Hi Andrew, Jeff,
The iseries_veth driver is badly behaved in that it will keep TX packets
hanging around forever if they're not ACK'ed and the queue never fills up.
This causes the unregister_netdevice code to wait forever when we try to take
the device down, because there's still skbs around with references to our
struct net_device.
There's already code to cleanup any un-ACK'ed packets in veth_stop_connection()
but it's being called after we unregister the net_device, which is too late.
The fix is to rearrange the module exit function so that we cleanup any
outstanding skbs and then unregister the driver.
Signed-off-by: Michael Ellerman <michael@xxxxxxxxxxxxxx>
--
drivers/net/iseries_veth.c | 11 +++++++++--
1 files changed, 9 insertions(+), 2 deletions(-)
Index: veth-fixes/drivers/net/iseries_veth.c
===================================================================
--- veth-fixes.orig/drivers/net/iseries_veth.c 2005-05-12 16:27:32.000000000
+1000
+++ veth-fixes/drivers/net/iseries_veth.c 2005-05-12 16:27:42.000000000
+1000
@@ -1388,18 +1388,25 @@
{
int i;
- vio_unregister_driver(&veth_driver);
+ /* Stop the queues first to stop any new packets being sent. */
+ for (i = 0; i < HVMAXARCHITECTEDVIRTUALLANS; i++)
+ if (veth_dev[i])
+ netif_stop_queue(veth_dev[i]);
+ /* Stop the connections before we unregister the driver. This
+ * ensures there's no skbs lying around holding the device open. */
for (i = 0; i < HVMAXARCHITECTEDLPS; ++i)
veth_stop_connection(i);
HvLpEvent_unregisterHandler(HvLpEvent_Type_VirtualLan);
/* Hypervisor callbacks may have scheduled more work while we
- * were destroying connections. Now that we've disconnected from
+ * were stoping connections. Now that we've disconnected from
* the hypervisor make sure everything's finished. */
flush_scheduled_work();
+ vio_unregister_driver(&veth_driver);
+
for (i = 0; i < HVMAXARCHITECTEDLPS; ++i)
veth_destroy_connection(i);
|