Commits · be6ff9665d642d4cd0800b508ded289eaa5b02a2 · Kirill Smelkov / linux

20 Apr, 2022 6 commits

net: dsa: don't emit targeted cross-chip notifiers for MTU change · be6ff966

Vladimir Oltean authored Apr 15, 2022

A cross-chip notifier with "targeted_match=true" is one that matches
only the local port of the switch that emitted it. In other words,
passing through the cross-chip notifier layer serves no purpose.

Eliminate this concept by calling directly ds->ops->port_change_mtu
instead of emitting a targeted cross-chip notifier. This leaves the
DSA_NOTIFIER_MTU event being emitted only for MTU updates on the CPU
port, which need to be reflected also across all DSA links.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

be6ff966

net: dsa: drop dsa_slave_priv from dsa_slave_change_mtu · 4715029f

Vladimir Oltean authored Apr 15, 2022

We can get a hold of the "ds" pointer directly from "dp", no need for
the dsa_slave_priv.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4715029f

net: dsa: avoid one dsa_to_port() in dsa_slave_change_mtu · cf1c39d3

Vladimir Oltean authored Apr 15, 2022

We could retrieve the cpu_dp pointer directly from the "dp" we already
have, no need to resort to dsa_to_port(ds, port).

This change also removes the need for an "int port", so that is also
deleted.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

cf1c39d3

net: dsa: use dsa_tree_for_each_user_port in dsa_slave_change_mtu · b2033a05

Vladimir Oltean authored Apr 15, 2022

Use the more conventional iterator over user ports instead of explicitly
ignoring them, and use the more conventional name "other_dp" instead of
"dp_iter", for readability.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

b2033a05

net: dsa: make cross-chip notifiers more efficient for host events · 726816a1

Vladimir Oltean authored Apr 15, 2022

To determine whether a given port should react to the port targeted by
the notifier, dsa_port_host_vlan_match() and dsa_port_host_address_match()
look at the positioning of the switch port currently executing the
notifier relative to the switch port for which the notifier was emitted.

To maintain stylistic compatibility with the other match functions from
switch.c, the host address and host VLAN match functions take the
notifier information about targeted port, switch and tree indices as
argument. However, these functions only use that information to retrieve
the struct dsa_port *targeted_dp, which is an invariant for the outer
loop that calls them. So it makes more sense to calculate the targeted
dp only once, and pass it to them as argument.

But furthermore, the targeted dp is actually known at the time the call
to dsa_port_notify() is made. It is just that we decide to only save the
indices of the port, switch and tree in the notifier structure, just to
retrace our steps and find the dp again using dsa_switch_find() and
dsa_to_port().

But both the above functions are relatively expensive, since they need
to iterate through lists. It appears more straightforward to make all
notifiers just pass the targeted dp inside their info structure, and
have the code that needs the indices to look at info->dp->index instead
of info->port, or info->dp->ds->index instead of info->sw_index, or
info->dp->ds->dst->index instead of info->tree_index.

For the sake of consistency, all cross-chip notifiers are converted to
pass the "dp" directly.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

726816a1

net: dsa: move reset of VLAN filtering to dsa_port_switchdev_unsync_attrs · 8e9e678e

Vladimir Oltean authored Apr 15, 2022

In dsa_port_switchdev_unsync_attrs() there is a comment that resetting
the VLAN filtering isn't done where it is expected. And since commit
108dc874 ("net: dsa: Avoid cross-chip syncing of VLAN filtering"),
there is no reason to handle this in switch.c either.

Therefore, move the logic to port.c, and adapt it slightly to the data
structures and naming conventions from there.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

8e9e678e

19 Apr, 2022 8 commits

Merge branch 'rtnetlink-improve-alt_ifname-config-and-fix-dangerous-group-usage' · cc4bdef2

Paolo Abeni authored Apr 19, 2022

Florent Fourcot says:

====================
rtnetlink: improve ALT_IFNAME config and fix dangerous GROUP usage

First commit forbids dangerous calls when both IFNAME and GROUP are
given, since it can introduce unexpected behaviour when IFNAME does not
match any interface.

Second patch achieves primary goal of this patchset to fix/improve
IFLA_ALT_IFNAME attribute, since previous code was never working for
newlink/setlink. ip-link command is probably getting interface index
before, and was not using this feature.

Last two patches are improving error code on corner cases.

Changes in v2:
  * Remove ifname argument in rtnl_dev_get/do_setlink
    functions (simplify code)
  * Use a boolean to avoid condition duplication in __rtnl_newlink

Changes in v3:
  * Simplify rtnl_dev_get signature

Changes in v4:
  * Rename link_lookup to link_specified

Changes in v5:
  * Re-order patches
====================

Link: https://lore.kernel.org/r/20220415165330.10497-1-florent.fourcot@wifirst.frSigned-off-by: Paolo Abeni <pabeni@redhat.com>

cc4bdef2

rtnetlink: return EINVAL when request cannot succeed · b6177d32

Florent Fourcot authored Apr 15, 2022

A request without interface name/interface index/interface group cannot
work. We should return EINVAL
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Brian Baboch <brian.baboch@wifirst.fr>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

b6177d32

rtnetlink: return ENODEV when IFLA_ALT_IFNAME is used in dellink · dee04163

Florent Fourcot authored Apr 15, 2022

If IFLA_ALT_IFNAME is set and given interface is not found,
we should return ENODEV and be consistent with IFLA_IFNAME
behaviour
This commit extends feature of commit 76c9ac0e,
"net: rtnetlink: add possibility to use alternative names as message handle"

CC: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Brian Baboch <brian.baboch@wifirst.fr>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

dee04163

rtnetlink: enable alt_ifname for setlink/newlink · 5ea08b52

Florent Fourcot authored Apr 15, 2022

buffer called "ifname" given in function rtnl_dev_get
is always valid when called by setlink/newlink,
but contains only empty string when IFLA_IFNAME is not given. So
IFLA_ALT_IFNAME is always ignored

This patch fixes rtnl_dev_get function with a remove of ifname argument,
and move ifname copy in do_setlink when required.

It extends feature of commit 76c9ac0e,
"net: rtnetlink: add possibility to use alternative names as message
handle""

CC: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Brian Baboch <brian.baboch@wifirst.fr>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

5ea08b52

rtnetlink: return ENODEV when ifname does not exist and group is given · ef2a7c90

Florent Fourcot authored Apr 15, 2022

When the interface does not exist, and a group is given, the given
parameters are being set to all interfaces of the given group. The given
IFNAME/ALT_IF_NAME are being ignored in that case.

That can be dangerous since a typo (or a deleted interface) can produce
weird side effects for caller:

Case 1:

 IFLA_IFNAME=valid_interface
 IFLA_GROUP=1
 MTU=1234

Case 1 will update MTU and group of the given interface "valid_interface".

Case 2:

 IFLA_IFNAME=doesnotexist
 IFLA_GROUP=1
 MTU=1234

Case 2 will update MTU of all interfaces in group 1. IFLA_IFNAME is
ignored in this case

This behaviour is not consistent and dangerous. In order to fix this issue,
we now return ENODEV when the given IFNAME does not exist.
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Brian Baboch <brian.baboch@wifirst.fr>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

ef2a7c90

Merge branch 'net-sched-allow-user-to-select-txqueue' · 8b11c35d

Paolo Abeni authored Apr 19, 2022

Tonghao Zhang says:

====================
net: sched: allow user to select txqueue

From: Tonghao Zhang <xiangxia.m.yue@gmail.com>

Patch 1 allow user to select txqueue in clsact hook.
Patch 2 support skbhash to select txqueue.
====================

Link: https://lore.kernel.org/r/20220415164046.26636-1-xiangxia.m.yue@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

8b11c35d

net: sched: support hash selecting tx queue · 38a6f086

Tonghao Zhang authored Apr 16, 2022

This patch allows users to pick queue_mapping, range
from A to B. Then we can load balance packets from A
to B tx queue. The range is an unsigned 16bit value
in decimal format.

$ tc filter ... action skbedit queue_mapping skbhash A B

"skbedit queue_mapping QUEUE_MAPPING" (from "man 8 tc-skbedit")
is enhanced with flags: SKBEDIT_F_TXQ_SKBHASH

  +----+      +----+      +----+
  | P1 |      | P2 |      | Pn |
  +----+      +----+      +----+
    |           |           |
    +-----------+-----------+
                |
                | clsact/skbedit
                |      MQ
                v
    +-----------+-----------+
    | q0        | qn        | qm
    v           v           v
  HTB/FQ       FIFO   ...  FIFO

For example:
If P1 sends out packets to different Pods on other host, and
we want distribute flows from qn - qm. Then we can use skb->hash
as hash.

setup commands:
$ NETDEV=eth0
$ ip netns add n1
$ ip link add ipv1 link $NETDEV type ipvlan mode l2
$ ip link set ipv1 netns n1
$ ip netns exec n1 ifconfig ipv1 2.2.2.100/24 up

$ tc qdisc add dev $NETDEV clsact
$ tc filter add dev $NETDEV egress protocol ip prio 1 \
        flower skip_hw src_ip 2.2.2.100 action skbedit queue_mapping skbhash 2 6
$ tc qdisc add dev $NETDEV handle 1: root mq
$ tc qdisc add dev $NETDEV parent 1:1 handle 2: htb
$ tc class add dev $NETDEV parent 2: classid 2:1 htb rate 100kbit
$ tc class add dev $NETDEV parent 2: classid 2:2 htb rate 200kbit
$ tc qdisc add dev $NETDEV parent 1:2 tbf rate 100mbit burst 100mb latency 1
$ tc qdisc add dev $NETDEV parent 1:3 pfifo
$ tc qdisc add dev $NETDEV parent 1:4 pfifo
$ tc qdisc add dev $NETDEV parent 1:5 pfifo
$ tc qdisc add dev $NETDEV parent 1:6 pfifo
$ tc qdisc add dev $NETDEV parent 1:7 pfifo

$ ip netns exec n1 iperf3 -c 2.2.2.1 -i 1 -t 10 -P 10

pick txqueue from 2 - 6:
$ ethtool -S $NETDEV | grep -i tx_queue_[0-9]_bytes
     tx_queue_0_bytes: 42
     tx_queue_1_bytes: 0
     tx_queue_2_bytes: 11442586444
     tx_queue_3_bytes: 7383615334
     tx_queue_4_bytes: 3981365579
     tx_queue_5_bytes: 3983235051
     tx_queue_6_bytes: 6706236461
     tx_queue_7_bytes: 42
     tx_queue_8_bytes: 0
     tx_queue_9_bytes: 0

txqueues 2 - 6 are mapped to classid 1:3 - 1:7
$ tc -s class show dev $NETDEV
...
class mq 1:3 root leaf 8002:
 Sent 11949133672 bytes 7929798 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 0b 0p requeues 0
class mq 1:4 root leaf 8003:
 Sent 7710449050 bytes 5117279 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 0b 0p requeues 0
class mq 1:5 root leaf 8004:
 Sent 4157648675 bytes 2758990 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 0b 0p requeues 0
class mq 1:6 root leaf 8005:
 Sent 4159632195 bytes 2759990 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 0b 0p requeues 0
class mq 1:7 root leaf 8006:
 Sent 7003169603 bytes 4646912 pkt (dropped 0, overlimits 0 requeues 0)
 backlog 0b 0p requeues 0
...

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Talal Ahmad <talalahmad@google.com>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Antoine Tenart <atenart@kernel.org>
Cc: Wei Wang <weiwan@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

38a6f086

net: sched: use queue_mapping to pick tx queue · 2f1e85b1

Tonghao Zhang authored Apr 16, 2022

This patch fixes issue:
* If we install tc filters with act_skbedit in clsact hook.
  It doesn't work, because netdev_core_pick_tx() overwrites
  queue_mapping.

  $ tc filter ... action skbedit queue_mapping 1

And this patch is useful:
* We can use FQ + EDT to implement efficient policies. Tx queues
  are picked by xps, ndo_select_queue of netdev driver, or skb hash
  in netdev_core_pick_tx(). In fact, the netdev driver, and skb
  hash are _not_ under control. xps uses the CPUs map to select Tx
  queues, but we can't figure out which task_struct of pod/containter
  running on this cpu in most case. We can use clsact filters to classify
  one pod/container traffic to one Tx queue. Why ?

  In containter networking environment, there are two kinds of pod/
  containter/net-namespace. One kind (e.g. P1, P2), the high throughput
  is key in these applications. But avoid running out of network resource,
  the outbound traffic of these pods is limited, using or sharing one
  dedicated Tx queues assigned HTB/TBF/FQ Qdisc. Other kind of pods
  (e.g. Pn), the low latency of data access is key. And the traffic is not
  limited. Pods use or share other dedicated Tx queues assigned FIFO Qdisc.
  This choice provides two benefits. First, contention on the HTB/FQ Qdisc
  lock is significantly reduced since fewer CPUs contend for the same queue.
  More importantly, Qdisc contention can be eliminated completely if each
  CPU has its own FIFO Qdisc for the second kind of pods.

  There must be a mechanism in place to support classifying traffic based on
  pods/container to different Tx queues. Note that clsact is outside of Qdisc
  while Qdisc can run a classifier to select a sub-queue under the lock.

  In general recording the decision in the skb seems a little heavy handed.
  This patch introduces a per-CPU variable, suggested by Eric.

  The xmit.skip_txqueue flag is firstly cleared in __dev_queue_xmit().
  - Tx Qdisc may install that skbedit actions, then xmit.skip_txqueue flag
    is set in qdisc->enqueue() though tx queue has been selected in
    netdev_tx_queue_mapping() or netdev_core_pick_tx(). That flag is cleared
    firstly in __dev_queue_xmit(), is useful:
  - Avoid picking Tx queue with netdev_tx_queue_mapping() in next netdev
    in such case: eth0 macvlan - eth0.3 vlan - eth0 ixgbe-phy:
    For example, eth0, macvlan in pod, which root Qdisc install skbedit
    queue_mapping, send packets to eth0.3, vlan in host. In __dev_queue_xmit() of
    eth0.3, clear the flag, does not select tx queue according to skb->queue_mapping
    because there is no filters in clsact or tx Qdisc of this netdev.
    Same action taked in eth0, ixgbe in Host.
  - Avoid picking Tx queue for next packet. If we set xmit.skip_txqueue
    in tx Qdisc (qdisc->enqueue()), the proper way to clear it is clearing it
    in __dev_queue_xmit when processing next packets.

  For performance reasons, use the static key. If user does not config the NET_EGRESS,
  the patch will not be compiled.

  +----+      +----+      +----+
  | P1 |      | P2 |      | Pn |
  +----+      +----+      +----+
    |           |           |
    +-----------+-----------+
                |
                | clsact/skbedit
                |      MQ
                v
    +-----------+-----------+
    | q0        | q1        | qn
    v           v           v
  HTB/FQ      HTB/FQ  ...  FIFO

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Talal Ahmad <talalahmad@google.com>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Cc: Antoine Tenart <atenart@kernel.org>
Cc: Wei Wang <weiwan@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

2f1e85b1

18 Apr, 2022 20 commits

docs: net: dsa: describe issues with checksum offload · a997157e

Luiz Angelo Daros de Luca authored Apr 16, 2022

DSA tags before IP header (categories 1 and 2) or after the payload (3)
might introduce offload checksum issues.
Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

a997157e

Merge branch 'mlxsw-line-card' · 2a38de06

David S. Miller authored Apr 18, 2022

Ido Schimmel says:

====================
mlxsw: Introduce line card support for modular switch

Jiri says:

This patchset introduces support for modular switch systems and also
introduces mlxsw support for NVIDIA Mellanox SN4800 modular switch.
It contains 8 slots to accommodate line cards - replaceable PHY modules
which may contain gearboxes.
Currently supported line card:
16X 100GbE (QSFP28)
Other line cards that are going to be supported:
8X 200GbE (QSFP56)
4X 400GbE (QSFP-DD)
There may be other types of line cards added in the future.

To be consistent with the port split configuration (splitter cabels),
the line card entities are treated in the similar way. The nature of
a line card is not "a pluggable device", but "a pluggable PHY module".

A concept of "provisioning" is introduced. The user may "provision"
certain slot with a line card type. Driver then creates all instances
(devlink ports, netdevices, etc) related to this line card type. It does
not matter if the line card is plugged-in at the time. User is able to
configure netdevices, devlink ports, setup port splitters, etc. From the
perspective of the switch ASIC, all is present and can be configured.

The carrier of netdevices stays down if the line card is not plugged-in.
Once the line card is inserted and activated, the carrier of
the related netdevices is then reflecting the physical line state,
same as for an ordinary fixed port.

Once user does not want to use the line card related instances
anymore, he can "unprovision" the slot. Driver then removes the
instances.

Patches 1-4 are extending devlink driver API and UAPI in order to
register, show, dump, provision and activate the line card.
Patches 5-17 are implementing the introduced API in mlxsw.
The last patch adds a selftest for mlxsw line cards.

Example:
$ devlink port # No ports are listed
$ devlink lc
pci/0000:01:00.0:
  lc 1 state unprovisioned
    supported_types:
       16x100G
  lc 2 state unprovisioned
    supported_types:
       16x100G
  lc 3 state unprovisioned
    supported_types:
       16x100G
  lc 4 state unprovisioned
    supported_types:
       16x100G
  lc 5 state unprovisioned
    supported_types:
       16x100G
  lc 6 state unprovisioned
    supported_types:
       16x100G
  lc 7 state unprovisioned
    supported_types:
       16x100G
  lc 8 state unprovisioned
    supported_types:
       16x100G

Note that driver exposes list supported line card types. Currently
there is only one: "16x100G".

To provision the slot #8:

$ devlink lc set pci/0000:01:00.0 lc 8 type 16x100G
$ devlink lc show pci/0000:01:00.0 lc 8
pci/0000:01:00.0:
  lc 8 state active type 16x100G
    supported_types:
       16x100G
$ devlink port
pci/0000:01:00.0/0: type notset flavour cpu port 0 splittable false
pci/0000:01:00.0/53: type eth netdev enp1s0nl8p1 flavour physical lc 8 port 1 splittable true lanes 4
pci/0000:01:00.0/54: type eth netdev enp1s0nl8p2 flavour physical lc 8 port 2 splittable true lanes 4
pci/0000:01:00.0/55: type eth netdev enp1s0nl8p3 flavour physical lc 8 port 3 splittable true lanes 4
pci/0000:01:00.0/56: type eth netdev enp1s0nl8p4 flavour physical lc 8 port 4 splittable true lanes 4
pci/0000:01:00.0/57: type eth netdev enp1s0nl8p5 flavour physical lc 8 port 5 splittable true lanes 4
pci/0000:01:00.0/58: type eth netdev enp1s0nl8p6 flavour physical lc 8 port 6 splittable true lanes 4
pci/0000:01:00.0/59: type eth netdev enp1s0nl8p7 flavour physical lc 8 port 7 splittable true lanes 4
pci/0000:01:00.0/60: type eth netdev enp1s0nl8p8 flavour physical lc 8 port 8 splittable true lanes 4
pci/0000:01:00.0/61: type eth netdev enp1s0nl8p9 flavour physical lc 8 port 9 splittable true lanes 4
pci/0000:01:00.0/62: type eth netdev enp1s0nl8p10 flavour physical lc 8 port 10 splittable true lanes 4
pci/0000:01:00.0/63: type eth netdev enp1s0nl8p11 flavour physical lc 8 port 11 splittable true lanes 4
pci/0000:01:00.0/64: type eth netdev enp1s0nl8p12 flavour physical lc 8 port 12 splittable true lanes 4
pci/0000:01:00.0/125: type eth netdev enp1s0nl8p13 flavour physical lc 8 port 13 splittable true lanes 4
pci/0000:01:00.0/126: type eth netdev enp1s0nl8p14 flavour physical lc 8 port 14 splittable true lanes 4
pci/0000:01:00.0/127: type eth netdev enp1s0nl8p15 flavour physical lc 8 port 15 splittable true lanes 4
pci/0000:01:00.0/128: type eth netdev enp1s0nl8p16 flavour physical lc 8 port 16 splittable true lanes 4

To uprovision the slot #8:

$ devlink lc set pci/0000:01:00.0 lc 8 notype
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

2a38de06