redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

e1000: remove races when changing mtu

Browse source 
this patch fixes a bug that occurs when routing packets and simultaneously
changing the mtu.  the rx_buffer_len variable is used during the rx cleanup
and if that changes on the fly without stopping traffic bad things happen

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jesse Brandeburg 2009-09-25 12:19:02 +00:00 committed by David S. Miller
parent 8fce47317f
commit 3d6114e71d
1 changed files with 14 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
drivers/net/e1000/e1000_main.c
View file

@ -3141,6 +3141,13 @@ static int e1000_change_mtu(struct net_device *netdev, int new_mtu)
break;
}
while (test_and_set_bit(__E1000_RESETTING, &adapter->flags))
msleep(1);
/* e1000_down has a dependency on max_frame_size */
hw->max_frame_size = max_frame;
if (netif_running(netdev))
e1000_down(adapter);
/* NOTE: netdev_alloc_skb reserves 16 bytes, and typically NET_IP_ALIGN
* means we reserve 2 more, this pushes us to allocate from the next
* larger slab size.
@ -3169,11 +3176,16 @@ static int e1000_change_mtu(struct net_device *netdev, int new_mtu)
(max_frame == MAXIMUM_ETHERNET_VLAN_SIZE)))
adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
printk(KERN_INFO "e1000: %s changing MTU from %d to %d\n",
netdev->name, netdev->mtu, new_mtu);
netdev->mtu = new_mtu;
hw->max_frame_size = max_frame;
if (netif_running(netdev))
e1000_reinit_locked(adapter);
e1000_up(adapter);
else
e1000_reset(adapter);
clear_bit(__E1000_RESETTING, &adapter->flags);
return 0;
}