kaweth: Fix locking to be SMP-safe

On an SMP system, the following message is printed. The patch below gets
fixes the problem.

=================================
[ INFO: inconsistent lock state ]
2.6.29-Linus-05093-gc31f403 #57
---------------------------------
inconsistent {hardirq-on-W} -> {in-hardirq-W} usage.
bash/4105 [HC1[1]:SC0[0]:HE0:SE1] takes:
 (&kaweth->device_lock){+...}, at: [<ffffffffa01aa286>]
                 kaweth_usb_receive+0x77/0x1af [kaw eth]
{hardirq-on-W} state was registered at:
  [<ffffffff80260503>] __lock_acquire+0x753/0x1685
  [<ffffffff8026148a>] lock_acquire+0x55/0x71
  [<ffffffff80461ba6>] _spin_lock+0x31/0x3d
  [<ffffffffa01aaa0c>] kaweth_start_xmit+0x2b/0x1e1 [kaweth]
  [<ffffffff803eccd3>] dev_hard_start_xmit+0x22e/0x2ad
  [<ffffffff803fe120>] __qdisc_run+0xf2/0x203
  [<ffffffff803ed0cd>] dev_queue_xmit+0x263/0x39b
  [<ffffffffa03a47cb>] packet_sendmsg_spkt+0x1c4/0x20a [af_packet]
  [<ffffffff803de0c2>] sock_sendmsg+0xe4/0xfd
  [<ffffffff803dec8f>] sys_sendto+0xe4/0x10c
  [<ffffffff8020bccb>] system_call_fastpath+0x16/0x1b
  [<ffffffffffffffff>] 0xffffffffffffffff
irq event stamp: 1280
hardirqs last  enabled at (1279): [<ffffffff80461a71>]
                  _spin_unlock_irqrestore+0x44/0x4c
hardirqs last disabled at (1280): [<ffffffff8020bad7>]
                  save_args+0x67/0x70
softirqs last  enabled at (660): [<ffffffff8024192c>]
                  __do_softirq+0x14d/0x15d
softirqs last disabled at (651): [<ffffffff8020ce9c>]
                  call_softirq+0x1c/0x28

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Larry Finger 2009-04-02 01:09:43 -07:00 committed by David S. Miller
parent f2bde73286
commit 4ff61c8f7b
1 changed files with 3 additions and 4 deletions

View File

@ -36,7 +36,6 @@
* Run test procedures
* Fix bugs from previous two steps
* Snoop other OSs for any tricks we're not doing
* SMP locking
* Reduce arbitrary timeouts
* Smart multicast support
* Temporary MAC change support
@ -796,7 +795,7 @@ static int kaweth_start_xmit(struct sk_buff *skb, struct net_device *net)
int res;
spin_lock(&kaweth->device_lock);
spin_lock_irq(&kaweth->device_lock);
kaweth_async_set_rx_mode(kaweth);
netif_stop_queue(net);
@ -814,7 +813,7 @@ static int kaweth_start_xmit(struct sk_buff *skb, struct net_device *net)
if (!copied_skb) {
kaweth->stats.tx_errors++;
netif_start_queue(net);
spin_unlock(&kaweth->device_lock);
spin_unlock_irq(&kaweth->device_lock);
return 0;
}
}
@ -848,7 +847,7 @@ skip:
net->trans_start = jiffies;
}
spin_unlock(&kaweth->device_lock);
spin_unlock_irq(&kaweth->device_lock);
return 0;
}