Re: [PATCH v3 07/26] x86/virt/seamldr: Introduce a wrapper for P-SEAMLDR SEAMCALLs

[Dave Hansen]

On 1/30/26 00:08, Chao Gao wrote:
> On Wed, Jan 28, 2026 at 03:04:55PM -0800, Dave Hansen wrote:
>> On 1/23/26 06:55, Chao Gao wrote:
>>> SEAMRET from the P-SEAMLDR clears the current VMCS structure pointed 
>>> to by the current-VMCS pointer. A VMM that invokes the P-SEAMLDR
>>> using SEAMCALL must reload the current-VMCS, if required, using the
>>> VMPTRLD instruction.
>>
>> That seems pretty mean.
>>
>> This is going to need a lot more justification for why this is an
>> absolutely necessary requirement.
> 
> AFAIK, this is a CPU implementation issue. The actual requirement is to
> evict (flush and invalidate) all VMCSs __cached in SEAM mode__, but big
> cores implement this by evicting the __entire__ VMCS cache. So, the
> current VMCS is invalidated and cleared.

But why is this a P-SEAMLDR thing and not a TDX module thing?

It seems like a bug, or at least a P-SEAMLDR implementation issue the
needs to get fixed.