This is a note to let you know that I've just added the patch titled
KVM: x86: move LAPIC initialization after VMCS creation
to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: kvm-x86-move-lapic-initialization-after-vmcs-creation.patch and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 0b2e9904c15963e715d33e5f3f1387f17d19333a Mon Sep 17 00:00:00 2001
From: Paolo Bonzini pbonzini@redhat.com Date: Fri, 23 Feb 2018 23:29:32 +0100 Subject: KVM: x86: move LAPIC initialization after VMCS creation
From: Paolo Bonzini pbonzini@redhat.com
commit 0b2e9904c15963e715d33e5f3f1387f17d19333a upstream.
The initial reset of the local APIC is performed before the VMCS has been created, but it tries to do a vmwrite:
vmwrite error: reg 810 value 4a00 (err 18944) CPU: 54 PID: 38652 Comm: qemu-kvm Tainted: G W I 4.16.0-0.rc2.git0.1.fc28.x86_64 #1 Hardware name: Intel Corporation S2600CW/S2600CW, BIOS SE5C610.86B.01.01.0003.090520141303 09/05/2014 Call Trace: vmx_set_rvi [kvm_intel] vmx_hwapic_irr_update [kvm_intel] kvm_lapic_reset [kvm] kvm_create_lapic [kvm] kvm_arch_vcpu_init [kvm] kvm_vcpu_init [kvm] vmx_create_vcpu [kvm_intel] kvm_vm_ioctl [kvm]
Move it later, after the VMCS has been created.
Fixes: 4191db26b714 ("KVM: x86: Update APICv on APIC reset") Cc: stable@vger.kernel.org Cc: Liran Alon liran.alon@oracle.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/lapic.c | 1 - arch/x86/kvm/x86.c | 1 + 2 files changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2156,7 +2156,6 @@ int kvm_create_lapic(struct kvm_vcpu *vc */ vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE; static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */ - kvm_lapic_reset(vcpu, false); kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
return 0; --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7793,6 +7793,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu if (r) return r; kvm_vcpu_reset(vcpu, false); + kvm_lapic_reset(vcpu, false); kvm_mmu_setup(vcpu); vcpu_put(vcpu); return r;
Patches currently in stable-queue which might be from pbonzini@redhat.com are
queue-4.15/kvm-x86-fix-smram-accessing-even-if-vm-is-shutdown.patch queue-4.15/kvm-x86-remove-indirect-msr-op-calls-from-spec_ctrl.patch queue-4.15/kvm-x86-move-lapic-initialization-after-vmcs-creation.patch queue-4.15/kvm-mmu-fix-overlap-between-public-and-private-memslots.patch queue-4.15/kvm-vmx-optimize-vmx_vcpu_run-and-svm_vcpu_run-by-marking-the-rdmsr-path-as-unlikely.patch