Driver for the Microchip MRF24J40 802.15.4 WPAN module.
Signed-off-by: NAlan Ott <alan@signal11.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Stephen Rothwell says:

====================
After merging the final tree, today's linux-next build (powerpc
ppc44x_defconfig) failed like this:

net/built-in.o: In function `tcp_fastopen_ctx_free':
tcp_fastopen.c:(.text+0x5cc5c): undefined reference to `crypto_destroy_tfm'
net/built-in.o: In function `tcp_fastopen_reset_cipher':
(.text+0x5cccc): undefined reference to `crypto_alloc_base'
net/built-in.o: In function `tcp_fastopen_reset_cipher':
(.text+0x5cd6c): undefined reference to `crypto_destroy_tfm'

Presumably caused by commit 10467163 ("tcp: TCP Fast Open Server -
header & support functions") from the net-next tree.  I assume that some
dependency on the CRYPTO infrastructure is missing.

I have reverted commit 1bed966c ("Merge branch
'tcp_fastopen_server'") for today.
====================
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using list_move_tail() instead of list_del() + list_add_tail().

spatch with a semantic match is used to found this problem.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

usbnet_start_xmit() is always called with a valid skb
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use hash table to store ports of datapath. Allow 64K ports per switch.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NJesse Gross <jesse@nicira.com>

Use proportional rate reduction (PRR) algorithm to reduce cwnd in CWR state,
in addition to Recovery state. Retire the current rate-halving in CWR.
When losses are detected via ACKs in CWR state, the sender enters Recovery
state but the cwnd reduction continues and does not restart.

Rename and refactor cwnd reduction functions since both CWR and Recovery
use the same algorithm:
tcp_init_cwnd_reduction() is new and initiates reduction state variables.
tcp_cwnd_reduction() is previously tcp_update_cwnd_in_recovery().
tcp_ends_cwnd_reduction() is previously  tcp_complete_cwr().

The rate halving functions and logic such as tcp_cwnd_down(), tcp_min_cwnd(),
and the cwnd moderation inside tcp_enter_cwr() are removed. The unused
parameter, flag, in tcp_cwnd_reduction() is also removed.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To prepare replacing rate halving with PRR algorithm in CWR state.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To prepare replacing rate halving with PRR algorithm in CWR state.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rx_urb_size is set to the same value for every device
supported by this driver.  No need to keep a per-device
data structure to do that. Replacing with a macro constant.

This was the last device specific info, and removing it
allows us to delete the sierra_net_info_data struct.
Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This merges (3f509c68 netfilter: nf_nat_sip: fix incorrect handling
of EBUSY for RTCP expectation) to Patrick McHardy's IPv6 NAT changes.

Despite being just a few bytes of code, they should still have proper
annotations.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Since 'list_for_each_continue_rcu' has already been replaced by
'list_for_each_entry_continue_rcu', pass 'list_head' to nf_queue() as a
parameter can not benefit us any more.

This patch will replace 'list_head' with 'nf_hook_ops' as the parameter of
nf_queue() and __nf_queue() to save code.
Signed-off-by: NMichael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Since 'list_for_each_continue_rcu' has already been replaced by
'list_for_each_entry_continue_rcu', pass 'list_head' to nf_iterate() as a
parameter can not benefit us any more.

This patch will replace 'list_head' with 'nf_hook_ops' as the parameter of
nf_iterate() to save code.
Signed-off-by: NMichael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

It was scheduled to be removed for a long time.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netfilter@vger.kernel.org
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch adds the new nf_ct_timeout_lookup function to encapsulate
the timeout policy attachment that is called in the nf_conntrack_in
path.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch adds xt_ct_set_helper and xt_ct_set_timeout to reduce
the size of xt_ct_tg_check.

This aims to improve code mantainability by splitting xt_ct_tg_check
in smaller chunks.

Suggested by Eric Dumazet.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch fixes compilation warnings in xt_socket with gcc-4.7.

In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:265:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:265:9: note: ‘dport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:264:27: note: ‘saddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:264:19: note: ‘daddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_match.isra.4’:
include/net/netfilter/nf_tproxy_core.h:75:2: warning: ‘protocol’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:113:5: note: ‘protocol’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:45: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:112:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:106:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:112:9: note: ‘dport’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:15: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:111:16: note: ‘saddr’ was declared here
In file included from include/net/tcp.h:37:0,
                 from net/netfilter/xt_socket.c:17:
include/net/inet_hashtables.h:356:15: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:111:9: note: ‘daddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:268:16: note: ‘sport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:268:9: note: ‘dport’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:267:27: note: ‘saddr’ was declared here
In file included from net/netfilter/xt_socket.c:22:0:
include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/netfilter/xt_socket.c:267:19: note: ‘daddr’ was declared here
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Before, it was impossible to remove a wpan device which had lowpan
attached to it.
Signed-off-by: NAlan Ott <alan@signal11.us>
Signed-off-by: NDavid S. Miller <davem@tempietto.lan>

Since lowpan_process_data() modifies the skb (by calling skb_pull()), we
need our own copy so that it doesn't affect the data received by other
protcols (in this case, af_ieee802154).
Signed-off-by: NAlan Ott <alan@signal11.us>
Signed-off-by: NDavid S. Miller <davem@tempietto.lan>

Jerry Chu says:

====================
This patch series provides the server (passive open) side code
for TCP Fast Open. Together with the earlier client side patches
it completes the TCP Fast Open implementation.

The server side Fast Open code accepts data carried in the SYN
packet with a valid Fast Open cookie, and passes it to the
application right away, allowing application to send back response
data, all before TCP's 3-way handshake finishes.

A simple cookie scheme together with capping the number of
outstanding TFO requests (still in TCP_SYN_RECV state) to a limit
per listener forms the main line of defense against spoofed SYN
attacks.

For more details about TCP Fast Open see our IETF internet draft
at http://www.ietf.org/id/draft-ietf-tcpm-fastopen-01.txt
and a research paper at
http://conferences.sigcomm.org/co-next/2011/papers/1569470463.pdf

A prototype implementation was first developed by Sivasankar
Radhakrishnan (sivasankar@cs.ucsd.edu).

A patch based on an older version of Linux kernel has been
undergoing internal tests at Google for the past few months.

Jerry Chu (3):
  tcp: TCP Fast Open Server - header & support functions
  tcp: TCP Fast Open Server - support TFO listeners
  tcp: TCP Fast Open Server - main code path
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the main processing path to complete the TFO server
patches.

A TFO request (i.e., SYN+data packet with a TFO cookie option) first
gets processed in tcp_v4_conn_request(). If it passes the various TFO
checks by tcp_fastopen_check(), a child socket will be created right
away to be accepted by applications, rather than waiting for the 3WHS
to finish.

In additon to the use of TFO cookie, a simple max_qlen based scheme
is put in place to fend off spoofed TFO attack.

When a valid ACK comes back to tcp_rcv_state_process(), it will cause
the state of the child socket to switch from either TCP_SYN_RECV to
TCP_ESTABLISHED, or TCP_FIN_WAIT1 to TCP_FIN_WAIT2. At this time
retransmission will resume for any unack'ed (data, FIN,...) segments.
Signed-off-by: NH.K. Jerry Chu <hkchu@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch builds on top of the previous patch to add the support
for TFO listeners. This includes -

1. allocating, properly initializing, and managing the per listener
fastopen_queue structure when TFO is enabled

2. changes to the inet_csk_accept code to support TFO. E.g., the
request_sock can no longer be freed upon accept(), not until 3WHS
finishes

3. allowing a TCP_SYN_RECV socket to properly poll() and sendmsg()
if it's a TFO socket

4. properly closing a TFO listener, and a TFO socket before 3WHS
finishes

5. supporting TCP_FASTOPEN socket option

6. modifying tcp_check_req() to use to check a TFO socket as well
as request_sock

7. supporting TCP's TFO cookie option

8. adding a new SYN-ACK retransmit handler to use the timer directly
off the TFO socket rather than the listener socket. Note that TFO
server side will not retransmit anything other than SYN-ACK until
the 3WHS is completed.

The patch also contains an important function
"reqsk_fastopen_remove()" to manage the somewhat complex relation
between a listener, its request_sock, and the corresponding child
socket. See the comment above the function for the detail.
Signed-off-by: NH.K. Jerry Chu <hkchu@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds all the necessary data structure and support
functions to implement TFO server side. It also documents a number
of flags for the sysctl_tcp_fastopen knob, and adds a few Linux
extension MIBs.

In addition, it includes the following:

1. a new TCP_FASTOPEN socket option an application must call to
supply a max backlog allowed in order to enable TFO on its listener.

2. A number of key data structures:
"fastopen_rsk" in tcp_sock - for a big socket to access its
request_sock for retransmission and ack processing purpose. It is
non-NULL iff 3WHS not completed.

"fastopenq" in request_sock_queue - points to a per Fast Open
listener data structure "fastopen_queue" to keep track of qlen (# of
outstanding Fast Open requests) and max_qlen, among other things.

"listener" in tcp_request_sock - to point to the original listener
for book-keeping purpose, i.e., to maintain qlen against max_qlen
as part of defense against IP spoofing attack.

3. various data structure and functions, many in tcp_fastopen.c, to
support server side Fast Open cookie operations, including
/proc/sys/net/ipv4/tcp_fastopen_key to allow manual rekeying.
Signed-off-by: NH.K. Jerry Chu <hkchu@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This one includes a 8168. Not to be confused with the sky2 driven
one whose PCI vendor and device ID are the same.
Reported-by: NNeyuki Inaya <in@joblog.ru>
Signed-off-by: NFrancois Romieu <romieu@fr.zoreil.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, all the time limits in the bonding ARP monitor are in
multiples of arp_interval -- the time interval at which the ARP
monitor is periodically scheduled.

With a fast network round-trip and a little scheduling latency
of the ARP monitor work, a limit of n*delta_in_ticks may
effectively mean (n-1)*delta_in_ticks.

This is fatal in case of n==1  (the link will stay down
forever) and makes the behaviour non-deterministic in all the
other cases.

Add a delta_in_ticks/2 time slack to all the time limits.
Signed-off-by: NJiri Bohac <jbohac@suse.cz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__ipv6_regen_rndid no longer returns anything other than 0
so there's no point in verifying what it returns
Signed-off-by: NSorin Dumitru <sdumitru@ixiacom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb_needs_linearize() does not check highmem DMA as it does not call
illegal_highdma() anymore, so there is no need to mention highmem DMA here.

(Indeed, ~NETIF_F_SG flag, which is checked in skb_needs_linearize(), can
be set when illegal_highdma() returns true, and we are assured that
illegal_highdma() is invoked prior to skb_needs_linearize() as
skb_needs_linearize() is a static method called only once.
But ~NETIF_F_SG can be set not only there in this same invocation path.
It can also be set when can_checksum_protocol() returns false).

see commit 02932ce9,
Convert skb_need_linearize() to use precomputed features.
Signed-off-by: NRami Rosen <rosenr@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In ipv4_mtu there is some logic where we are testing for a non-zero value
and a timer expiration, then setting the value to zero, and then testing if
the value is zero we set it to a value based on the dst.  Instead of
bothering with the extra steps it is easier to just cleanup the logic so
that we set it to the dst based value if it is zero or if the timer has
expired.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>

At commit 07d106d0, Linus pointed out that ENOIOCTLCMD should be
translated as ENOTTY to user mode.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: NWanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch moves calls to ioremap and request_mem_region to
devm_request_and_ioremap call.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes bus_id from mdio platform data, The reason to remove
bus_id is, stmmac mdio bus_id is always same as stmmac bus-id, so there
is no point in passing this in different variable.
Also stmmac ethernet driver connects to phy with bus_id passed its
platform data.
So, having single bus-id is much simpler.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes stmmac_pltfr_remove function, which is broken because,
it is accessing plat variable via freed memory priv pointer which gets
freed by free_netdev called from stmmac_dvr_remove.

In short this patch caches the plat pointer in local variable before
calling stmmac_dvr_remove to prevent code accessing freed memory.

Without this patch any attempt to remove the stmmac device will fail as
below:

Unregistering eth 0 ...
Unable to handle kernel paging request at virtual address 6b6b6bab
pgd = de5dc000
[6b6b6bab] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP
Modules linked in: cdev(O+)
CPU: 0    Tainted: G           O  (3.3.1_stm24_0210-b2000+ #25)
PC is at stmmac_pltfr_remove+0x2c/0xa0
LR is at stmmac_pltfr_remove+0x28/0xa0
pc : [<c01b8908>]    lr : [<c01b8904>]    psr: 60000013
sp : def6be78  ip : de6c5a00  fp : 00000000
r10: 00000028  r9 : c082d81d  r8 : 00000001
r7 : de65a600  r6 : df81b240  r5 : c0413fd8  r4 : 00000000
r3 : 6b6b6b6b  r2 : def6be6c  r1 : c0355e2b  r0 : 00000020
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 5e5dc04a  DAC: 00000015
Process insmod (pid: 738, stack limit = 0xdef6a2f0)
Stack: (0xdef6be78 to 0xdef6c000)
be60:                                                       c0413fe0
c0403658
be80: c0400bb0 c019270c c01926f8 c0191478 00000000 c0414014 c0413fe0
c01914d8
bea0: 00000000 c0413fe0 df8045d0 c019109c c0413fe0 c0400bf0 c0413fd8
c018f04c
bec0: 00000000 bf000000 c0413fd8 c01929a0 c0413fd8 bf000000 00000000
c0192bfc
bee0: bf00009c bf000014 def6a000 c000859c 00000000 00000001 bf00009c
bf00009c
bf00: 00000001 bf00009c 00000001 bf0000e4 de65a600 00000001 c082d81d
c0058cd0
bf20: bf0000a8 c004fbd8 c0056414 c082d815 c02aea20 bf0001f0 00b0b008
e0846208
bf40: c03ec8a0 e0846000 0000db0d e0850604 e08504de e0853a24 00000204
000002d4
bf60: 00000000 00000000 0000001c 0000001d 00000009 00000000 00000006
00000000
bf80: 00000003 f63d4e2e 0000db0d bef02ed8 00000080 c000d2e8 def6a000
00000000
bfa0: 00000000 c000d140 f63d4e2e 0000db0d 00b0b018 0000db0d 00b0b008
b6f4f298
bfc0: f63d4e2e 0000db0d bef02ed8 00000080 00000003 00000000 00010000
00000000
bfe0: 00b0b008 bef02c64 00008d20 b6ef3784 60000010 00b0b018 5a5a5a5a
5a5a5a5a
[<c01b8908>] (stmmac_pltfr_remove+0x2c/0xa0) from [<c019270c>]
(platform_drv_remove+0x14/0x18)
[<c019270c>] (platform_drv_remove+0x14/0x18) from [<c0191478>]
(__device_release_driver+0x64/0xa4)
[<c0191478>] (__device_release_driver+0x64/0xa4) from [<c01914d8>]
(device_release_driver+0x20/0x2c)
[<c01914d8>] (device_release_driver+0x20/0x2c) from [<c019109c>]
(bus_remove_device+0xcc/0xdc)
[<c019109c>] (bus_remove_device+0xcc/0xdc) from [<c018f04c>]
(device_del+0x104/0x160)
[<c018f04c>] (device_del+0x104/0x160) from [<c01929a0>]
(platform_device_del+0x18/0x58)
[<c01929a0>] (platform_device_del+0x18/0x58) from [<c0192bfc>]
(platform_device_unregister+0xc/0x18)
[<c0192bfc>] (platform_device_unregister+0xc/0x18) from [<bf000014>]
(r_init+0x14/0x2c [cdev])
[<bf000014>] (r_init+0x14/0x2c [cdev]) from [<c000859c>]
(do_one_initcall+0x90/0x160)
[<c000859c>] (do_one_initcall+0x90/0x160) from [<c0058cd0>]
(sys_init_module+0x15c4/0x1794)
[<c0058cd0>] (sys_init_module+0x15c4/0x1794) from [<c000d140>]
(ret_fast_syscall+0x0/0x30)
Code: e1a04000 e59f0070 eb039b65 e59636e4 (e5933040)
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a basic check in stmmac_mdio_unregister to see if mdio
bus registeration for this driver was actually sucessfull or not.

Use case here is, if BSP considers using mdio-gpio bus along with stmmac
driver by passing mdio_bus_data as NULL in platform data.
Call to stmmac_mdio_register with mdio_bus_data as NULL returns 0, which
is a considered sucessfull call form stmmac. Then again when we unload
the driver we just call stmmac_mdio_unregister, this is were the actual
problem is stmmac-mdio code dont really know at this instance of calling
that stmmac_mdio_register was actually successful.

So Adding a check in stmmac_mdio_unregister is always safe.

Without this patch stmmac driver calls stmmac_mdio_register from
stmmac_release which Segfaults as mii bus was never registered at the
first point.

Originally the this bug was found when unloading an stmmac driver
instance which uses mdio-gpio for smi access.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The callback function of call_rcu() just calls a kfree(), so we
can use kfree_rcu() instead of call_rcu() + callback function.

spatch with a semantic match is used to found this problem.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Return -EINVAL rather than 0 given an invalid "mode" parameter.
Signed-off-by: NXi Wang <xi.wang@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>