| Message ID | 20210819154910.1064090-3-pgonda@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add AMD SEV and SEV-ES intra host migration support | expand |
On Thu, Aug 19, 2021 at 8:49 AM Peter Gonda <pgonda@google.com> wrote: > > For SEV-ES to work with intra host migration the VMSAs, GHCB metadata, > and other SEV-ES info needs to be preserved along with the guest's > memory. > > Signed-off-by: Peter Gonda <pgonda@google.com> > Cc: Marc Orr <marcorr@google.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: Sean Christopherson <seanjc@google.com> > Cc: David Rientjes <rientjes@google.com> > Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> > Cc: Brijesh Singh <brijesh.singh@amd.com> > Cc: Vitaly Kuznetsov <vkuznets@redhat.com> > Cc: Wanpeng Li <wanpengli@tencent.com> > Cc: Jim Mattson <jmattson@google.com> > Cc: Joerg Roedel <joro@8bytes.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Borislav Petkov <bp@alien8.de> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > --- > arch/x86/kvm/svm/sev.c | 58 +++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 55 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 2d98b56b6f8c..970d75c34e9a 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -1554,6 +1554,53 @@ static void migrate_info_from(struct kvm_sev_info *dst, > list_replace_init(&src->regions_list, &dst->regions_list); > } > > +static int migrate_vmsa_from(struct kvm *dst, struct kvm *src) > +{ > + int i, num_vcpus; > + struct kvm_vcpu *dst_vcpu, *src_vcpu; > + struct vcpu_svm *dst_svm, *src_svm; > + > + num_vcpus = atomic_read(&dst->online_vcpus); > + if (num_vcpus != atomic_read(&src->online_vcpus)) { > + pr_warn_ratelimited( > + "Source and target VMs must have same number of vCPUs.\n"); > + return -EINVAL; > + } > + > + for (i = 0; i < num_vcpus; ++i) { > + src_vcpu = src->vcpus[i]; > + if (!src_vcpu->arch.guest_state_protected) { > + pr_warn_ratelimited( > + "Source ES VM vCPUs must have protected state.\n"); > + return -EINVAL; > + } > + } > + > + for (i = 0; i < num_vcpus; ++i) { > + src_vcpu = src->vcpus[i]; > + src_svm = to_svm(src_vcpu); > + dst_vcpu = dst->vcpus[i]; > + dst_svm = to_svm(dst_vcpu); > + > + dst_vcpu->vcpu_id = src_vcpu->vcpu_id; > + dst_svm->vmsa = src_svm->vmsa; > + src_svm->vmsa = NULL; > + dst_svm->ghcb = src_svm->ghcb; > + src_svm->ghcb = NULL; > + dst_svm->vmcb->control.ghcb_gpa = > + src_svm->vmcb->control.ghcb_gpa; Should we clear `src_svm->vmcb->control.ghcb_gpa`? (All the other fields in `srv_svm` that are copied are then cleared, except for this one.) Aside: Do we really need to clear all of the fields in `src_svm` after they're copied over? It might be worth adding a comment to explain why we're clearing them. It's not immediately obvious to me why we're doing that. > + dst_svm->ghcb_sa = src_svm->ghcb_sa; > + src_svm->ghcb_sa = NULL; > + dst_svm->ghcb_sa_len = src_svm->ghcb_sa_len; > + src_svm->ghcb_sa_len = 0; > + dst_svm->ghcb_sa_sync = src_svm->ghcb_sa_sync; > + src_svm->ghcb_sa_sync = false; > + dst_svm->ghcb_sa_free = src_svm->ghcb_sa_free; > + src_svm->ghcb_sa_free = false; > + } > + return 0; > +} > + > int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > { > struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; > @@ -1565,7 +1612,7 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > if (ret) > return ret; > > - if (!sev_guest(kvm) || sev_es_guest(kvm)) { > + if (!sev_guest(kvm)) { > ret = -EINVAL; > pr_warn_ratelimited("VM must be SEV enabled to migrate to.\n"); > goto out_unlock; > @@ -1589,15 +1636,20 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > if (ret) > goto out_fput; > > - if (!sev_guest(source_kvm) || sev_es_guest(source_kvm)) { > + if (!sev_guest(source_kvm)) { > ret = -EINVAL; > pr_warn_ratelimited( > "Source VM must be SEV enabled to migrate from.\n"); > goto out_source; > } > > + if (sev_es_guest(kvm)) { > + ret = migrate_vmsa_from(kvm, source_kvm); > + if (ret) > + goto out_source; > + } > migrate_info_from(dst_sev, &to_kvm_svm(source_kvm)->sev_info); > - ret = 0; > + ret = 0; nit: looks like there's some space issue on this line. Since I believe this line was introduced in the previous patch, I wouldn't expect it to show up with a diff in patch #2. > out_source: > svm_unlock_after_migration(source_kvm); > -- > 2.33.0.rc1.237.g0d66db33f3-goog This patch looks good overall to me. Reviewed-by: Marc Orr <marcorr@google.com>
On Fri, Aug 20, 2021 at 3:01 PM Marc Orr <marcorr@google.com> wrote: > > On Thu, Aug 19, 2021 at 8:49 AM Peter Gonda <pgonda@google.com> wrote: > > > > For SEV-ES to work with intra host migration the VMSAs, GHCB metadata, > > and other SEV-ES info needs to be preserved along with the guest's > > memory. > > > > Signed-off-by: Peter Gonda <pgonda@google.com> > > Cc: Marc Orr <marcorr@google.com> > > Cc: Paolo Bonzini <pbonzini@redhat.com> > > Cc: Sean Christopherson <seanjc@google.com> > > Cc: David Rientjes <rientjes@google.com> > > Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> > > Cc: Brijesh Singh <brijesh.singh@amd.com> > > Cc: Vitaly Kuznetsov <vkuznets@redhat.com> > > Cc: Wanpeng Li <wanpengli@tencent.com> > > Cc: Jim Mattson <jmattson@google.com> > > Cc: Joerg Roedel <joro@8bytes.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > Cc: Ingo Molnar <mingo@redhat.com> > > Cc: Borislav Petkov <bp@alien8.de> > > Cc: "H. Peter Anvin" <hpa@zytor.com> > > Cc: kvm@vger.kernel.org > > Cc: linux-kernel@vger.kernel.org > > --- > > arch/x86/kvm/svm/sev.c | 58 +++++++++++++++++++++++++++++++++++++++--- > > 1 file changed, 55 insertions(+), 3 deletions(-) > > > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > > index 2d98b56b6f8c..970d75c34e9a 100644 > > --- a/arch/x86/kvm/svm/sev.c > > +++ b/arch/x86/kvm/svm/sev.c > > @@ -1554,6 +1554,53 @@ static void migrate_info_from(struct kvm_sev_info *dst, > > list_replace_init(&src->regions_list, &dst->regions_list); > > } > > > > +static int migrate_vmsa_from(struct kvm *dst, struct kvm *src) > > +{ > > + int i, num_vcpus; > > + struct kvm_vcpu *dst_vcpu, *src_vcpu; > > + struct vcpu_svm *dst_svm, *src_svm; > > + > > + num_vcpus = atomic_read(&dst->online_vcpus); > > + if (num_vcpus != atomic_read(&src->online_vcpus)) { > > + pr_warn_ratelimited( > > + "Source and target VMs must have same number of vCPUs.\n"); > > + return -EINVAL; > > + } > > + > > + for (i = 0; i < num_vcpus; ++i) { > > + src_vcpu = src->vcpus[i]; > > + if (!src_vcpu->arch.guest_state_protected) { > > + pr_warn_ratelimited( > > + "Source ES VM vCPUs must have protected state.\n"); > > + return -EINVAL; > > + } > > + } > > + > > + for (i = 0; i < num_vcpus; ++i) { > > + src_vcpu = src->vcpus[i]; > > + src_svm = to_svm(src_vcpu); > > + dst_vcpu = dst->vcpus[i]; > > + dst_svm = to_svm(dst_vcpu); > > + > > + dst_vcpu->vcpu_id = src_vcpu->vcpu_id; > > + dst_svm->vmsa = src_svm->vmsa; > > + src_svm->vmsa = NULL; > > + dst_svm->ghcb = src_svm->ghcb; > > + src_svm->ghcb = NULL; > > + dst_svm->vmcb->control.ghcb_gpa = > > + src_svm->vmcb->control.ghcb_gpa; > > Should we clear `src_svm->vmcb->control.ghcb_gpa`? (All the other > fields in `srv_svm` that are copied are then cleared, except for this > one.) Aside: Do we really need to clear all of the fields in `src_svm` > after they're copied over? It might be worth adding a comment to > explain why we're clearing them. It's not immediately obvious to me > why we're doing that. Cleared in the next version and added a comment. We don't want to leave references for the source VM to edit the VMSA or GHCB after the migration. > > > + dst_svm->ghcb_sa = src_svm->ghcb_sa; > > + src_svm->ghcb_sa = NULL; > > + dst_svm->ghcb_sa_len = src_svm->ghcb_sa_len; > > + src_svm->ghcb_sa_len = 0; > > + dst_svm->ghcb_sa_sync = src_svm->ghcb_sa_sync; > > + src_svm->ghcb_sa_sync = false; > > + dst_svm->ghcb_sa_free = src_svm->ghcb_sa_free; > > + src_svm->ghcb_sa_free = false; > > + } > > + return 0; > > +} > > + > > int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > > { > > struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; > > @@ -1565,7 +1612,7 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > > if (ret) > > return ret; > > > > - if (!sev_guest(kvm) || sev_es_guest(kvm)) { > > + if (!sev_guest(kvm)) { > > ret = -EINVAL; > > pr_warn_ratelimited("VM must be SEV enabled to migrate to.\n"); > > goto out_unlock; > > @@ -1589,15 +1636,20 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) > > if (ret) > > goto out_fput; > > > > - if (!sev_guest(source_kvm) || sev_es_guest(source_kvm)) { > > + if (!sev_guest(source_kvm)) { > > ret = -EINVAL; > > pr_warn_ratelimited( > > "Source VM must be SEV enabled to migrate from.\n"); > > goto out_source; > > } > > > > + if (sev_es_guest(kvm)) { > > + ret = migrate_vmsa_from(kvm, source_kvm); > > + if (ret) > > + goto out_source; > > + } > > migrate_info_from(dst_sev, &to_kvm_svm(source_kvm)->sev_info); > > - ret = 0; > > + ret = 0; > > nit: looks like there's some space issue on this line. Since I believe > this line was introduced in the previous patch, I wouldn't expect it > to show up with a diff in patch #2. Fixed thanks. > > > out_source: > > svm_unlock_after_migration(source_kvm); > > -- > > 2.33.0.rc1.237.g0d66db33f3-goog > > This patch looks good overall to me. > > Reviewed-by: Marc Orr <marcorr@google.com>
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 2d98b56b6f8c..970d75c34e9a 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1554,6 +1554,53 @@ static void migrate_info_from(struct kvm_sev_info *dst, list_replace_init(&src->regions_list, &dst->regions_list); } +static int migrate_vmsa_from(struct kvm *dst, struct kvm *src) +{ + int i, num_vcpus; + struct kvm_vcpu *dst_vcpu, *src_vcpu; + struct vcpu_svm *dst_svm, *src_svm; + + num_vcpus = atomic_read(&dst->online_vcpus); + if (num_vcpus != atomic_read(&src->online_vcpus)) { + pr_warn_ratelimited( + "Source and target VMs must have same number of vCPUs.\n"); + return -EINVAL; + } + + for (i = 0; i < num_vcpus; ++i) { + src_vcpu = src->vcpus[i]; + if (!src_vcpu->arch.guest_state_protected) { + pr_warn_ratelimited( + "Source ES VM vCPUs must have protected state.\n"); + return -EINVAL; + } + } + + for (i = 0; i < num_vcpus; ++i) { + src_vcpu = src->vcpus[i]; + src_svm = to_svm(src_vcpu); + dst_vcpu = dst->vcpus[i]; + dst_svm = to_svm(dst_vcpu); + + dst_vcpu->vcpu_id = src_vcpu->vcpu_id; + dst_svm->vmsa = src_svm->vmsa; + src_svm->vmsa = NULL; + dst_svm->ghcb = src_svm->ghcb; + src_svm->ghcb = NULL; + dst_svm->vmcb->control.ghcb_gpa = + src_svm->vmcb->control.ghcb_gpa; + dst_svm->ghcb_sa = src_svm->ghcb_sa; + src_svm->ghcb_sa = NULL; + dst_svm->ghcb_sa_len = src_svm->ghcb_sa_len; + src_svm->ghcb_sa_len = 0; + dst_svm->ghcb_sa_sync = src_svm->ghcb_sa_sync; + src_svm->ghcb_sa_sync = false; + dst_svm->ghcb_sa_free = src_svm->ghcb_sa_free; + src_svm->ghcb_sa_free = false; + } + return 0; +} + int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) { struct kvm_sev_info *dst_sev = &to_kvm_svm(kvm)->sev_info; @@ -1565,7 +1612,7 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) if (ret) return ret; - if (!sev_guest(kvm) || sev_es_guest(kvm)) { + if (!sev_guest(kvm)) { ret = -EINVAL; pr_warn_ratelimited("VM must be SEV enabled to migrate to.\n"); goto out_unlock; @@ -1589,15 +1636,20 @@ int svm_vm_migrate_from(struct kvm *kvm, unsigned int source_fd) if (ret) goto out_fput; - if (!sev_guest(source_kvm) || sev_es_guest(source_kvm)) { + if (!sev_guest(source_kvm)) { ret = -EINVAL; pr_warn_ratelimited( "Source VM must be SEV enabled to migrate from.\n"); goto out_source; } + if (sev_es_guest(kvm)) { + ret = migrate_vmsa_from(kvm, source_kvm); + if (ret) + goto out_source; + } migrate_info_from(dst_sev, &to_kvm_svm(source_kvm)->sev_info); - ret = 0; + ret = 0; out_source: svm_unlock_after_migration(source_kvm);
For SEV-ES to work with intra host migration the VMSAs, GHCB metadata, and other SEV-ES info needs to be preserved along with the guest's memory. Signed-off-by: Peter Gonda <pgonda@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Dr. David Alan Gilbert <dgilbert@redhat.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: Jim Mattson <jmattson@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- arch/x86/kvm/svm/sev.c | 58 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 55 insertions(+), 3 deletions(-)