From cd7764fe9f73530b20a0f2310fa753af635fabb3 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Thu, 4 Jun 2015 10:41:21 +0200
Subject: [PATCH] KVM: x86: latch INITs while in system management mode
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Do not process INITs immediately while in system management mode, keep
it instead in apic->pending_events. Tell userspace if an INIT is
pending when they issue GET_VCPU_EVENTS, and similarly handle the
new field in SET_VCPU_EVENTS.
Note that the same treatment should be done while in VMX non-root mode.
Reviewed-by: Radim KrÄmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/lapic.c | 13 ++++++++++++-
arch/x86/kvm/x86.c | 3 +++
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index b8e47e2b1d941..beeef05bb4d9b 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2057,8 +2057,19 @@ void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
return;
- pe = xchg(&apic->pending_events, 0);
+ /*
+ * INITs are latched while in SMM. Because an SMM CPU cannot
+ * be in KVM_MP_STATE_INIT_RECEIVED state, just eat SIPIs
+ * and delay processing of INIT until the next RSM.
+ */
+ if (is_smm(vcpu)) {
+ WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED);
+ if (test_bit(KVM_APIC_SIPI, &apic->pending_events))
+ clear_bit(KVM_APIC_SIPI, &apic->pending_events);
+ return;
+ }
+ pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
kvm_lapic_reset(vcpu, true);
kvm_vcpu_reset(vcpu, true);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ab977e763812f..ab2521b588d87 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5482,6 +5482,9 @@ static void kvm_smm_changed(struct kvm_vcpu *vcpu)
if (unlikely(vcpu->arch.smi_pending)) {
kvm_make_request(KVM_REQ_SMI, vcpu);
vcpu->arch.smi_pending = 0;
+ } else {
+ /* Process a latched INIT, if any. */
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
}
}
}
--
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