linux-kernel - Re: [RFC PATCH 3/4] KVM: TDX: Exit to userspace for GetTdVmCallInfo

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <991293852693a4edf434d89c8c6c74ab93b0a0bb.camel@intel.com>
Date: Fri, 20 Jun 2025 18:27:20 +0000
From: "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To: "seanjc@...gle.com" <seanjc@...gle.com>
CC: "mikko.ylinen@...ux.intel.com" <mikko.ylinen@...ux.intel.com>, "Huang,
 Kai" <kai.huang@...el.com>, "binbin.wu@...ux.intel.com"
	<binbin.wu@...ux.intel.com>, "Yao, Jiewen" <jiewen.yao@...el.com>, "Lindgren,
 Tony" <tony.lindgren@...el.com>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "Hunter, Adrian" <adrian.hunter@...el.com>,
	"Li, Xiaoyao" <xiaoyao.li@...el.com>, "kvm@...r.kernel.org"
	<kvm@...r.kernel.org>, "Zhao, Yan Y" <yan.y.zhao@...el.com>, "Chatre,
 Reinette" <reinette.chatre@...el.com>, "Yamahata, Isaku"
	<isaku.yamahata@...el.com>, "Shutemov, Kirill" <kirill.shutemov@...el.com>,
	"pbonzini@...hat.com" <pbonzini@...hat.com>
Subject: Re: [RFC PATCH 3/4] KVM: TDX: Exit to userspace for GetTdVmCallInfo

On Wed, 2025-06-11 at 11:13 -0700, Sean Christopherson wrote:
> On Wed, Jun 11, 2025, Rick P Edgecombe wrote:
> > On Wed, 2025-06-11 at 09:26 -0700, Sean Christopherson wrote:
> > > > GetQuote is not part of the "Base" TDVMCALLs and so has a bit in
> > > > GetTdVmCallInfo. We could move it to base?
> > > 
> > > Is GetQuote actually optional?  TDX without attestation seems rather
> > > pointless.
> > 
> > I don't know if that was a consideration for why it got added to the optional
> > category. The inputs were gathered from more than just Linux.
> 
> If there's an actual use case for TDX without attestation, then by all means,
> make it optional.  I'm genuinely curious if there's a hypervisor that plans on
> productizing TDX without supporting attestation.  It's entirely possible (likely?)
> I'm missing or forgetting something.

It turns out there is a VMM that has a proprietary interface that they use
instead of GetQuote.