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* KVM: SVM: Add KVM_SEV_SNP_LAUNCH_FINISH commandBrijesh Singh2022-07-131-0/+22
| | | | | | | | | | | | | | | | The KVM_SEV_SNP_LAUNCH_FINISH finalize the cryptographic digest and stores it as the measurement of the guest at launch. While finalizing the launch flow, it also issues the LAUNCH_UPDATE command to encrypt the VMSA pages. If its an SNP guest, then VMSA was added in the RMP entry as a guest owned page and also removed from the kernel direct map so flush it later after it is transitioned back to hypervisor state and restored in the direct map. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
* KVM: SVM: Add KVM_SEV_SNP_LAUNCH_UPDATE commandBrijesh Singh2022-07-131-0/+29
| | | | | | | | | | | | | | | | | The KVM_SEV_SNP_LAUNCH_UPDATE command can be used to insert data into the guest's memory. The data is encrypted with the cryptographic context created with the KVM_SEV_SNP_LAUNCH_START. In addition to the inserting data, it can insert a two special pages into the guests memory: the secrets page and the CPUID page. While terminating the guest, reclaim the guest pages added in the RMP table. If the reclaim fails, then the page is no longer safe to be released back to the system and leak them. For more information see the SEV-SNP specification. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
* KVM: SVM: Add KVM_SEV_SNP_LAUNCH_START commandBrijesh Singh2022-07-131-0/+24
| | | | | | | | | | | 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. If the guest is expected to be migrated, the command also binds a migration agent (MA) to the guest. For more information see the SEV-SNP specification. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
* KVM: SVM: Add KVM_SNP_INIT commandBrijesh Singh2022-07-131-0/+27
| | | | | | | | | | | | | | The KVM_SNP_INIT command is used by the hypervisor to initialize the SEV-SNP platform context. In a typical workflow, this command should be the first command issued. When creating SEV-SNP guest, the VMM must use this command instead of the KVM_SEV_INIT or KVM_SEV_ES_INIT. The flags value must be zero, it will be extended in future SNP support to communicate the optional features (such as restricted INT injection etc). Co-developed-by: Pavan Kumar Paluri <papaluri@amd.com> Signed-off-by: Pavan Kumar Paluri <papaluri@amd.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
* KVM: X86/MMU: Fix shadowing 5-level NPT for 4-level NPT L1 guestLai Jiangshan2022-04-291-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When shadowing 5-level NPT for 4-level NPT L1 guest, the root_sp is allocated with role.level = 5 and the guest pagetable's root gfn. And root_sp->spt[0] is also allocated with the same gfn and the same role except role.level = 4. Luckily that they are different shadow pages, but only root_sp->spt[0] is the real translation of the guest pagetable. Here comes a problem: If the guest switches from gCR4_LA57=0 to gCR4_LA57=1 (or vice verse) and uses the same gfn as the root page for nested NPT before and after switching gCR4_LA57. The host (hCR4_LA57=1) might use the same root_sp for the guest even the guest switches gCR4_LA57. The guest will see unexpected page mapped and L2 may exploit the bug and hurt L1. It is lucky that the problem can't hurt L0. And three special cases need to be handled: The root_sp should be like role.direct=1 sometimes: its contents are not backed by gptes, root_sp->gfns is meaningless. (For a normal high level sp in shadow paging, sp->gfns is often unused and kept zero, but it could be relevant and meaningful if sp->gfns is used because they are backed by concrete gptes.) For such root_sp in the case, root_sp is just a portal to contribute root_sp->spt[0], and root_sp->gfns should not be used and root_sp->spt[0] should not be dropped if gpte[0] of the guest root pagetable is changed. Such root_sp should not be accounted too. So add role.passthrough to distinguish the shadow pages in the hash when gCR4_LA57 is toggled and fix above special cases by using it in kvm_mmu_page_{get|set}_gfn() and sp_has_gptes(). Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Message-Id: <20220420131204.2850-3-jiangshanlai@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Documentation: KVM: Add SPDX-License-Identifier tagLike Xu2022-04-113-1/+5
| | | | | | | | | | | | | +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>
* Documentation: KVM: add virtual CPU errata documentationPaolo Bonzini2022-03-292-0/+40
| | | | | | | | | | | | Add a file to document all the different ways in which the virtual CPU emulation is imperfect. Include an example to show how to document such errata. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Message-Id: <20220322110712.222449-3-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Documentation: KVM: add separate directories for architecture-specific ↵Paolo Bonzini2022-03-2910-0/+2955
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>