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/b44.c | |
parent | 0527a1a8440a20b3d0fd1d0c9e75a6f38a9d5315 (diff) | |
download | kernel_samsung_smdk4412-22580f894ac190c46beebb5c3172e450a2318f79.zip kernel_samsung_smdk4412-22580f894ac190c46beebb5c3172e450a2318f79.tar.gz kernel_samsung_smdk4412-22580f894ac190c46beebb5c3172e450a2318f79.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/b44.c')
-rw-r--r-- | drivers/net/b44.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/b44.c b/drivers/net/b44.c index 36d4d37..bafca67 100644 --- a/drivers/net/b44.c +++ b/drivers/net/b44.c @@ -952,9 +952,10 @@ static int b44_start_xmit(struct sk_buff *skb, struct net_device *dev) int rc = NETDEV_TX_OK; dma_addr_t mapping; u32 len, entry, ctrl; + unsigned long flags; len = skb->len; - spin_lock_irq(&bp->lock); + spin_lock_irqsave(&bp->lock, flags); /* This is a hard error, log it. */ if (unlikely(TX_BUFFS_AVAIL(bp) < 1)) { @@ -1027,7 +1028,7 @@ static int b44_start_xmit(struct sk_buff *skb, struct net_device *dev) dev->trans_start = jiffies; out_unlock: - spin_unlock_irq(&bp->lock); + spin_unlock_irqrestore(&bp->lock, flags); return rc; |