Re: [PATCH v10 1/2] x86/tdx: Add TDX Guest attestation interface driver

From: Sathyanarayanan Kuppuswamy
Date: Fri Aug 05 2022 - 17:36:01 EST




On 8/5/22 12:47 PM, Wander Lairson Costa wrote:
> On Wed, Aug 03, 2022 at 05:33:22PM -0700, Kuppuswamy Sathyanarayanan wrote:
>> +/**
>> + * struct tdx_report_req: Get TDREPORT using REPORTDATA as input.
>> + *
>> + * @subtype : Subtype of TDREPORT (fixed as 0 by TDX Module
>> + * specification, but added a parameter to handle
>> + * future extension).
>> + * @reportdata : User-defined REPORTDATA to be included into
>> + * TDREPORT. Typically it can be some nonce
>> + * provided by attestation service, so the
>> + * generated TDREPORT can be uniquely verified.
>> + * @rpd_len : Length of the REPORTDATA (fixed as 64 bytes by
>> + * the TDX Module specification, but parameter is
>> + * added to handle future extension).
>> + * @tdreport : TDREPORT output from TDCALL[TDG.MR.REPORT].
>> + * @tdr_len : Length of the TDREPORT (fixed as 1024 bytes by
>> + * the TDX Module specification, but a parameter
>> + * is added to accommodate future extension).
>> + *
>> + * Used in TDX_CMD_GET_REPORT IOCTL request.
>> + */
>> +struct tdx_report_req {
>> + __u8 subtype;
>> + __u64 reportdata;
>> + __u32 rpd_len;
>> + __u64 tdreport;
>> + __u32 tdr_len;
>> +};
>
> Any reason why reportdata and tdreport aren't "void *"?

It is the recommended way to pass the pointers.

https://docs.kernel.org/driver-api/ioctl.html

>
>> +
>

--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer