RE: [RFC PATCH 05/15] virt: tdx-guest: Add TDCM helpers and TEE-IO support check

[Duan, Zhenzhong]

>-----Original Message-----
>From: Nikolay Borisov <nik.borisov@xxxxxxxx>
>Subject: Re: [RFC PATCH 05/15] virt: tdx-guest: Add TDCM helpers and TEE-IO
>support check
>
>
>
>On 26.10.26 г. 3:26 ч., Xiaoyao Li wrote:
>> On 10/14/2026 2:11 PM, Duan, Zhenzhong wrote:
>>>> This is used to allow TD guest TEE-IO Device Control and Management
>>>> (TDCM) module to
>>>> manage the device. The TDCM leaf functions are defined in the following
>>>> table
>>>>
>>>> Is TDCM module implemented via the NRX facility ?  The TDX Connect spec
>>>> never mentions the TDCM module. A bit more details are required in
>order
>>>> to better understand why you've implemented this the way you have.
>>> "TDCM module" is GHCI terminology. In this series, the guest-side
>>> implementation is in the TDX TSM driver; it is not an NRX module.
>>
>> I think the TDX guest TSM driver is just the implementation of the "TDCM
>module"
>> called in GHCI, right?
>
>I think we are entering a dangerous bikeshedding territory here. But
>IIUC TDCM seems to be something which the TD calls, because it sends the
>TDCM function ids to the host, so the TDCM should really be implemented
>by the host. But I think such construct just adds more confusion, TDCM
>is just a subset of the GHCI, so nothing really more special.

GHCI spec says:

"This is used to allow TD guest TEE-IO Device Control and Management (TDCM) module to 
manage the device."

So I think "TDCM module" term in GHCI spec is talking about guest side - the TDX TSM driver.

Since "TDCM module" term is confusing for reader, so I plan to drop it
in next version, I plan to use "TDCM request" to denote the guest-side
operations and "TDCM implementation" to denote the host-side logic.
let me know if this distinction makes sense to you all, or if you have
any other suggestions.