[net-next-2.6 PATCH] 8021q: vlan device is lockless do not transfer real_num_{tx|rx}_queues

[net-next-2.6 PATCH] 8021q: vlan device is lockless do not transfer real_num_{tx|rx}_queues

[John Fastabend]

Now that the vlan device is lockless and single queue do not
transfer the real num queues. This is causing a BUG_ON to occur.

kernel BUG at net/8021q/vlan.c:345!
Call Trace:
[<ffffffff813fd6e8>] ? fib_rules_event+0x28/0x1b0
[<ffffffff814ad2b5>] notifier_call_chain+0x55/0x80
[<ffffffff81089156>] raw_notifier_call_chain+0x16/0x20
[<ffffffff813e5af7>] call_netdevice_notifiers+0x37/0x70
[<ffffffff813e6756>] netdev_features_change+0x16/0x20
[<ffffffffa02995be>] ixgbe_fcoe_enable+0xae/0x100 [ixgbe]
[<ffffffffa01da06a>] vlan_dev_fcoe_enable+0x2a/0x30 [8021q]
[<ffffffffa02d08c3>] fcoe_create+0x163/0x630 [fcoe]
[<ffffffff811244d5>] ? mmap_region+0x255/0x5a0
[<ffffffff81080ef0>] param_attr_store+0x50/0x80
[<ffffffff810809b6>] module_attr_store+0x26/0x30
[<ffffffff811b9db2>] sysfs_write_file+0xf2/0x180
[<ffffffff8114fc88>] vfs_write+0xc8/0x190
[<ffffffff81150621>] sys_write+0x51/0x90
[<ffffffff8100c0b2>] system_call_fastpath+0x16/0x1b

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
---

 net/8021q/vlan.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index dc10713..6e64f7c 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -341,9 +341,6 @@ static void vlan_transfer_features(struct net_device *dev,
 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
 	vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
 #endif
-	vlandev->real_num_tx_queues = dev->real_num_tx_queues;
-	BUG_ON(vlandev->real_num_tx_queues > vlandev->num_tx_queues);
-
 	if (old_features != vlandev->features)
 		netdev_features_change(vlandev);
 }

Re: [net-next-2.6 PATCH] 8021q: vlan device is lockless do not transfer real_num_{tx|rx}_queues

[David Miller]

From: John Fastabend <john.r.fastabend@intel.com>
Date: Wed, 24 Nov 2010 15:14:50 -0800

> Now that the vlan device is lockless and single queue do not
> transfer the real num queues. This is causing a BUG_ON to occur.
> 
> kernel BUG at net/8021q/vlan.c:345!
> Call Trace:
> [<ffffffff813fd6e8>] ? fib_rules_event+0x28/0x1b0
> [<ffffffff814ad2b5>] notifier_call_chain+0x55/0x80
> [<ffffffff81089156>] raw_notifier_call_chain+0x16/0x20
> [<ffffffff813e5af7>] call_netdevice_notifiers+0x37/0x70
> [<ffffffff813e6756>] netdev_features_change+0x16/0x20
> [<ffffffffa02995be>] ixgbe_fcoe_enable+0xae/0x100 [ixgbe]
> [<ffffffffa01da06a>] vlan_dev_fcoe_enable+0x2a/0x30 [8021q]
> [<ffffffffa02d08c3>] fcoe_create+0x163/0x630 [fcoe]
> [<ffffffff811244d5>] ? mmap_region+0x255/0x5a0
> [<ffffffff81080ef0>] param_attr_store+0x50/0x80
> [<ffffffff810809b6>] module_attr_store+0x26/0x30
> [<ffffffff811b9db2>] sysfs_write_file+0xf2/0x180
> [<ffffffff8114fc88>] vfs_write+0xc8/0x190
> [<ffffffff81150621>] sys_write+0x51/0x90
> [<ffffffff8100c0b2>] system_call_fastpath+0x16/0x1b
> 
> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>

Applied.