Re: [virtio-net] BUG: sleeping function called from invalid context at kernel/mutex.c:616

quoted

From 01e6c3f71c202aa02e4feda169e7cc9fb24193f5 Mon Sep 17 00:00:00 2001

From: Jason Wang <redacted>
Date: Mon, 21 Oct 2013 20:39:09 +0800
Subject: [PATCH] virtio-net: fix

---
 drivers/net/virtio_net.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9fbdfcd..bbc9cb8 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c

@@ -1118,11 +1118,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb,
 {
 	struct virtnet_info *vi = container_of(nfb, struct virtnet_info, nb);
 
-	mutex_lock(&vi->config_lock);
-
-	if (!vi->config_enable)
-		goto done;
-
 	switch(action & ~CPU_TASKS_FROZEN) {
 	case CPU_ONLINE:
 	case CPU_DOWN_FAILED:

@@ -1136,8 +1131,6 @@ static int virtnet_cpu_callback(struct notifier_block *nfb,
 		break;
 	}
 
-done:
-	mutex_unlock(&vi->config_lock);
 	return NOTIFY_OK;
 }
 

@@ -1699,6 +1692,8 @@ static int virtnet_freeze(struct virtio_device *vdev)
 	struct virtnet_info *vi = vdev->priv;
 	int i;
 
+	unregister_hotcpu_notifier(&vi->nb);
+
 	/* Prevent config work handler from accessing the device */
 	mutex_lock(&vi->config_lock);
 	vi->config_enable = false;

@@ -1747,6 +1742,10 @@ static int virtnet_restore(struct virtio_device *vdev)
 	virtnet_set_queues(vi, vi->curr_queue_pairs);
 	rtnl_unlock();
 
+	err = register_hotcpu_notifier(&vi->nb);
+	if (err)
+		return err;
+
 	return 0;
 }
 #endif

-- 
1.8.1.2