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| author | Cong Wang <xiyou.wangcong@gmail.com> | 2020-06-08 23:53:01 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-06-09 21:59:45 +0200 |
| commit | 845e0ebb4408d4473cf60d21224a897037e9a77a (patch) | |
| tree | 053282d21248269b50668f920d39ba07b7a0277d /include | |
| parent | selftests/net: in timestamping, strncpy needs to preserve null byte (diff) | |
| download | linux-845e0ebb4408d4473cf60d21224a897037e9a77a.tar.xz linux-845e0ebb4408d4473cf60d21224a897037e9a77a.zip | |
net: change addr_list_lock back to static key
The dynamic key update for addr_list_lock still causes troubles,
for example the following race condition still exists:
CPU 0: CPU 1:
(RCU read lock) (RTNL lock)
dev_mc_seq_show() netdev_update_lockdep_key()
-> lockdep_unregister_key()
-> netif_addr_lock_bh()
because lockdep doesn't provide an API to update it atomically.
Therefore, we have to move it back to static keys and use subclass
for nest locking like before.
In commit 1a33e10e4a95 ("net: partially revert dynamic lockdep key
changes"), I already reverted most parts of commit ab92d68fc22f
("net: core: add generic lockdep keys").
This patch reverts the rest and also part of commit f3b0a18bb6cb
("net: remove unnecessary variables and callback"). After this
patch, addr_list_lock changes back to using static keys and
subclasses to satisfy lockdep. Thanks to dev->lower_level, we do
not have to change back to ->ndo_get_lock_subclass().
And hopefully this reduces some syzbot lockdep noises too.
Reported-by: syzbot+f3a0e80c34b3fc28ac5e@syzkaller.appspotmail.com
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/netdevice.h | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1a96e9c4ec36..e2825e27ef89 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1821,8 +1821,6 @@ enum netdev_priv_flags { * for hardware timestamping * @sfp_bus: attached &struct sfp_bus structure. * - * @addr_list_lock_key: lockdep class annotating - * net_device->addr_list_lock spinlock * @qdisc_tx_busylock: lockdep class annotating Qdisc->busylock spinlock * @qdisc_running_key: lockdep class annotating Qdisc->running seqcount * @@ -2125,7 +2123,6 @@ struct net_device { #endif struct phy_device *phydev; struct sfp_bus *sfp_bus; - struct lock_class_key addr_list_lock_key; struct lock_class_key *qdisc_tx_busylock; struct lock_class_key *qdisc_running_key; bool proto_down; @@ -2217,10 +2214,13 @@ static inline void netdev_for_each_tx_queue(struct net_device *dev, static struct lock_class_key qdisc_tx_busylock_key; \ static struct lock_class_key qdisc_running_key; \ static struct lock_class_key qdisc_xmit_lock_key; \ + static struct lock_class_key dev_addr_list_lock_key; \ unsigned int i; \ \ (dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key; \ (dev)->qdisc_running_key = &qdisc_running_key; \ + lockdep_set_class(&(dev)->addr_list_lock, \ + &dev_addr_list_lock_key); \ for (i = 0; i < (dev)->num_tx_queues; i++) \ lockdep_set_class(&(dev)->_tx[i]._xmit_lock, \ &qdisc_xmit_lock_key); \ @@ -3253,7 +3253,6 @@ static inline void netif_stop_queue(struct net_device *dev) } void netif_tx_stop_all_queues(struct net_device *dev); -void netdev_update_lockdep_key(struct net_device *dev); static inline bool netif_tx_queue_stopped(const struct netdev_queue *dev_queue) { @@ -4239,6 +4238,11 @@ static inline void netif_addr_lock(struct net_device *dev) spin_lock(&dev->addr_list_lock); } +static inline void netif_addr_lock_nested(struct net_device *dev) +{ + spin_lock_nested(&dev->addr_list_lock, dev->lower_level); +} + static inline void netif_addr_lock_bh(struct net_device *dev) { spin_lock_bh(&dev->addr_list_lock); |