This is a note to let you know that I've just added the patch titled
KVM: x86: fix vcpu initialization with userspace lapic
to the 4.14-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-fix-vcpu-initialization-with-userspace-lapic.patch and it can be found in the queue-4.14 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 b7e31be385584afe7f073130e8e570d53c95f7fe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= rkrcmar@redhat.com Date: Thu, 1 Mar 2018 15:24:25 +0100 Subject: KVM: x86: fix vcpu initialization with userspace lapic MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
From: Radim Krčmář rkrcmar@redhat.com
commit b7e31be385584afe7f073130e8e570d53c95f7fe upstream.
Moving the code around broke this rare configuration. Use this opportunity to finally call lapic reset from vcpu reset.
Reported-by: syzbot+fb7a33a4b6c35007a72b@syzkaller.appspotmail.com Suggested-by: Paolo Bonzini pbonzini@redhat.com Fixes: 0b2e9904c159 ("KVM: x86: move LAPIC initialization after VMCS creation") Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář rkrcmar@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kvm/lapic.c | 10 ++++------ arch/x86/kvm/x86.c | 3 ++- 2 files changed, 6 insertions(+), 7 deletions(-)
--- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1944,14 +1944,13 @@ void kvm_lapic_set_base(struct kvm_vcpu
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); @@ -2510,7 +2509,6 @@ void kvm_apic_accept_events(struct kvm_v
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; --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7779,7 +7779,6 @@ 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; @@ -7822,6 +7821,8 @@ void kvm_arch_vcpu_destroy(struct kvm_vc
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;
Patches currently in stable-queue which might be from rkrcmar@redhat.com are
queue-4.14/kvm-x86-fix-smram-accessing-even-if-vm-is-shutdown.patch queue-4.14/kvm-x86-remove-indirect-msr-op-calls-from-spec_ctrl.patch queue-4.14/kvm-mmu-fix-overlap-between-public-and-private-memslots.patch queue-4.14/kvm-x86-fix-vcpu-initialization-with-userspace-lapic.patch queue-4.14/kvm-vmx-optimize-vmx_vcpu_run-and-svm_vcpu_run-by-marking-the-rdmsr-path-as-unlikely.patch