Date:   Thu, 26 Jan 2023 21:40:41 +0200
From:   Mike Rapoport <rppt@kernel.org>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     akpm@linux-foundation.org, michel@lespinasse.org,
        jglisse@google.com, mhocko@suse.com, vbabka@suse.cz,
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Subject: Re: [PATCH v4 1/7] kernel/fork: convert vma assignment to a memcpy
Message-ID: <Y9LXOUMTY4hW3+SQ@kernel.org>
References: <20230126193752.297968-1-surenb@google.com>
 <20230126193752.297968-2-surenb@google.com>
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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@google.com>
> Acked-by: Mel Gorman <mgorman@techsingularity.net>

Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>

> ---
>  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.