diff options
author | Dongdong Deng <dongdong.deng@windriver.com> | 2009-08-13 19:12:31 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2009-08-14 16:41:16 -0700 |
commit | 22580f894ac190c46beebb5c3172e450a2318f79 (patch) | |
tree | 01f88df9a5bc27170ef7ca944ba40af578476d72 /drivers/net/tulip/tulip_core.c | |
parent | 0527a1a8440a20b3d0fd1d0c9e75a6f38a9d5315 (diff) | |
download | linux-22580f894ac190c46beebb5c3172e450a2318f79.tar.bz2 |
drivers/net: fixed drivers that support netpoll use ndo_start_xmit()
The NETPOLL API requires that interrupts remain disabled in
netpoll_send_skb(). The use of spin_lock_irq() and spin_unlock_irq()
in the NETPOLL API callbacks causes the interrupts to get enabled and
can lead to kernel instability.
The solution is to use spin_lock_irqsave() and spin_unlock_restore()
to prevent the irqs from getting enabled while in netpoll_send_skb().
Call trace:
netpoll_send_skb()
{
-> local_irq_save(flags)
---> dev->ndo_start_xmit(skb, dev)
---> spin_lock_irq()
---> spin_unlock_irq() *******here would enable the interrupt.
...
-> local_irq_restore(flags)
}
Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/tulip/tulip_core.c')
-rw-r--r-- | drivers/net/tulip/tulip_core.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/tulip/tulip_core.c b/drivers/net/tulip/tulip_core.c index 99a63649f4fc..4cf9a6588751 100644 --- a/drivers/net/tulip/tulip_core.c +++ b/drivers/net/tulip/tulip_core.c @@ -652,8 +652,9 @@ tulip_start_xmit(struct sk_buff *skb, struct net_device *dev) int entry; u32 flag; dma_addr_t mapping; + unsigned long flags; - spin_lock_irq(&tp->lock); + spin_lock_irqsave(&tp->lock, flags); /* Calculate the next Tx descriptor entry. */ entry = tp->cur_tx % TX_RING_SIZE; @@ -688,7 +689,7 @@ tulip_start_xmit(struct sk_buff *skb, struct net_device *dev) /* Trigger an immediate transmit demand. */ iowrite32(0, tp->base_addr + CSR1); - spin_unlock_irq(&tp->lock); + spin_unlock_irqrestore(&tp->lock, flags); dev->trans_start = jiffies; |