linux-kernel - Re: [PATCH v8 00/30] TDX KVM selftests

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Message-ID: <aJoqqTM9zdcSx1Fi@google.com>
Date: Mon, 11 Aug 2025 10:38:49 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sagi Shahar <sagis@...gle.com>
Cc: linux-kselftest@...r.kernel.org, Paolo Bonzini <pbonzini@...hat.com>, 
	Shuah Khan <shuah@...nel.org>, Ackerley Tng <ackerleytng@...gle.com>, 
	Ryan Afranji <afranji@...gle.com>, Andrew Jones <ajones@...tanamicro.com>, 
	Isaku Yamahata <isaku.yamahata@...el.com>, Erdem Aktas <erdemaktas@...gle.com>, 
	Rick Edgecombe <rick.p.edgecombe@...el.com>, Roger Wang <runanwang@...gle.com>, 
	Binbin Wu <binbin.wu@...ux.intel.com>, Oliver Upton <oliver.upton@...ux.dev>, 
	"Pratik R. Sampat" <pratikrajesh.sampat@....com>, Reinette Chatre <reinette.chatre@...el.com>, 
	Ira Weiny <ira.weiny@...el.com>, linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [PATCH v8 00/30] TDX KVM selftests

On Thu, Aug 07, 2025, Sagi Shahar wrote:
> This is v8 of the TDX selftests.
> 
> This series is based on v6.16
> 
> Aside from a rebase, this version includes a minor bug fix for
> "KVM: selftests: Update kvm_init_vm_address_properties() for TDX" which
> was called out in v6 by Ira Weiny.

Folks, this series is completely unacceptable.  Please read through
Documentation/process/maintainer-kvm-x86.rst and fix the myriad issues with this
series.

I will provide detailed feedback on this version to help move things along, but
if v9 doesn't show a marked improvment, don't expect much more than a formletter
response.  I have made my expectations for KVM x86 abundantly clear.

Process violations aside, I am also extremely frustrated that seemingly no effort
has been made to update and polish this series for upstream inclusion.  As Ira
pointed out, there are references to terminology that we haven't used in *years*.

 : If guest memory is backed by restricted memfd
 : 
 : + UPM is being used, hence encrypted memory region has to be
 :   registered
 : + Can avoid making a copy of guest memory before getting TDX to
 :   initialize the memory region

And then there's code like this

 +#define KVM_MAX_CPUID_ENTRIES 256
 +
 +#define CPUID_EXT_VMX                  BIT(5)
 +#define CPUID_EXT_SMX                  BIT(6)
 +#define CPUID_PSE36                    BIT(17)
 +#define CPUID_7_0_EBX_TSC_ADJUST       BIT(1)
 +#define CPUID_7_0_EBX_SGX              BIT(2)
 +#define CPUID_7_0_EBX_INTEL_PT         BIT(25)
 +#define CPUID_7_0_ECX_SGX_LC           BIT(30)
 +#define CPUID_APM_INVTSC               BIT(8)
 +#define CPUID_8000_0008_EBX_WBNOINVD   BIT(9)
 +#define CPUID_EXT_PDCM                 BIT(15)

which is just... ugh.

Please make cleaning up this mess the highest priority for TDX upstreaming.  I
am _thrilled_ (honestly) at the amount test coverage that has been developed for
TDX.  But I am equally angry that so much effort is being put into newfangled
TDX features, and that so little effort is being put into helping review and
polish this series.  I refuse to believe that I am the only person that could
look at the above code and come to the conclusion that it's simply unnacceptable.

Y'all _know_ I am stretched thin, please help distribute the load.