Re: [PATCH v6 03/11] mm, x86: Add support for eXclusive Page Frame Ownership (XPFO)

[Laura Abbott]

On 09/07/2017 10:36 AM, Tycho Andersen wrote:
> +static inline struct xpfo *lookup_xpfo(struct page *page)
> +{
> +	struct page_ext *page_ext = lookup_page_ext(page);
> +
> +	if (unlikely(!page_ext)) {
> +		WARN(1, "xpfo: failed to get page ext");
> +		return NULL;
> +	}
> +
> +	return (void *)page_ext + page_xpfo_ops.offset;
> +}
> +

Just drop the WARN. On my arm64 UEFI machine this spews warnings
under most normal operation. This should be normal for some
situations but I haven't had the time to dig into why this
is so pronounced on arm64.

Thanks,
Laura