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Date:   Wed, 14 Jun 2023 15:31:36 +0300
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Subject: Re: [PATCH v11 11/20] x86/virt/tdx: Fill out TDMRs to cover all TDX
 memory regions
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To:     Kai Huang <kai.huang@intel.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
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On 4.06.23 г. 17:27 ч., Kai Huang wrote:
<snip>

> ---
>   arch/x86/virt/vmx/tdx/tdx.c | 94 ++++++++++++++++++++++++++++++++++++-
>   1 file changed, 93 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index 7a20c72361e7..fa9fa8bc581a 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -385,6 +385,93 @@ static void free_tdmr_list(struct tdmr_info_list *tdmr_list)
>   			tdmr_list->max_tdmrs * tdmr_list->tdmr_sz);
>   }
>   
> +/* Get the TDMR from the list at the given index. */
> +static struct tdmr_info *tdmr_entry(struct tdmr_info_list *tdmr_list,
> +				    int idx)
> +{
> +	int tdmr_info_offset = tdmr_list->tdmr_sz * idx;
> +
> +	return (void *)tdmr_list->tdmrs + tdmr_info_offset;

nit: I would just like to point that sizeof(void *) being treated as 1 
is a gcc-specific compiler extension: 
https://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Pointer-Arith.html#Pointer-Arith

I don't know if clang treats it the same way, just for the sake of 
simplicity you might wanna change this (void *) to (char *).

<snip>