There are several different places needing to make sure that a
connection gets disconnected or canceled. The exact action needed
depends on the connection state, so centralizing this logic can save
quite a lot of code duplication.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
bt_skb_alloc() returns NULL on error, it never returns an ERR_PTR.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For connection parameters that are left around until a disconnection
we should at least clear any auto-connection properties. This way a
new Add Device call is required to re-set them after calling Unpair
Device.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This header file only contains the platform data structure definition,
so move it to the include/linux/platform_data/ directory.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the inclusion of linux/mdio-gpio.h in nas4220b, wbd111 and wbd222
boards since mdio-gpio is not used.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix sun4i-emac not releasing the following resources:
-iomapped memory not released on probe-failure nor on remove
-clock not getting disabled on probe-failure nor on remove
-sram not being released on remove
And while at it also add error checking to the clk_prepare_enable call
done on probe.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/hisilicon/hns/hnae.c:442:1-3: WARNING: PTR_ERR_OR_ZERO can be used
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Generated by: scripts/coccinelle/api/ptr_ret.cocci
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert added SIT support to GRO with commit
19424e052f ("sit: Add gro callbacks to sit_offload"),
later reverted by Herbert Xu.
The problem came because Tom patch was building GRO
packets without proper meta data : If packets were locally
delivered, we would not care.
But if packets needed to be forwarded, GSO engine was not
able to segment individual segments.
With the following patch, we correctly set skb->encapsulation
and inner network header. We also update gso_type.
Tested:
Server :
netserver
modprobe dummy
ifconfig dummy0 8.0.0.1 netmask 255.255.255.0 up
arp -s 8.0.0.100 4e:32:51:04:47:e5
iptables -I INPUT -s 10.246.7.151 -j TEE --gateway 8.0.0.100
ifconfig sixtofour0
sixtofour0 Link encap:IPv6-in-IPv4
inet6 addr: 2002:af6:798::1/128 Scope:Global
inet6 addr: 2002:af6:798::/128 Scope:Global
UP RUNNING NOARP MTU:1480 Metric:1
RX packets:411169 errors:0 dropped:0 overruns:0 frame:0
TX packets:409414 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:20319631739 (20.3 GB) TX bytes:29529556 (29.5 MB)
Client :
netperf -H 2002:af6:798::1 -l 1000 &
Checked on server traffic copied on dummy0 and verify segments were
properly rebuilt, with proper IP headers, TCP checksums...
tcpdump on eth0 shows proper GRO aggregation takes place.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While testing my SIT/GRO patch using netfilter TEE module and a dummy
device, I found some features were missing :
TSO IPv6, UFO, and encapsulated traffic.
ethtool -k dummy0 now gives :
...
tcp-segmentation-offload: on
tx-tcp-segmentation: on
tx-tcp-ecn-segmentation: on
tx-tcp6-segmentation: on
udp-fragmentation-offload: on
...
tx-gre-segmentation: on
tx-ipip-segmentation: on
tx-sit-segmentation: on
tx-udp_tnl-segmentation: on
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If userspace provides a ct action with no nested mark or label, then the
storage for these fields is zeroed. Later when actions are requested,
such zeroed fields are serialized even though userspace didn't
originally specify them. Fix the behaviour by ensuring that no action is
serialized in this case, and reject actions where userspace attempts to
set these fields with mask=0. This should make netlink marshalling
consistent across deserialization/reserialization.
Reported-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
New, related connections are marked as such as part of ovs_ct_lookup(),
but they are not marked as "new" if the commit flag is used. Make this
consistent by setting the "new" flag whenever !nf_ct_is_confirmed(ct).
Reported-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The presence of this attribute does not modify the ct_state for the
current packet, only future packets. Make this more clear in the header
definition.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, 0-bits are generated in ct_state where the bit position is
undefined, and matches are accepted on these bit-positions. If userspace
requests to match the 0-value for this bit then it may expect only a
subset of traffic to match this value, whereas currently all packets
will have this bit set to 0. Fix this by rejecting such masks.
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains four Netfilter fixes for net, they are:
1) Fix Kconfig dependencies of new nf_dup_ipv4 and nf_dup_ipv6.
2) Remove bogus test nh_scope in IPv4 rpfilter match that is breaking
--accept-local, from Xin Long.
3) Wait for RCU grace period after dropping the pending packets in the
nfqueue, from Florian Westphal.
4) Fix sleeping allocation while holding spin_lock_bh, from Nikolay Borisov.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
if_nlmsg_size() overestimates the minimum allocation size of netlink
dump request (when called from rtnl_calcit()) or the size of the
message (when called from rtnl_getlink()). This is because
ext_filter_mask is not supported by rtnl_link_get_af_size() and
rtnl_link_get_size().
The over-estimation is significant when at least one netdev has many
VLANs configured (8 bytes for each configured VLAN).
This patch-set "rightsizes" the protocol specific attribute size
calculation by propagating ext_filter_mask to rtnl_link_get_af_size()
and adding this a argument to get_link_af_size op in rtnl_af_ops.
Bridge module already used filtering aware sizing for notifications.
br_get_link_af_size_filtered() is consistent with the modified
get_link_af_size op so it replaces br_get_link_af_size() in br_af_ops.
br_get_link_af_size() becomes unused and thus removed.
Signed-off-by: Ronen Arad <ronen.arad@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit d999297c3d ("tipc: reduce locking scope during packet reception")
we altered the packet retransmission function. Since then, when
restransmitting packets, we create a clone of the original buffer
using __pskb_copy(skb, MIN_H_SIZE), where MIN_H_SIZE is the size of
the area we want to have copied, but also the smallest possible TIPC
packet size. The value of MIN_H_SIZE is 24.
Unfortunately, __pskb_copy() also has the effect that the headroom
of the cloned buffer takes the size MIN_H_SIZE. This is too small
for carrying the packet over the UDP tunnel bearer, which requires
a minimum headroom of 28 bytes. A change to just use pskb_copy()
lets the clone inherit the original headroom of 80 bytes, but also
assumes that the copied data area is of at least that size, something
that is not always the case. So that is not a viable solution.
We now fix this by adding a check for sufficient headroom in the
transmit function of udp_media.c, and expanding it when necessary.
Fixes: commit d999297c3d ("tipc: reduce locking scope during packet reception")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CONFIG_NET_VENDOR_CAVIUM is only used to hide/show config options and to
include subdirectories in the build, so it doesn't make sense to make it
tristate.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code for message reassembly is erroneously assuming that
the the first arriving fragment buffer always is linear, and then goes
ahead resetting the fragment list of that buffer in anticipation of
more arriving fragments.
However, if the buffer already happens to be non-linear, we will
inadvertently drop the already attached fragment list, and later
on trig a BUG() in __pskb_pull_tail().
We see this happen when running fragmented TIPC multicast across UDP,
something made possible since
commit d0f91938be ("tipc: add ip/udp media type")
We fix this by not resetting the fragment list when the buffer is non-
linear, and by initiatlizing our private fragment list tail pointer to
the tail of the existing fragment list.
Fixes: commit d0f91938be ("tipc: add ip/udp media type")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
"openvswitch: Remove vport stats" removed the per-vport statistics, in
order to use the netdev's statistics fields.
"openvswitch: Fix ovs_vport_get_stats()" fixed the export of these stats
to user-space, by using the provided netdev_ops to collate them - but ovs
internal devices still use an unallocated dev->tstats field to count
packets, which are no longer exported by this api.
Allocate the dev->tstats field for ovs internal devices, and wire up
ndo_get_stats64 with the original implementation of
ovs_vport_get_stats().
On its own, "openvswitch: Fix ovs_vport_get_stats()" fixes the OOPs,
unmasking a full-on panic on arm64:
=============%<==============
[<ffffffbffc00ce4c>] internal_dev_recv+0xa8/0x170 [openvswitch]
[<ffffffbffc0008b4>] do_output.isra.31+0x60/0x19c [openvswitch]
[<ffffffbffc000bf8>] do_execute_actions+0x208/0x11c0 [openvswitch]
[<ffffffbffc001c78>] ovs_execute_actions+0xc8/0x238 [openvswitch]
[<ffffffbffc003dfc>] ovs_packet_cmd_execute+0x21c/0x288 [openvswitch]
[<ffffffc0005e8c5c>] genl_family_rcv_msg+0x1b0/0x310
[<ffffffc0005e8e60>] genl_rcv_msg+0xa4/0xe4
[<ffffffc0005e7ddc>] netlink_rcv_skb+0xb0/0xdc
[<ffffffc0005e8a94>] genl_rcv+0x38/0x50
[<ffffffc0005e76c0>] netlink_unicast+0x164/0x210
[<ffffffc0005e7b70>] netlink_sendmsg+0x304/0x368
[<ffffffc0005a21c0>] sock_sendmsg+0x30/0x4c
[SNIP]
Kernel panic - not syncing: Fatal exception in interrupt
=============%<==============
Fixes: 8c876639c9 ("openvswitch: Remove vport stats.")
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6e28b00082 ("net: Fix vti use case with oif in dst lookups for IPv6")
is missing the checks on FLOWI_FLAG_SKIP_NH_OIF. Add them.
Fixes: 42a7b32b73 ("xfrm: Add oif to dst lookups")
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The default fix broadcast window size is currently set to 20 packets.
This is a very low value, set at a time when we were still testing on
10 Mb/s hubs, and a change to it is long overdue.
Commit 7845989cb4 ("net: tipc: fix stall during bclink wakeup procedure")
revealed a problem with this low value. For messages of importance LOW,
the backlog queue limit will be calculated to 30 packets, while a
single, maximum sized message of 66000 bytes, carried across a 1500 MTU
network consists of 46 packets.
This leads to the following scenario (among others leading to the same
situation):
1: Msg 1 of 46 packets is sent. 20 packets go to the transmit queue, 26
packets to the backlog queue.
2: Msg 2 of 46 packets is attempted sent, but rejected because there is
no more space in the backlog queue at this level. The sender is added
to the wakeup queue with a "pending packets chain size" number of 46.
3: Some packets in the transmit queue are acked and released. We try to
wake up the sender, but the pending size of 46 is bigger than the LOW
wakeup limit of 30, so this doesn't happen.
5: Subsequent acks releases all the remaining buffers. Each time we test
for the wakeup criteria and find that 46 still is larger than 30,
even after both the transmit and the backlog queues are empty.
6: The sender is never woken up and given a chance to send its message.
He is stuck.
We could now loosen the wakeup criteria (used by link_prepare_wakeup())
to become equal to the send criteria (used by tipc_link_xmit()), i.e.,
by ignoring the "pending packets chain size" value altogether, or we can
just increase the queue limits so that the criteria can be satisfied
anyway. There are good reasons (potentially multiple waiting senders) to
not opt for the former solution, so we choose the latter one.
This commit fixes the problem by giving the broadcast link window a
default value of 50 packets. We also introduce a new minimum link
window size BCLINK_MIN_WIN of 32, which is enough to always avoid the
described situation. Finally, in order to not break any existing users
which may set the window explicitly, we enforce that the window is set
to the new minimum value in case the user is trying to set it to
anything lower.
Fixes: 7845989cb4 ("net: tipc: fix stall during bclink wakeup procedure")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's only one user of this helper which can be replaces with a call
to hci_pend_le_action_lookup() and a check for params->explicit_connect.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There's no need to clear the HCI_CONN_ENCRYPT_PEND flag in
smp_failure. In fact, this may cause the encryption tracking to get
out of sync as this has nothing to do with HCI activity.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The hci_le_create_connection_cancel() function needs to use the hdev
pointer in many places so add a variable for it to avoid the need to
dereference the hci_conn every time.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Instead of doing all of the LE-specific handling in an else-branch in
unpair_device() create a 'done' label for the BR/EDR branch to jump to
and then remove the else-branch completely.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use the new hci_conn_hash_lookup_le() API to look up LE connections.
This way we're guaranteed exact matches that also take into account
the address type.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use the new hci_conn_hash_lookup_le() API to look up LE connections.
This way we're guaranteed exact matches that also take into account
the address type.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Many of the existing LE connection lookups are forced to use
hci_conn_hash_lookup_ba() which doesn't take into account the address
type. What's worse, most of the users don't bother checking that the
returned address type matches what was wanted.
This patch adds a new helper API to look up LE connections based on
their address and address type, paving the way to have the
hci_conn_hash_lookup_ba() users converted to do more precise lookups.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The mgmt code needs to convert from mgmt/L2CAP address types to HCI in
many places. Having a dedicated helper function for this simplifies
code by shortening it and removing unnecessary 'addr_type' variables.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Configure ageing time to the HW for newly bridged device
CC: Scott Feldman <sfeldma@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Elad Raz <eladr@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is decrementing the pointer, instead of the value stored in the
pointer. KASan detects it as an out of bounds reference.
Reported-by: "Berry Cheng 程君(成淼)" <chengmiao.cj@alibaba-inc.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sometimes xennet_create_queues() may failed to created all requested
queues, we need to update num_queues to real created to avoid NULL
pointer dereference.
Signed-off-by: Joe Jin <joe.jin@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: David S. Miller <davem@davemloft.net>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
reset transport and unlock if misc_register failed.
Signed-off-by: Gao feng <omarapazanadi@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Philipp Kirchhofer says:
====================
net: mv643xx_eth: TSO TX data corruption fixes
as previously discussed [1] the mv643xx_eth driver has some
issues with data corruption when using TCP segmentation offload (TSO).
The following patch set improves this situation by fixing two data
corruption bugs in the TSO TX path.
Before applying the patches repeatedly accessing large files located on
a SMB share on my NSA325 NAS with TSO enabled resulted in different
hash sums, which confirmed that data corruption is happening during
file transfer. After applying the patches the hash sums were the same.
As this is my first patch submission please feel free to point out any
issues with the patch set.
[1] http://thread.gmane.org/gmane.linux.network/336530
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
To prevent a race between the TX DMA engine and the CPU the writing of the
first transmit descriptor must be deferred until all following descriptors
have been updated. The network card may otherwise start transmitting before
all packet descriptors are set up correctly, which leads to data corruption
or an aborted transmit operation.
This deferral is already done in the non-TSO TX path, implement it also in
the TSO TX path.
Signed-off-by: Philipp Kirchhofer <philipp@familie-kirchhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TX DMA engine requires that buffers with a size of 8 bytes or smaller
must be 64 bit aligned. This requirement may be violated when doing TSO,
as in this case larger skb frags can be broken up and transmitted in small
parts with then inappropriate alignment.
Fix this by checking for proper alignment before handing a buffer to the
DMA engine. If the data is misaligned realign it by copying it into the
TSO header data area.
Signed-off-by: Philipp Kirchhofer <philipp@familie-kirchhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yuchung Cheng says:
====================
RACK loss detection
RACK (Recent ACK) loss recovery uses the notion of time instead of
packet sequence (FACK) or counts (dupthresh).
It's inspired by the FACK heuristic in tcp_mark_lost_retrans(): when a
limited transmit (new data packet) is sacked in recovery, then any
retransmission sent before that newly sacked packet was sent must have
been lost, since at least one round trip time has elapsed.
But that existing heuristic from tcp_mark_lost_retrans()
has several limitations:
1) it can't detect tail drops since it depends on limited transmit
2) it's disabled upon reordering (assumes no reordering)
3) it's only enabled in fast recovery but not timeout recovery
RACK addresses these limitations with a core idea: an unacknowledged
packet P1 is deemed lost if a packet P2 that was sent later is is
s/acked, since at least one round trip has passed.
Since RACK cares about the time sequence instead of the data sequence
of packets, it can detect tail drops when a later retransmission is
s/acked, while FACK or dupthresh can't. For reordering RACK uses a
dynamically adjusted reordering window ("reo_wnd") to reduce false
positives on ever (small) degree of reordering, similar to the delayed
Early Retransmit.
In the current patch set RACK is only a supplemental loss detection
and does not trigger fast recovery. However we are developing RACK
to replace or consolidate FACK/dupthresh, early retransmit, and
thin-dupack. These heuristics all implicitly bear the time notion.
For example, the delayed Early Retransmit is simply applying RACK
to trigger the fast recovery with small inflight.
RACK requires measuring the minimum RTT. Tracking a global min is less
robust due to traffic engineering pathing changes. Therefore it uses a
windowed filter by Kathleen Nichols. The min RTT can also be useful
for various other purposes like congestion control or stat monitoring.
This patch has been used on Google servers for well over 1 year. RACK
has also been implemented in the QUIC protocol. We are submitting an
IETF draft as well.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the second half of RACK that uses the the most
recent transmit time among all delivered packets to detect losses.
tcp_rack_mark_lost() is called upon receiving a dubious ACK.
It then checks if an not-yet-sacked packet was sent at least
"reo_wnd" prior to the sent time of the most recently delivered.
If so the packet is deemed lost.
The "reo_wnd" reordering window starts with 1msec for fast loss
detection and changes to min-RTT/4 when reordering is observed.
We found 1msec accommodates well on tiny degree of reordering
(<3 pkts) on faster links. We use min-RTT instead of SRTT because
reordering is more of a path property but SRTT can be inflated by
self-inflicated congestion. The factor of 4 is borrowed from the
delayed early retransmit and seems to work reasonably well.
Since RACK is still experimental, it is now used as a supplemental
loss detection on top of existing algorithms. It is only effective
after the fast recovery starts or after the timeout occurs. The
fast recovery is still triggered by FACK and/or dupack threshold
instead of RACK.
We introduce a new sysctl net.ipv4.tcp_recovery for future
experiments of loss recoveries. For now RACK can be disabled by
setting it to 0.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is the first half of the RACK loss recovery.
RACK loss recovery uses the notion of time instead
of packet sequence (FACK) or counts (dupthresh). It's inspired by the
previous FACK heuristic in tcp_mark_lost_retrans(): when a limited
transmit (new data packet) is sacked, then current retransmitted
sequence below the newly sacked sequence must been lost,
since at least one round trip time has elapsed.
But it has several limitations:
1) can't detect tail drops since it depends on limited transmit
2) is disabled upon reordering (assumes no reordering)
3) only enabled in fast recovery ut not timeout recovery
RACK (Recently ACK) addresses these limitations with the notion
of time instead: a packet P1 is lost if a later packet P2 is s/acked,
as at least one round trip has passed.
Since RACK cares about the time sequence instead of the data sequence
of packets, it can detect tail drops when later retransmission is
s/acked while FACK or dupthresh can't. For reordering RACK uses a
dynamically adjusted reordering window ("reo_wnd") to reduce false
positives on ever (small) degree of reordering.
This patch implements tcp_advanced_rack() which tracks the
most recent transmission time among the packets that have been
delivered (ACKed or SACKed) in tp->rack.mstamp. This timestamp
is the key to determine which packet has been lost.
Consider an example that the sender sends six packets:
T1: P1 (lost)
T2: P2
T3: P3
T4: P4
T100: sack of P2. rack.mstamp = T2
T101: retransmit P1
T102: sack of P2,P3,P4. rack.mstamp = T4
T205: ACK of P4 since the hole is repaired. rack.mstamp = T101
We need to be careful about spurious retransmission because it may
falsely advance tp->rack.mstamp by an RTT or an RTO, causing RACK
to falsely mark all packets lost, just like a spurious timeout.
We identify spurious retransmission by the ACK's TS echo value.
If TS option is not applicable but the retransmission is acknowledged
less than min-RTT ago, it is likely to be spurious. We refrain from
using the transmission time of these spurious retransmissions.
The second half is implemented in the next patch that marks packet
lost using RACK timestamp.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a helper to prepare the first main RACK patch.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a helper to prepare the main RACK patch
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the existing lost retransmit detection because RACK subsumes
it completely. This also stops the overloading the ack_seq field of
the skb control block.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kathleen Nichols' algorithm for tracking the minimum RTT of a
data stream over some measurement window. It uses constant space
and constant time per update. Yet it almost always delivers
the same minimum as an implementation that has to keep all
the data in the window. The measurement window is tunable via
sysctl.net.ipv4.tcp_min_rtt_wlen with a default value of 5 minutes.
The algorithm keeps track of the best, 2nd best & 3rd best min
values, maintaining an invariant that the measurement time of
the n'th best >= n-1'th best. It also makes sure that the three
values are widely separated in the time window since that bounds
the worse case error when that data is monotonically increasing
over the window.
Upon getting a new min, we can forget everything earlier because
it has no value - the new min is less than everything else in the
window by definition and it's the most recent. So we restart fresh
on every new min and overwrites the 2nd & 3rd choices. The same
property holds for the 2nd & 3rd best.
Therefore we have to maintain two invariants to maximize the
information in the samples, one on values (1st.v <= 2nd.v <=
3rd.v) and the other on times (now-win <=1st.t <= 2nd.t <= 3rd.t <=
now). These invariants determine the structure of the code
The RTT input to the windowed filter is the minimum RTT measured
from ACK or SACK, or as the last resort from TCP timestamps.
The accessor tcp_min_rtt() returns the minimum RTT seen in the
window. ~0U indicates it is not available. The minimum is 1usec
even if the true RTT is below that.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently ca_seq_rtt_us does not use Kern's check. Fix that by
checking if any packet acked is a retransmit, for both RTT used
for RTT estimation and congestion control.
Fixes: 5b08e47ca ("tcp: prefer packet timing to TS-ECR for RTT")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Heiko Schocher says:
====================
net, phy, smsc: add posibility to disable energy detect mode
On some boards the energy enable detect mode leads in
trouble with some switches, so make the enabling of
this mode configurable through DT.
Therefore the property "smsc,disable-energy-detect" is
introduced.
Patch 1 introduces phy-handle support for the ti,cpsw
driver. This is needed now for the smsc phy.
Patch 2 adds the disable energy mode functionality
to the smsc phy
Changes in v2:
- add comments from Florian Fainelli
- I did not change disable property name into enable
because I fear to break existing behaviour
- add smsc vendor prefix
- remove CONFIG_OF and use __maybe_unused
- introduce "phy-handle" ability into ti,cpsw
driver, so I can remove bogus:
if (!of_node && dev->parent->of_node)
of_node = dev->parent->of_node;
construct. Therefore new patch for the ti,cpsw
driver is necessary.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
On some boards the energy enable detect mode leads in
trouble with some switches, so make the enabling of
this mode configurable through DT.
Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
add the ability to parse "phy-handle". This
is needed for phys, which have a DT node, and
need to parse DT properties.
Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
If a gigabit ethernet PHY is connected to a fast ethernet MAC,
then it can detect 1000 support from the partner but not use it.
This results in a forced speed of 1000 and RX/TX failure.
Check for 1000BASE-T support and then check the advertisement
configuration before setting the MAC speed to 1000mbit.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johan Hedberg