Re: [PATCH v19 007/130] x86/virt/tdx: Export SEAMCALL functions

From: Huang, Kai
Date: Thu Mar 14 2024 - 20:02:36 EST




On 26/02/2024 9:25 pm, isaku.yamahata@xxxxxxxxx wrote:
From: Kai Huang <kai.huang@xxxxxxxxx>

KVM will need to make SEAMCALLs to create and run TDX guests. Export
SEAMCALL functions for KVM to use.


Could you also list the reason that we want to expose __seamcall() directly, rather than wanting to put some higher level wrappers in the TDX host code, and export them?

For example, we can give a summary of the SEAMCALLs (e.g., how many in total, and roughly introduce them based on categories) that will be used by KVM, and clarify the reasons why we want to just export __seamcall().

E.g., we can say something like this:

TD;LR:

KVM roughly will need to use dozens of SEAMCALLs, and all these are logically related to creating and running TDX guests. It makes more sense to just export __seamcall() and let KVM maintain these VM-related wrappers rather than having the TDX host code to provide wrappers for each SEAMCALL or higher-level abstraction.

Long version:

You give a detailed explanation of SEAMCALLs that will be used by KVM, and clarify logically it's better to manage these code in KVM.