Message-ID: <31e7d93d-0e0f-4976-bff6-84f484a8a6f3@amazon.com>
Date: Fri, 16 Jan 2026 17:32:35 +0000
From: Nikita Kalyazin <kalyazin@...zon.com>
To: Sean Christopherson <seanjc@...gle.com>, Rick P Edgecombe
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Subject: Re: [PATCH v9 07/13] KVM: guest_memfd: Add flag to remove from direct
 map



On 16/01/2026 15:41, Sean Christopherson wrote:
> On Fri, Jan 16, 2026, Rick P Edgecombe wrote:
>> On Fri, 2026-01-16 at 15:02 +0000, Nikita Kalyazin wrote:
>>>> TDX does some clearing at the direct map mapping for pages that
>>>> comes from gmem, using a special instruction. It also does some
>>>> clflushing at the direct map address for these pages. So I think we
>>>> need to make sure TDs don't pull from gmem fds with this flag.
>>>
>>> Would you be able to give a pointer on how we can do that?  I'm not
>>> very familiar with the TDX code.
>>
>> Uhh, that is a good question. Let me think.
> 
> Pass @kvm to kvm_arch_gmem_supports_no_direct_map() and then return %false if
> it's a TDX VM.

Sounds good to me, thanks.

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