Merge branch 'for-next' into for-linus

1 files changed, 17 insertions, 9 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 45d4b8182b07..bc491a73815c 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1207,6 +1207,8 @@ static int kvm_s390_vm_get_migration(struct kvm *kvm,
 	return 0;
 }
 
+static void __kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod);
+
 static int kvm_s390_set_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
 {
 	struct kvm_s390_vm_tod_clock gtod;
@@ -1216,7 +1218,7 @@ static int kvm_s390_set_tod_ext(struct kvm *kvm, struct kvm_device_attr *attr)
 
 	if (!test_kvm_facility(kvm, 139) && gtod.epoch_idx)
 		return -EINVAL;
-	kvm_s390_set_tod_clock(kvm, &gtod);
+	__kvm_s390_set_tod_clock(kvm, &gtod);
 
 	VM_EVENT(kvm, 3, "SET: TOD extension: 0x%x, TOD base: 0x%llx",
 		gtod.epoch_idx, gtod.tod);
@@ -1247,7 +1249,7 @@ static int kvm_s390_set_tod_low(struct kvm *kvm, struct kvm_device_attr *attr)
 			   sizeof(gtod.tod)))
 		return -EFAULT;
 
-	kvm_s390_set_tod_clock(kvm, &gtod);
+	__kvm_s390_set_tod_clock(kvm, &gtod);
 	VM_EVENT(kvm, 3, "SET: TOD base: 0x%llx", gtod.tod);
 	return 0;
 }
@@ -1259,6 +1261,16 @@ static int kvm_s390_set_tod(struct kvm *kvm, struct kvm_device_attr *attr)
 	if (attr->flags)
 		return -EINVAL;
 
+	mutex_lock(&kvm->lock);
+	/*
+	 * For protected guests, the TOD is managed by the ultravisor, so trying
+	 * to change it will never bring the expected results.
+	 */
+	if (kvm_s390_pv_is_protected(kvm)) {
+		ret = -EOPNOTSUPP;
+		goto out_unlock;
+	}
+
 	switch (attr->attr) {
 	case KVM_S390_VM_TOD_EXT:
 		ret = kvm_s390_set_tod_ext(kvm, attr);
@@ -1273,6 +1285,9 @@ static int kvm_s390_set_tod(struct kvm *kvm, struct kvm_device_attr *attr)
 		ret = -ENXIO;
 		break;
 	}
+
+out_unlock:
+	mutex_unlock(&kvm->lock);
 	return ret;
 }
 
@@ -4377,13 +4392,6 @@ static void __kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_t
 	preempt_enable();
 }
 
-void kvm_s390_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod)
-{
-	mutex_lock(&kvm->lock);
-	__kvm_s390_set_tod_clock(kvm, gtod);
-	mutex_unlock(&kvm->lock);
-}
-
 int kvm_s390_try_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clock *gtod)
 {
 	if (!mutex_trylock(&kvm->lock))