Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio fixes from Rusty Russell:
 "Not entirely surprising: the ongoing QEMU work on virtio 1.0 has
  revealed more minor issues with our virtio 1.0 drivers just introduced
  in the kernel.

  (I would normally use my fixes branch for this, but there were a batch
  of them...)"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_mmio: fix access width for mmio
  uapi/virtio_scsi: allow overriding CDB/SENSE size
  virtio_mmio: generation support
  virtio_rpmsg: set DRIVER_OK before using device
  9p/trans_virtio: fix hot-unplug
  virtio-balloon: do not call blocking ops when !TASK_RUNNING
  virtio_blk: fix comment for virtio 1.0
  virtio_blk: typo fix
  virtio_balloon: set DRIVER_OK before using device
  virtio_console: avoid config access from irq
  virtio_console: init work unconditionally

1 files changed, 20 insertions, 4 deletions

diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
index d8e376a5f0f1..36a1a739ad68 100644
--- a/net/9p/trans_virtio.c
+++ b/net/9p/trans_virtio.c
@@ -658,14 +658,30 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args)
 static void p9_virtio_remove(struct virtio_device *vdev)
 {
 	struct virtio_chan *chan = vdev->priv;
-
-	if (chan->inuse)
-		p9_virtio_close(chan->client);
-	vdev->config->del_vqs(vdev);
+	unsigned long warning_time;
 
 	mutex_lock(&virtio_9p_lock);
+
+	/* Remove self from list so we don't get new users. */
 	list_del(&chan->chan_list);
+	warning_time = jiffies;
+
+	/* Wait for existing users to close. */
+	while (chan->inuse) {
+		mutex_unlock(&virtio_9p_lock);
+		msleep(250);
+		if (time_after(jiffies, warning_time + 10 * HZ)) {
+			dev_emerg(&vdev->dev,
+				  "p9_virtio_remove: waiting for device in use.\n");
+			warning_time = jiffies;
+		}
+		mutex_lock(&virtio_9p_lock);
+	}
+
 	mutex_unlock(&virtio_9p_lock);
+
+	vdev->config->del_vqs(vdev);
+
 	sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr);
 	kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE);
 	kfree(chan->tag);