On 9/6/23 10:14, Peter Gonda wrote:
Currently if an SEV-ES VM shuts down userspace sees KVM_RUN struct with
s/down userspace/down, userspace/
only the INVALID_ARGUMENT. This is a very limited amount of information
to debug the situation. Instead KVM can return a
KVM_EXIT_SHUTDOWN to alert userspace the VM is shutting down and
is not usable any further.
Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
arch/x86/kvm/svm/svm.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 956726d867aa..cecf6a528c9b 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2131,12 +2131,14 @@ static int shutdown_interception(struct kvm_vcpu *vcpu)
* The VM save area has already been encrypted so it
* cannot be reinitialized - just terminate.
*/
- if (sev_es_guest(vcpu->kvm))
- return -EINVAL;
+ if (sev_es_guest(vcpu->kvm)) {
+ kvm_run->exit_reason = KVM_EXIT_SHUTDOWN;
+ return 0;
+ }
Just a nit... feel free to ignore, but, since KVM_EXIT_SHUTDOWN is also
set at the end of the function and I don't think kvm_vcpu_reset() clears
the value from kvm_run, you could just set kvm_run->exit_reason on entry
and just return 0 early for an SEV-ES guest.
Overall, though:
Acked-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Thanks,
Tom
/*
* VMCB is undefined after a SHUTDOWN intercept. INIT the vCPU to put
- * the VMCB in a known good state. Unfortuately, KVM doesn't have
+ * the VMCB in a known good state. Unfortunately, KVM doesn't have
* KVM_MP_STATE_SHUTDOWN and can't add it without potentially breaking
* userspace. At a platform view, INIT is acceptable behavior as
* there exist bare metal platforms that automatically INIT the CPU
