addrconf_join_solict and addrconf_join_anycast may cause actions which
need rtnl locked, especially on first address creation.
A new DAD state is introduced which defers processing of the initial
DAD processing into a workqueue.
To get rtnl lock we need to push the code paths which depend on those
calls up to workqueues, specifically addrconf_verify and the DAD
processing.
(v2)
addrconf_dad_failure needs to be queued up to the workqueue, too. This
patch introduces a new DAD state and stop the DAD processing in the
workqueue (this is because of the possible ipv6_del_addr processing
which removes the solicited multicast address from the device).
addrconf_verify_lock is removed, too. After the transition it is not
needed any more.
As we are not processing in bottom half anymore we need to be a bit more
careful about disabling bottom half out when we lock spin_locks which are also
used in bh.
Relevant backtrace:
[ 541.030090] RTNL: assertion failed at net/core/dev.c (4496)
[ 541.031143] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.33-1-amd64-vyatta #1
[ 541.031145] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 541.031146] ffffffff8148a9f0 000000000000002f ffffffff813c98c1 ffff88007c4451f8
[ 541.031148] 0000000000000000 0000000000000000 ffffffff813d3540 ffff88007fc03d18
[ 541.031150] 0000880000000006 ffff88007c445000 ffffffffa0194160 0000000000000000
[ 541.031152] Call Trace:
[ 541.031153] <IRQ> [<ffffffff8148a9f0>] ? dump_stack+0xd/0x17
[ 541.031180] [<ffffffff813c98c1>] ? __dev_set_promiscuity+0x101/0x180
[ 541.031183] [<ffffffff813d3540>] ? __hw_addr_create_ex+0x60/0xc0
[ 541.031185] [<ffffffff813cfe1a>] ? __dev_set_rx_mode+0xaa/0xc0
[ 541.031189] [<ffffffff813d3a81>] ? __dev_mc_add+0x61/0x90
[ 541.031198] [<ffffffffa01dcf9c>] ? igmp6_group_added+0xfc/0x1a0 [ipv6]
[ 541.031208] [<ffffffff8111237b>] ? kmem_cache_alloc+0xcb/0xd0
[ 541.031212] [<ffffffffa01ddcd7>] ? ipv6_dev_mc_inc+0x267/0x300 [ipv6]
[ 541.031216] [<ffffffffa01c2fae>] ? addrconf_join_solict+0x2e/0x40 [ipv6]
[ 541.031219] [<ffffffffa01ba2e9>] ? ipv6_dev_ac_inc+0x159/0x1f0 [ipv6]
[ 541.031223] [<ffffffffa01c0772>] ? addrconf_join_anycast+0x92/0xa0 [ipv6]
[ 541.031226] [<ffffffffa01c311e>] ? __ipv6_ifa_notify+0x11e/0x1e0 [ipv6]
[ 541.031229] [<ffffffffa01c3213>] ? ipv6_ifa_notify+0x33/0x50 [ipv6]
[ 541.031233] [<ffffffffa01c36c8>] ? addrconf_dad_completed+0x28/0x100 [ipv6]
[ 541.031241] [<ffffffff81075c1d>] ? task_cputime+0x2d/0x50
[ 541.031244] [<ffffffffa01c38d6>] ? addrconf_dad_timer+0x136/0x150 [ipv6]
[ 541.031247] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
[ 541.031255] [<ffffffff8105313a>] ? call_timer_fn.isra.22+0x2a/0x90
[ 541.031258] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
Hunks and backtrace stolen from a patch by Stephen Hemminger.
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>