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>

For backward compatibility, we should retain the module parameters and
sysfs attributes to control the number of peer notifications
(gratuitous ARPs and unsolicited NAs) sent after bonding failover.
Also, it is possible for failover to take place even though the new
active slave does not have link up, and in that case the peer
notification should be deferred until it does.

Change ipv4 and ipv6 so they do not automatically send peer
notifications on bonding failover.

Change the bonding driver to send separate NETDEV_NOTIFY_PEERS
notifications when the link is up, as many times as requested.  Since
it does not directly control which protocols send notifications, make
num_grat_arp and num_unsol_na aliases for a single parameter.  Bump
the bonding version number and update its documentation.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Acked-by: NBrian Haley <brian.haley@hp.com>
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>

It is undesirable for the bonding driver to be poking into higher
level protocols, and notifiers provide a way to avoid that.  This does
mean removing the ability to configure reptitition of gratuitous ARPs
and unsolicited NAs.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since bond-related code was moved from net/core/dev.c into bonding,
IFF_SLAVE_INACTIVE is no longer needed. Replace is with flag "inactive"
stored in slave structure
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Reviewed-by: NNicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

transfers slave->state into slave->backup (that it's going to transfer
into bitfield. Introduce wrapper inlines to do the work with it.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Reviewed-by: NNicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now when bond-related code is moved from net/core/dev.c into bonding
code, multiple priv_flags are not needed anymore. So let them rot.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Reviewed-by: NNicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the bonding module is loaded, it creates bond0 by default.
Then, when attempting to create bond0, the following messages
are printed to syslog:

    kernel: bonding: bond0 is being created...
    kernel: bonding: Bond creation failed.

Which seems to indicate a problem, when in reality there is no
problem.  Since the actual error code is passed down from bond_create,
make use of it to print a bit less ominous message:

    kernel: bonding: bond0 is being created...
    kernel: bond0 already exists.
Signed-off-by: NPhil Oester <kernel@linuxace.com>
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

count is incorrectly returned even in case of fail. Return ret instead.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The monitoring paths in the bonding driver take write locks that are shared by
the tx path.  If netconsole is in use, these paths can call printk which puts us
in the netpoll tx path, which, if netconsole is attached to the bonding driver,
result in deadlock (the xmit_lock guards are useless in netpoll_send_skb, as the
monitor paths in the bonding driver don't claim the xmit_lock, nor should they).
The solution is to use a per cpu flag internal to the driver to indicate when a
cpu is holding the lock in a path that might recusrse into the tx path for the
driver via netconsole.  By checking this flag on transmit, we can defer the
sending of the netconsole frames until a later time using the retransmit feature
of netpoll_send_skb that is triggered on the return code NETDEV_TX_BUSY.  I've
tested this and am able to transmit via netconsole while causing failover
conditions on the bond slave links.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow sysadmins to configure the number of multicast
membership report sent on a link failure event.
Signed-off-by: NFlavio Leitner <fleitner@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using module options arp monitoring and balance-alb/balance-tlb
are mutually exclusive options.  Anytime balance-alb/balance-tlb are
enabled mii monitoring is forced to 100ms if not set.  When configuring
via sysfs no checking is currently done.

Handling these cases with sysfs has to be done a bit differently because
we do not have all configuration information available at once.  This
patch will not allow a mode change to balance-alb/balance-tlb if
arp_interval is already non-zero.  It will also not allow the user to
set a non-zero arp_interval value if the mode is already set to
balance-alb/balance-tlb.  They are still mutually exclusive on a
first-come, first serve basis.

Tested with initscripts on Fedora and manual setting via sysfs.
Signed-off-by: NAndy Gospodarek <gospo@redhat.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The test for buffer overflow ensures we have room for 6 more bytes.
sprintf, called with %s:%d, slave->dev->name, slave->queue_id may yield
far more than 6 bytes.

The correct test is res > (PAGE_SIZE - IFNAMSIZ - 6) .
Signed-off-by: NNicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

v2: changed bonding module version, modified to apply on top of changes
from previous patch in series, and updated documentation to elaborate on
multiqueue awareness that now exists in bonding driver.

This patch give the user the ability to control the output slave for
round-robin and active-backup bonding.  Similar functionality was
discussed in the past, but Jay Vosburgh indicated he would rather see a
feature like this added to existing modes rather than creating a
completely new mode.  Jay's thoughts as well as Neil's input surrounding
some of the issues with the first implementation pushed us toward a
design that relied on the queue_mapping rather than skb marks.
Round-robin and active-backup modes were chosen as the first users of
this slave selection as they seemed like the most logical choices when
considering a multi-switch environment.

Round-robin mode works without any modification, but active-backup does
require inclusion of the first patch in this series and setting
the 'all_slaves_active' flag.  This will allow reception of unicast traffic on
any of the backup interfaces.

This was tested with IPv4-based filters as well as VLAN-based filters
with good results.

More information as well as a configuration example is available in the
patch to Documentation/networking/bonding.txt.
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

v2: changed parameter name from 'keep_all' to 'all_slaves_active' and
skipped setting slaves to inactive rather than creating a new flag at
Jay's suggestion.

In an effort to suppress duplicate frames on certain bonding modes
(specifically the modes that do not require additional configuration on
the switch or switches connected to the host), code was added in the
generic receive patch in 2.6.16.  The current behavior works quite well
for most users, but there are some times it would be nice to restore old
functionality and allow all frames to make their way up the stack.

This patch adds support for a new module option and sysfs file called
'all_slaves_active' that will restore pre-2.6.16 functionality if the
user desires.  The default value is '0' and retains existing behavior,
but the user can set it to '1' and allow all frames up if desired.
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the code that copies slave's mac address in case that's the first slave into
bond_enslave. Ifenslave app does this also but that's not a problem. This is
something that should be done in bond_enslave, and it shound not matter from
where is it called.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes bonding_store_slaves function nicer and easier to understand.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

(it's actually the same as v1)

Remove checks that duplicates similar checks in bond_enslave.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

V1->V2: corrected res/ret use

For some reason, MTU handling (storing, and restoring) is taking  place in
bond_sysfs. The correct place for this code is in bond_enslave, bond_release.
So move it there.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Passing the attribute to the low level IO functions allows all kinds
of cleanups, by sharing low level IO code without requiring
an own function for every piece of data.

Also drivers can extend the attributes with own data fields
and use that in the low level function.

This makes the class attributes the same as sysdev_class attributes
and plain attributes.

This will allow further cleanups in drivers.

Full tree sweep converting all users.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
Remove DRV_NAME from pr_<level>s
Consolidate long format strings
Remove some extra tab indents
Remove some unnecessary ()s from pr_<level>s arguments
Align pr_<level> arguments
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch delegates the work of creating the sysfs groups
to the netdev layer and ultimately to the device layer.  This
closes races between uevents.
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>

In some cases there is not desirable to switch back to primary interface when
it's link recovers and rather stay with currently active one. We need to avoid
packetloss as much as we can in some cases. This is solved by introducing
primary_reselect option. Note that enslaved primary slave is set as current
active no matter what.

Patch modified by Jay Vosburgh as follows: fixed bug in action
after change of option setting via sysfs, revised the documentation
update, and bumped the bonding version number.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Primary module parameter passed to bonding is pernament. That means if you
release the primary slave and enslave it again, it becomes the primary slave
again. But if you set primary slave via sysfs, the primary slave is only set
once and it's not remembered in bond->params structure. Therefore the setting is
lost after releasing the primary slave. This simple one-liner fixes this.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I did not introduce new lines over 80 chars. I even eliminated some of
them.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove bogus non-portable possibly unaligned way of testing
for zero addres..
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The bonding device acts unlike all other Linux network device functions
in that it ignores case of device names. The developer must have come
from windows!

Cleanup the management of names and use standard routines where possible.
Flag places where bonding device still doesn't work right with network
namespaces.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The "expected_refcount" stuff in bonding sysfs module is a mistake.
Sysfs does proper refcounting, and it is okay to remove a bond device
that has some user process holding the file open.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Resolve some of the complaints from checkpatch, and remove "magic emacs format"
comments, and useless MODULE_SUPPORTED_DEVICE(). But should not
change actual code.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is not safe to use a network device destructor that is a function in
the module, since it can be called after module is unloaded if sysfs
handle is open.

When eventually using netlink, the device cleanup code needs to be done
via uninit function.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The whole read/write semaphore locking can be removed. It doesn't add any
protection that isn't already done by using the RTNL mutex properly.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

bond_create() is always called with same parameters so move the argument
down.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some users still load bond module multiple times to create bonding
devices.  This accidentally was broken by a later patch about
the time sysfs was fixed.  According to Jay, it was broken
by:
   commit b8a9787e
   Author: Jay Vosburgh <fubar@us.ibm.com>
   Date:   Fri Jun 13 18:12:04 2008 -0700

     bonding: Allow setting max_bonds to zero

Note: sysfs and procfs still produce WARN() messages when this is done
so the sysfs method is the recommended API.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sysfs files for a network device can not unconditionally take the
rtnl_lock as the bonding sysfs files do.  If someone accesses those
sysfs files while the network device is being unregistered with the
rtnl_lock held we will deadlock.

So use trylock and restart_syscall to avoid this problem.
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix a zero address hole bug in the bonding arp_ip_target list
that was causing the bond to ignore ARP replies (bugz 13006).
Instead of just setting the array entry to zero, we now
copy any additional entries down one slot, putting the
zero entry at the end.  With this change we can now have
all the loops that walk the array stop when they hit a zero
since there will be no addresses after it.

Changes are based in part on code fragment provided in kernel:
bugzilla 13006:

	http://bugzilla.kernel.org/show_bug.cgi?id=13006

by Steve Howard <steve@astutenetworks.com>
Signed-off-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix this sparse warnings:

  drivers/net/bonding/bond_main.c:104:20: warning: symbol 'bonding_defaults' was not declared. Should it be static?
  drivers/net/bonding/bond_main.c:204:22: warning: symbol 'ad_select_tbl' was not declared. Should it be static?
  drivers/net/bonding/bond_sysfs.c:60:21: warning: symbol 'bonding_rwsem' was not declared. Should it be static?
Signed-off-by: NHannes Eder <hannes@hanneseder.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove some declarations from bonding.c as they are declared in bonding.h
already.
Signed-off-by: NHolger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>