Re: [PATCH v2 3/5] x86/virt/tdx: Add SEAMCALL wrapper for TDH.SYS.DISABLE

From: Kiryl Shutsemau

Date: Tue Mar 31 2026 - 08:18:54 EST


On Mon, Mar 30, 2026 at 07:25:22PM +0000, Edgecombe, Rick P wrote:
> > I assumed that if the SEAMCALL fails other SEAMCALLs suppose to be
> > functional. Hm?
>
> The behavior should be that once you make this seamcall (assuming it's
> supported) that no other seamcalls can be made. They will return an
> error. Do you think something else would be better? If it's an old TDX
> module, nothing happens of course.

I guess the actual behaviour is dependant on the return code. It is
obviously going to be the case for TDX_SUCCESS. And from the discussion,
I guess that's true for TDX_SYS_BUSY and TDX_INTERRUPTED_RESUMABLE.

What about other cases? The spec draft also lists TDX_SYS_NOT_READY and
TDX_SYS_SHUTDOWN.

I wounder if it can affect the kernel. Consider the case when kexec
(crash kernel start) happens due to crash on TDX module.

Will we be able to shutdown TDX module cleanly and make kexec safe?

--
Kiryl Shutsemau / Kirill A. Shutemov