linux.git/drivers/net/netdevsim/ethtool.c, branch v6.18.21

ethtool: add FEC bins histogram report

2025-09-26T23:49:18+00:00

IEEE 802.3ck-2022 defines counters for FEC bins and 802.3df-2024
clarifies it a bit further. Implement reporting interface through as
addition to FEC stats available in ethtool. Drivers can leave bin
counter uninitialized if per-lane values are provided. In this case the
core will recalculate summ for the bin.

Signed-off-by: Vadim Fedorenko 
Reviewed-by: Aleksandr Loktionov 
Link: https://patch.msgid.link/20250924124037.1508846-2-vadim.fedorenko@linux.dev
Signed-off-by: Jakub Kicinski

netdevsim: implement peer queue flow control

2025-07-15T00:36:50+00:00

Add flow control mechanism between paired netdevsim devices to stop the
TX queue during high traffic scenarios. When a receive queue becomes
congested (approaching NSIM_RING_SIZE limit), the corresponding transmit
queue on the peer device is stopped using netif_subqueue_try_stop().

Once the receive queue has sufficient capacity again, the peer's
transmit queue is resumed with netif_tx_wake_queue().

Key changes:
  * Add nsim_stop_peer_tx_queue() to pause peer TX when RX queue is full
  * Add nsim_start_peer_tx_queue() to resume peer TX when RX queue drains
  * Implement queue mapping validation to ensure TX/RX queue count match
  * Wake all queues during device unlinking to prevent stuck queues
  * Use RCU protection when accessing peer device references
  * wake the queues when changing the queue numbers
  * Remove IFF_NO_QUEUE given it will enqueue packets now

The flow control only activates when devices have matching TX/RX queue
counts to ensure proper queue mapping.

Suggested-by: Jakub Kicinski 
Signed-off-by: Breno Leitao 
Link: https://patch.msgid.link/20250711-netdev_flow_control-v3-1-aa1d5a155762@debian.org
Signed-off-by: Jakub Kicinski

net: ethtool: try to protect all callback with netdev instance lock

2025-03-06T20:59:44+00:00

Protect all ethtool callbacks and PHY related state with the netdev
instance lock, for drivers which want / need to have their ops
instance-locked. Basically take the lock everywhere we take rtnl_lock.
It was tempting to take the lock in ethnl_ops_begin(), but turns
out we actually nest those calls (when generating notifications).

Tested-by: Maxime Chevallier 
Cc: Saeed Mahameed 
Signed-off-by: Stanislav Fomichev 
Link: https://patch.msgid.link/20250305163732.2766420-11-sdf@fomichev.me
Signed-off-by: Jakub Kicinski

selftests: drv-net: test XDP, HDS auto and the ioctl path

2025-02-24T22:16:37+00:00

Test XDP and HDS interaction. While at it add a test for using the IOCTL,
as that turned out to be the real culprit.

Testing bnxt:

  # NETIF=eth0 ./ksft-net-drv/drivers/net/hds.py
  KTAP version 1
  1..12
  ok 1 hds.get_hds
  ok 2 hds.get_hds_thresh
  ok 3 hds.set_hds_disable # SKIP disabling of HDS not supported by the device
  ok 4 hds.set_hds_enable
  ok 5 hds.set_hds_thresh_zero
  ok 6 hds.set_hds_thresh_max
  ok 7 hds.set_hds_thresh_gt
  ok 8 hds.set_xdp
  ok 9 hds.enabled_set_xdp
  ok 10 hds.ioctl
  ok 11 hds.ioctl_set_xdp
  ok 12 hds.ioctl_enabled_set_xdp
  # Totals: pass:11 fail:0 xfail:0 xpass:0 skip:1 error:0

and netdevsim:

  # ./ksft-net-drv/drivers/net/hds.py
  KTAP version 1
  1..12
  ok 1 hds.get_hds
  ok 2 hds.get_hds_thresh
  ok 3 hds.set_hds_disable
  ok 4 hds.set_hds_enable
  ok 5 hds.set_hds_thresh_zero
  ok 6 hds.set_hds_thresh_max
  ok 7 hds.set_hds_thresh_gt
  ok 8 hds.set_xdp
  ok 9 hds.enabled_set_xdp
  ok 10 hds.ioctl
  ok 11 hds.ioctl_set_xdp
  ok 12 hds.ioctl_enabled_set_xdp
  # Totals: pass:12 fail:0 xfail:0 xpass:0 skip:0 error:0

Netdevsim needs a sane default for tx/rx ring size.

ethtool 6.11 is needed for the --disable-netlink option.

Acked-by: Stanislav Fomichev 
Tested-by: Taehee Yoo 
Link: https://patch.msgid.link/20250221025141.1132944-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdevsim: don't assume core pre-populates HDS params on GET

2025-01-27T22:37:11+00:00

Syzbot reports:

  BUG: KMSAN: uninit-value in nsim_get_ringparam+0xa8/0xe0 drivers/net/netdevsim/ethtool.c:77
   nsim_get_ringparam+0xa8/0xe0 drivers/net/netdevsim/ethtool.c:77
   ethtool_set_ringparam+0x268/0x570 net/ethtool/ioctl.c:2072
   __dev_ethtool net/ethtool/ioctl.c:3209 [inline]
   dev_ethtool+0x126d/0x2a40 net/ethtool/ioctl.c:3398
   dev_ioctl+0xb0e/0x1280 net/core/dev_ioctl.c:759

This is the SET path, where we call GET to either check user request
against max values, or check if any of the settings will change.

The logic in netdevsim is trying to report the default (ENABLED)
if user has not requested any specific setting. The user setting
is recorded in dev->cfg, don't depend on kernel_ringparam being
pre-populated with it.

Fixes: 928459bbda19 ("net: ethtool: populate the default HDS params in the core")
Reported-by: Eric Dumazet 
Reported-by: syzbot+b3bcd80232d00091e061@syzkaller.appspotmail.com
Tested-by: syzbot+b3bcd80232d00091e061@syzkaller.appspotmail.com
Link: https://patch.msgid.link/20250123221410.1067678-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: ethtool: populate the default HDS params in the core

2025-01-20T19:44:58+00:00

The core has the current HDS config, it can pre-populate the values
for the drivers. While at it, remove the zero-setting in netdevsim.
Zero are the default values since the config is zalloc'ed.

Reviewed-by: Michael Chan 
Link: https://patch.msgid.link/20250119020518.1962249-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: move HDS config from ethtool state

2025-01-20T19:44:57+00:00

Separate the HDS config from the ethtool state struct.
The HDS config contains just simple parameters, not state.
Having it as a separate struct will make it easier to clone / copy
and also long term potentially make it per-queue.

Reviewed-by: Michael Chan 
Link: https://patch.msgid.link/20250119020518.1962249-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: add netdev_lock() / netdev_unlock() helpers

2025-01-16T03:13:33+00:00

Add helpers for locking the netdev instance, use it in drivers
and the shaper code. This will make grepping for the lock usage
much easier, as we extend the lock to cover more fields.

Reviewed-by: Joe Damato 
Reviewed-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Reviewed-by: Przemek Kitszel 
Link: https://patch.msgid.link/20250115035319.559603-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdevsim: add HDS feature

2025-01-15T22:42:12+00:00

HDS options(tcp-data-split, hds-thresh) have dependencies between other
features like XDP. Basic dependencies are checked in the core API.
netdevsim is very useful to check basic dependencies.

The default tcp-data-split mode is UNKNOWN but netdevsim driver
returns ENABLED when ethtool dumps tcp-data-split mode.
The default value of HDS threshold is 0 and the maximum value is 1024.

ethtool shows like this.

ethtool -g eni1np1
Ring parameters for eni1np1:
Pre-set maximums:
...
HDS thresh:             1024
Current hardware settings:
...
TCP data split:         on
HDS thresh:             0

ethtool -G eni1np1 tcp-data-split on hds-thresh 1024
ethtool -g eni1np1
Ring parameters for eni1np1:
Pre-set maximums:
...
HDS thresh:             1024
Current hardware settings:
...
TCP data split:         on
HDS thresh:             1024

Signed-off-by: Taehee Yoo 
Link: https://patch.msgid.link/20250114142852.3364986-10-ap420073@gmail.com
Signed-off-by: Jakub Kicinski

testing: net-drv: add basic shaper test

2024-10-10T15:30:23+00:00

Leverage a basic/dummy netdevsim implementation to do functional
coverage for NL interface.

Reviewed-by: Jiri Pirko 
Signed-off-by: Paolo Abeni 
Link: https://patch.msgid.link/43092afbf38365c796088bf8fc155e523ab434ae.1728460186.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski