[PATCH 4.19 73/97] KVM: nVMX: handle nested posted interrupts when apicv is disabled for L1

Greg Kroah-Hartman
2020-02-27T14:05:31Z

From: Vitaly Kuznetsov <vkuznets@redhat.com>

commit 91a5f413af596ad01097e59bf487eb07cb3f1331 upstream.

Even when APICv is disabled for L1 it can (and, actually, is) still
available for L2, this means we need to always call
vmx_deliver_nested_posted_interrupt() when attempting an interrupt
delivery.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/lapic.c | 5 +----
arch/x86/kvm/svm.c | 7 ++++++-
arch/x86/kvm/vmx.c | 13 +++++++++----
4 files changed, 17 insertions(+), 10 deletions(-)

--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1040,7 +1040,7 @@ struct kvm_x86_ops {
void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
void (*set_virtual_apic_mode)(struct kvm_vcpu *vcpu);
void (*set_apic_access_page_addr)(struct kvm_vcpu *vcpu, hpa_t hpa);
- void (*deliver_posted_interrupt)(struct kvm_vcpu *vcpu, int vector);
+ int (*deliver_posted_interrupt)(struct kvm_vcpu *vcpu, int vector);
int (*sync_pir_to_irr)(struct kvm_vcpu *vcpu);
int (*set_tss_addr)(struct kvm *kvm, unsigned int addr);
int (*set_identity_map_addr)(struct kvm *kvm, u64 ident_addr);
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1060,11 +1060,8 @@ static int __apic_accept_irq(struct kvm_
apic_clear_vector(vector, apic->regs + APIC_TMR);
}

- if (vcpu->arch.apicv_active)
- kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
- else {
+ if (kvm_x86_ops->deliver_posted_interrupt(vcpu, vector)) {
kvm_lapic_set_irr(vector, apic);
-
kvm_make_request(KVM_REQ_EVENT, vcpu);
kvm_vcpu_kick(vcpu);
}
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -5140,8 +5140,11 @@ static void svm_load_eoi_exitmap(struct
return;
}

-static void svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
+static int svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
{
+ if (!vcpu->arch.apicv_active)
+ return -1;
+
kvm_lapic_set_irr(vec, vcpu->arch.apic);
smp_mb__after_atomic();

@@ -5150,6 +5153,8 @@ static void svm_deliver_avic_intr(struct
kvm_cpu_get_apicid(vcpu->cpu));
else
kvm_vcpu_wake_up(vcpu);
+
+ return 0;
}

static bool svm_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6284,24 +6284,29 @@ static int vmx_deliver_nested_posted_int
* 2. If target vcpu isn't running(root mode), kick it to pick up the
* interrupt from PIR in next vmentry.
*/
-static void vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
+static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
int r;

r = vmx_deliver_nested_posted_interrupt(vcpu, vector);
if (!r)
- return;
+ return 0;
+
+ if (!vcpu->arch.apicv_active)
+ return -1;

if (pi_test_and_set_pir(vector, &vmx->pi_desc))
- return;
+ return 0;

/* If a previous notification has sent the IPI, nothing to do. */
if (pi_test_and_set_on(&vmx->pi_desc))
- return;
+ return 0;

if (!kvm_vcpu_trigger_posted_interrupt(vcpu, false))
kvm_vcpu_kick(vcpu);
+
+ return 0;
}

/*