Message ID | 20211109215101.2211373-2-seanjc@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | KVM: SEV: Bug fix, cleanups and enhancements | expand |
On Tue, Nov 9, 2021 at 2:53 PM Sean Christopherson <seanjc@google.com> wrote: > > Reject COPY_ENC_CONTEXT_FROM if the destination VM has created vCPUs. > KVM relies on SEV activation to occur before vCPUs are created, e.g. to > set VMCB flags and intercepts correctly. > > Fixes: 54526d1fd593 ("KVM: x86: Support KVM VMs sharing SEV context") > Cc: stable@vger.kernel.org > Cc: Peter Gonda <pgonda@google.com> > Cc: Marc Orr <marcorr@google.com> > Cc: Sean Christopherson <seanjc@google.com> > Cc: Nathan Tempelman <natet@google.com> > Cc: Brijesh Singh <brijesh.singh@amd.com> > Cc: Tom Lendacky <thomas.lendacky@amd.com> > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/x86/kvm/svm/sev.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 3e2769855e51..eeec499e4372 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -1775,7 +1775,12 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd) > mutex_unlock(&source_kvm->lock); > mutex_lock(&kvm->lock); > > - if (sev_guest(kvm)) { > + /* > + * Disallow out-of-band SEV/SEV-ES init if the target is already an > + * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being > + * created after SEV/SEV-ES initialization, e.g. to init intercepts. > + */ > + if (sev_guest(kvm) || kvm->created_vcpus) { > ret = -EINVAL; > goto e_mirror_unlock; > } Now that we have some framework for running SEV related selftests, do you mind adding a regression test for this change? > -- > 2.34.0.rc0.344.g81b53c2807-goog >
On Mon, Nov 15, 2021, Peter Gonda wrote: > On Tue, Nov 9, 2021 at 2:53 PM Sean Christopherson <seanjc@google.com> wrote: > > + /* > > + * Disallow out-of-band SEV/SEV-ES init if the target is already an > > + * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being > > + * created after SEV/SEV-ES initialization, e.g. to init intercepts. > > + */ > > + if (sev_guest(kvm) || kvm->created_vcpus) { > > ret = -EINVAL; > > goto e_mirror_unlock; > > } > > Now that we have some framework for running SEV related selftests, do > you mind adding a regression test for this change? Can do, will likely be a few days though.
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 3e2769855e51..eeec499e4372 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1775,7 +1775,12 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd) mutex_unlock(&source_kvm->lock); mutex_lock(&kvm->lock); - if (sev_guest(kvm)) { + /* + * Disallow out-of-band SEV/SEV-ES init if the target is already an + * SEV guest, or if vCPUs have been created. KVM relies on vCPUs being + * created after SEV/SEV-ES initialization, e.g. to init intercepts. + */ + if (sev_guest(kvm) || kvm->created_vcpus) { ret = -EINVAL; goto e_mirror_unlock; }
Reject COPY_ENC_CONTEXT_FROM if the destination VM has created vCPUs. KVM relies on SEV activation to occur before vCPUs are created, e.g. to set VMCB flags and intercepts correctly. Fixes: 54526d1fd593 ("KVM: x86: Support KVM VMs sharing SEV context") Cc: stable@vger.kernel.org Cc: Peter Gonda <pgonda@google.com> Cc: Marc Orr <marcorr@google.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Nathan Tempelman <natet@google.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/svm/sev.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)