[TG3]: netif_carrier_off runs too early; could still be queued when init fails

Move the netif_carrier_off() call from tg3_init_one()->
tg3_init_link_config() to tg3_open() as is the convention for most other
network drivers.

I was getting a panic after a tg3 device failed to initialize due to DMA
failure.  The oops pointed to the link watch queue with spinlock debugging
enabled.  Without spinlock debugging, the Oops didn't occur.

I suspect that the link event was getting queued but not executed until
after the DMA test had failed and the device was freed.  The link event was
then operating on freed memory, which could contain anything.  With this
patch applied, the Oops no longer occurs.

[ Based upon feedback from Michael Chan, we move netif_carrier_off()
  to the end of tg3_init_one() instead of moving it to tg3_open() -DaveM ]

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index e0691cf16456..5104efe8ebfb 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -10926,7 +10926,6 @@ static void __devinit tg3_init_link_config(struct tg3 *tp)
 	tp->link_config.speed = SPEED_INVALID;
 	tp->link_config.duplex = DUPLEX_INVALID;
 	tp->link_config.autoneg = AUTONEG_ENABLE;
-	netif_carrier_off(tp->dev);
 	tp->link_config.active_speed = SPEED_INVALID;
 	tp->link_config.active_duplex = DUPLEX_INVALID;
 	tp->link_config.phy_is_low_power = 0;
@@ -11390,6 +11389,8 @@ static int __devinit tg3_init_one(struct pci_dev *pdev,
 	       (pdev->dma_mask == DMA_32BIT_MASK) ? 32 :
 	        (((u64) pdev->dma_mask == DMA_40BIT_MASK) ? 40 : 64));
 
+	netif_carrier_off(tp->dev);
+
 	return 0;
 
 err_out_iounmap: