Re: [PATCH mm-unstable v1 1/4] mm/swap: stop using page->private on tail pages for THP_SWAP

From: Catalin Marinas <catalin.marinas@arm.com>
To: David Hildenbrand <david@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	linux-arm-kernel@lists.infradead.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Matthew Wilcox <willy@infradead.org>,
	Peter Xu <peterx@redhat.com>, Will Deacon <will@kernel.org>,
	Hugh Dickins <hughd@google.com>,
	Seth Jennings <sjenning@redhat.com>,
	Dan Streetman <ddstreet@ieee.org>,
	Vitaly Wool <vitaly.wool@konsulko.com>
Subject: Re: [PATCH mm-unstable v1 1/4] mm/swap: stop using page->private on tail pages for THP_SWAP
Date: Tue, 22 Aug 2023 17:24:18 +0100	[thread overview]
Message-ID: <ZOThMse/o7WtOkOH@arm.com> (raw)
In-Reply-To: <20230821160849.531668-2-david@redhat.com>

On Mon, Aug 21, 2023 at 06:08:46PM +0200, David Hildenbrand wrote:
> diff --git a/arch/arm64/mm/mteswap.c b/arch/arm64/mm/mteswap.c
> index cd508ba80ab1..a31833e3ddc5 100644
> --- a/arch/arm64/mm/mteswap.c
> +++ b/arch/arm64/mm/mteswap.c
> @@ -33,8 +33,9 @@ int mte_save_tags(struct page *page)
>  
>  	mte_save_page_tags(page_address(page), tag_storage);
>  
> -	/* page_private contains the swap entry.val set in do_swap_page */
> -	ret = xa_store(&mte_pages, page_private(page), tag_storage, GFP_KERNEL);
> +	/* lookup the swap entry.val from the page */
> +	ret = xa_store(&mte_pages, page_swap_entry(page).val, tag_storage,
> +		       GFP_KERNEL);
>  	if (WARN(xa_is_err(ret), "Failed to store MTE tags")) {
>  		mte_free_tag_storage(tag_storage);
>  		return xa_err(ret);

For arm64:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>