-----Original Message----- From: Erdem Aktas erdemaktas@google.com Sent: Tuesday, July 27, 2021 2:38 AM To: linux-kselftest@vger.kernel.org Cc: erdemaktas@google.com; Paolo Bonzini pbonzini@redhat.com; Shuah Khan shuah@kernel.org; Andrew Jones drjones@redhat.com; Ben Gardon bgardon@google.com; Peter Xu peterx@redhat.com; Sean Christopherson seanjc@google.com; Christian Borntraeger borntraeger@de.ibm.com; Eric Auger eric.auger@redhat.com; Emanuele Giuseppe Esposito eesposit@redhat.com; Ricardo Koller ricarkol@google.com; Duan, Zhenzhong zhenzhong.duan@intel.com; Aaron Lewis aaronlewis@google.com; Jim Mattson jmattson@google.com; Oliver Upton oupton@google.com; Vitaly Kuznetsov vkuznets@redhat.com; Peter Shier pshier@google.com; Axel Rasmussen axelrasmussen@google.com; Yanan Wang wangyanan55@huawei.com; Maciej S. Szmigiero maciej.szmigiero@oracle.com; David Matlack dmatlack@google.com; Like Xu like.xu@linux.intel.com; open list linux-kernel@vger.kernel.org; open list:KERNEL VIRTUAL MACHINE (KVM) kvm@vger.kernel.org Subject: [RFC PATCH 0/4] TDX KVM selftests
TDX stands for Trust Domain Extensions which isolates VMs from the virtual- machine manager (VMM)/hypervisor and any other software on the platform.
Intel has recently submitted a set of RFC patches for KVM support for TDX and more information can be found on the latest TDX Support Patches: https://lkml.org/lkml/2021/7/2/558
Due to the nature of the confidential computing environment that TDX provides, it is very difficult to verify/test the KVM support. TDX requires UEFI and the guest kernel to be enlightened which are all under development.
We are working on a set of selftests to close this gap and be able to verify the KVM functionality to support TDX lifecycle and GHCI [1] interface.
We are looking for any feedback on:
- Patch series itself
- Any suggestion on how we should approach testing TDX functionality.
Does selftests seems reasonable or should we switch to using KVM unit tests. I would be happy to get some perspective on how KVM unit tests can help us more.
- Any test case or scenario that we should add.
- Anything else I have not thought of yet.
Current patch series provide the following capabilities:
- Provide helper functions to create a TD (Trusted Domain) using the KVM ioctls
- Provide helper functions to create a guest image that can include any testing code
- Provide helper functions and wrapper functions to write testing code using GHCI interface
- Add a test case that verifies TDX life cycle
- Add a test case that verifies TDX GHCI port IO
TODOs:
- Use existing function to create page tables dynamically (ie __virt_pg_map())
- Remove arbitrary defined magic numbers for data structure offsets
- Add TDVMCALL for error reporting
- Add additional test cases as some listed below
- Add #VE handlers to help testing more complicated test cases
Other test cases that we are planning to add: (with credit to sagis@google.com)
VM call interface Input Output Result GetTdVmCallInfo R12=0 None VMCALL_SUCCESS MapGPA Map private page (GPA.S=0) VMCALL_SUCCESS MapGPA Map shared page (GPA.S=1) VMCALL_SUCCESS MapGPA Map already private page as private VMCALL_INVALID_OPERAND MapGPA Map already shared page as shared VMCALL_INVALID_OPERAND GetQuote ReportFatalError SetupEventNotifyInterrupt Valid interrupt value (32:255) VMCALL_SUCCESS SetupEventNotifyInterrupt Invalid value (>255) VMCALL_INVALID_OPERAND Instruction.CPUID R12(EAX)=1, R13(ECX)=0 EBX[8:15]=0x8 EBX[16:23]=X EBX[24:31]=vcpu_id ECX[0]=1 ECX[12]=Y Instruction.CPUID R12(EAX)=1, R13(ECX)=4 VMCALL_INVALID_OPERAND VE.RequestMMIO Instruction.HLT VMCALL_SUCCESS Instruction.IO Read/Write 1/2/4 bytes VMCALL_SUCCESS Instruction.IO Read/Write 3 bytes VMCALL_INVALID_OPERAND Instruction.RDMSR Accessible register R11=msr_value VMCALL_SUCCESS Inaccessible register VMCALL_INVALID_OPERAND Instruction.RDMSR Accessible register VMCALL_SUCCESS Inaccessible register VMCALL_INVALID_OPERAND INSTRUCTION.PCONFIG
[1] Intel TDX Guest-Hypervisor Communication Interface
https://software.intel.com/content/dam/develop/external/us/en/document s/intel-tdx-guest-hypervisor-communication-interface.pdf
Erdem Aktas (4): KVM: selftests: Add support for creating non-default type VMs KVM: selftest: Add helper functions to create TDX VMs
In tools/testing/selftests/kvm/Makefile, '/lib/x86_64/tdx_lib.c' should be changed to 'lib/x86_64/tdx_lib.c' After that, build and test passes.
# ./tdx_vm_tests Verifying TD lifecycle: Verifying TD IO Exit: ... IO WRITE: OK ... IO READ: OK ... IO verify read/write values: OK
Tested-by: Zhenzhong Duan zhenzhong.duan@intel.com
Regards Zhenzhong