Re: [PATCH v12 09/22] x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory

[Peter Zijlstra]

On Tue, Jun 27, 2023 at 02:12:39AM +1200, Kai Huang wrote:

> +static int tdx_memory_notifier(struct notifier_block *nb, unsigned long action,
> +			       void *v)
> +{
> +	struct memory_notify *mn = v;
> +
> +	if (action != MEM_GOING_ONLINE)
> +		return NOTIFY_OK;

So offlining TDX memory is ok?

> +
> +	/*
> +	 * Empty list means TDX isn't enabled.  Allow any memory
> +	 * to go online.
> +	 */
> +	if (list_empty(&tdx_memlist))
> +		return NOTIFY_OK;
> +
> +	/*
> +	 * The TDX memory configuration is static and can not be
> +	 * changed.  Reject onlining any memory which is outside of
> +	 * the static configuration whether it supports TDX or not.
> +	 */
> +	return is_tdx_memory(mn->start_pfn, mn->start_pfn + mn->nr_pages) ?
> +		NOTIFY_OK : NOTIFY_BAD;

	if (is_tdx_memory(...))
		return NOTIFY_OK;

	return NOTIFY_BAD;

> +}