linux-kernel - Re: [RFC PATCH 02/21] x86/virt/tdx: Enhance tdh_mem_page

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Message-ID: <aFkfL00NTlI9IBC6@yzhao56-desk.sh.intel.com>
Date: Mon, 23 Jun 2025 17:32:31 +0800
From: Yan Zhao <yan.y.zhao@...el.com>
To: Nikolay Borisov <nik.borisov@...e.com>
CC: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>, "pbonzini@...hat.com"
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Subject: Re: [RFC PATCH 02/21] x86/virt/tdx: Enhance tdh_mem_page_aug() to
 support huge pages

On Thu, Jun 19, 2025 at 12:26:07PM +0300, Nikolay Borisov wrote:
> > What about Binbin's proposal [1]? i.e.,
> > 
> > while (nr_pages)
> >       tdx_clflush_page(nth_page(page, --nr_pages));
> 
> What's the problem with using:
> 
> +       for (int i = 0; nr_pages; nr_pages--)
> +               tdx_clflush_page(nth_page(page, i++))
Thanks! It looks good to me.

> The kernel now allows C99-style definition of variables inside a loop + it's
> clear how many times the loop has to be executed.