ifb: fix rcu_sched self-detected stalls
authordingtianhong <dingtianhong@huawei.com>
Wed, 10 Jul 2013 04:04:02 +0000 (12:04 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 28 Jul 2013 23:29:58 +0000 (16:29 -0700)
commit6683151aeea6c7aade12dde7ec2008fc380f0728
treeb2a0af340bec8c897dcbfc45098f09eff26613a7
parentc51a7a308e2ff38ae5ad3005a7ce8c333779f8fd
ifb: fix rcu_sched self-detected stalls

[ Upstream commit 440d57bc5ff55ec1efb3efc9cbe9420b4bbdfefa ]

According to the commit 16b0dc29c1af9df341428f4c49ada4f626258082
(dummy: fix rcu_sched self-detected stalls)

Eric Dumazet fix the problem in dummy, but the ifb will occur the
same problem like the dummy modules.

Trying to "modprobe ifb numifbs=30000" triggers :

INFO: rcu_sched self-detected stall on CPU

After this splat, RTNL is locked and reboot is needed.

We must call cond_resched() to avoid this, even holding RTNL.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/net/ifb.c