| Date | Tue, 26 Mar 2013 13:22:20 -0400 | From | Steven Rostedt <> | Subject | [PATCH 81/86] ppp: set qdisc_tx_busylock to avoid LOCKDEP splat |
| |
3.6.11.1 stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@google.com>
[ Upstream commit 0b652fb68c02c1acd0307d3acac4ae7123536031 ]
If a qdisc is installed on a ppp device, its possible to get a lockdep splat under stress, because nested dev_queue_xmit() can lock busylock a second time (on a different device, so its a false positive)
Avoid this problem using a distinct lock_class_key for ppp devices.
Reported-by: Yanko Kaneti <yaneti@declera.com> Tested-by: Yanko Kaneti <yaneti@declera.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- drivers/net/ppp/ppp_generic.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 5c05572..2603b99 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -1021,7 +1021,15 @@ ppp_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) return err; } +static struct lock_class_key ppp_tx_busylock; +static int ppp_dev_init(struct net_device *dev) +{ + dev->qdisc_tx_busylock = &ppp_tx_busylock; + return 0; +} + static const struct net_device_ops ppp_netdev_ops = { + .ndo_init = ppp_dev_init, .ndo_start_xmit = ppp_start_xmit, .ndo_do_ioctl = ppp_net_ioctl, }; -- 1.7.10.4
|