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2024-05-12KVM: SEV: Add KVM_SEV_SNP_LAUNCH_FINISH commandBrijesh Singh
Add a KVM_SEV_SNP_LAUNCH_FINISH command to finalize the cryptographic launch digest which stores the measurement of the guest at launch time. Also extend the existing SNP firmware data structures to support disabling the use of Versioned Chip Endorsement Keys (VCEK) by guests as part of this command. While finalizing the launch flow, the code also issues the LAUNCH_UPDATE SNP firmware commands to encrypt/measure the initial VMSA pages for each configured vCPU, which requires setting the RMP entries for those pages to private, so also add handling to clean up the RMP entries for these pages whening freeing vCPUs during shutdown. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Harald Hoyer <harald@profian.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Message-ID: <20240501085210.2213060-8-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-12KVM: SEV: Add KVM_SEV_SNP_LAUNCH_UPDATE commandBrijesh Singh
A key aspect of a launching an SNP guest is initializing it with a known/measured payload which is then encrypted into guest memory as pre-validated private pages and then measured into the cryptographic launch context created with KVM_SEV_SNP_LAUNCH_START so that the guest can attest itself after booting. Since all private pages are provided by guest_memfd, make use of the kvm_gmem_populate() interface to handle this. The general flow is that guest_memfd will handle allocating the pages associated with the GPA ranges being initialized by each particular call of KVM_SEV_SNP_LAUNCH_UPDATE, copying data from userspace into those pages, and then the post_populate callback will do the work of setting the RMP entries for these pages to private and issuing the SNP firmware calls to encrypt/measure them. For more information see the SEV-SNP specification. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Message-ID: <20240501085210.2213060-7-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-12KVM: SEV: Add KVM_SEV_SNP_LAUNCH_START commandBrijesh Singh
KVM_SEV_SNP_LAUNCH_START begins the launch process for an SEV-SNP guest. The command initializes a cryptographic digest context used to construct the measurement of the guest. Other commands can then at that point be used to load/encrypt data into the guest's initial launch image. For more information see the SEV-SNP specification. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Message-ID: <20240501085210.2213060-6-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-05-07KVM: SEV: Allow per-guest configuration of GHCB protocol versionMichael Roth
The GHCB protocol version may be different from one guest to the next. Add a field to track it for each KVM instance and extend KVM_SEV_INIT2 to allow it to be configured by userspace. Now that all SEV-ES support for GHCB protocol version 2 is in place, go ahead and default to it when creating SEV-ES guests through the new KVM_SEV_INIT2 interface. Keep the older KVM_SEV_ES_INIT interface restricted to GHCB protocol version 1. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-ID: <20240501071048.2208265-5-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-11KVM: SEV: introduce KVM_SEV_INIT2 operationPaolo Bonzini
The idea that no parameter would ever be necessary when enabling SEV or SEV-ES for a VM was decidedly optimistic. In fact, in some sense it's already a parameter whether SEV or SEV-ES is desired. Another possible source of variability is the desired set of VMSA features, as that affects the measurement of the VM's initial state and cannot be changed arbitrarily by the hypervisor. Create a new sub-operation for KVM_MEMORY_ENCRYPT_OP that can take a struct, and put the new op to work by including the VMSA features as a field of the struct. The existing KVM_SEV_INIT and KVM_SEV_ES_INIT use the full set of supported VMSA features for backwards compatibility. The struct also includes the usual bells and whistles for future extensibility: a flags field that must be zero for now, and some padding at the end. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20240404121327.3107131-13-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-11KVM: SEV: publish supported VMSA featuresPaolo Bonzini
Compute the set of features to be stored in the VMSA when KVM is initialized; move it from there into kvm_sev_info when SEV is initialized, and then into the initial VMSA. The new variable can then be used to return the set of supported features to userspace, via the KVM_GET_DEVICE_ATTR ioctl. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com> Message-ID: <20240404121327.3107131-6-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18Documentation: kvm/sev: clarify usage of KVM_MEMORY_ENCRYPT_OPPaolo Bonzini
Explain that it operates on the VM file descriptor, and also clarify how detection of SEV operates on old kernels predating commit 2da1ed62d55c ("KVM: SVM: document KVM_MEM_ENCRYPT_OP, let userspace detect if SEV is available"). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18Documentation: kvm/sev: separate description of firmwarePaolo Bonzini
The description of firmware is included part under the "SEV Key Management" header, part under the KVM_SEV_INIT ioctl. Put these two bits together and and rename "SEV Key Management" to what it actually is, namely a description of the KVM_MEMORY_ENCRYPT_OP API. Reviewed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-07-04Documentation: KVM: SEV: add a missing backtickChangyuan Lyu
``ENOTTY` -> ``ENOTTY``. Signed-off-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20230624165858.21777-1-changyuanl@google.com>
2023-02-02Documentation: KVM: Update AMD memory encryption linkWyes Karny
Update AMD memory encryption white-paper document link. Previous link is not available. Update new available link. Signed-off-by: Wyes Karny <wyes.karny@amd.com> Reviewed-by: Carlos Bilbao <carlos.bilbao@amd.com> Link: https://lore.kernel.org/r/20230125175948.21100-1-wyes.karny@amd.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-08-26crypto: ccp - Initialize PSP when reading psp data file failedJacky Li
Currently the OS fails the PSP initialization when the file specified at 'init_ex_path' does not exist or has invalid content. However the SEV spec just requires users to allocate 32KB of 0xFF in the file, which can be taken care of by the OS easily. To improve the robustness during the PSP init, leverage the retry mechanism and continue the init process: Before the first INIT_EX call, if the content is invalid or missing, continue the process by feeding those contents into PSP instead of aborting. PSP will then override it with 32KB 0xFF and return SEV_RET_SECURE_DATA_INVALID status code. In the second INIT_EX call, this 32KB 0xFF content will then be fed and PSP will write the valid data to the file. In order to do this, sev_read_init_ex_file should only be called once for the first INIT_EX call. Calling it again for the second INIT_EX call will cause the invalid file content overwriting the valid 32KB 0xFF data provided by PSP in the first INIT_EX call. Co-developed-by: Peter Gonda <pgonda@google.com> Signed-off-by: Peter Gonda <pgonda@google.com> Signed-off-by: Jacky Li <jackyli@google.com> Reported-by: Alper Gun <alpergun@google.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-04-11Documentation: KVM: Add SPDX-License-Identifier tagLike Xu
+new file mode 100644 +WARNING: Missing or malformed SPDX-License-Identifier tag in line 1 +#27: FILE: Documentation/virt/kvm/x86/errata.rst:1: Opportunistically update all other non-added KVM documents and remove a new extra blank line at EOF for x86/errata.rst. Signed-off-by: Like Xu <likexu@tencent.com> Message-Id: <20220406063715.55625-5-likexu@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-29Documentation: KVM: add separate directories for architecture-specific ↵Paolo Bonzini
documentation ARM already has an arm/ subdirectory, but s390 and x86 do not even though they have a relatively large number of files specific to them. Create new directories in Documentation/virt/kvm for these two architectures as well. While at it, group the API documentation and the developer documentation in the table of contents. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220322110712.222449-2-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>