The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and move the rtnl lock to protect the whole monitor function.
Signed-off-by: NDing Tianhong <dingtianhong@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit 278b2083
(bonding: initial RCU conversion) has convert the roundrobin,
active-backup, broadcast and xor xmit path to rcu protection,
the performance will be better for these mode, so this time,
convert xmit path for alb mode.
Signed-off-by: NDing Tianhong <dingtianhong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Cc: Nikolay Aleksandrov <nikolay@redhat.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, in TLB mode we change mac addresses only by memcpy-ing the to
net_device->dev_addr, without actually setting them via
dev_set_mac_address(). This permits us to receive all the traffic always on
one mac address.

However, in case the interface flips, some drivers might enforce the
mac filtering for its FW/HW based on current ->dev_addr, and thus we won't
be able to receive traffic on that interface, in case it will be selected
as active in TLB mode.

Fix it by setting the mac address forcefully on every new active slave that
we select in TLB mode.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Yuval Mintz <yuvalmin@broadcom.com>
Reported-by: NYuval Mintz <yuvalmin@broadcom.com>
Tested-by: NYuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently we verify if we have slaves by checking if bond->slave_list is
empty. Create a define bond_has_slaves() and use it, a bit more readable
and easier to change in the future.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, we're using bond_for_each_slave_from(), which is really hard to
implement under RCU and/or neighbour list.

Remove it and use bond_for_each_slave() instead, taking care of the last
used slave.

Also, rename next_rx_slave to rx_slave and store the current (last)
rx_slave.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It needs a list_head *iter, so add it wherever needed. Use both non-rcu and
rcu variants.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We only use it in rollback scenarios and can easily use the standart
bond_for_each_dev() instead.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, we distinguish neighbours (first-level linked devices) from
non-neighbours by the neighbour bool in the netdev_adjacent. This could be
quite time-consuming in case we would like to traverse *only* through
neighbours - cause we'd have to traverse through all devices and check for
this flag, and in a (quite common) scenario where we have lots of vlans on
top of bridge, which is on top of a bond - the bonding would have to go
through all those vlans to get its upper neighbour linked devices.

This situation is really unpleasant, cause there are already a lot of cases
when a device with slaves needs to go through them in hot path.

To fix this, introduce a new upper/lower device lists structure -
adj_list, which contains only the neighbours. It works always in
pair with the all_adj_list structure (renamed from upper/lower_dev_list),
i.e. both of them contain the same links, only that all_adj_list contains
also non-neighbour device links. It's really a small change visible,
currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't
change the main linked logic at all.

Also, add some comments a fix a name collision in
netdev_for_each_upper_dev_rcu() and rework the naming by the following
rules:

netdev_(all_)(upper|lower)_*

If "all_" is present, then we work with the whole list of upper/lower
devices, otherwise - only with direct neighbours. Uninline functions - to
get better stack traces.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

running bonding in ALB mode requires that learning packets be sent periodically,
so that the switch knows where to send responding traffic.  However, depending
on switch configuration, there may not be any need to send traffic at the
default rate of 3 packets per second, which represents little more than wasted
data.  Allow the ALB learning packet interval to be made configurable via sysfs
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NAcked-by: Veaceslav Falico <vfalico@redhat.com>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Store VID in ->vlan_id (if any), and remove the useless ->tag.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We're using it currently to verify if we have vlans before getting the tag
from the skb we're about to send. It's useless because the vlan_get_tag()
verifies if the skb has the tag (and returns an error if not), and we can
receive tagged skbs only if we *already* have vlans.

Plus, the current RCUed implementation is kind of useless anyway - the we
can remove the last vlan in the moment we return from the function.

So remove the only usage of it and the whole function.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently there are no real users of vlan_list/current_alb_vlan, only the
helpers which maintain them, so remove them.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, if there are vlans on top of bond, alb_send_learning_packets()
will never send LPs from the bond itself (i.e. untagged), which might leave
untagged clients unupdated.

Also, the 'circular vlan' logic (i.e. update only MAX_LP_BURST vlans at a
time, and save the last vlan for the next update) is really suboptimal - in
case of lots of vlans it will take a lot of time to update every vlan. It
is also never called in any hot path and sends only a few small packets -
thus the optimization by itself is useless.

So remove the whole current_alb_vlan/MAX_LP_BURST logic from
alb_send_learning_packets(). Instead, we'll first send a packet untagged
and then traverse the upper dev list, sending a tagged packet for each vlan
found. Also, remove the MAX_LP_BURST define - we already don't need it.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create alb_send_lp_vid(), which will handle the skb/lp creation, vlan
tagging and sending, and use it in alb_send_learning_packets().

This way all the logic remains in alb_send_learning_packets(), which
becomes a lot more cleaner and easier to understand.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch does the initial bonding conversion to RCU. After it the
following modes are protected by RCU alone: roundrobin, active-backup,
broadcast and xor. Modes ALB/TLB and 3ad still acquire bond->lock for
reading, and will be dealt with later. curr_active_slave needs to be
dereferenced via rcu in the converted modes because the only thing
protecting the slave after this patch is rcu_read_lock, so we need the
proper barrier for weakly ordered archs and to make sure we don't have
stale pointer. It's not tagged with __rcu yet because there's still work
to be done to remove the curr_slave_lock, so sparse will complain when
rcu_assign_pointer and rcu_dereference are used, but the alternative to use
rcu_dereference_protected would've created much bigger code churn which is
more difficult to test and review. That will be converted in time.

1. Active-backup mode
 1.1 Perf recording while doing iperf -P 4
  - old bonding: iperf spent 0.55% in bonding, system spent 0.29% CPU
                 in bonding
  - new bonding: iperf spent 0.29% in bonding, system spent 0.15% CPU
                 in bonding
 1.2. Bandwidth measurements
  - old bonding: 16.1 gbps consistently
  - new bonding: 17.5 gbps consistently

2. Round-robin mode
 2.1 Perf recording while doing iperf -P 4
  - old bonding: iperf spent 0.51% in bonding, system spent 0.24% CPU
                 in bonding
  - new bonding: iperf spent 0.16% in bonding, system spent 0.11% CPU
                 in bonding
 2.2 Bandwidth measurements
  - old bonding: 8 gbps (variable due to packet reorderings)
  - new bonding: 10 gbps (variable due to packet reorderings)

Of course the latency has improved in all converted modes, and moreover
while
doing enslave/release (since it doesn't affect tx anymore).

Also I've stress tested all modes doing enslave/release in a loop while
transmitting traffic.
Signed-off-by: NNikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch aims to remove struct bonding's first_slave and struct
slave's next and prev pointers, and replace them with the standard Linux
list API. The old macros are converted to list API as well and some new
primitives are available now. The checks if there're slaves that used
slave_cnt have been replaced by the list_empty macro.
Also a few small style fixes, changing longest -> shortest line in local
variable declarations, leaving an empty line before return and removing
unnecessary brackets.
This is the first step to gradual RCU conversion.
Signed-off-by: NNikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Also, cleanup bond_alb_handle_active_change() from 2 identical ifs.
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

alb_set_slave_mac_addr() sets the mac address in alb mode via
dev_set_mac_address(), which might sleep. It's called from
alb_handle_addr_collision_on_attach() in atomic context (under
read_lock(bond->lock)), thus triggering a bug.

Fix this by moving the lock inside alb_handle_addr_collision_on_attach().

v1->v2:
As Nikolay Aleksandrov noticed, we can drop the bond->lock completely.
Also, use bond_slave_has_mac(), when possible.
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NNikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After b924551b ("bonding: fix enslaving in alb mode when link down") we
don't need the bond parameter in alb_swap_mac_addr(), so remove it.
Signed-off-by: NVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a protocol argument to the VLAN packet tagging functions. In case of HW
tagging, we need that protocol available in the ndo_start_xmit functions,
so it is stored in a new field in the skb. The new field fits into a hole
(on 64 bit) and doesn't increase the sks's size.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Benefit from new upper dev list and free bonding from dev->master usage.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Bonding in balance-alb mode records information from ARP packets
passing through the bond in a hash table (rx_hashtbl).

At certain situations (e.g. link change of a slave),
rlb_update_rx_clients() will send out ARP packets to update ARP
caches of other hosts on the network to achieve RX load
balancing.

The problem is that once an IP address is recorded in the hash
table, it stays there indefinitely. If this IP address is
migrated to a different host in the network, bonding still sends
out ARP packets that poison other systems' ARP caches with
invalid information.

This patch solves this by looking at all incoming ARP packets,
and checking if the source IP address is one of the source
addresses stored in the rx_hashtbl. If it is, but the MAC
addresses differ, the corresponding hash table entries are
removed. Thus, when an IP address is migrated, the first ARP
broadcast by its new owner will purge the offending entries of
rx_hashtbl.

The hash table is hashed by ip_dst. To be able to do the above
check efficiently (not walking the whole hash table), we need a
reverse mapping (by ip_src).

I added three new members in struct rlb_client_info:
   rx_hashtbl[x].src_first will point to the start of a list of
      entries for which hash(ip_src) == x.
   The list is linked with src_next and src_prev.

When an incoming ARP packet arrives at rlb_arp_recv()
rlb_purge_src_ip() can quickly walk only the entries on the
corresponding lists, i.e. the entries that are likely to contain
the offending IP address.

To avoid confusion, I renamed these existing fields of struct
rlb_client_info:
	next -> used_next
	prev -> used_prev
	rx_hashtbl_head -> rx_hashtbl_used_head

(The current linked list is _not_ a list of hash table
entries with colliding ip_dst. It's a list of entries that are
being used; its purpose is to avoid walking the whole hash table
when looking for used entries.)
Signed-off-by: NJiri Bohac <jbohac@suse.cz>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do not modify or load balance ARP packets passing through balance-alb
mode (wherein the ARP did not originate locally, and arrived via a bridge).

Modifying pass-through ARP replies causes an incorrect MAC address
to be placed into the ARP packet, rendering peers unable to communicate
with the actual destination from which the ARP reply originated.

Load balancing pass-through ARP requests causes an entry to be
created for the peer in the rlb table, and bond_alb_monitor will
occasionally issue ARP updates to all peers in the table instrucing them
as to which MAC address they should communicate with; this occurs when
some event sets rx_ntt.  In the bridged case, however, the MAC address
used for the update would be the MAC of the slave, not the actual source
MAC of the originating destination.  This would render peers unable to
communicate with the destinations beyond the bridge.
Signed-off-by: NZheng Li <zheng.x.li@oracle.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When packets are dropped in TX path, its better to use kfree_skb()
instead of dev_kfree_skb() to give proper drop_monitor events.

Also move the kfree_skb() call after read_unlock() in bond_alb_xmit()
and bond_xmit_activebackup()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cloning all packets in input path have a significant cost.

Use skb_header_pointer()/skb_copy_bits() instead of pskb_may_pull() so
that recv_probe handlers (bond_3ad_lacpdu_recv / bond_arp_rcv /
rlb_arp_recv ) dont touch input skb.

bond_handle_frame() can avoid the skb_clone()/dev_kfree_skb()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Jiri Bohac <jbohac@suse.cz>
Cc: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Cc: Maciej Żenczykowski <maze@google.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I applied the wrong version of Jiri's bonding fix in commit
13a8e0c8 ("bonding: don't increase
rx_dropped after processing LACPDUs")

I applied v3, which introduces warnings I asked him to fix,
instead of v4 which properly takes care of those issues.

This inter-diffs such that the warnings are now gone.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the new bool function ether_addr_equal_64bits to add
some clarity and reduce the likelihood for misuse of
compare_ether_addr_64bits for sorting.

Done via cocci script:

$ cat compare_ether_addr_64bits.cocci
@@
expression a,b;
@@
-	!compare_ether_addr_64bits(a, b)
+	ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	compare_ether_addr_64bits(a, b)
+	!ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal_64bits(a, b) == 0
+	ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	!ether_addr_equal_64bits(a, b) != 0
+	!ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	ether_addr_equal_64bits(a, b) == 0
+	!ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	ether_addr_equal_64bits(a, b) != 0
+	ether_addr_equal_64bits(a, b)

@@
expression a,b;
@@
-	!!ether_addr_equal_64bits(a, b)
+	ether_addr_equal_64bits(a, b)
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

alloc failures use dump_stack so emitting an additional
out-of-memory message is an unnecessary duplication.

Remove the allocation failure messages.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

bond_alb_init_slave() is called from bond_enslave() and sets the slave's MAC
address. This is done differently for TLB and ALB modes.
bond->alb_info.rlb_enabled is used to discriminate between the two modes but
this flag may be uninitialized if the slave is being enslaved prior to calling
bond_open() -> bond_alb_initialize() on the master.

It turns out all the callers of alb_set_slave_mac_addr() pass
bond->alb_info.rlb_enabled as the hw parameter.

This patch cleans up the unnecessary parameter of alb_set_slave_mac_addr() and
makes the function decide based on the bonding mode instead, which fixes the
above problem.
Reported-by: NNarendra K <Narendra_K@Dell.com>
Signed-off-by: NJiri Bohac <jbohac@suse.cz>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No need to lock soft irqs under bond_alb_xmit()
which already has softirq disabled.

Changes:
1. add non-bh/bh version to tlb_clear_slave()

2. represent BH and non BH hash table locks
_lock_rx_hashtbl_bh/_unlock_rx_hashtbl_bh
_lock_rx_hashtbl/_unlock_rx_hashtbl
_lock_tx_hashtbl_bh/_unlock_tx_hashtbl_bh
_lock_tx_hashtbl/_unlock_tx_hashtbl
Signed-off-by: NMaxim Uvarov <maxim.uvarov@oracle.com>
Signed-off-by: NCong Wang <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch resolves two sets of race conditions.

	Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com> reported the
first, as follows:

The bond_close() calls cancel_delayed_work() to cancel delayed works.
It, however, cannot cancel works that were already queued in workqueue.
The bond_open() initializes work->data, and proccess_one_work() refers
get_work_cwq(work)->wq->flags. The get_work_cwq() returns NULL when
work->data has been initialized. Thus, a panic occurs.

	He included a patch that converted the cancel_delayed_work calls
in bond_close to flush_delayed_work_sync, which eliminated the above
problem.

	His patch is incorporated, at least in principle, into this
patch.  In this patch, we use cancel_delayed_work_sync in place of
flush_delayed_work_sync, and also convert bond_uninit in addition to
bond_close.

	This conversion to _sync, however, opens new races between
bond_close and three periodically executing workqueue functions:
bond_mii_monitor, bond_alb_monitor and bond_activebackup_arp_mon.

	The race occurs because bond_close and bond_uninit are always
called with RTNL held, and these workqueue functions may acquire RTNL to
perform failover-related activities.  If bond_close or bond_uninit is
waiting in cancel_delayed_work_sync, deadlock occurs.

	These deadlocks are resolved by having the workqueue functions
acquire RTNL conditionally.  If the rtnl_trylock() fails, the functions
reschedule and return immediately.  For the cases that are attempting to
perform link failover, a delay of 1 is used; for the other cases, the
normal interval is used (as those activities are not as time critical).

	Additionally, the bond_mii_monitor function now stores the delay
in a variable (mimicing the structure of activebackup_arp_mon).

	Lastly, all of the above renders the kill_timers sentinel moot,
and therefore it has been removed.
Tested-by: NMitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During a test where a pair of bonding interfaces using ARP monitoring
were both brought up and torn down (with an rmmod) repeatedly, a panic
in the timer code was noticed.  I tracked this down and determined that
any of the bonding functions that ran as workqueue handlers and requeued
more work might not properly exit when the module was removed.

There was a flag protected by the bond lock called kill_timers that is
set when the interface goes down or the module is removed, but many of
the functions that monitor link status now unlock the bond lock to take
rtnl first.  There is a chance that another CPU running the rmmod could
get the lock and set kill_timers after the first check has passed.

This patch does not allow any function to queue work that will make
itself run unless kill_timers is not set.  I also noticed while doing
this work that bond_resend_igmp_join_requests did not have a check for
kill_timers, so I added the needed call there as well.
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Reported-by: NLiang Zheng <lzheng@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now when all devices are cleaned up, bond can be cleaned up as well

- remove bond->vlgrp
- remove bond_vlan_rx_register
- substitute necessary occurences of vlan_group_get_device
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This soft lockup was recently reported:

[root@dell-per715-01 ~]# echo +bond5 > /sys/class/net/bonding_masters
[root@dell-per715-01 ~]# echo +eth1 > /sys/class/net/bond5/bonding/slaves
bonding: bond5: doing slave updates when interface is down.
bonding bond5: master_dev is not up in bond_enslave
[root@dell-per715-01 ~]# echo -eth1 > /sys/class/net/bond5/bonding/slaves
bonding: bond5: doing slave updates when interface is down.

BUG: soft lockup - CPU#12 stuck for 60s! [bash:6444]
CPU 12:
Modules linked in: bonding autofs4 hidp rfcomm l2cap bluetooth lockd sunrpc
be2d
Pid: 6444, comm: bash Not tainted 2.6.18-262.el5 #1
RIP: 0010:[<ffffffff80064bf0>]  [<ffffffff80064bf0>]
.text.lock.spinlock+0x26/00
RSP: 0018:ffff810113167da8  EFLAGS: 00000286
RAX: ffff810113167fd8 RBX: ffff810123a47800 RCX: 0000000000ff1025
RDX: 0000000000000000 RSI: ffff810123a47800 RDI: ffff81021b57f6f8
RBP: ffff81021b57f500 R08: 0000000000000000 R09: 000000000000000c
R10: 00000000ffffffff R11: ffff81011d41c000 R12: ffff81021b57f000
R13: 0000000000000000 R14: 0000000000000282 R15: 0000000000000282
FS:  00002b3b41ef3f50(0000) GS:ffff810123b27940(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00002b3b456dd000 CR3: 000000031fc60000 CR4: 00000000000006e0

Call Trace:
 [<ffffffff80064af9>] _spin_lock_bh+0x9/0x14
 [<ffffffff886937d7>] :bonding:tlb_clear_slave+0x22/0xa1
 [<ffffffff8869423c>] :bonding:bond_alb_deinit_slave+0xba/0xf0
 [<ffffffff8868dda6>] :bonding:bond_release+0x1b4/0x450
 [<ffffffff8006457b>] __down_write_nested+0x12/0x92
 [<ffffffff88696ae4>] :bonding:bonding_store_slaves+0x25c/0x2f7
 [<ffffffff801106f7>] sysfs_write_file+0xb9/0xe8
 [<ffffffff80016b87>] vfs_write+0xce/0x174
 [<ffffffff80017450>] sys_write+0x45/0x6e
 [<ffffffff8005d28d>] tracesys+0xd5/0xe0

It occurs because we are able to change the slave configuarion of a bond while
the bond interface is down.  The bonding driver initializes some data structures
only after its ndo_open routine is called.  Among them is the initalization of
the alb tx and rx hash locks.  So if we add or remove a slave without first
opening the bond master device, we run the risk of trying to lock/unlock a
spinlock that has garbage for data in it, which results in our above softlock.

Note that sometimes this works, because in many cases an unlocked spinlock has
the raw_lock parameter initialized to zero (meaning that the kzalloc of the
net_device private data is equivalent to calling spin_lock_init), but thats not
true in all cases, and we aren't guaranteed that condition, so we need to pass
the relevant spinlocks through the spin_lock_init function.

Fix it by moving the spin_lock_init calls for the tx and rx hashtable locks to
the ndo_init path, so they are ready for use by the bond_store_slaves path.

Change notes:
v2) Based on conversation with Jay and Nicolas it seems that the ability to
enslave devices while the bond master is down should be safe to do.  As such
this is an outlier bug, and so instead we'll just initalize the errant spinlocks
in the init path rather than the open path, solving the problem.  We'll also
remove the warnings about the bond being down during enslave operations, since
it should be safe

v3) Fix spelling error
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Reported-by: jtluka@redhat.com
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: nicolas.2p.debian@gmail.com
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull read_lock(&bond->lock) and BOND_IS_OK() to bond_start_xmit() from
mode-dependent xmit functions.

netif_running() is always true in hard_start_xmit.
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since now when bonding uses rx_handler, all traffic going into bond
device goes thru bond_handle_frame. So there's no need to go back into
bonding code later via ptype handlers. This patch converts
original ptype handlers into "bonding receive probes". These functions
are called from bond_handle_frame and they are registered per-mode.

Note that vlan packets are also handled because they are always untagged
thanks to vlan_untag()

Note that this also allows arpmon for eth-bond-bridge-vlan topology.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

replace relpy with reply.
replace premanent with permanent.
Signed-off-by: NWeiping Pan(潘卫平) <panweiping3@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is unnecessary to set save_load to 1 here,
as the tx_hashtbl is just kzalloced.
Signed-off-by: NWeiping Pan(潘卫平) <panweiping3@gmail.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Clearly it should be the size of ->ip_dst here.
Although this is harmless, but it still reads odd.
Signed-off-by: NWANG Cong <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Recently reported oops:

kernel BUG at net/core/skbuff.c:813!
invalid opcode: 0000 [#1] SMP
last sysfs file: /sys/devices/virtual/net/bond0/broadcast
CPU 8
Modules linked in: sit tunnel4 cpufreq_ondemand acpi_cpufreq freq_table bonding
ipv6 dm_mirror dm_region_hash dm_log cdc_ether usbnet mii serio_raw i2c_i801
i2c_core iTCO_wdt iTCO_vendor_support shpchp ioatdma i7core_edac edac_core bnx2
ixgbe dca mdio sg ext4 mbcache jbd2 sd_mod crc_t10dif mptsas mptscsih mptbase
scsi_transport_sas dm_mod [last unloaded: microcode]

Modules linked in: sit tunnel4 cpufreq_ondemand acpi_cpufreq freq_table bonding
ipv6 dm_mirror dm_region_hash dm_log cdc_ether usbnet mii serio_raw i2c_i801
i2c_core iTCO_wdt iTCO_vendor_support shpchp ioatdma i7core_edac edac_core bnx2
ixgbe dca mdio sg ext4 mbcache jbd2 sd_mod crc_t10dif mptsas mptscsih mptbase
scsi_transport_sas dm_mod [last unloaded: microcode]
Pid: 0, comm: swapper Not tainted 2.6.32-71.el6.x86_64 #1 BladeCenter HS22
-[7870AC1]-
RIP: 0010:[<ffffffff81405b16>]  [<ffffffff81405b16>]
pskb_expand_head+0x36/0x1e0
RSP: 0018:ffff880028303b70  EFLAGS: 00010202
RAX: 0000000000000002 RBX: ffff880c6458ec80 RCX: 0000000000000020
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880c6458ec80
RBP: ffff880028303bc0 R08: ffffffff818a6180 R09: ffff880c6458ed64
R10: ffff880c622b36c0 R11: 0000000000000400 R12: 0000000000000000
R13: 0000000000000180 R14: ffff880c622b3000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff880028300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 00000038653452a4 CR3: 0000000001001000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper (pid: 0, threadinfo ffff8806649c2000, task ffff880c64f16ab0)
Stack:
 ffff880028303bc0 ffffffff8104fff9 000000000000001c 0000000100000000
<0> ffff880000047d80 ffff880c6458ec80 000000000000001c ffff880c6223da00
<0> ffff880c622b3000 0000000000000000 ffff880028303c10 ffffffff81407f7a
Call Trace:
<IRQ>
 [<ffffffff8104fff9>] ? __wake_up_common+0x59/0x90
 [<ffffffff81407f7a>] __pskb_pull_tail+0x2aa/0x360
 [<ffffffffa0244530>] bond_arp_rcv+0x2c0/0x2e0 [bonding]
 [<ffffffff814a0857>] ? packet_rcv+0x377/0x440
 [<ffffffff8140f21b>] netif_receive_skb+0x2db/0x670
 [<ffffffff8140f788>] napi_skb_finish+0x58/0x70
 [<ffffffff8140fc89>] napi_gro_receive+0x39/0x50
 [<ffffffffa01286eb>] ixgbe_clean_rx_irq+0x35b/0x900 [ixgbe]
 [<ffffffffa01290f6>] ixgbe_clean_rxtx_many+0x136/0x240 [ixgbe]
 [<ffffffff8140fe53>] net_rx_action+0x103/0x210
 [<ffffffff81073bd7>] __do_softirq+0xb7/0x1e0
 [<ffffffff810d8740>] ? handle_IRQ_event+0x60/0x170
 [<ffffffff810142cc>] call_softirq+0x1c/0x30
 [<ffffffff81015f35>] do_softirq+0x65/0xa0
 [<ffffffff810739d5>] irq_exit+0x85/0x90
 [<ffffffff814cf915>] do_IRQ+0x75/0xf0
 [<ffffffff81013ad3>] ret_from_intr+0x0/0x11
 <EOI>
 [<ffffffff8101bc01>] ? mwait_idle+0x71/0xd0
 [<ffffffff814cd80a>] ? atomic_notifier_call_chain+0x1a/0x20
 [<ffffffff81011e96>] cpu_idle+0xb6/0x110
 [<ffffffff814c17c8>] start_secondary+0x1fc/0x23f

Resulted from bonding driver registering packet handlers via dev_add_pack and
then trying to call pskb_may_pull. If another packet handler (like for AF_PACKET
sockets) gets called first, the delivered skb will have a user count > 1, which
causes pskb_may_pull to BUG halt when it does its skb_shared check.  Fix this by
calling skb_share_check prior to the may_pull call sites in the bonding driver
to clone the skb when needed.  Tested by myself and the reported successfully.

Signed-off-by: Neil Horman
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>