Currently bridge can silently drop ipv4 fragments.
If node have loaded nf_defrag_ipv4 module but have no nf_conntrack_ipv4,
br_nf_pre_routing defragments incoming ipv4 fragments
but nfct check in br_nf_dev_queue_xmit does not allow re-fragment combined
packet back, and therefore it is dropped in br_dev_queue_push_xmit without
incrementing of any failcounters
It seems the only way to hit the ip_fragment code in the bridge xmit
path is to have a fragment list whose reassembled fragments go over
the mtu. This only happens if nf_defrag is enabled. Thanks to
Florian Westphal for providing feedback to clarify this.
Defragmentation ipv4 is required not only in conntracks but at least in
TPROXY target and socket match, therefore #ifdef is changed from
NF_CONNTRACK_IPV4 to NF_DEFRAG_IPV4
Signed-off-by: Vasily Averin <vvs@openvz.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Defrag user check in ip_expire was not updated after adding support for
"conntrack zones".
This bug manifests as a RFC violation, since the router will send
the icmp time exceeeded message when using conntrack zones.
Signed-off-by: Vasily Averin <vvs@openvz.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
else we may fail to forward skb even if original fragments do fit
outgoing link mtu:
1. remote sends 2k packets in two 1000 byte frags, DF set
2. we want to forward but only see '2k > mtu and DF set'
3. we then send icmp error saying that outgoing link is 1500
But original sender never sent a packet that would not fit
the outgoing link.
Setting local_df makes outgoing path test size vs.
IPCB(skb)->frag_max_size, so we will still send the correct
error in case the largest original size did not fit
outgoing link mtu.
Reported-by: Maxime Bizon <mbizon@freebox.fr>
Suggested-by: Maxime Bizon <mbizon@freebox.fr>
Fixes: 5f2d04f1f9 (ipv4: fix path MTU discovery with connection tracking)
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
commit 0eba801b64 tried to fix a race
where nat initialisation can happen after ctnetlink-created conntrack
has been created.
However, it causes the nat module(s) to be loaded needlessly on
systems that are not using NAT.
Fortunately, we do not have to create null bindings in that case.
conntracks injected via ctnetlink always have the CONFIRMED bit set,
which prevents addition of the nat extension in nf_nat_ipv4/6_fn().
We only need to make sure that either no nat extension is added
or that we've created both src and dst manips.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix format string mismatch in bonding_show_min_links().
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To properly match iif in ip rules we have to provide
LOOPBACK_IFINDEX in flowi6_iif, not 0. Some ip6mr_fib_lookup
and fib6_rule_lookup callers need such fix.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't transition to the PF state on every strike after 'Path.Max.Retrans'.
Per draft-ietf-tsvwg-sctp-failover-03 Section 5.1.6:
Additional (PMR - PFMR) consecutive timeouts on a PF destination
confirm the path failure, upon which the destination transitions to the
Inactive state. As described in [RFC4960], the sender (i) SHOULD notify
ULP about this state transition, and (ii) transmit heartbeats to the
Inactive destination at a lower frequency as described in Section 8.3 of
[RFC4960].
This also prevents sending SCTP_ADDR_UNREACHABLE to the user as the state
bounces between SCTP_INACTIVE and SCTP_PF for each subsequent strike.
Signed-off-by: Karl Heiss <kheiss@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With commit cc9fa74e2a ("slip/slcan: added locking in wakeup function") a
formerly missing locking was added to slip.c and slcan.c by Andre Naujoks.
Alexander Stein contributed the fix 367525c8c2 ("can: slcan: Fix spinlock
variant") as the kernel lock debugging advised to use spin_lock_bh() instead
of just using spin_lock().
This fix has to be applied to the same code section in slip.c for the same
reason too.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bjørn Mork says:
====================
qmi_wwan: adding a few new devices
Adding some new and some old QMI devices. A similar series for
usb-serial support will be posted as well.
These new device ID patches should also go to all maintained stable kernels
where they apply. I believe that should be stable-3.10 and newer.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Dan writes:
"The Dell drivers use the same configuration for PIDs:
81A2: Dell Wireless 5806 Gobi(TM) 4G LTE Mobile Broadband Card
81A3: Dell Wireless 5570 HSPA+ (42Mbps) Mobile Broadband Card
81A4: Dell Wireless 5570e HSPA+ (42Mbps) Mobile Broadband Card
81A8: Dell Wireless 5808 Gobi(TM) 4G LTE Mobile Broadband Card
81A9: Dell Wireless 5808e Gobi(TM) 4G LTE Mobile Broadband Card
These devices are all clearly Sierra devices, but are also definitely
Gobi-based. The A8 might be the MC7700/7710 and A9 is likely a MC7750.
>From DellGobi5kSetup.exe from the Dell drivers:
usbif0: serial/firmware loader?
usbif2: nmea
usbif3: modem/ppp
usbif8: net/QMI"
Reported-by: AceLan Kao <acelan.kao@canonical.com>
Reported-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
A number of older CMOTech modems are based on Qualcomm
chips and exporting a QMI/wwan function.
Reported-by: Lars Melin <larsm17@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 813b3b5db8 (ipv4: Use caller's on-stack flowi as-is
in output route lookups.) introduces another regression which
is very similar to the problem of commit e6b45241c (ipv4: reset
flowi parameters on route connect) wants to fix:
Before we call ip_route_output_key() in sctp_v4_get_dst() to
get a dst that matches a bind address as the source address,
we have already called this function previously and the flowi
parameters have been initialized including flowi4_oif, so when
we call this function again, the process in __ip_route_output_key()
will be different because of the setting of flowi4_oif, and we'll
get a networking device which corresponds to the inputted flowi4_oif
as the output device, this is wrong because we'll never hit this
place if the previously returned source address of dst match one
of the bound addresses.
To reproduce this problem, a vlan setting is enough:
# ifconfig eth0 up
# route del default
# vconfig add eth0 2
# vconfig add eth0 3
# ifconfig eth0.2 10.0.1.14 netmask 255.255.255.0
# route add default gw 10.0.1.254 dev eth0.2
# ifconfig eth0.3 10.0.0.14 netmask 255.255.255.0
# ip rule add from 10.0.0.14 table 4
# ip route add table 4 default via 10.0.0.254 src 10.0.0.14 dev eth0.3
# sctp_darn -H 10.0.0.14 -P 36422 -h 10.1.4.134 -p 36422 -s -I
You'll detect that all the flow are routed to eth0.2(10.0.1.254).
Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds ability for the arc_emac to really handle its supplying clock.
To get the needed clock-frequency either a real clock or the previous
clock-frequency property must be provided.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The probe function at the moment only frees the netdev but does not disconnect
the phy or removes the mdio bus it registered.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
When bridge device is created with IFLA_ADDRESS, we are not calling
br_stp_change_bridge_id(), which leads to incorrect local fdb
management and bridge id calculation, and prevents us from receiving
frames on the bridge device.
Reported-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes the PTP Tx timestamp interrupt handler. The original
code misinterpreted the interrupt handler design. We were clearing the
ena_mask bit for the Timesync interrupts. This is done to indicate that
the interrupt will be handled in a scheduled work item (instead of
immediately) and that work item is responsible for re-enabling the
interrupts. However, the Tx timestamp was being handled immediately and
nothing was ever re-enabling it. This resulted in a single interrupt
working for the life of the driver.
This patch fixes the issue by instead clearing the bit from icr0 which
is used to indicate that the interrupt was immediately handled and can
be re-enabled right away. This patch also clears up a related issue due
to writing the PRTTSYN_STAT_0 register, which was unintentionally
clearing the cause bits for Timesync interrupts.
Change-ID: I057bd70d53c302f60fab78246989cbdfa469d83b
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'linux-can-fixes-for-3.15-20140424' of git://gitorious.org/linux-can/linux-can
Marc Kleine-Budde says:
====================
this is a pull request for net/master, for the v3.15 release cycle, consisting
of 26 patches.
Thomas Gleixner contributes 21 patches for the c_can driver, which address
several shortcomings in the driver like hardware initialisation, concurrency,
message ordering and poor performance. Two patches Oliver Hartkopp, one adds a
missing lock to the sja1000_isa driver, the other one fixes the return value in
the generic bit time configuration function. And finally a patch by Alexander
Stein, that fixes the slcan driver to use the correct spinlock variant.
To make it 26 patches, Wolfgang Grandegger patch for the c_can_pci
driver, which enables the bus master only for MSI and a patch by
Wolfram Sang, which converts the 'instance' in the c_can driver to the
proper type.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Vince Bridgers says:
====================
This series of patches addresses a handful of issues found in testing
and reported by users of the Altera Triple Speed Ethernet soft IP.
The patches address the following issues (in summary)
1) The SGDMA soft IP was found to incorrectly process receive packets
when the target physical address of the receive buffer was on
a boundary that's not 32-bit aligned. One of the patches addresses
this issue.
2) The pause quanta was not being set by the driver, one patch of this
series sets the pause quanta to the IEEE defined default value
since the hardware reset value is 0.
3) An issue in a error recovery path of the probe routine caused a
kernel panic in the event a phy was probed and could not be found.
A patch addresses this issue.
4) A change was made to the driver name for Ethtool support, and
comments added to support an addition to Ethtool to support
the Altera Triple Speed Ethernet controller.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes the name used by Ethtool to something more
conventional in preparation for TSE Ethtool register dump
support to be added in the near future.
Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch addresses a fault in the error recovery path of the probe
routine where the netdev structure was not being unregistered properly
leading to a panic only when the phy probe failed.
Abbreviated panic stack seen is as follows:
(free_netdev+0xXX) from (altera_tse_probe+0xXX)
(altera_tse_probe+0xXX) from (platform_drv_probe+0xXX)
(platform_drv_probe+0xXX) from (driver_probe_device+0xXX)
(driver_probe_device+0xXX) from (__driver_attach+0xXX)
(__driver_attach+0xXX) from (bus_for_each_dev+0xXX)
(bus_for_each_dev+0xXX) from (driver_attach+0xXX)
(driver_attach+0xXX) from (bus_add_driver+0xXX)
(bus_add_driver+0xXX) from (driver_register+0xXX)
(driver_register+0xXX) from (__platform_driver_register+0xXX)
(__platform_driver_register+0xXX) from (altera_tse_driver_init+0xXX)
(altera_tse_driver_init+0xXX) from (do_one_initcall+0xXX)
(do_one_initcall+0xXX) from (kernel_init_freeable+0xXX)
(kernel_init_freeable+0xXX) from (kernel_init+0xXX)
(kernel_init+0xXX) from (ret_from_fork+0xXX)
Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch initializes the pause quanta set for transmitted pause frames
to the IEEE specified default of 0xffff.
Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch works around a recently discovered unaligned receive dma problem
with the Altera SGMDA. The Altera SGDMA component cannot be configured to
DMA data to unaligned addresses for receive packet operations from the
Triple Speed Ethernet component because of a potential data transfer
corruption that can occur. This patch addresses this issue by
utilizing the shift 16 bits feature of the Altera Triple Speed Ethernet
component and modifying the receive buffer physical addresses accordingly
such that the target receive DMA address is always aligned on a 32-bit
boundary.
Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Tested-by: Matthew Gerlach <mgerlach@altera.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yuval Mintz says:
====================
bnx2x: SRIOV bug fixes
This series contains 3 SRIOV bug fixes, 2 of which are regressions starting
with commit 2dc33bbc "bnx2x: Remove the sriov VFOP mechanism".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Starting with commit 2dc33bbc "bnx2x: Remove the sriov VFOP mechanism",
the bnx2x started enforcing vlan credits for all vlan configurations.
This exposed 2 issues:
- Vlan credits are not returned once a VF is removed; this causes a leak
of credits, and eventually will lead to VFs with no vlan credits.
- A vlan credit must be set aside for the Hypervisor to use, and should
not be visible to the VF.
Although linux VFs at the moment do not support vlan configuration [from the
VF side] which causes them to be resilient to this sort of issue, Windows VF
over linux hypervisors might fail to load as the vlan credits become depleted.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When removing a VF interface, the driver fails to release that VF's mailbox
and bulletin board allocated memory.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the ipv6 fib changes during a table dump, the walk is
restarted and the number of nodes dumped are skipped. But the existing
code doesn't advance to the next node after a node is skipped. This can
cause the dump to loop or produce lots of duplicates when the fib
is modified during the dump.
This change advances the walk to the next node if the current node is
skipped after a restart.
Signed-off-by: Kumar Sundararajan <kumar@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
slc_xmit is called within softirq context and locks sl->lock, but
slcan_write_wakeup is not softirq context, so we need to use
spin_[un]lock_bh!
Detected using kernel lock debugging mechanism.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
When trying to set a data bitrate on non CAN FD devices the 'ip' tool
answers with:
RTNETLINK answers: Unknown error 524
Rename '-ENOTSUPP' to '-EOPNOTSUPP' so that 'ip' answers correctly:
RTNETLINK answers: Operation not supported
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
When accessing the SJA1000 controller registers in the indirect access mode,
writing the register number and reading/writing the data has to be an atomic
attempt.
As the sja1000_isa driver is an old style driver with a fixed number of
instances the locking variable depends on the same index like all the other
configuration elements given on the module command line.
As a positive side effect dev->dev_id is populated by the instance index,
which was missing in 3e66d0138c ("can: populate netdev::dev_id for udev
discrimination").
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Coverity complains that c_can_pci_probe() calls pci_enable_msi() without
checking the result:
CID 712278 (#1 of 1): Unchecked return value (CHECKED_RETURN) 3. check_return:
Calling pci_enable_msi_block without checking return value (as is done
elsewhere 88 out of 105 times).
88 pci_enable_msi(pdev);
This is CID 712278.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Reported-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit 6439fbce10 (can: c_can: fix error checking of priv->instance in
probe()) found the warning but applied a suboptimal solution. Since, both
pdev->id and of_alias_get_id() return integers, it makes sense to convert the
variable to an integer and avoid the cast.
Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
It's suffcient to kill the TXIE bit in the message control register
even if the documentation of C and D CAN says that it's not allowed to
do that while MSGVAL is set. Reality tells a different story and this
change gives us another 2% of CPU back for not waiting on I/O.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Mark suggested to use one IF for the softirq and the other for the
xmit function to avoid the xmit lock.
That requires to write the frame into the interface first, then handle
the echo skb and store the dlc before committing the TX request to the
message ram.
We use an atomic to handle the active buffers instead of reading the
MSGVAL register as thats way faster especially on PCH/x86.
Suggested-by: Mark <mark5@del-llc.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Instead of obfuscating the code by artificial 16 bit splits use the
proper 32 bit assignments and split the result when writing to the
interface.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Remove the MASK from the TX transfer side.
Make the code readable and get rid of the annoying IFX_WRITE_XXX_16BIT
macros which are just obfuscating the code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Sigh!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Alexander reported that the new optimized handling of the RX fifo
causes random packet loss on Intel PCH C_CAN hardware.
After a few fruitless debugging sessions I got hold of a PCH (eg20t)
afflicted system. That machine does not have the CAN interface wired
up, but it was possible to reproduce the issue with the HW loopback
mode.
As Alexander observed correctly, clearing the NewDat flag along with
reading out the message buffer causes that issue on C_CAN, while D_CAN
handles that correctly.
Instead of restoring the original message buffer handling horror the
following workaround solves the issue:
transfer buffer to IF without clearing the NewDat
handle the message
clear NewDat bit
That's similar to the original code but conditional for C_CAN.
I really wonder why all user manuals (C_CAN, Intel PCH and some more)
recommend to clear the NewDat bit right away. The knows it all Oracle
operated by Gurgle does not unearth any useful information either. I
simply cannot believe that we are the first to uncover that HW issue.
Reported-and-tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The RX buffer split causes packet loss in the hardware:
What happens is:
RX Packet 1 --> message buffer 1 (newdat bit is not cleared)
RX Packet 2 --> message buffer 2 (newdat bit is not cleared)
RX Packet 3 --> message buffer 3 (newdat bit is not cleared)
RX Packet 4 --> message buffer 4 (newdat bit is not cleared)
RX Packet 5 --> message buffer 5 (newdat bit is not cleared)
RX Packet 6 --> message buffer 6 (newdat bit is not cleared)
RX Packet 7 --> message buffer 7 (newdat bit is not cleared)
RX Packet 8 --> message buffer 8 (newdat bit is not cleared)
Clear newdat bit in message buffer 1
Clear newdat bit in message buffer 2
Clear newdat bit in message buffer 3
Clear newdat bit in message buffer 4
Clear newdat bit in message buffer 5
Clear newdat bit in message buffer 6
Clear newdat bit in message buffer 7
Clear newdat bit in message buffer 8
Now if during that clearing of newdat bits, a new message comes in,
the HW gets confused and drops it.
It does not matter how many of them you clear. I put a delay between
clear of buffer 1 and buffer 2 which was long enough that the message
should have been queued either in buffer 1 or buffer 9. But it did not
show up anywhere. The next message ended up in buffer 1. So the
hardware lost a packet of course without telling it via one of the
error handlers.
That does not happen on all clear newdat bit events. I see one of 10k
packets dropped in the scenario which allows us to reproduce. But the
trace looks always the same.
Not splitting the RX Buffer avoids the packet loss but can cause
reordering. It's hard to trigger, but it CAN happen.
With that mode we use the HW as it was probably designed for. We read
from the buffer 1 upwards and clear the buffer as we get the
message. That's how all microcontrollers use it. So I assume that the
way we handle the buffers was never really tested. According to the
public documentation it should just work :)
Let the user decide which evil is the lesser one.
[ Oliver Hartkopp: Provided a sane config option and help text and
made me switch to favour potential and unlikely reordering over
packet loss ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>