diff options
| -rw-r--r-- | arch/arm64/kvm/vgic/vgic-init.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index e7c53e8af3d1..57aedf7b2b76 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -417,8 +417,28 @@ static void __kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) kfree(vgic_cpu->private_irqs); vgic_cpu->private_irqs = NULL; - if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) + if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) { + /* + * If this vCPU is being destroyed because of a failed creation + * then unregister the redistributor to avoid leaving behind a + * dangling pointer to the vCPU struct. + * + * vCPUs that have been successfully created (i.e. added to + * kvm->vcpu_array) get unregistered in kvm_vgic_destroy(), as + * this function gets called while holding kvm->arch.config_lock + * in the VM teardown path and would otherwise introduce a lock + * inversion w.r.t. kvm->srcu. + * + * vCPUs that failed creation are torn down outside of the + * kvm->arch.config_lock and do not get unregistered in + * kvm_vgic_destroy(), meaning it is both safe and necessary to + * do so here. + */ + if (kvm_get_vcpu_by_id(vcpu->kvm, vcpu->vcpu_id) != vcpu) + vgic_unregister_redist_iodev(vcpu); + vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF; + } } void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) |