aae..9260f975b8f4 100644
> --- a/kernel/fork.c
> +++ b/kernel/fork.c
> @@ -472,7 +472,7 @@ 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);
> + data_race(memcpy(new, orig, sizeof(*new)));
> INIT_LIST_HEAD(&new->anon_vma_chain);
> dup_anon_vma_name(orig, new);
> }
> --
> 2.39.1
>

--
Sincerely yours,
Mike.