Sorry that I made mistake when copy and paste Jim's email address :( Remove the wrong email address (mattson@xxxxxxxxxx) and add the correct one (jmattson@xxxxxxxxx). Really apologize for the noise. Thanks, -Kai On Wed, 2021-01-06 at 14:55 +1300, Kai Huang wrote: > --- Disclaimer --- > > These patches were originally written by Sean Christopherson while at Intel. > Now that Sean has left Intel, I (Kai) have taken over getting them upstream. > This series needs more review before it can be merged. It is being posted > publicly and under RFC so Sean and others can review it. Maintainers are safe > ignoring it for now. > > ------------------ > > Hi all, > > This series adds KVM SGX virtualization support. The first 12 patches starting > with x86/sgx or x86/cpu.. are necessary changes to x86 and SGX core/driver to > support KVM SGX virtualization, while the rest are patches to KVM subsystem. > > Please help to review this series. Also I'd like to hear what is the proper > way to merge this series, since it contains change to both x86/SGX and KVM > subsystem. Any feedback is highly appreciated. And please let me know if I > forgot to CC anyone, or anyone wants to be removed from CC. Thanks in advance! > > This series is based against latest tip tree's x86/sgx branch. You can also get > the code from tip branch of kvm-sgx repo on github: > > https://github.com/intel/kvm-sgx.git tip > > It also requires Qemu changes to create VM with SGX support. You can find Qemu > repo here: > > https://github.com/intel/qemu-sgx.git next > > Please refer to README.md of above qemu-sgx repo for detail on how to create > guest with SGX support. At meantime, for your quick reference you can use below > command to create SGX guest: > > #qemu-system-x86_64 -smp 4 -m 2G -drive file=<your_vm_image>,if=virtio \ > -cpu host,+sgx_provisionkey \ > -sgx-epc id=epc1,memdev=mem1 \ > -object memory-backend-epc,id=mem1,size=64M,prealloc > > Please note that the SGX relevant part is: > > -cpu host,+sgx_provisionkey \ > -sgx-epc id=epc1,memdev=mem1 \ > -object memory-backend-epc,id=mem1,size=64M,prealloc > > And you can change other parameters of your qemu command based on your needs. > > ========= > KVM SGX virtualization Overview > > - Virtual EPC > > "Virtual EPC" is the EPC section exposed by KVM to guest so SGX software in > guest can discover it and use it to create SGX enclaves. KVM exposes SGX to > guest via CPUID, and exposes one or more "virtual EPC" sections for guest. > The size of "virtual EPC" is passed as Qemu parameter when creating the > guest, and the base address is calcualted internally according to guest's > configuration. > > To support virtual EPC, add a new misc device /dev/sgx_virt_epc to SGX > core/driver to allow userspace (Qemu) to allocate "raw" EPC, and use it as > "virtual EPC" for guest. Obviously, unlike EPC allocated for host SGX driver, > virtual EPC allocated via /dev/sgx_virt_epc doesn't have enclave associated, > and how virtual EPC is used by guest is compeletely controlled by guest's SGX > software. > > Implement the "raw" EPC allocation in the x86 core-SGX subsystem via > /dev/sgx_virt_epc rather than in KVM. Doing so has two major advantages: > > - Does not require changes to KVM's uAPI, e.g. EPC gets handled as > just another memory backend for guests. > > - EPC management is wholly contained in the SGX subsystem, e.g. SGX > does not have to export any symbols, changes to reclaim flows don't > need to be routed through KVM, SGX's dirty laundry doesn't have to > get aired out for the world to see, and so on and so forth. > > The virtual EPC allocated to guests is currently not reclaimable, due to > reclaiming EPC from KVM guests is not currently supported. Due to the > complications of handling reclaim conflicts between guest and host, KVM > EPC oversubscription, which allows total virtual EPC size greater than > physical EPC by being able to reclaiming guests' EPC, is significantly more > complex than basic support for SGX virtualization. > > - Support SGX virtualization without SGX Launch Control unlocked mode > > Although SGX driver requires SGX Launch Control unlocked mode to work, SGX > virtualization doesn't, since how enclave is created is completely controlled > by guest SGX software, which is not necessarily linux. Therefore, this series > allows KVM to expose SGX to guest even SGX Launch Control is in locked mode, > or is not present at all. The reason is the goal of SGX virtualization, or > virtualization in general, is to expose hardware feature to guest, but not to > make assumption how guest will use it. Therefore, KVM should support SGX guest > as long as hardware is able to, to have chance to support more potential use > cases in cloud environment. > > - Support exposing SGX2 > > Due to the same reason above, SGX2 feature detection is added to core SGX code > to allow KVM to expose SGX2 to guest, even currently SGX driver doesn't support > SGX2, because SGX2 can work just fine in guest w/o any interaction to host SGX > driver. > > - Restricit SGX guest access to provisioning key > > To grant guest being able to fully use SGX, guest needs to be able to create > provisioning enclave. However provisioning key is sensitive and is restricted by > /dev/sgx_provision in host SGX driver, therefore KVM SGX virtualization follows > the same role: a new KVM_CAP_SGX_ATTRIBUTE is added to KVM uAPI, and only file > descriptor of /dev/sgx_provision is passed to that CAP by usersppace hypervisor > (Qemu) when creating the guest, it can access provisioning bit. This is done by > making KVM trape ECREATE instruction from guest, and check the provisioning bit > in ECREATE's attribute. > > > Kai Huang (1): > x86/sgx: Add helper to update SGX_LEPUBKEYHASHn MSRs > > Sean Christopherson (22): > x86/sgx: Split out adding EPC page to free list to separate helper > x86/sgx: Add enum for SGX_CHILD_PRESENT error code > x86/sgx: Introduce virtual EPC for use by KVM guests > x86/cpufeatures: Add SGX1 and SGX2 sub-features > x86/cpu/intel: Allow SGX virtualization without Launch Control support > x86/sgx: Expose SGX architectural definitions to the kernel > x86/sgx: Move ENCLS leaf definitions to sgx_arch.h > x86/sgx: Add SGX2 ENCLS leaf definitions (EAUG, EMODPR and EMODT) > x86/sgx: Add encls_faulted() helper > x86/sgx: Add helpers to expose ECREATE and EINIT to KVM > x86/sgx: Move provisioning device creation out of SGX driver > KVM: VMX: Convert vcpu_vmx.exit_reason to a union > KVM: x86: Export kvm_mmu_gva_to_gpa_{read,write}() for SGX (VMX) > KVM: x86: Define new #PF SGX error code bit > KVM: x86: Add SGX feature leaf to reverse CPUID lookup > KVM: VMX: Add basic handling of VM-Exit from SGX enclave > KVM: VMX: Frame in ENCLS handler for SGX virtualization > KVM: VMX: Add SGX ENCLS[ECREATE] handler to enforce CPUID restrictions > KVM: VMX: Add emulation of SGX Launch Control LE hash MSRs > KVM: VMX: Add ENCLS[EINIT] handler to support SGX Launch Control (LC) > KVM: VMX: Enable SGX virtualization for SGX1, SGX2 and LC > KVM: x86: Add capability to grant VM access to privileged SGX > attribute > > Documentation/virt/kvm/api.rst | 23 + > arch/x86/Kconfig | 12 + > arch/x86/include/asm/cpufeature.h | 5 +- > arch/x86/include/asm/cpufeatures.h | 6 +- > arch/x86/include/asm/disabled-features.h | 7 +- > arch/x86/include/asm/kvm_host.h | 5 + > arch/x86/include/asm/required-features.h | 2 +- > arch/x86/include/asm/sgx.h | 19 + > .../cpu/sgx/arch.h => include/asm/sgx_arch.h} | 20 + > arch/x86/include/asm/vmx.h | 1 + > arch/x86/include/uapi/asm/vmx.h | 1 + > arch/x86/kernel/cpu/common.c | 4 + > arch/x86/kernel/cpu/feat_ctl.c | 50 +- > arch/x86/kernel/cpu/sgx/Makefile | 1 + > arch/x86/kernel/cpu/sgx/driver.c | 17 - > arch/x86/kernel/cpu/sgx/encl.c | 2 +- > arch/x86/kernel/cpu/sgx/encls.h | 29 +- > arch/x86/kernel/cpu/sgx/ioctl.c | 23 +- > arch/x86/kernel/cpu/sgx/main.c | 79 ++- > arch/x86/kernel/cpu/sgx/sgx.h | 5 +- > arch/x86/kernel/cpu/sgx/virt.c | 318 ++++++++++++ > arch/x86/kernel/cpu/sgx/virt.h | 14 + > arch/x86/kvm/Makefile | 2 + > arch/x86/kvm/cpuid.c | 58 ++- > arch/x86/kvm/cpuid.h | 1 + > arch/x86/kvm/vmx/nested.c | 70 ++- > arch/x86/kvm/vmx/nested.h | 5 + > arch/x86/kvm/vmx/sgx.c | 462 ++++++++++++++++++ > arch/x86/kvm/vmx/sgx.h | 34 ++ > arch/x86/kvm/vmx/vmcs12.c | 1 + > arch/x86/kvm/vmx/vmcs12.h | 4 +- > arch/x86/kvm/vmx/vmx.c | 171 +++++-- > arch/x86/kvm/vmx/vmx.h | 27 +- > arch/x86/kvm/x86.c | 24 + > include/uapi/linux/kvm.h | 1 + > tools/testing/selftests/sgx/defines.h | 2 +- > 36 files changed, 1366 insertions(+), 139 deletions(-) > create mode 100644 arch/x86/include/asm/sgx.h > rename arch/x86/{kernel/cpu/sgx/arch.h => include/asm/sgx_arch.h} (96%) > create mode 100644 arch/x86/kernel/cpu/sgx/virt.c > create mode 100644 arch/x86/kernel/cpu/sgx/virt.h > create mode 100644 arch/x86/kvm/vmx/sgx.c > create mode 100644 arch/x86/kvm/vmx/sgx.h >
