This is a note to let you know that I've just added the patch titled

    virtio-net: fix the race between channels setting and refill

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     virtio-net-fix-the-race-between-channels-setting-and-refill.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 451bad27ad7ce05114f03127a4ceca35d35d58a2 Mon Sep 17 00:00:00 2001
From: Jason Wang <[email protected]>
Date: Thu, 4 Jul 2013 11:22:57 +0930
Subject: virtio-net: fix the race between channels setting and refill

From: Jason Wang <[email protected]>

[ Upstream commit 9b9cd8024a2882e896c65222aa421d461354e3f2 ]

Commit 55257d72bd1c51f25106350f4983ec19f62ed1fa (virtio-net: fill only rx queues
which are being used) tries to refill on demand when changing the number of
channels by call try_refill_recv() directly, this may race:

- the refill work who may do the refill in the same time
- the try_refill_recv() called in bh since napi was not disabled

Which may led guest complain during setting channels:

virtio_net virtio0: input.1:id 0 is not a head!

Solve this issue by scheduling a refill work which can guarantee the
serialization of refill.

Signed-off-by: Jason Wang <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Michael S. Tsirkin <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/net/virtio_net.c |    5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -902,7 +902,6 @@ static int virtnet_set_queues(struct vir
        struct scatterlist sg;
        struct virtio_net_ctrl_mq s;
        struct net_device *dev = vi->dev;
-       int i;
 
        if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
                return 0;
@@ -916,10 +915,8 @@ static int virtnet_set_queues(struct vir
                         queue_pairs);
                return -EINVAL;
        } else {
-               for (i = vi->curr_queue_pairs; i < queue_pairs; i++)
-                       if (!try_fill_recv(&vi->rq[i], GFP_KERNEL))
-                               schedule_delayed_work(&vi->refill, 0);
                vi->curr_queue_pairs = queue_pairs;
+               schedule_delayed_work(&vi->refill, 0);
        }
 
        return 0;


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/virtio-net-fix-the-race-between-channels-setting-and-refill.patch
queue-3.10/virtio-net-refill-only-when-device-is-up-during-setting-queues.patch
queue-3.10/virtio-net-don-t-respond-to-cpu-hotplug-notifier-if-we-re-not-ready.patch
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