On Tue, Sep 5, 2023 at 2:58 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > On Tue, Sep 05, 2023, Peter Gonda wrote: > > Currently if an SEV-ES VM shuts down userspace sees KVM_RUN struct with > > only the INVALID_ARGUMENT. This is a very limited amount of information > > to debug the situation. Instead KVM can return a > > KVM_SYSTEM_EVENT_SEV_TERM to alert userspace the VM is shutting down and > > is not usable any further. This latter point can be enforced using the > > kvm_vm_dead() functionality. > > Add the kvm_vm_dead() thing in a separate patch. If we want to actually harden > KVM against consuming a garbage VMSA then we do need to mark the VM dead, but on > the other hand that will block _all_ KVM ioctls(), which will make debug even > harder. Will do. Do we have better functionality for just blocking running the vCPU? > > > 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 > > > > --- > > > > I am not sure if this is the right path forward maybe just returning > > KVM_EXIT_SHUTDOWN is better. But the current behavior is very unhelpful. > > Ya, KVM_EXIT_SHUTDOWN is better, we should leave KVM_SYSTEM_EVENT_SEV_TERM to > explicit "requests" from the guest. Sounds good to me. I'll send a V2 that just updates to KVM_EXIT_SHUTDOWN.
