diff options
author | Jason Wang <jasowang@redhat.com> | 2013-06-05 03:40:46 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2013-06-10 17:31:45 -0400 |
commit | 4364d5f96eed7994a2c625bd9216656e55fba0cb (patch) | |
tree | 4106422c018c86f5b32a76299427ffacb6e45df1 /drivers/vhost | |
parent | d88210910a34b3b5da71e13fc53859516104e232 (diff) |
vhost_net: clear msg.control for non-zerocopy case during tx
When we decide not use zero-copy, msg.control should be set to NULL otherwise
macvtap/tap may set zerocopy callbacks which may decrease the kref of ubufs
wrongly.
Bug were introduced by commit cedb9bdce099206290a2bdd02ce47a7b253b6a84
(vhost-net: skip head management if no outstanding).
This solves the following warnings:
WARNING: at include/linux/kref.h:47 handle_tx+0x477/0x4b0 [vhost_net]()
Modules linked in: vhost_net macvtap macvlan tun nfsd exportfs bridge stp llc openvswitch kvm_amd kvm bnx2 megaraid_sas [last unloaded: tun]
CPU: 5 PID: 8670 Comm: vhost-8668 Not tainted 3.10.0-rc2+ #1566
Hardware name: Dell Inc. PowerEdge R715/00XHKG, BIOS 1.5.2 04/19/2011
ffffffffa0198323 ffff88007c9ebd08 ffffffff81796b73 ffff88007c9ebd48
ffffffff8103d66b 000000007b773e20 ffff8800779f0000 ffff8800779f43f0
ffff8800779f8418 000000000000015c 0000000000000062 ffff88007c9ebd58
Call Trace:
[<ffffffff81796b73>] dump_stack+0x19/0x1e
[<ffffffff8103d66b>] warn_slowpath_common+0x6b/0xa0
[<ffffffff8103d6b5>] warn_slowpath_null+0x15/0x20
[<ffffffffa0197627>] handle_tx+0x477/0x4b0 [vhost_net]
[<ffffffffa0197690>] handle_tx_kick+0x10/0x20 [vhost_net]
[<ffffffffa019541e>] vhost_worker+0xfe/0x1a0 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffff81061f46>] kthread+0xc6/0xd0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff817a1aec>] ret_from_fork+0x7c/0xb0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/vhost')
-rw-r--r-- | drivers/vhost/net.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 2b51e2336aa2..b07d96b8c0d1 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c | |||
@@ -436,7 +436,8 @@ static void handle_tx(struct vhost_net *net) | |||
436 | kref_get(&ubufs->kref); | 436 | kref_get(&ubufs->kref); |
437 | } | 437 | } |
438 | nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; | 438 | nvq->upend_idx = (nvq->upend_idx + 1) % UIO_MAXIOV; |
439 | } | 439 | } else |
440 | msg.msg_control = NULL; | ||
440 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ | 441 | /* TODO: Check specific error and bomb out unless ENOBUFS? */ |
441 | err = sock->ops->sendmsg(NULL, sock, &msg, len); | 442 | err = sock->ops->sendmsg(NULL, sock, &msg, len); |
442 | if (unlikely(err < 0)) { | 443 | if (unlikely(err < 0)) { |