The patch below does not apply to the 4.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b7e31be385584afe7f073130e8e570d53c95f7fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= <rkrcmar@xxxxxxxxxx>
Date: Thu, 1 Mar 2018 15:24:25 +0100
Subject: [PATCH] KVM: x86: fix vcpu initialization with userspace lapic
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Moving the code around broke this rare configuration.
Use this opportunity to finally call lapic reset from vcpu reset.
Reported-by: syzbot+fb7a33a4b6c35007a72b@xxxxxxxxxxxxxxxxxxxxxxxxx
Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Fixes: 0b2e9904c159 ("KVM: x86: move LAPIC initialization after VMCS creation")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index cc5fe7a50dde..391dda8d43b7 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2002,14 +2002,13 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
{
- struct kvm_lapic *apic;
+ struct kvm_lapic *apic = vcpu->arch.apic;
int i;
- apic_debug("%s\n", __func__);
+ if (!apic)
+ return;
- ASSERT(vcpu);
- apic = vcpu->arch.apic;
- ASSERT(apic != NULL);
+ apic_debug("%s\n", __func__);
/* Stop the timer in case it's a reset to an active apic */
hrtimer_cancel(&apic->lapic_timer.timer);
@@ -2568,7 +2567,6 @@ void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
pe = xchg(&apic->pending_events, 0);
if (test_bit(KVM_APIC_INIT, &pe)) {
- kvm_lapic_reset(vcpu, true);
kvm_vcpu_reset(vcpu, true);
if (kvm_vcpu_is_bsp(apic->vcpu))
vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 11649d290b93..18b5ca7a3197 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8060,7 +8060,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
kvm_vcpu_mtrr_init(vcpu);
vcpu_load(vcpu);
kvm_vcpu_reset(vcpu, false);
- kvm_lapic_reset(vcpu, false);
kvm_mmu_setup(vcpu);
vcpu_put(vcpu);
return 0;
@@ -8103,6 +8102,8 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
+ kvm_lapic_reset(vcpu, init_event);
+
vcpu->arch.hflags = 0;
vcpu->arch.smi_pending = 0;