When application sends an RDS RDMA composite message consist of
RDMA transfer to be followed up by non RDMA payload, it expect to
be notified *only* when the full message gets delivered. RDS RDMA
notification doesn't behave this way though.

Thanks to Venkat for debug and root casuing the issue
where only first part of the message(RDMA) was
successfully delivered but remainder payload delivery failed.
In that case, application should not be notified with
a false positive of message delivery success.

Fix this case by making sure the user gets notified only after
the full message delivery.
Reviewed-by: NVenkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

The first message to a remote node should prompt a new
connection even if it is RDMA operation. For RDMA operation
the MR mapping can fail because connections is not yet up.

Since the connection establishment is asynchronous,
we make sure the map failure because of unavailable
connection reach to the user by appropriate error code.
Before returning to the user, lets trigger the connection
so that its ready for the next retry.
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

Fixes below warnings:
warning: symbol 'rds_send_probe' was not declared. Should it be static?
warning: symbol 'rds_send_ping' was not declared. Should it be static?
warning: symbol 'rds_tcp_accept_one_path' was not declared. Should it be static?
warning: symbol 'rds_walk_conn_path_info' was not declared. Should it be static?
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

The RDS transport has to be able to distinguish between
two types of failure events:
(a) when the transport fails (e.g., TCP connection reset)
    but the RDS socket/connection layer on both sides stays
    the same
(b) when the peer's RDS layer itself resets (e.g., due to module
    reload or machine reboot at the peer)
In case (a) both sides must reconnect and continue the RDS messaging
without any message loss or disruption to the message sequence numbers,
and this is achieved by rds_send_path_reset().

In case (b) we should reset all rds_connection state to the
new incarnation of the peer. Examples of state that needs to
be reset are next expected rx sequence number from, or messages to be
retransmitted to, the new incarnation of the peer.

To achieve this, the RDS handshake probe added as part of
commit 5916e2c1 ("RDS: TCP: Enable multipath RDS for TCP")
is enhanced so that sender and receiver of the RDS ping-probe
will add a generation number as part of the RDS_EXTHDR_GEN_NUM
extension header. Each peer stores local and remote generation
numbers as part of each rds_connection. Changes in generation
number will be detected via incoming handshake probe ping
request or response and will allow the receiver to reset rds_connection
state.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use RDS probe-ping to compute how many paths may be used with
the peer, and to synchronously start the multiple paths. If mprds is
supported, hash outgoing traffic to one of multiple paths in rds_sendmsg()
when multipath RDS is supported by the transport.

CC: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refactor code to avoid separate indirections for single-path
and multipath transports. All transports (both single and mp-capable)
will get a pointer to the rds_conn_path, and can trivially derive
the rds_connection from the ->cp_conn.
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit changes rds_conn_shutdown to take a rds_conn_path *
argument, allowing it to shutdown paths other than c_path[0] for
MP-capable transports.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_conn_path_connect_if_down() works on the rds_conn_path
that it is passed. Callers who are not t_m_capable may continue
calling rds_conn_connect_if_down, which will invoke
rds_conn_path_connect_if_down() with the default c_path[0].
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit allows rds_send_pong() callers to send back
the rds pong message on some path other than c_path[0] by
passing in a struct rds_conn_path * argument.  It also
removes the last dependency on the #defines in rds_single.h
from send.c
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Explicitly set up rds_conn_path, either from i_conn_path (for
MP capable transpots) or as c_path[0], and use this in
rds_send_drop_to()
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass a struct rds_conn_path to rds_send_xmit so that MP capable
transports can transmit packets on something other than c_path[0].
The eventual goal for MP capable transports is to hash the rds
socket to a path based on the bound local address/port, and use
this path as the argument to rds_send_xmit()
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the rds_conn_path to rds_send_queue_rm, and use it to initialize
the i_conn_path field in struct rds_incoming. This commit also makes
rds_send_queue_rm() MP capable, because it now takes locks
specific to the rds_conn_path passed in, instead of defaulting to
the c_path[0] based defines from rds_single_path.h
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only caller of rds_send_get_message() was
rds_iw_send_cq_comp_handler() which was removed as part of
commit dcdede04 ("RDS: Drop stale iWARP RDMA transport"),
so remove rds_send_get_message() for the same reason.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_send_path_drop_acked() is the path-specific version of
rds_send_drop_acked() to be invoked by MP capable callers.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_send_path_reset() is the path specific version of rds_send_reset()
intended for MP capable callers.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for multipath RDS, split the rds_connection
structure into a base structure, and a per-path struct rds_conn_path.
The base structure tracks information and locks common to all
paths. The workqs for send/recv/shutdown etc are tracked per
rds_conn_path. Thus the workq callbacks now work with rds_conn_path.

This commit allows for one rds_conn_path per rds_connection, and will
be extended into multiple conn_paths in  subsequent commits.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we switch a connection's sockets in rds_tcp_rest_callbacks,
any partially sent datagram must be retransmitted on the new
socket so that the receiver can correctly reassmble the RDS
datagram. Use rds_send_reset() which is designed for this purpose.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sasha's found a NULL pointer dereference in the RDS connection code when
sending a message to an apparently unbound socket.  The problem is caused
by the code checking if the socket is bound in rds_sendmsg(), which checks
the rs_bound_addr field without taking a lock on the socket.  This opens a
race where rs_bound_addr is temporarily set but where the transport is not
in rds_bind(), leading to a NULL pointer dereference when trying to
dereference 'trans' in __rds_conn_create().

Vegard wrote a reproducer for this issue, so kindly ask him to share if
you're interested.

I cannot reproduce the NULL pointer dereference using Vegard's reproducer
with this patch, whereas I could without.

Complete earlier incomplete fix to CVE-2015-6937:

  74e98eb0 ("RDS: verify the underlying transport exists before creating a connection")

Cc: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org
Reviewed-by: NVegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: NSasha Levin <sasha.levin@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NQuentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sowmini found hang with rds-ping while testing RDS over TCP. Its
a corner case and doesn't happen always. The issue is not reproducible
with IB transport. Its clear from below dump why we see it with RDS TCP.

 [<ffffffff8153b7e5>] do_tcp_setsockopt+0xb5/0x740
 [<ffffffff8153bec4>] tcp_setsockopt+0x24/0x30
 [<ffffffff814d57d4>] sock_common_setsockopt+0x14/0x20
 [<ffffffffa096071d>] rds_tcp_xmit_prepare+0x5d/0x70 [rds_tcp]
 [<ffffffffa093b5f7>] rds_send_xmit+0xd7/0x740 [rds]
 [<ffffffffa093bda2>] rds_send_pong+0x142/0x180 [rds]
 [<ffffffffa0939d34>] rds_recv_incoming+0x274/0x330 [rds]
 [<ffffffff810815ae>] ? ttwu_queue+0x11e/0x130
 [<ffffffff814dcacd>] ? skb_copy_bits+0x6d/0x2c0
 [<ffffffffa0960350>] rds_tcp_data_recv+0x2f0/0x3d0 [rds_tcp]
 [<ffffffff8153d836>] tcp_read_sock+0x96/0x1c0
 [<ffffffffa0960060>] ? rds_tcp_recv_init+0x40/0x40 [rds_tcp]
 [<ffffffff814d6a90>] ? sock_def_write_space+0xa0/0xa0
 [<ffffffffa09604d1>] rds_tcp_data_ready+0xa1/0xf0 [rds_tcp]
 [<ffffffff81545249>] tcp_data_queue+0x379/0x5b0
 [<ffffffffa0960cdb>] ? rds_tcp_write_space+0xbb/0x110 [rds_tcp]
 [<ffffffff81547fd2>] tcp_rcv_established+0x2e2/0x6e0
 [<ffffffff81552602>] tcp_v4_do_rcv+0x122/0x220
 [<ffffffff81553627>] tcp_v4_rcv+0x867/0x880
 [<ffffffff8152e0b3>] ip_local_deliver_finish+0xa3/0x220

This happens because rds_send_xmit() chain wants to take
sock_lock which is already taken by tcp_v4_rcv() on its
way to rds_tcp_data_ready(). Commit db6526dc ("RDS: use
rds_send_xmit() state instead of RDS_LL_SEND_FULL") which
was trying to opportunistically finish the send request
in same thread context.

But because of above recursive lock hang with RDS TCP,
the send work from rds_send_pong() needs to deferred to
worker to avoid lock up. Given RDS ping is more of connectivity
test than performance critical path, its should be ok even
for transport like IB.
Reported-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to what we did with receive CQ completion handling, we split
the transmit completion handler so that it lets us implement batched
work completion handling.

We re-use the cq_poll routine and makes use of RDS_IB_SEND_OP to
identify the send vs receive completion event handler invocation.
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

In Transport indepedent rds_sendmsg(), we shouldn't make decisions based
on RDS_LL_SEND_FULL which is used to manage the ring for RDMA based
transports. We can safely issue rds_send_xmit() and the using its
return value take decision on deferred work. This will also fix
the scenario where at times we are seeing connections stuck with
the LL_SEND_FULL bit getting set and never cleared.

We kick krdsd after any time we see -ENOMEM or -EAGAIN from the
ring allocation code.
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

Current process gives up if its send work over the batch limit.
The work queue will get  kicked to finish off any other requests.
This fixes remainder condition from commit 443be0e5 ("RDS: make
sure not to loop forever inside rds_send_xmit").

The restart condition is only for the case where we reached to
over_batch code for some other reason so just retrying again
before giving up.

While at it, make sure we use already available 'send_batch_count'
parameter instead of magic value. The batch count threshold value
of 1024 came via commit 443be0e5 ("RDS: make sure not to loop
forever inside rds_send_xmit"). The idea is to process as big a
batch as we can but at the same time we don't hold other waiting
processes for send. Hence back-off after the send_batch_count
limit (1024) to avoid soft-lock ups.
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>

rds_send_queue_rm() allows for the "current datagram" being queued
to exceed SO_SNDBUF thresholds by checking bytes queued without
counting in length of current datagram. (Since sk_sndbuf is set
to twice requested SO_SNDBUF value as a kernel heuristic this
is usually fine!)

If this "current datagram" squeezing past the threshold is itself
many times the size of the sk_sndbuf threshold itself then even
twice the SO_SNDBUF does not save us and it gets queued but
cannot be transmitted. Threads block and deadlock and device
becomes unusable. The check for this datagram not exceeding
SNDBUF thresholds (EMSGSIZE) is not done on this datagram as
that check is only done if queueing attempt fails.
(Datagrams that follow this datagram fail queueing attempts, go
through the check and eventually trip EMSGSIZE error but zero
length datagrams silently fail!)

This fix moves the check for datagrams exceeding SNDBUF limits
before any processing or queueing is attempted and returns EMSGSIZE
early in the rds_sndmsg() code. This change also ensures that all
datagrams get checked for exceeding SNDBUF/sk_sndbuf size limits
and the large datagrams that exceed those limits do not get to
rds_send_queue_rm() code for processing.
Signed-off-by: NMukesh Kacker <mukesh.kacker@oracle.com>
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_send_drop_to() is used during socket tear down to find all the
messages on the socket and flush them .  It can race with the
acking code unless it takes the m_rs_lock on each and every message.

This plugs a hole where we didn't take m_rs_lock on any message that
didn't have the RDS_MSG_ON_CONN set.  Taking m_rs_lock avoids
double frees and other memory corruptions as the ack code trusts
the message m_rs pointer on a socket that had actually been freed.

We must take m_rs_lock to access m_rs.  Because of lock nesting and
rs access, we also need to acquire rs_lock.
Reviewed-by: NAjaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rds_send_xmit() marks the rds message map flag after
xmit_[rdma/atomic]() which is clearly wrong.  We need
to maintain the ownership between transport and rds.

Also take care of error path.
Reviewed-by: NAjaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ensure we don't keep sending the data if the link is congested.
Reviewed-by: NAjaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Signed-off-by: NSantosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Open the sockets calling sock_create_kern() with the correct struct net
pointer, and use that struct net pointer when verifying the
address passed to rds_bind().
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a determined set of concurrent senders keep the send queue full,
we can loop forever inside rds_send_xmit.  This fix has two parts.

First we are dropping out of the while(1) loop after we've processed a
large batch of messages.

Second we add a generation number that gets bumped each time the
xmit bit lock is acquired.  If someone else has jumped in and
made progress in the queue, we skip our goto restart.

Original patch by Chris Mason.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

I got a report of a double free happening at RDS slab cache. One
suspicion was that may be somewhere we were doing a sock_hold/sock_put
on an already freed sock. Thus after providing a kernel with the
following change:

 static inline void sock_hold(struct sock *sk)
 {
-       atomic_inc(&sk->sk_refcnt);
+       if (!atomic_inc_not_zero(&sk->sk_refcnt))
+               WARN(1, "Trying to hold sock already gone: %p (family: %hd)\n",
+                       sk, sk->sk_family);
 }

The warning successfuly triggered:

Trying to hold sock already gone: ffff81f6dda61280 (family: 21)
WARNING: at include/net/sock.h:350 sock_hold()
Call Trace:
<IRQ>  [<ffffffff8adac135>] :rds:rds_send_remove_from_sock+0xf0/0x21b
[<ffffffff8adad35c>] :rds:rds_send_drop_acked+0xbf/0xcf
[<ffffffff8addf546>] :rds_rdma:rds_ib_recv_tasklet_fn+0x256/0x2dc
[<ffffffff8009899a>] tasklet_action+0x8f/0x12b
[<ffffffff800125a2>] __do_softirq+0x89/0x133
[<ffffffff8005f30c>] call_softirq+0x1c/0x28
[<ffffffff8006e644>] do_softirq+0x2c/0x7d
[<ffffffff8006e4d4>] do_IRQ+0xee/0xf7
[<ffffffff8005e625>] ret_from_intr+0x0/0xa
<EOI>

Looking at the call chain above, the only way I think this would be
possible is if somewhere we already released the same socket->sock which
is assigned to the rds_message at rds_send_remove_from_sock. Which seems
only possible to happen after the tear down done on rds_release.

rds_release properly calls rds_send_drop_to to drop the socket from any
rds_message, and some proper synchronization is in place to avoid race
with rds_send_drop_acked/rds_send_remove_from_sock. However, I still see
a very narrow window where it may be possible we touch a sock already
released: when rds_release races with rds_send_drop_acked, we check
RDS_MSG_ON_CONN to avoid cleanup on the same rds_message, but in this
specific case we don't clear rm->m_rs. In this case, it seems we could
then go on at rds_send_drop_to and after it returns, the sock is freed
by last sock_put on rds_release, with concurrently we being at
rds_send_remove_from_sock; then at some point in the loop at
rds_send_remove_from_sock we process an rds_message which didn't have
rm->m_rs unset for a freed sock, and a possible sock_hold on an sock
already gone at rds_release happens.

This hopefully address the described condition above and avoids a double
free on "second last" sock_put. In addition, I removed the comment about
socket destruction on top of rds_send_drop_acked: we call rds_send_drop_to
in rds_release and we should have things properly serialized there, thus
I can't see the comment being accurate there.
Signed-off-by: NHerton R. Krzesinski <herton@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mostly scripted conversion of the smp_mb__* barriers.
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

This is a follow-up patch to f3d33426 ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.
Signed-off-by: NSteffen Hurrle <steffen@hurrle.net>
Suggested-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the revised patch for fixing rds-ping spinlock recursion
according to Venkat's suggestions.

RDS ping/pong over TCP feature has been broken for years(2.6.39 to
3.6.0) since we have to set TCP cork and call kernel_sendmsg() between
ping/pong which both need to lock "struct sock *sk". However, this
lock has already been hold before rds_tcp_data_ready() callback is
triggerred. As a result, we always facing spinlock resursion which
would resulting in system panic.

Given that RDS ping is only used to test the connectivity and not for
serious performance measurements, we can queue the pong transmit to
rds_wq as a delayed response.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
CC: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
CC: David S. Miller <davem@davemloft.net>
CC: James Morris <james.l.morris@oracle.com>
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

no socket layer outputs a message for this error and neither should rds.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

These files were getting access to these two via the implicit
presence of module.h everywhere.  They aren't modules, so they
don't need the full module.h inclusion though.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Since printk_ratelimit() shouldn't be used anymore (see comment in
include/linux/printk.h), replace it with printk_ratelimited()
Signed-off-by: NManuel Zerpies <manuel.f.zerpies@ww.stud.uni-erlangen.de>
Signed-off-by: NDavid S. Miller <davem@conan.davemloft.net>