1 files changed, 135 insertions, 12 deletions

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index a43e1cb3b7e9..95b715cdf6f3 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -128,6 +128,16 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
 	int ret;
 
+	mutex_init(&kvm->arch.config_lock);
+
+#ifdef CONFIG_LOCKDEP
+	/* Clue in lockdep that the config_lock must be taken inside kvm->lock */
+	mutex_lock(&kvm->lock);
+	mutex_lock(&kvm->arch.config_lock);
+	mutex_unlock(&kvm->arch.config_lock);
+	mutex_unlock(&kvm->lock);
+#endif
+
 	ret = kvm_share_hyp(kvm, kvm + 1);
 	if (ret)
 		return ret;
@@ -148,6 +158,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 
 	kvm_vgic_early_init(kvm);
 
+	kvm_timer_init_vm(kvm);
+
 	/* The maximum number of VCPUs is limited by the host's GIC model */
 	kvm->max_vcpus = kvm_arm_default_max_vcpus();
 
@@ -192,6 +204,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	kvm_destroy_vcpus(kvm);
 
 	kvm_unshare_hyp(kvm, kvm + 1);
+
+	kvm_arm_teardown_hypercalls(kvm);
 }
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
@@ -220,6 +234,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_VCPU_ATTRIBUTES:
 	case KVM_CAP_PTP_KVM:
 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
+	case KVM_CAP_COUNTER_OFFSET:
 		r = 1;
 		break;
 	case KVM_CAP_SET_GUEST_DEBUG2:
@@ -326,6 +341,16 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
 	int err;
 
+	spin_lock_init(&vcpu->arch.mp_state_lock);
+
+#ifdef CONFIG_LOCKDEP
+	/* Inform lockdep that the config_lock is acquired after vcpu->mutex */
+	mutex_lock(&vcpu->mutex);
+	mutex_lock(&vcpu->kvm->arch.config_lock);
+	mutex_unlock(&vcpu->kvm->arch.config_lock);
+	mutex_unlock(&vcpu->mutex);
+#endif
+
 	/* Force users to call KVM_ARM_VCPU_INIT */
 	vcpu->arch.target = -1;
 	bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
@@ -443,34 +468,41 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 	vcpu->cpu = -1;
 }
 
-void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
+static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
 {
-	vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED;
+	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
 	kvm_vcpu_kick(vcpu);
 }
 
+void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
+{
+	spin_lock(&vcpu->arch.mp_state_lock);
+	__kvm_arm_vcpu_power_off(vcpu);
+	spin_unlock(&vcpu->arch.mp_state_lock);
+}
+
 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
 {
-	return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED;
+	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
 }
 
 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
 {
-	vcpu->arch.mp_state.mp_state = KVM_MP_STATE_SUSPENDED;
+	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
 	kvm_vcpu_kick(vcpu);
 }
 
 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
 {
-	return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_SUSPENDED;
+	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
 }
 
 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 				    struct kvm_mp_state *mp_state)
 {
-	*mp_state = vcpu->arch.mp_state;
+	*mp_state = READ_ONCE(vcpu->arch.mp_state);
 
 	return 0;
 }
@@ -480,12 +512,14 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 {
 	int ret = 0;
 
+	spin_lock(&vcpu->arch.mp_state_lock);
+
 	switch (mp_state->mp_state) {
 	case KVM_MP_STATE_RUNNABLE:
-		vcpu->arch.mp_state = *mp_state;
+		WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
 		break;
 	case KVM_MP_STATE_STOPPED:
-		kvm_arm_vcpu_power_off(vcpu);
+		__kvm_arm_vcpu_power_off(vcpu);
 		break;
 	case KVM_MP_STATE_SUSPENDED:
 		kvm_arm_vcpu_suspend(vcpu);
@@ -494,6 +528,8 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 		ret = -EINVAL;
 	}
 
+	spin_unlock(&vcpu->arch.mp_state_lock);
+
 	return ret;
 }
 
@@ -593,9 +629,9 @@ int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
 	if (kvm_vm_is_protected(kvm))
 		kvm_call_hyp_nvhe(__pkvm_vcpu_init_traps, vcpu);
 
-	mutex_lock(&kvm->lock);
+	mutex_lock(&kvm->arch.config_lock);
 	set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
-	mutex_unlock(&kvm->lock);
+	mutex_unlock(&kvm->arch.config_lock);
 
 	return ret;
 }
@@ -1210,10 +1246,14 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
 	/*
 	 * Handle the "start in power-off" case.
 	 */
+	spin_lock(&vcpu->arch.mp_state_lock);
+
 	if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
-		kvm_arm_vcpu_power_off(vcpu);
+		__kvm_arm_vcpu_power_off(vcpu);
 	else
-		vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE;
+		WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
+
+	spin_unlock(&vcpu->arch.mp_state_lock);
 
 	return 0;
 }
@@ -1439,10 +1479,31 @@ static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
 	}
 }
 
+static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	switch (attr->group) {
+	case KVM_ARM_VM_SMCCC_CTRL:
+		return kvm_vm_smccc_has_attr(kvm, attr);
+	default:
+		return -ENXIO;
+	}
+}
+
+static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
+{
+	switch (attr->group) {
+	case KVM_ARM_VM_SMCCC_CTRL:
+		return kvm_vm_smccc_set_attr(kvm, attr);
+	default:
+		return -ENXIO;
+	}
+}
+
 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 {
 	struct kvm *kvm = filp->private_data;
 	void __user *argp = (void __user *)arg;
+	struct kvm_device_attr attr;
 
 	switch (ioctl) {
 	case KVM_CREATE_IRQCHIP: {
@@ -1478,11 +1539,73 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 			return -EFAULT;
 		return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
 	}
+	case KVM_ARM_SET_COUNTER_OFFSET: {
+		struct kvm_arm_counter_offset offset;
+
+		if (copy_from_user(&offset, argp, sizeof(offset)))
+			return -EFAULT;
+		return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
+	}
+	case KVM_HAS_DEVICE_ATTR: {
+		if (copy_from_user(&attr, argp, sizeof(attr)))
+			return -EFAULT;
+
+		return kvm_vm_has_attr(kvm, &attr);
+	}
+	case KVM_SET_DEVICE_ATTR: {
+		if (copy_from_user(&attr, argp, sizeof(attr)))
+			return -EFAULT;
+
+		return kvm_vm_set_attr(kvm, &attr);
+	}
 	default:
 		return -EINVAL;
 	}
 }
 
+/* unlocks vcpus from @vcpu_lock_idx and smaller */
+static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
+{
+	struct kvm_vcpu *tmp_vcpu;
+
+	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
+		tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
+		mutex_unlock(&tmp_vcpu->mutex);
+	}
+}
+
+void unlock_all_vcpus(struct kvm *kvm)
+{
+	lockdep_assert_held(&kvm->lock);
+
+	unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
+}
+
+/* Returns true if all vcpus were locked, false otherwise */
+bool lock_all_vcpus(struct kvm *kvm)
+{
+	struct kvm_vcpu *tmp_vcpu;
+	unsigned long c;
+
+	lockdep_assert_held(&kvm->lock);
+
+	/*
+	 * Any time a vcpu is in an ioctl (including running), the
+	 * core KVM code tries to grab the vcpu->mutex.
+	 *
+	 * By grabbing the vcpu->mutex of all VCPUs we ensure that no
+	 * other VCPUs can fiddle with the state while we access it.
+	 */
+	kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
+		if (!mutex_trylock(&tmp_vcpu->mutex)) {
+			unlock_vcpus(kvm, c - 1);
+			return false;
+		}
+	}
+
+	return true;
+}
+
 static unsigned long nvhe_percpu_size(void)
 {
 	return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -