Then other generic phy driver such as generic 10g phy driver can join it.
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andy Fleming <afleming@gmail.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Need an extra parameter to read or write Clause 45 PHYs, so
need a different API with the extra parameter.
Signed-off-by: Andy Fleming <afleming@gmail.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Keeping this as 0 is ok according to spec section 9.7.11
as this means the limits are according to the Tx/Rx
supported MCS x NSS bitmap. Initially we've set these as
there were concerns of interop issues but these turned out
to be false.
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
If we try to write NVM that do not exist, the function will return
uninitialized value. fixed.
Signed-off-by: Eytan Lifshitz <eytan.lifshitz@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Add an inline helper function for getting an RX packet's
length or payload length and use it throughout the code
(most of which I did using an spatch.)
While at it, adjust some code, and remove a bogus comment
from the dvm calibration code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Eran Harary <eran.harary@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
All beamformee supporting chips have the ability to support
VHT NDP in up to 4 STSs. So change the published beamformee
STS cap accordingly to 3 as it should be Nsts-1.
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
The request of SMPS issued by the Thermal Throttling code
was not reset when we disassociated - fix that.
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
It's a bit strange to treat an array as a pointer, so use proper
array indexing instead.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
If the length isn't set it means we want all the SRAM.
Also - this is perfectly valid to partially dump starting
at offset 0.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Discovered by klocwork
Array 'iwl_rate_mcs' of size 15 may use index value(s) -1
* rs.c:2562: index = iwl_hwrate_to_plcp_idx(rate)
* rs.c:2562: Result of function call 'iwl_hwrate_to_plcp_idx(rate)' is '[-1,14]'
* rs.c:2565: Array 'iwl_rate_mcs' size is 15.
* rs.c:2565: Possible attempt to access element -1 of array 'iwl_rate_mcs'.
While at it stop using index = -1 and always use IWL_RATE_INVALID
Signed-off-by: Eyal Shapira <eyalx.shapira@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Some NIC comes with more than the 4 NVM (non volative
memory) sections described in the nvm_to_read array.
These NICs usually get their NVM from an external file
fetched from userland during init.
We already parsed the file, but sent to the NIC only 4 NVM
sections whereas there could be more sections in the file.
Fix this.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Since seq_number is incremented right after using
it, so printed seq_ctrl was actually the next
one to be used.
Fix it by incrementing the seq_number only later,
before saving it.
Additionally, use the IEEE80211_SEQ_TO_SN macro
in order to print the actual sequence number.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Enabling the oscillator consumes slightly more power (100uA)
but allows to make sure that we exit from L1 on time.
Not doing so might lead to a PCIe specification violation
since we might wake up from L1 at the wrong time.
This issue has been identified on 3160 and 7260 only.
On older NICs L1 off is not enabled, on newer NICs (7265),
the issue is fixed.
When the bug occurs the user sees that the NIC has
disappeared from the PCI bridge, any access to the device
returns 0xff.
This fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=64541
and has been extensively discussed here:
http://markmail.org/thread/mfmpzqt3r333n4bo
Cc: stable@vger.kernel.org [3.10+]
Fixes: 99cd471423 ("iwlwifi: add 7000 series device configuration")
Reported-and-tested-by: wzyboy <wzyboy@wzyboy.org>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Avoid needless export of local functions
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a bunch of whole lot of namespace issues with the Broadcom bnx2x driver
found by running 'make namespacecheck'
* global variables must be prefixed with bnx2x_
naming a variable int_mode, or num_queue is invitation to disaster
* make local functions static
* move some inline's used in one file out of header
(this driver has a bad case of inline-itis)
* remove resulting dead code fallout
bnx2x_pfc_statistic,
bnx2x_emac_get_pfc_stat
bnx2x_init_vlan_mac_obj,
Looks like vlan mac support in this driver was a botch from day one
either never worked, or not implemented or missing support functions
Compile tested only.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If used 64 bit compiler GCC warns that:
drivers/net/ethernet/smsc/smc91x.c:1897:7:
warning: cast from pointer to integer of different
size [-Wpointer-to-int-cast]
This patch fixes this by changing typecast from "unsigned int" to "unsigned long"
CC: "David S. Miller" <davem@davemloft.net>
CC: Jingoo Han <jg1.han@samsung.com>
CC: netdev@vger.kernel.org
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simplify the GRE header length calculation in gre_gso_segment().
Switch to an approach that is simpler, faster, and more general. The
new approach will continue to be correct even if we add support for
the optional variable-length routing info that may be present in a GRE
header.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is not necessary at all.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tp->root is a void* pointer, no need to cast it.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcf_match_indev() is called in fast path, it is not wise to
search for a netdev by ifindex and then compare by its name,
just compare the ifindex.
Also, dev->name could be changed by user-space, therefore
the match would be always fail, but dev->ifindex could
be consistent.
BTW, this will also save some bytes from the core struct of u32.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It will be needed by the next patch.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Refactor tcf_add_notify() and factor out tcf_del_notify().
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no need to store the index separatedly
since tcf_hashinfo is allocated statically too.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The call to clamp_t() first truncates the variable signed 8 bit and as a
result, the actual clamp is a no-op.
Fixes: 0d78156eef ('p54: improve site survey')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Delete a variable that is at most only assigned to a constant, but never
used otherwise.
A simplified version of the semantic patch that fixes this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
type T;
identifier i;
constant c;
@@
-T i;
<... when != i
-i = c;
...>
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Global Transmission Timeout interrupts are generated by
the HW when transmission of a frame fails - this is done
based on the threshold programmed in the AR_GTXTO register.
Currently, even though the interrupt is enabled for all chips,
it is not handled in the driver. This patch handles GTT events
for AR9003 and above chips, checking if the MAC/BB has hung
after successive GTT interrupts crosses a threshold (5).
This can be enabled for the older chips in the AR9002 family once
appropriate HW hang checks are implemented for them.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
There is no need to do this and we can avoid
an unused variable warning when CONFIG_ATH9K_WOW is
not selected.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This would be useful when debugging RX performance issues.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Also, rename node_stat to node_aggr.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The asyncronous firmware load uses a completion struct to hold firmware
processing until the user-space routines are up and running. There is.
however, a problem in that the waiter is nevered canceled during teardown.
As a result, unloading the driver when firmware is not available causes an oops.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The asyncronous firmware load uses a completion struct to hold firmware
processing until the user-space routines are up and running. There is.
however, a problem in that the waiter is nevered canceled during teardown.
As a result, unloading the driver when firmware is not available causes an oops.
To be able to access the completion structure at teardown, it had to be moved
into the b43_wldev structure.
This patch also fixes a typo in a comment.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In https://bugzilla.kernel.org/show_bug.cgi?id=67561, a locking dependency is reported
when b43 is used with hostapd, and rfkill is used to kill the radio output.
The lockdep splat (in part) is as follows:
======================================================
[ INFO: possible circular locking dependency detected ]
3.12.0 #1 Not tainted
-------------------------------------------------------
rfkill/10040 is trying to acquire lock:
(rtnl_mutex){+.+.+.}, at: [<ffffffff8146f282>] rtnl_lock+0x12/0x20
but task is already holding lock:
(rfkill_global_mutex){+.+.+.}, at: [<ffffffffa04832ca>] rfkill_fop_write+0x6a/0x170 [rfkill]
--snip--
Chain exists of:
rtnl_mutex --> misc_mtx --> rfkill_global_mutex
The fix is to move the initialization of the hardware random number generator
outside the code range covered by the rtnl_mutex.
Reported-by: yury <urykhy@gmail.com>
Tested-by: yury <urykhy@gmail.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
It is u64 data received from firmware. Little endian to cpu
conversion is required here.
Cc: <stable@vger.kernel.org> # 3.5+
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The driver ignores BSS_CHANGED_TXPOWER changes.
Fix this by calling ACX_TX_POWER when appropriate.
Signed-off-by: Alex Gal <a.gal@motsai.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Adding new device IDs and assigning generic function/variable
names instead of using device-id specific names.
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: Nishant Sarmukadam <nishants@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Frank Huang <frankh@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Reported-by: Jan Prinsloo <janroot@gmail.com>
Tested-by: Jan Prinsloo <janroot@gmail.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The REGULATORY_CUSTOM_REG can be used during early init with
the goal of overriding the wiphy's default regulatory settings
in case the alpha2 of the device is not known. In the case that
the alpha2 becomes known lets avoid having drivers having to
clear the REGULATORY_CUSTOM_REG flag by doing it for them
when regulatory_hint() is used.
Cc: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ath wants to first apply the custom regd and only later
will it revert to not using it if an alpha2 regulatory
domain is found. Since the wireless core now enforces
usage of the REGULATORY_CUSTOM_REG strictly when
wiphy_apply_custom_regulatory() is used this makes
ath adhere to the expected behaviour but also updates
the wiphy after its done with the custom usage.
This fixes this warning:
[ 5.488733] ath: phy0: ASPM enabled: 0x43
[ 5.488735] ath: EEPROM regdomain: 0x0
[ 5.488736] ath: EEPROM indicates default country code should be used
[ 5.488736] ath: doing EEPROM country->regdmn map search
[ 5.488737] ath: country maps to regdmn code: 0x3a
[ 5.488737] ath: Country alpha2 being used: US
[ 5.488738] ath: Regpair used: 0x3a
[ 5.488738] ------------[ cut here ]------------
[ 5.488745] WARNING: CPU: 0 PID: 161 at
/home/sujith/dev/wireless-testing/net/wireless/reg.c:1361
wiphy_apply_custom_regulatory+0x17a/0x1b0 [cfg80211]()
[ 5.488746] wiphy should have REGULATORY_CUSTOM_REG
The wireless core can *later* lift this flag for us for when
using the regulatory_hint() to make this fix more generic.
Reported-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
GRO layer has a limit of 8 flows being held in GRO list,
for performance reason.
When a packet comes for a flow not yet in the list,
and list is full, we immediately give it to upper
stacks, lowering aggregation performance.
With TSO auto sizing and FQ packet scheduler, this situation
happens more often.
This patch changes strategy to simply evict the oldest flow of
the list. This works better because of the nature of packet
trains for which GRO is efficient. This also has the effect
of lowering the GRO latency if many flows are competing.
Tested :
Used a 40Gbps NIC, with 4 RX queues, and 200 concurrent TCP_STREAM
netperf.
Before patch, aggregate rate is 11Gbps (while a single flow can reach
30Gbps)
After patch, line rate is reached.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jerry Chu <hkchu@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to use the native GRO handling of encapsulated protocols on
mlx4, we need to call napi_gro_receive() instead of netif_receive_skb()
unless busy polling is in action.
While we are at it, rename mlx4_en_cq_ll_polling() to
mlx4_en_cq_busy_polling()
Tested with GRE tunnel : GRO aggregation is now performed on the
ethernet device instead of being done later on gre device.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Amir Vadai <amirv@mellanox.com>
Cc: Jerry Chu <hkchu@google.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Acked-By: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes the following sparse warning:
net/ipv4/gre_offload.c:253:5: warning:
symbol 'gre_gro_complete' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
It includes:
* A new NFC driver for Marvell's 8897, and a few NCI fixes and
improvements needed to support this chipset.
* An LLCP fix for how we were setting the default MIU on a p2p link. If
there is no explicit MIU extension announced at connection time, we
must use the default one and not the one announced at LLCP link
establishement time.
* A pn544 EEPROM config update. Some of the currently EEPROM configured
values are overwriting the firmware ones while other should not be set
by the driver itself.
* Some NFC digital stack fixes and improvements. Asynchronous functions
are better documented, RF technologies and CRC functions are set upon
PSL_REQ reception, and a few minor bugs are fixed.
* Minor and miscelaneous pn533, mei_phy and port100 fixes.
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Merge tag 'nfc-next-3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-next
Samuel Ortiz <sameo@linux.intel.com> says:
"This is the first NFC pull request for 3.14
It includes:
* A new NFC driver for Marvell's 8897, and a few NCI fixes and
improvements needed to support this chipset.
* An LLCP fix for how we were setting the default MIU on a p2p link. If
there is no explicit MIU extension announced at connection time, we
must use the default one and not the one announced at LLCP link
establishement time.
* A pn544 EEPROM config update. Some of the currently EEPROM configured
values are overwriting the firmware ones while other should not be set
by the driver itself.
* Some NFC digital stack fixes and improvements. Asynchronous functions
are better documented, RF technologies and CRC functions are set upon
PSL_REQ reception, and a few minor bugs are fixed.
* Minor and miscelaneous pn533, mei_phy and port100 fixes."
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Hannes Frederic Sowa says:
====================
path mtu hardening patches
After a lot of back and forth I want to propose these changes regarding
path mtu hardening and give an outline why I think this is the best way
how to proceed:
This set contains the following patches:
* ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing
* ipv6: introduce ip6_dst_mtu_forward and protect forwarding path with it
* ipv4: introduce hardened ip_no_pmtu_disc mode
The first one switches the forwarding path of IPv4 to use the interface
mtu by default and ignore a possible discovered path mtu. It provides
a sysctl to switch back to the original behavior (see discussion below).
The second patch does the same thing unconditionally for IPv6. I don't
provide a knob for IPv6 to switch to original behavior (please see
below).
The third patch introduces a hardened pmtu mode, where only pmtu
information are accepted where the protocol is able to do more stringent
checks on the icmp piggyback payload (please see the patch commit msg
for further details).
Why is this change necessary?
First of all, RFC 1191 4. Router specification says:
"When a router is unable to forward a datagram because it exceeds the
MTU of the next-hop network and its Don't Fragment bit is set, the
router is required to return an ICMP Destination Unreachable message
to the source of the datagram, with the Code indicating
"fragmentation needed and DF set". ..."
For some time now fragmentation has been considered problematic, e.g.:
* http://www.hpl.hp.com/techreports/Compaq-DEC/WRL-87-3.pdf
* http://tools.ietf.org/search/rfc4963
Most of them seem to agree that fragmentation should be avoided because
of efficiency, data corruption or security concerns.
Recently it was shown possible that correctly guessing IP ids could lead
to data injection on DNS packets:
<https://sites.google.com/site/hayashulman/files/fragmentation-poisoning.pdf>
While we can try to completly stop fragmentation on the end host
(this is e.g. implemented via IP_PMTUDISC_INTERFACE), we cannot stop
fragmentation completly on the forwarding path. On the end host the
application has to deal with MTUs and has to choose fallback methods
if fragmentation could be an attack vector. This is already the case for
most DNS software, where a maximum UDP packet size can be configured. But
until recently they had no control over local fragmentation and could
thus emit fragmented packets.
On the forwarding path we can just try to delay the fragmentation to
the last hop where this is really necessary. Current kernel already does
that but only because routers don't receive feedback of path mtus, these are
only send back to the end host system. But it is possible to maliciously
insert path mtu inforamtion via ICMP packets which have an icmp echo_reply
payload, because we cannot validate those notifications against local
sockets. DHCP clients which establish an any-bound RAW-socket could also
start processing unwanted fragmentation-needed packets.
Why does IPv4 has a knob to revert to old behavior while IPv6 doesn't?
IPv4 does fragmentation on the path while IPv6 does always respond with
packet-too-big errors. The interface MTU will always be greater than
the path MTU information. So we would discard packets we could actually
forward because of malicious information. After this change we would
let the hop, which really could not forward the packet, notify the host
of this problem.
IPv4 allowes fragmentation mid-path. In case someone does use a software
which tries to discover such paths and assumes that the kernel is handling
the discovered pmtu information automatically. This should be an extremly
rare case, but because I could not exclude the possibility this knob is
provided. Also this software could insert non-locked mtu information
into the kernel. We cannot distinguish that from path mtu information
currently. Premature fragmentation could solve some problems in wrongly
configured networks, thus this switch is provided.
One frag-needed packet could reduce the path mtu down to 522 bytes
(route/min_pmtu).
Misc:
IPv6 neighbor discovery could advertise mtu information for an
interface. These information update the ipv6-specific interface mtu and
thus get used by the forwarding path.
Tunnel and xfrm output path will still honour path mtu and also respond
with Packet-too-Big or fragmentation-needed errors if needed.
Changelog for all patches:
v2)
* enabled ip_forward_use_pmtu by default
* reworded
v3)
* disabled ip_forward_use_pmtu by default
* reworded
v4)
* renamed ip_dst_mtu_secure to ip_dst_mtu_maybe_forward
* updated changelog accordingly
* removed unneeded !!(... & ...) double negations
v2)
* by default we honour pmtu information
3)
* only honor interface mtu
* rewritten and simplified
* no knob to fall back to old mode any more
v2)
* reworded Documentation
====================
Signed-off-by: David S. Miller <davem@davemloft.net>