[PATCH v12 20/29] KVM: SEV: Add support for GHCB-based termination requests

From: Michael Roth
Date: Fri Mar 29 2024 - 19:03:33 EST


GHCB version 2 adds support for a GHCB-based termination request that
a guest can issue when it reaches an error state and wishes to inform
the hypervisor that it should be terminated. Implement support for that
similarly to GHCB MSR-based termination requests that are already
available to SEV-ES guests via earlier versions of the GHCB protocol.

See 'Termination Request' in the 'Invoking VMGEXIT' section of the GHCB
specification for more details.

Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
---
arch/x86/kvm/svm/sev.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 7dfbf12b454b..9ea13c2de668 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3214,6 +3214,7 @@ static int sev_es_validate_vmgexit(struct vcpu_svm *svm)
case SVM_VMGEXIT_UNSUPPORTED_EVENT:
case SVM_VMGEXIT_HV_FEATURES:
case SVM_VMGEXIT_PSC:
+ case SVM_VMGEXIT_TERM_REQUEST:
break;
default:
reason = GHCB_ERR_INVALID_EVENT;
@@ -3889,6 +3890,14 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)

ret = 1;
break;
+ case SVM_VMGEXIT_TERM_REQUEST:
+ pr_info("SEV-ES guest requested termination: reason %#llx info %#llx\n",
+ control->exit_info_1, control->exit_info_2);
+ vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
+ vcpu->run->system_event.type = KVM_SYSTEM_EVENT_SEV_TERM;
+ vcpu->run->system_event.ndata = 1;
+ vcpu->run->system_event.data[0] = control->ghcb_gpa;
+ break;
case SVM_VMGEXIT_UNSUPPORTED_EVENT:
vcpu_unimpl(vcpu,
"vmgexit: unsupported event - exit_info_1=%#llx, exit_info_2=%#llx\n",
--
2.25.1