[RFC PATCH v3 22/59] KVM: x86: add per-VM flags to disable SMI/INIT/SIPI

isaku.yamahata
2021-11-25T00:24:48Z

From: Isaku Yamahata <isaku.yamahata@intel.com>

Add a flag to let TDX disallow to inject interrupt with delivery
mode of SMI/INIT/SIPI. add a check to reject SMI/INIT interrupt
delivery mode.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/irq_comm.c | 4 ++++
arch/x86/kvm/x86.c | 3 +--
3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 545b556e420c..5ed07f31459e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1133,6 +1133,8 @@ struct kvm_arch {
enum kvm_irqchip_mode irqchip_mode;
u8 nr_reserved_ioapic_pins;
bool eoi_intercept_unsupported;
+ bool smm_unsupported;
+ bool init_sipi_unsupported;

bool disabled_lapic_found;

diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index bcfac99db579..396ccf086bdd 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -128,6 +128,10 @@ static inline bool kvm_msi_route_invalid(struct kvm *kvm,
.data = e->msi.data };
return (kvm->arch.eoi_intercept_unsupported &&
msg.arch_data.is_level) ||
+ (kvm->arch.smm_unsupported &&
+ msg.arch_data.delivery_mode == APIC_DELIVERY_MODE_SMI) ||
+ (kvm->arch.init_sipi_unsupported &&
+ msg.arch_data.delivery_mode == APIC_DELIVERY_MODE_INIT) ||
(kvm->arch.x2apic_format && (msg.address_hi & 0xff));
}

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1573dddd1e43..f2b6a3f89e9e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4553,8 +4553,7 @@ static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu)

static int kvm_vcpu_ioctl_smi(struct kvm_vcpu *vcpu)
{
- /* TODO: use more precise flag */
- if (vcpu->arch.guest_state_protected)
+ if (vcpu->kvm->arch.smm_unsupported)
return -EINVAL;

kvm_make_request(KVM_REQ_SMI, vcpu);
--
2.25.1