Re: [RFC PATCH v5 070/104] KVM: TDX: complete interrupts after tdexit

From: Paolo Bonzini
Date: Fri Apr 15 2022 - 10:07:37 EST


On 3/4/22 20:49, isaku.yamahata@xxxxxxxxx wrote:
From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

This corresponds to VMX __vmx_complete_interrupts(). Because TDX
virtualize vAPIC, KVM only needs to care NMI injection.

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/kvm/vmx/tdx.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index c1366aac7d96..3cb2fbd1c12c 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -550,6 +550,14 @@ void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vcpu->kvm->vm_bugged = true;
}
+static void tdx_complete_interrupts(struct kvm_vcpu *vcpu)
+{
+ /* Avoid costly SEAMCALL if no nmi was injected */
+ if (vcpu->arch.nmi_injected)
+ vcpu->arch.nmi_injected = td_management_read8(to_tdx(vcpu),
+ TD_VCPU_PEND_NMI);
+}
+
struct tdx_uret_msr {
u32 msr;
unsigned int slot;
@@ -618,6 +626,8 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu)
vcpu->arch.regs_avail &= ~VMX_REGS_LAZY_LOAD_SET;
trace_kvm_exit(vcpu, KVM_ISA_VMX);
+ tdx_complete_interrupts(vcpu);
+
if (tdx->exit_reason.error || tdx->exit_reason.non_recoverable)
return EXIT_FASTPATH_NONE;
return EXIT_FASTPATH_NONE;

Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>