sky2: Avoid transmits during sky2_down()

This patch supersedes my previous patch "sky2: Avoid transmitting
during sky2_restart".

I have reworked the patch to avoid crashes during both sky2_restart()
and sky2_set_ringparam().

Without this patch, the sky2 driver can be crashed by doing:

# pktgen eth1 &    (transmit many packets on eth1)
# ethtool -G eth1 tx 510

I am aware you object to storing extra state, but I can't see a way
around this. Without remembering that we're restarting,
netif_wake_queue() is called in the ISR from sky2_tx_complete(), and
netif_tx_lock() is used in sky2_tx_done().  If anybody can see a way
around this, please let me know.

Signed-off-by: Mike McCormack <mikem@ring3k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index b5549c9e5107..4486b066b43f 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -2051,6 +2051,7 @@ struct sky2_port {
         u8                   duplex;    /* DUPLEX_HALF, DUPLEX_FULL */
         u8                   rx_csum;
         u8                   wol;
+        u8                   restarting;
         enum flow_control    flow_mode;
         enum flow_control    flow_status;