--- zzzz-none-000/linux-3.10.107/drivers/vhost/test.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/vhost/test.c	2021-02-04 17:41:59.000000000 +0000
@@ -13,12 +13,11 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/workqueue.h>
-#include <linux/rcupdate.h>
 #include <linux/file.h>
 #include <linux/slab.h>
 
 #include "test.h"
-#include "vhost.c"
+#include "vhost.h"
 
 /* Max number of bytes transferred before requeueing the job.
  * Using this limit prevents one virtqueue from starving others. */
@@ -38,21 +37,23 @@
  * read-size critical section for our kind of RCU. */
 static void handle_vq(struct vhost_test *n)
 {
-	struct vhost_virtqueue *vq = &n->dev.vqs[VHOST_TEST_VQ];
+	struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
 	unsigned out, in;
 	int head;
 	size_t len, total_len = 0;
 	void *private;
 
-	private = rcu_dereference_check(vq->private_data, 1);
-	if (!private)
+	mutex_lock(&vq->mutex);
+	private = vq->private_data;
+	if (!private) {
+		mutex_unlock(&vq->mutex);
 		return;
+	}
 
-	mutex_lock(&vq->mutex);
 	vhost_disable_notify(&n->dev, vq);
 
 	for (;;) {
-		head = vhost_get_vq_desc(&n->dev, vq, vq->iov,
+		head = vhost_get_vq_desc(vq, vq->iov,
 					 ARRAY_SIZE(vq->iov),
 					 &out, &in,
 					 NULL, NULL);
@@ -102,18 +103,20 @@
 {
 	struct vhost_test *n = kmalloc(sizeof *n, GFP_KERNEL);
 	struct vhost_dev *dev;
-	int r;
+	struct vhost_virtqueue **vqs;
 
 	if (!n)
 		return -ENOMEM;
+	vqs = kmalloc(VHOST_TEST_VQ_MAX * sizeof(*vqs), GFP_KERNEL);
+	if (!vqs) {
+		kfree(n);
+		return -ENOMEM;
+	}
 
 	dev = &n->dev;
+	vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ];
 	n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick;
-	r = vhost_dev_init(dev, n->vqs, VHOST_TEST_VQ_MAX);
-	if (r < 0) {
-		kfree(n);
-		return r;
-	}
+	vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX);
 
 	f->private_data = n;
 
@@ -126,9 +129,8 @@
 	void *private;
 
 	mutex_lock(&vq->mutex);
-	private = rcu_dereference_protected(vq->private_data,
-					 lockdep_is_held(&vq->mutex));
-	rcu_assign_pointer(vq->private_data, NULL);
+	private = vq->private_data;
+	vq->private_data = NULL;
 	mutex_unlock(&vq->mutex);
 	return private;
 }
@@ -140,7 +142,7 @@
 
 static void vhost_test_flush_vq(struct vhost_test *n, int index)
 {
-	vhost_poll_flush(&n->dev.vqs[index].poll);
+	vhost_poll_flush(&n->vqs[index].poll);
 }
 
 static void vhost_test_flush(struct vhost_test *n)
@@ -191,9 +193,8 @@
 		priv = test ? n : NULL;
 
 		/* start polling new socket */
-		oldpriv = rcu_dereference_protected(vq->private_data,
-						    lockdep_is_held(&vq->mutex));
-		rcu_assign_pointer(vq->private_data, priv);
+		oldpriv = vq->private_data;
+		vq->private_data = priv;
 
 		r = vhost_init_used(&n->vqs[index]);
 
@@ -240,15 +241,18 @@
 
 static int vhost_test_set_features(struct vhost_test *n, u64 features)
 {
+	struct vhost_virtqueue *vq;
+
 	mutex_lock(&n->dev.mutex);
 	if ((features & (1 << VHOST_F_LOG_ALL)) &&
 	    !vhost_log_access_ok(&n->dev)) {
 		mutex_unlock(&n->dev.mutex);
 		return -EFAULT;
 	}
-	n->dev.acked_features = features;
-	smp_wmb();
-	vhost_test_flush(n);
+	vq = &n->vqs[VHOST_TEST_VQ];
+	mutex_lock(&vq->mutex);
+	vq->acked_features = features;
+	mutex_unlock(&vq->mutex);
 	mutex_unlock(&n->dev.mutex);
 	return 0;
 }
@@ -268,15 +272,18 @@
 			return -EFAULT;
 		return vhost_test_run(n, test);
 	case VHOST_GET_FEATURES:
-		features = VHOST_NET_FEATURES;
+		features = VHOST_FEATURES;
 		if (copy_to_user(featurep, &features, sizeof features))
 			return -EFAULT;
 		return 0;
 	case VHOST_SET_FEATURES:
+		printk(KERN_ERR "1\n");
 		if (copy_from_user(&features, featurep, sizeof features))
 			return -EFAULT;
-		if (features & ~VHOST_NET_FEATURES)
+		printk(KERN_ERR "2\n");
+		if (features & ~VHOST_FEATURES)
 			return -EOPNOTSUPP;
+		printk(KERN_ERR "3\n");
 		return vhost_test_set_features(n, features);
 	case VHOST_RESET_OWNER:
 		return vhost_test_reset_owner(n);