Improve code readablity by adding inline functions
to read specific BTH/IB fields without knowledge of
byte offsets.
Reviewed-by: NBrian Welty <brian.welty@intel.com>
Reviewed-by: NDasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDon Hiatt <don.hiatt@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Allow requesting of zero UDP checksum for encapsulated packets. The name and
meaning of the attribute is "NO_CSUM" in order to have the same meaning of
the attribute missing and being 0.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's nicer to return void, since then there's no need to
cast to any structures. Currently none of the users have
a cast, but a number of future conversions do.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Software implementation of transport layer security, implemented using ULP
infrastructure.  tcp proto_ops are replaced with tls equivalents of sendmsg and
sendpage.

Only symmetric crypto is done in the kernel, keys are passed by setsockopt
after the handshake is complete.  All control messages are supported via CMSG
data - the actual symmetric encryption is the same, just the message type needs
to be passed separately.

For user API, please see Documentation patch.

Pieces that can be shared between hw and sw implementation
are in tls_main.c
Signed-off-by: NBoris Pismenny <borisp@mellanox.com>
Signed-off-by: NIlya Lesokhin <ilyal@mellanox.com>
Signed-off-by: NAviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: NDave Watson <davejwatson@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Export do_tcp_sendpages and tcp_rate_check_app_limited, since tls will need to
sendpages while the socket is already locked.

tcp_sendpage is exported, but requires the socket lock to not be held already.
Signed-off-by: NAviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: NIlya Lesokhin <ilyal@mellanox.com>
Signed-off-by: NBoris Pismenny <borisp@mellanox.com>
Signed-off-by: NDave Watson <davejwatson@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the infrustructure for attaching Upper Layer Protocols (ULPs) over TCP
sockets. Based on a similar infrastructure in tcp_cong.  The idea is that any
ULP can add its own logic by changing the TCP proto_ops structure to its own
methods.

Example usage:

setsockopt(sock, SOL_TCP, TCP_ULP, "tls", sizeof("tls"));

modules will call:
tcp_register_ulp(&tcp_tls_ulp_ops);

to register/unregister their ulp, with an init function and name.

A list of registered ulps will be returned by tcp_get_available_ulp, which is
hooked up to /proc.  Example:

$ cat /proc/sys/net/ipv4/tcp_available_ulp
tls

There is currently no functionality to remove or chain ULPs, but
it should be possible to add these in the future if needed.
Signed-off-by: NBoris Pismenny <borisp@mellanox.com>
Signed-off-by: NDave Watson <davejwatson@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Update ->ndo_change_mtu() callback comment to remove text
about returning error in case of undefined callback. This
change makes the comment match the existing code behavior.
Signed-off-by: NMagnus Damm <damm+renesas@opensource.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, verifier will reject a program if it contains an
narrower load from the bpf context structure. For example,
        __u8 h = __sk_buff->hash, or
        __u16 p = __sk_buff->protocol
        __u32 sample_period = bpf_perf_event_data->sample_period
which are narrower loads of 4-byte or 8-byte field.

This patch solves the issue by:
  . Introduce a new parameter ctx_field_size to carry the
    field size of narrower load from prog type
    specific *__is_valid_access validator back to verifier.
  . The non-zero ctx_field_size for a memory access indicates
    (1). underlying prog type specific convert_ctx_accesses
         supporting non-whole-field access
    (2). the current insn is a narrower or whole field access.
  . In verifier, for such loads where load memory size is
    less than ctx_field_size, verifier transforms it
    to a full field load followed by proper masking.
  . Currently, __sk_buff and bpf_perf_event_data->sample_period
    are supporting narrowing loads.
  . Narrower stores are still not allowed as typical ctx stores
    are just normal stores.

Because of this change, some tests in verifier will fail and
these tests are removed. As a bonus, rename some out of bound
__sk_buff->cb access to proper field name and remove two
redundant "skb cb oob" tests.
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for supporting multiple CPU ports with DSA, have the
dsa_port structure know which CPU it is associated with. This will be
important in order to make sure the correct CPU is used for transmission
of the frames. If not for functional reasons, for performance (e.g: load
balancing) and forwarding decisions.
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Relocate master_ethtool_ops and master_orig_ethtool_ops into struct
dsa_port in order to be both consistent, and make things self contained
within the dsa_port structure.

This is a preliminary change to supporting multiple CPU port interfaces.
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for supporting multiple CPU ports, remove
dst->master_netdev and ds->master_netdev and replace them with only one
instance of the common object we have for a port: struct
dsa_port::netdev. ds->master_netdev is currently write only and would be
helpful in the case where we have two switches, both with CPU ports, and
also connected within each other, which the multi-CPU port patch series
would address.

While at it, introduce a helper function used in net/dsa/slave.c to
immediately get a reference on the master network device called
dsa_master_netdev().
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The of_mdio_parse_addr() helper function is useful to other code, but
the module dependency chain causes issues.  To work around this, we can
move of_mdio_parse_addr() to be an inline function in the header file.
This gets rid of the dependencies and still allows for the reuse of
code.
Reported-by: NLiviu Dudau <liviu@dudau.co.uk>
Signed-off-by: NJon Mason <jon.mason@broadcom.com>
Fixes: 342fa196 ("mdio: mux: make child bus walking more permissive and errors more verbose")
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make return value void since function never return meaningfull value
Signed-off-by: NYuval Shaia <yuval.shaia@oracle.com>
Acked-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 4c5e7a2c ("dt-bindings: mdio: Clarify binding document")
declared that a MDIO reset GPIO property should have only a single GPIO
reference/specifier, however the supporting code was left intact, still
burdening the kernel with now apparently useless loops -- get rid of them.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The description of NL80211_CMD_ROAM indicated possibility for a
request to roam issued by user-space. However, it also states that
as not being implemented right now. This has been so since commit
b23aa676 ("cfg80211: connect/disconnect API") added in 2009.
So it seems safe to assume it will not be added any time soon and
thus remove it.
Signed-off-by: NArend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Drivers that initiate roaming while being connected to a network that
uses 802.1X authentication need to inform user space if 802.1X
authentication is further required after roaming.
For example, when using the Fast transition protocol, roaming within
the mobility domain does not require new 802.1X authentication, but
roaming to another mobility domain does.
In addition, some drivers may not support 802.1X authentication
(so it has to be done in user space), while other drivers do.

Add a flag to the roaming notification to indicate if user space is
required to do 802.1X authentication after the roaming or not.
This flag will only be used for networks that use 802.1X
authentication. For networks that do not use 802.1X authentication it
is assumed that no further action is required from user space after
the roaming notification.
Signed-off-by: NAvraham Stern <avraham.stern@intel.com>
Signed-off-by: NLuca Coelho <luciano.coelho@intel.com>
[arend.vanspriel@broadcom.com reuse NL80211_ATTR_PORT_AUTHORIZED]
Signed-off-by: NArend van Spriel <arend.vanspriel@broadcom.com>
[rebase to apply w/o the flag in CONNECT]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Add API for setting the PMK to the driver. For FT support, allow
setting also the PMK-R0 Name.

This can be used by drivers that support 4-Way handshake offload
while IEEE802.1X authentication is managed by upper layers.
Signed-off-by: NAvraham Stern <avraham.stern@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
[arend.vanspriel@broadcom.com: add WANT_1X_4WAY_HS attribute]
Signed-off-by: NArend van Spriel <arend.vanspriel@broadcom.com>
[reword NL80211_EXT_FEATURE_4WAY_HANDSHAKE_STA_1X docs a bit to
say that the device may require it]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Let drivers advertise support for station-mode 4-way handshake
offloading with a new NL80211_EXT_FEATURE_4WAY_HANDSHAKE_STA_PSK flag.

Extend use of NL80211_ATTR_PMK attribute indicating it might be passed
as part of NL80211_CMD_CONNECT command, and contain the PSK (which is
the PMK, hence the name.)

The driver/device is assumed to handle the 4-way handshake by
itself in this case (including key derivations, etc.), instead
of relying on the supplicant.

This patch is somewhat based on this one (by Vladimir Kondratiev):
https://patchwork.kernel.org/patch/1309561/.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NEliad Peller <eliadx.peller@intel.com>
Signed-off-by: NLuca Coelho <luciano.coelho@intel.com>
[arend.vanspriel@broadcom.com rebase dealing with existing ATTR_PMK]
Signed-off-by: NArend van Spriel <arend.vanspriel@broadcom.com>
[reword NL80211_EXT_FEATURE_4WAY_HANDSHAKE_STA_PSK docs to indicate
that this offload might be required]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since UDP no more uses sk->destructor, we can clear completely
the skb head state before enqueuing. Amend and use
skb_release_head_state() for that.

All head states share a single cacheline, which is not
normally used/accesses on dequeue. We can avoid entirely accessing
such cacheline implementing and using in the UDP code a specialized
skb free helper which ignores the skb head state.

This saves a cacheline miss at skb deallocation time.

v1 -> v2:
  replaced secpath_reset() with skb_release_head_state()
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The same code is replicated in 3 different places; move it to a
common helper.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Considering this case:

 1. A program opens a sysfs table file 65535 times, it can increase
    validation_count and first increment cause the table to be mapped:

     validation_count = 65535

 2. AML execution causes "Load" to be executed on the same
    table, this time it cannot increase validation_count, so
    validation_count remains:

      validation_count = 65535

 3. The program closes sysfs table file 65535 times, it can decrease
    validation_count and the last decrement cause the table to be
    unmapped:

     validation_count = 0

 4. AML code still accessing the loaded table, kernel crash can be
    observed.

To prevent that from happening, add a validation_count threashold.
When it is reached, the validation_count can no longer be
incremented/decremented to invalidate the table descriptor (means
preventing table unmappings)

Note that code added in acpi_tb_put_table() is actually a no-op but
changes the warning message into a "warn once" one. Lv Zheng.
Signed-off-by: NLv Zheng <lv.zheng@intel.com>
[ rjw: Changelog, comments ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit abb2ea7d ("compiler, clang: suppress warning for unused
static inline functions") just caused more warnings due to re-defining
the 'inline' macro.

So undef it before re-defining it, and also add the 'notrace' attribute
like the gcc version that this is overriding does.

Maybe this makes clang happier.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow for tc BPF programs to set a skb->hash, apart from clearing
and triggering a recalc that we have right now. It allows for BPF
to implement a custom hashing routine for skb_get_hash().
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

LL2 today is interrupt driven - when tx/rx completion arrives [or any
other indication], qed needs to operate on the connection and pass
the information to the protocol-driver [or internal qed consumer].
Since we have several flavors of ll2 employeed by the driver,
each handler needs to do an if-else to determine the right functionality
to use based on the connection type.

In order to make things more scalable [given that we're going to add
additional types of ll2 flavors] move the infrastrucutre into using
a callback-based approach - the callbacks would be provided as part
of the connection's initialization parameters.
Signed-off-by: NMichal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: NYuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A LL2 connection [qed_ll2_info] has a sub-structure of type qed_ll2_conn
that contain various inputs for ll2 acquisition, but the connection also
utilizes a couple of other inputs.

Restructure the input structure to include all the inputs and refactor
the code necessary to populate those.
Signed-off-by: NYuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This introduces qed_ll2_comp_rx_data as a public struct
and moves handling of Rx packets in LL2 into using it.
Signed-off-by: NYuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

First step in revising the LL2 interface, this declares
qed_ll2_tx_pkt_info as part of the ll2 interface, and uses it for
transmission instead of receiving lots of parameters.
Signed-off-by: NYuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ipvlan code already knows how to detect when a duplicate address is
about to be assigned to an ipvlan device.  However, that failure is not
propogated outward and leads to a silent failure.

Introduce a validation step at ip address creation time and allow device
drivers to register to validate the incoming ip addresses.  The ipvlan
code is the first consumer.  If it detects an address in use, we can
return an error to the user before beginning to commit the new ifa in
the networking code.

This can be especially useful if it is necessary to provision many
ipvlans in containers.  The provisioning software (or operator) can use
this to detect situations where an ip address is unexpectedly in use.
Signed-off-by: NKrister Johansen <kjlx@templeofstupid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NStephan Mueller <smueller@chronox.de>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

While a 'struct key' itself normally does not contain sensitive
information, Documentation/security/keys.txt actually encourages this:

     "Having a payload is not required; and the payload can, in fact,
     just be a value stored in the struct key itself."

In case someone has taken this advice, or will take this advice in the
future, zero the key structure before freeing it.  We might as well, and
as a bonus this could make it a bit more difficult for an adversary to
determine which keys have recently been in use.

This is safe because the key_jar cache does not use a constructor.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJames Morris <james.l.morris@oracle.com>

Each time a new speed is added, the bonding 802.3ad isn't updated. Add a
comment to remind the developer to update this driver.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The first netlink attribute (value 0) must always be defined
as none/unspec.

Because we cannot change an existing UAPI, I add a comment to point the
mistake and avoid to propagate it in a new ovs API in the future.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix messages like this:

adv7842.c:(.text+0x2edadd): undefined reference to `cec_unregister_adapter'

when CEC_CORE=m but the driver including media/cec.h is built-in. In that case
the static inlines provided in media/cec.h should be used by that driver.
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

Currently there's no way to dump the VIF table for an ipmr table other
than the default (via proc). This is a major issue when debugging ipmr
issues and in general it is good to know which interfaces are
configured. This patch adds support for RTM_GETLINK for the ipmr family
so we can dump the VIF table and the ipmr table's current config for
each table. We're protected by rtnl so no need to acquire RCU or
mrt_lock.
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a new static FDB is added to the bridge a notification is sent to
the driver for offload. In case of successful offload the driver should
notify the bridge back, which in turn should mark the FDB as offloaded.

Currently, externally learned is equivalent for being offloaded which is
not correct due to the fact that FDBs which are added from user-space are
also marked as externally learned. In order to specify if an FDB was
successfully offloaded a new flag is introduced.
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the bridge doesn't notify the underlying devices about new
FDBs learned. The FDB sync is placed on the switchdev notifier chain
because devices may potentially learn FDB that are not directly related
to their ports, for example:

1. Mixed SW/HW bridge - FDBs that point to the ASICs external devices
                        should be offloaded as CPU traps in order to
			perform forwarding in slow path.
2. EVPN - Externally learned FDBs for the vtep device.

Notification is sent only about static FDB add/del. This is done due
to fact that currently this is the only scenario supported by switch
drivers.
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: NIvan Vecera <ivecera@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is done as a preparation stage before setting the bridge port flags
from the bridge code. Currently the device can be queried for the bridge
flags state, but the querier cannot distinguish if the flag is disabled
or if it is not supported at all. Thus, add new attr and a bit-mask which
include information regarding the support on a per-flag basis.

Drivers that support bridge offload but not support bridge flags should
return zeroed bitmask.
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NIvan Vecera <ivecera@redhat.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NIvan Vecera <ivecera@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DRAM supply shortage and poor memory pressure tracking in TCP
stack makes any change in SO_SNDBUF/SO_RCVBUF (or equivalent autotuning
limits) and tcp_mem[] quite hazardous.

TCPMemoryPressures SNMP counter is an indication of tcp_mem sysctl
limits being hit, but only tracking number of transitions.

If TCP stack behavior under stress was perfect :
1) It would maintain memory usage close to the limit.
2) Memory pressure state would be entered for short times.

We certainly prefer 100 events lasting 10ms compared to one event
lasting 200 seconds.

This patch adds a new SNMP counter tracking cumulative duration of
memory pressure events, given in ms units.

$ cat /proc/sys/net/ipv4/tcp_mem
3088    4117    6176
$ grep TCP /proc/net/sockstat
TCP: inuse 180 orphan 0 tw 2 alloc 234 mem 4140
$ nstat -n ; sleep 10 ; nstat |grep Pressure
TcpExtTCPMemoryPressures        1700
TcpExtTCPMemoryPressuresChrono  5209

v2: Used EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL() as David
instructed.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Linu Cherian reported a WARN in cleanup_srcu_struct() when shutting
down a guest running iperf on a VFIO assigned device.  This happens
because irqfd_wakeup() calls srcu_read_lock(&kvm->irq_srcu) in interrupt
context, while a worker thread does the same inside kvm_set_irq().  If the
interrupt happens while the worker thread is executing __srcu_read_lock(),
updates to the Classic SRCU ->lock_count[] field or the Tree SRCU
->srcu_lock_count[] field can be lost.

The docs say you are not supposed to call srcu_read_lock() and
srcu_read_unlock() from irq context, but KVM interrupt injection happens
from (host) interrupt context and it would be nice if SRCU supported the
use case.  KVM is using SRCU here not really for the "sleepable" part,
but rather due to its IPI-free fast detection of grace periods.  It is
therefore not desirable to switch back to RCU, which would effectively
revert commit 719d93cd ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING",
2014-01-16).

However, the docs are overly conservative.  You can have an SRCU instance
only has users in irq context, and you can mix process and irq context
as long as process context users disable interrupts.  In addition,
__srcu_read_unlock() actually uses this_cpu_dec() on both Tree SRCU and
Classic SRCU.  For those two implementations, only srcu_read_lock()
is unsafe.

When Classic SRCU's __srcu_read_unlock() was changed to use this_cpu_dec(),
in commit 5a41344a ("srcu: Simplify __srcu_read_unlock() via
this_cpu_dec()", 2012-11-29), __srcu_read_lock() did two increments.
Therefore it kept __this_cpu_inc(), with preempt_disable/enable in
the caller.  Tree SRCU however only does one increment, so on most
architectures it is more efficient for __srcu_read_lock() to use
this_cpu_inc(), and any performance differences appear to be down in
the noise.

Cc: stable@vger.kernel.org
Fixes: 719d93cd ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING")
Reported-by: NLinu Cherian <linuc.decode@gmail.com>
Suggested-by: NLinu Cherian <linuc.decode@gmail.com>
Cc: kvm@vger.kernel.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

Roopa reported attempts to delete a bond device that is referenced in a
multipath route is hanging:

$ ifdown bond2    # ifupdown2 command that deletes virtual devices
unregister_netdevice: waiting for bond2 to become free. Usage count = 2

Steps to reproduce:
    echo 1 > /proc/sys/net/ipv6/conf/all/ignore_routes_with_linkdown
    ip link add dev bond12 type bond
    ip link add dev bond13 type bond
    ip addr add 2001:db8:2::0/64 dev bond12
    ip addr add 2001:db8:3::0/64 dev bond13
    ip route add 2001:db8:33::0/64 nexthop via 2001:db8:2::2 nexthop via 2001:db8:3::2
    ip link del dev bond12
    ip link del dev bond13

The root cause is the recent change to keep routes on a linkdown. Update
the check to detect when the device is unregistering and release the
route for that case.

Fixes: a1a22c12 ("net: ipv6: Keep nexthop of multipath route on admin down")
Reported-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>