net/dst: dst_dev_event() called after other notifiers
net/dst: dst_dev_event() called after other notifiers

Followup of commit ef885afbf8a37689 (net: use rcu_barrier() in
rollback_registered_many)

dst_dev_event() scans a garbage dst list that might be feeded by various
network notifiers at device dismantle time.

Its important to call dst_dev_event() after other notifiers, or we might
enter the infamous msleep(250) in netdev_wait_allrefs(), and wait one
second before calling again call_netdevice_notifiers(NETDEV_UNREGISTER,
dev) to properly remove last device references.

Use priority -10 to let dst_dev_notifier be called after other network
notifiers (they have the default 0 priority)

Reported-by: Ben Greear <a73a03e3b44aa05185cea6823d080c09a7808534@candelatech.com>
Reported-by: Nicolas Dichtel <7864bb1e0e12322ea18ea731d051b95b75140567@6wind.com>
Reported-by: Octavian Purdila <91308da0bf7e40e0a8ed5b7ced492510cbb48f46@ixiacom.com>
Reported-by: Benjamin LaHaise <b05c66fa21e46731bb89a779db663748f3df8f6a@kvack.org>
Tested-by: Ben Greear <a73a03e3b44aa05185cea6823d080c09a7808534@candelatech.com>
Signed-off-by: Eric Dumazet <a0baddf32b28d2f9429941ed4af2fe636e210591@gmail.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs