Commit Graph

1170862 Commits

Author SHA1 Message Date
Tony Nguyen
79d872c62b Documentation/eth/intel: Remove references to SourceForge
The out-of-tree driver is hosted on SourceForge, as this does not apply
to the kernel driver remove references to it. Also do some minor
formatting changes around this section.

Suggested-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
2023-03-30 09:35:04 -07:00
Tony Nguyen
8ba732befd Documentation/eth/intel: Update address for driver support
Update the email address for support to use Intel Wired LAN, the mailing
list used for kernel development.

Suggested-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
2023-03-30 09:34:59 -07:00
Wolfram Sang
da617cd8d9 smsc911x: remove superfluous variable init
phydev is assigned a value right away, no need to initialize it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230329064414.25028-1-wsa+renesas@sang-engineering.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 15:35:33 +02:00
Paolo Abeni
4ddd6375c3 Merge branch 'net-rps-rfs-improvements'
Eric Dumazet says:

====================
net: rps/rfs improvements

Jason Xing attempted to optimize napi_schedule_rps() by avoiding
unneeded NET_RX_SOFTIRQ raises: [1], [2]

This is quite complex to implement properly. I chose to implement
the idea, and added a similar optimization in ____napi_schedule()

Overall, in an intensive RPC workload, with 32 TX/RX queues with RFS
I was able to observe a ~10% reduction of NET_RX_SOFTIRQ
invocations.

While this had no impact on throughput or cpu costs on this synthetic
benchmark, we know that firing NET_RX_SOFTIRQ from softirq handler
can force __do_softirq() to wakeup ksoftirqd when need_resched() is true.
This can have a latency impact on stressed hosts.

[1] https://lore.kernel.org/lkml/20230325152417.5403-1-kerneljasonxing@gmail.com/
[2] https://lore.kernel.org/netdev/20230328142112.12493-1-kerneljasonxing@gmail.com/
====================

Link: https://lore.kernel.org/r/20230328235021.1048163-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 13:40:04 +02:00
Eric Dumazet
8b43fd3d1d net: optimize ____napi_schedule() to avoid extra NET_RX_SOFTIRQ
____napi_schedule() adds a napi into current cpu softnet_data poll_list,
then raises NET_RX_SOFTIRQ to make sure net_rx_action() will process it.

Idea of this patch is to not raise NET_RX_SOFTIRQ when being called indirectly
from net_rx_action(), because we can process poll_list from this point,
without going to full softirq loop.

This needs a change in net_rx_action() to make sure we restart
its main loop if sd->poll_list was updated without NET_RX_SOFTIRQ
being raised.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 13:40:00 +02:00
Eric Dumazet
821eba962d net: optimize napi_schedule_rps()
Based on initial patch from Jason Xing.

Idea is to not raise NET_RX_SOFTIRQ from napi_schedule_rps()
when we queued a packet into another cpu backlog.

We can do this only in the context of us being called indirectly
from net_rx_action(), to have the guarantee our rps_ipi_list
will be processed before we exit from net_rx_action().

Link: https://lore.kernel.org/lkml/20230325152417.5403-1-kerneljasonxing@gmail.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 13:40:00 +02:00
Eric Dumazet
c59647c0dc net: add softnet_data.in_net_rx_action
We want to make two optimizations in napi_schedule_rps() and
____napi_schedule() which require to know if these helpers are
called from net_rx_action(), instead of being called from
other contexts.

sd.in_net_rx_action is only read/written by the owning cpu.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 13:40:00 +02:00
Eric Dumazet
8fcb76b934 net: napi_schedule_rps() cleanup
napi_schedule_rps() return value is ignored, remove it.

Change the comment to clarify the intent.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Tested-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30 13:40:00 +02:00
Jakub Kicinski
7079d5e61a mlx5-updates-2023-03-28
Dragos Tatulea says:
 ====================
 
 net/mlx5e: RX, Drop page_cache and fully use page_pool
 
 For page allocation on the rx path, the mlx5e driver has been using an
 internal page cache in tandem with the page pool. The internal page
 cache uses a queue for page recycling which has the issue of head of
 queue blocking.
 
 This patch series drops the internal page_cache altogether and uses the
 page_pool to implement everything that was done by the page_cache
 before:
 * Let the page_pool handle dma mapping and unmapping.
 * Use fragmented pages with fragment counter instead of tracking via
   page ref.
 * Enable skb recycling.
 
 The patch series has the following effects on the rx path:
 
 * Improved performance for the cases when there was low page recycling
   due to head of queue blocking in the internal page_cache. The test
   for this was running a single iperf TCP stream to a rx queue
   which is bound on the same cpu as the application.
 
   |-------------+--------+--------+------+---------|
   | rq type     | before | after  | unit |   diff  |
   |-------------+--------+--------+------+---------|
   | striding rq |  30.1  |  31.4  | Gbps |  4.14 % |
   | legacy rq   |  30.2  |  33.0  | Gbps |  8.48 % |
   |-------------+--------+--------+------+---------|
 
 * Small XDP performance degradation. The test was is XDP drop
   program running on a single rx queue with small packets incoming
   it looks like this:
 
   |-------------+----------+----------+------+---------|
   | rq type     | before   | after    | unit |   diff  |
   |-------------+----------+----------+------+---------|
   | striding rq | 19725449 | 18544617 | pps  | -6.37 % |
   | legacy rq   | 19879931 | 18631841 | pps  | -6.70 % |
   |-------------+----------+----------+------+---------|
 
   This will be handled in a different patch series by adding support for
   multi-packet per page.
 
 * For other cases the performance is roughly the same.
 
 The above numbers were obtained on the following system:
   24 core Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz
   32 GB RAM
   ConnectX-7 single port
 
 The breakdown on the patch series is the following:
 * Preparations for introducing the mlx5e_frag_page struct.
 * Delete the mlx5e_page_cache struct.
 * Enable dma mapping from page_pool.
 * Enable skb recycling and fragment counting.
 * Do deferred release of pages (just before alloc) to ensure better
   page_pool cache utilization.
 
 ====================
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Merge tag 'mlx5-updates-2023-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5-updates-2023-03-28

Dragos Tatulea says:
====================

net/mlx5e: RX, Drop page_cache and fully use page_pool

For page allocation on the rx path, the mlx5e driver has been using an
internal page cache in tandem with the page pool. The internal page
cache uses a queue for page recycling which has the issue of head of
queue blocking.

This patch series drops the internal page_cache altogether and uses the
page_pool to implement everything that was done by the page_cache
before:
* Let the page_pool handle dma mapping and unmapping.
* Use fragmented pages with fragment counter instead of tracking via
  page ref.
* Enable skb recycling.

The patch series has the following effects on the rx path:

* Improved performance for the cases when there was low page recycling
  due to head of queue blocking in the internal page_cache. The test
  for this was running a single iperf TCP stream to a rx queue
  which is bound on the same cpu as the application.

  |-------------+--------+--------+------+---------|
  | rq type     | before | after  | unit |   diff  |
  |-------------+--------+--------+------+---------|
  | striding rq |  30.1  |  31.4  | Gbps |  4.14 % |
  | legacy rq   |  30.2  |  33.0  | Gbps |  8.48 % |
  |-------------+--------+--------+------+---------|

* Small XDP performance degradation. The test was is XDP drop
  program running on a single rx queue with small packets incoming
  it looks like this:

  |-------------+----------+----------+------+---------|
  | rq type     | before   | after    | unit |   diff  |
  |-------------+----------+----------+------+---------|
  | striding rq | 19725449 | 18544617 | pps  | -6.37 % |
  | legacy rq   | 19879931 | 18631841 | pps  | -6.70 % |
  |-------------+----------+----------+------+---------|

  This will be handled in a different patch series by adding support for
  multi-packet per page.

* For other cases the performance is roughly the same.

The above numbers were obtained on the following system:
  24 core Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz
  32 GB RAM
  ConnectX-7 single port

The breakdown on the patch series is the following:
* Preparations for introducing the mlx5e_frag_page struct.
* Delete the mlx5e_page_cache struct.
* Enable dma mapping from page_pool.
* Enable skb recycling and fragment counting.
* Do deferred release of pages (just before alloc) to ensure better
  page_pool cache utilization.

====================

* tag 'mlx5-updates-2023-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
  net/mlx5e: RX, Remove unnecessary recycle parameter and page_cache stats
  net/mlx5e: RX, Break the wqe bulk refill in smaller chunks
  net/mlx5e: RX, Increase WQE bulk size for legacy rq
  net/mlx5e: RX, Split off release path for xsk buffers for legacy rq
  net/mlx5e: RX, Defer page release in legacy rq for better recycling
  net/mlx5e: RX, Change wqe last_in_page field from bool to bit flags
  net/mlx5e: RX, Defer page release in striding rq for better recycling
  net/mlx5e: RX, Rename xdp_xmit_bitmap to a more generic name
  net/mlx5e: RX, Enable skb page recycling through the page_pool
  net/mlx5e: RX, Enable dma map and sync from page_pool allocator
  net/mlx5e: RX, Remove internal page_cache
  net/mlx5e: RX, Store SHAMPO header pages in array
  net/mlx5e: RX, Remove alloc unit layout constraint for striding rq
  net/mlx5e: RX, Remove alloc unit layout constraint for legacy rq
  net/mlx5e: RX, Remove mlx5e_alloc_unit argument in page allocation
====================

Link: https://lore.kernel.org/r/20230328205623.142075-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-29 22:15:24 -07:00
Simon Horman
c5370374bb net: ena: removed unused tx_bytes variable
clang 16.0.0 with W=1 reports:

drivers/net/ethernet/amazon/ena/ena_netdev.c:1901:6: error: variable 'tx_bytes' set but not used [-Werror,-Wunused-but-set-variable]
        u32 tx_bytes = 0;

The variable is not used so remove it.

Signed-off-by: Simon Horman <horms@kernel.org>
Acked-by: Shay Agroskin <shayagr@amazon.com>
Link: https://lore.kernel.org/r/20230328151958.410687-1-horms@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-29 21:39:35 -07:00
Dan Carpenter
765f360464 octeon_ep: unlock the correct lock on error path
The h and the f letters are swapped so it unlocks the wrong lock.

Fixes: 577f0d1b1c ("octeon_ep: add separate mailbox command and response queues")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/251aa2a2-913e-4868-aac9-0a90fc3eeeda@kili.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-29 21:39:35 -07:00
Tianfei Zhang
615927f1a4 ptp: add ToD device driver for Intel FPGA cards
Adding a DFL (Device Feature List) device driver of ToD device for
Intel FPGA cards.

The Intel FPGA Time of Day(ToD) IP within the FPGA DFL bus is exposed
as PTP Hardware clock(PHC) device to the Linux PTP stack to synchronize
the system clock to its ToD information using phc2sys utility of the
Linux PTP stack. The DFL is a hardware List within FPGA, which defines
a linked list of feature headers within the device MMIO space to provide
an extensible way of adding subdevice features.

Signed-off-by: Raghavendra Khadatare <raghavendrax.anand.khadatare@intel.com>
Signed-off-by: Tianfei Zhang <tianfei.zhang@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230328142455.481146-1-tianfei.zhang@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-29 21:25:48 -07:00
Hao Lan
3b064f541b net: hns3: support wake on lan configuration and query
The HNS3 driver supports Wake-on-LAN, which can wake up
the server from power off state to power on state by magic
packet or magic security packet.

ChangeLog:
v1->v2:
Deleted the debugfs function that overlaps with the ethtool function
from suggestion of Andrew Lunn.

v2->v3:
Return the wol configuration stored in driver,
suggested by Alexander H Duyck.

v3->v4:
Add a helper to go from netdev to the local struct,
suggested by Simon Horman and Jakub Kicinski.

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Hao Lan <lanhao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:07:42 +01:00
David S. Miller
be435af51f Merge branch 'sfc-tc-decap-support'
Edward Cree says:

====================
sfc: support TC decap rules

This series adds support for offloading tunnel decapsulation TC rules to
 ef100 NICs, allowing matching encapsulated packets to be decapsulated in
 hardware and redirected to VFs.
For now an encap match must be on precisely the following fields:
 ethertype (IPv4 or IPv6), source IP, destination IP, ipproto UDP,
 UDP destination port.  This simplifies checking for overlaps in the
 driver; the hardware supports a wider range of match fields which
 future driver work may expose.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:09 +01:00
Edward Cree
17654d84b4 sfc: add offloading of 'foreign' TC (decap) rules
A 'foreign' rule is one for which the net_dev is not the sfc netdevice
 or any of its representors.  The driver registers indirect flow blocks
 for tunnel netdevs so that it can offload decap rules.  For example:

    tc filter add dev vxlan0 parent ffff: protocol ipv4 flower \
        enc_src_ip 10.1.0.2 enc_dst_ip 10.1.0.1 \
        enc_key_id 1000 enc_dst_port 4789 \
        action tunnel_key unset \
        action mirred egress redirect dev $REPRESENTOR

When notified of a rule like this, register an encap match on the IP
 and dport tuple (creating an Outer Rule table entry) and insert an MAE
 action rule to perform the decapsulation and deliver to the representee.

Moved efx_tc_delete_rule() below efx_tc_flower_release_encap_match() to
 avoid the need for a forward declaration.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
Edward Cree
746224cdef sfc: add code to register and unregister encap matches
Add a hashtable to detect duplicate and conflicting matches.  If match
 is not a duplicate, call MAE functions to add/remove it from OR table.
Calling code not added yet, so mark the new functions as unused.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
Edward Cree
2245eb0086 sfc: add functions to insert encap matches into the MAE
An encap match corresponds to an entry in the exact-match Outer Rule
 table; the lookup response includes the encap type (protocol) allowing
 the hardware to continue parsing into the inner headers.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
Edward Cree
b7f5e17b3b sfc: handle enc keys in efx_tc_flower_parse_match()
Translate the fields from flow dissector into struct efx_tc_match.
In efx_tc_flower_replace(), reject filters that match on them, because
 only 'foreign' filters (i.e. those for which the ingress dev is not
 the sfc netdev or any of its representors, e.g. a tunnel netdev) can
 use them.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
Edward Cree
b9d5c9b7d8 sfc: add notion of match on enc keys to MAE machinery
Extend the MAE caps check to validate that the hardware supports these
 outer-header matches where used by the driver.
Extend efx_mae_populate_match_criteria() to fill in the outer rule ID
 and VNI match fields.
Nothing yet populates these match fields, nor creates outer rules.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
Edward Cree
edd025ca08 sfc: document TC-to-EF100-MAE action translation concepts
Includes an explanation of the lifetime of the 'cursor' action-set `act`.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:06:08 +01:00
David S. Miller
37018b5a29 Merge branch 'macvlan-broadcast-queue-bypass'
Herbert Xu says:

====================
macvlan: Allow some packets to bypass broadcast queue

This patch series allows some packets to bypass the broadcast
queue on receive.  Currently all multicast packets are queued
on receive and then processed in a work queue.  This is to avoid
an unbounded amount of work occurring in the receive path, as
one broadcast packet could easily translate into 4,000 packets.

However, for multicast packets with just one receiver (possible
for IPv6 ND), this introduces unnecessary latency as the packet
will go to exactly one device.

This series allows such multicast packets to be processed inline.
It also adds a toggle which lets the admin control what threshold
to set between queueing and not queueing.  A follow-up patch for
iproute will be posted.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:03:33 +01:00
Herbert Xu
954d1fa1ac macvlan: Add netlink attribute for broadcast cutoff
Make the broadcast cutoff configurable through netlink.  Note
that macvlan is weird because there is no central device for
us to configure (the lowerdev could be anything).  So all the
options are duplicated over what could be thousands of child
devices.

IFLA_MACVLAN_BC_QUEUE_LEN took the approach of taking the maximum
of all child device settings.  This is unnecessary as we could
simply store the option in the port device and take the last
child device that gets updated as the value to use.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:03:32 +01:00
Herbert Xu
d45276e75e macvlan: Skip broadcast queue if multicast with single receiver
As it stands all broadcast and multicast packets are queued and
processed in a work queue.  This is so that we don't overwhelm
the receive softirq path by generating thousands of packets or
more (see commit 412ca1550c "macvlan: Move broadcasts into a
work queue").

As such all multicast packets will be delayed, even if they will
be received by a single macvlan device.  As using a workqueue
is not free in terms of latency, we should avoid this where possible.

This patch adds a new filter to determine which addresses should
be delayed and which ones won't.  This is done using a crude
counter of how many times an address has been added to the macvlan
port (ha->synced).  For now if an address has been added more than
once, then it will be considered to be broadcast.  This could be
tuned further by making this threshold configurable.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:03:32 +01:00
David S. Miller
6fc5f5bcc0 Merge branch 'mptcp-cleanups'
Matthieu Baerts says:

====================
mptcp: a couple of cleanups and improvements

Patch 1 removes an unneeded address copy in subflow_syn_recv_sock().

Patch 2 simplifies subflow_syn_recv_sock() to postpone some actions and
to avoid a bunch of conditionals.

Patch 3 stops reporting limits that are not taken into account when the
userspace PM is used.

Patch 4 adds a new test to validate that the 'subflows' field reported
by the kernel is correct. Such info can be retrieved via Netlink (e.g.
with ss) or getsockopt(SOL_MPTCP, MPTCP_INFO).

---
Changes in v2:
- Patch 3/4's commit message has been updated to use the correct SHA
- Rebased on latest net-next
- Link to v1: https://lore.kernel.org/r/20230324-upstream-net-next-20230324-misc-features-v1-0-5a29154592bd@tessares.net
====================

Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:01:28 +01:00
Geliang Tang
9095ce97bf selftests: mptcp: add mptcp_info tests
This patch adds the mptcp_info fields tests in endpoint_tests(). Add a
new function chk_mptcp_info() to check the given number of the given
mptcp_info field.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/330
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:01:28 +01:00
Matthieu Baerts
e925a0322a mptcp: do not fill info not used by the PM in used
Only the in-kernel PM uses the number of address and subflow limits
allowed per connection.

It then makes more sense not to display such info when other PMs are
used not to confuse the userspace by showing limits not being used.

While at it, we can get rid of the "val" variable and add indentations
instead.

It would have been good to have done this modification directly in
commit 4d25247d3a ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs")
but as we change a bit the behaviour, it is fine not to backport it to
stable.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:01:28 +01:00
Paolo Abeni
a88d0092b2 mptcp: simplify subflow_syn_recv_sock()
Postpone the msk cloning to the child process creation
so that we can avoid a bunch of conditionals.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/61
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:01:28 +01:00
Paolo Abeni
2bb9a37f0e mptcp: avoid unneeded address copy
In the syn_recv fallback path, the msk is unused. We can skip
setting the socket address.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 09:01:28 +01:00
David S. Miller
9380d89104 Merge branch 'in6addr_any-cleanups'
Kuniyuki Iwashima says:

====================
ipv6: Random cleanup for in6addr_any.

The first patch removes in6addr_any alternatives and the second
removes redundant initialisation of a local variable.

Changes:
  v2: Use ipv6_addr_any() in patch 1. (David Ahern)

  v1: https://lore.kernel.org/netdev/20230322012204.33157-1-kuniyu@amazon.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:22:52 +01:00
Kuniyuki Iwashima
be689c719e 6lowpan: Remove redundant initialisation.
We'll call memset(&tmp, 0, sizeof(tmp)) later.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:22:52 +01:00
Kuniyuki Iwashima
8cdc3223e7 ipv6: Remove in6addr_any alternatives.
Some code defines the IPv6 wildcard address as a local variable and
use it with memcmp() or ipv6_addr_equal().

Let's use in6addr_any and ipv6_addr_any() instead.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:22:52 +01:00
David S. Miller
5a8c8b72f6 Merge branch 'vsock-sockmap-support'
Bobby Eshleman says:

====================
Add support for sockmap to vsock.

We're testing usage of vsock as a way to redirect guest-local UDS
requests to the host and this patch series greatly improves the
performance of such a setup.

Compared to copying packets via userspace, this improves throughput by
121% in basic testing.

Tested as follows.

Setup: guest unix dgram sender -> guest vsock redirector -> host vsock
       server
Threads: 1
Payload: 64k
No sockmap:
- 76.3 MB/s
- The guest vsock redirector was
  "socat VSOCK-CONNECT:2:1234 UNIX-RECV:/path/to/sock"
Using sockmap (this patch):
- 168.8 MB/s (+121%)
- The guest redirector was a simple sockmap echo server,
  redirecting unix ingress to vsock 2:1234 egress.
- Same sender and server programs

*Note: these numbers are from RFC v1

Only the virtio transport has been tested. The loopback transport was
used in writing bpf/selftests, but not thoroughly tested otherwise.

This series requires the skb patch.

Changes in v4:
- af_vsock: fix parameter alignment in vsock_dgram_recvmsg()
- af_vsock: add TCP_ESTABLISHED comment in vsock_dgram_connect()
- vsock/bpf: change ret type to bool

Changes in v3:
- vsock/bpf: Refactor wait logic in vsock_bpf_recvmsg() to avoid
  backwards goto
- vsock/bpf: Check psock before acquiring slock
- vsock/bpf: Return bool instead of int of 0 or 1
- vsock/bpf: Wrap macro args __sk/__psock in parens
- vsock/bpf: Place comment trailer */ on separate line

Changes in v2:
- vsock/bpf: rename vsock_dgram_* -> vsock_*
- vsock/bpf: change sk_psock_{get,put} and {lock,release}_sock() order
  to minimize slock hold time
- vsock/bpf: use "new style" wait
- vsock/bpf: fix bug in wait log
- vsock/bpf: add check that recvmsg sk_type is one dgram, seqpacket, or
  stream.  Return error if not one of the three.
- virtio/vsock: comment __skb_recv_datagram() usage
- virtio/vsock: do not init copied in read_skb()
- vsock/bpf: add ifdef guard around struct proto in dgram_recvmsg()
- selftests/bpf: add vsock loopback config for aarch64
- selftests/bpf: add vsock loopback config for s390x
- selftests/bpf: remove vsock device from vmtest.sh qemu machine
- selftests/bpf: remove CONFIG_VIRTIO_VSOCKETS=y from config.x86_64
- vsock/bpf: move transport-related (e.g., if (!vsk->transport)) checks
  out of fast path
====================

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:19:38 +01:00
Bobby Eshleman
d61bd8c1fd selftests/bpf: add a test case for vsock sockmap
Add a test case testing the redirection from connectible AF_VSOCK
sockets to connectible AF_UNIX sockets.

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:19:38 +01:00
Bobby Eshleman
c7c605c982 selftests/bpf: add vsock to vmtest.sh
Add vsock loopback to the test kernel.

This allows sockmap for vsock to be tested.

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:19:38 +01:00
Bobby Eshleman
634f1a7110 vsock: support sockmap
This patch adds sockmap support for vsock sockets. It is intended to be
usable by all transports, but only the virtio and loopback transports
are implemented.

SOCK_STREAM, SOCK_DGRAM, and SOCK_SEQPACKET are all supported.

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:19:38 +01:00
Bobby Eshleman
24265c2c91 testing/vsock: add vsock_perf to gitignore
This adds the vsock_perf binary to the gitignore file.

Fixes: 8abbffd27c ("test/vsock: vsock_perf utility")
Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Reviewed-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20230327-vsock-add-vsock-perf-to-ignore-v1-1-f28a84f3606b@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:55:22 -07:00
Jakub Kicinski
35fae44e8e Merge branch 'ynl-add-support-for-user-headers-and-struct-attrs'
Donald Hunter says:

====================
ynl: add support for user headers and struct attrs

Add support for user headers and struct attrs to YNL. This patchset adds
features to ynl and add a partial spec for openvswitch that demonstrates
use of the features.

Patch 1-4 add features to ynl
Patch 5 adds partial openvswitch specs that demonstrate the new features
Patch 6-7 add documentation for legacy structs and for sub-type
====================

Link: https://lore.kernel.org/r/20230327083138.96044-1-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:45 -07:00
Donald Hunter
04eac39361 docs: netlink: document the sub-type attribute property
Add a definition for sub-type to the protocol spec doc and a description of
its usage for C arrays in genetlink-legacy.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
88e2889684 docs: netlink: document struct support for genetlink-legacy
Describe the genetlink-legacy support for using struct definitions
for fixed headers and for binary attributes.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
643ef4a676 netlink: specs: add partial specification for openvswitch
The openvswitch family has a fixed header, uses struct attrs and has array
values. This partial spec demonstrates these features in the YNL CLI. These
specs are sufficient to create, delete and dump datapaths and to dump vports:

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ovs_datapath.yaml \
    --do dp-new --json '{ "dp-ifindex": 0, "name": "demo", "upcall-pid": 0}'
None

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ovs_datapath.yaml \
    --dump dp-get --json '{ "dp-ifindex": 0 }'
[{'dp-ifindex': 3,
  'masks-cache-size': 256,
  'megaflow-stats': {'cache-hits': 0,
                     'mask-hit': 0,
                     'masks': 0,
                     'pad1': 0,
                     'padding': 0},
  'name': 'test',
  'stats': {'flows': 0, 'hit': 0, 'lost': 0, 'missed': 0},
  'user-features': {'dispatch-upcall-per-cpu',
                    'tc-recirc-sharing',
                    'unaligned'}},
 {'dp-ifindex': 48,
  'masks-cache-size': 256,
  'megaflow-stats': {'cache-hits': 0,
                     'mask-hit': 0,
                     'masks': 0,
                     'pad1': 0,
                     'padding': 0},
  'name': 'demo',
  'stats': {'flows': 0, 'hit': 0, 'lost': 0, 'missed': 0},
  'user-features': set()}]

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ovs_datapath.yaml \
    --do dp-del --json '{ "dp-ifindex": 0, "name": "demo"}'
None

$ ./tools/net/ynl/cli.py \
    --spec Documentation/netlink/specs/ovs_vport.yaml \
    --dump vport-get --json '{ "dp-ifindex": 3 }'
[{'dp-ifindex': 3,
  'ifindex': 3,
  'name': 'test',
  'port-no': 0,
  'stats': {'rx-bytes': 0,
            'rx-dropped': 0,
            'rx-errors': 0,
            'rx-packets': 0,
            'tx-bytes': 0,
            'tx-dropped': 0,
            'tx-errors': 0,
            'tx-packets': 0},
  'type': 'internal',
  'upcall-pid': [0],
  'upcall-stats': {'fail': 0, 'success': 0}}]

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
f036d936ca tools: ynl: Add fixed-header support to ynl
Add support for netlink families that add an optional fixed header structure
after the genetlink header and before any attributes. The fixed-header can be
specified on a per op basis, or once for all operations, which serves as a
default value that can be overridden.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
2607191395 tools: ynl: Add struct attr decoding to ynl
Add support for decoding attributes that contain C structs.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
b423c3c863 tools: ynl: Add C array attribute decoding to ynl
Add support for decoding C arrays from binay blobs in genetlink-legacy
messages.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Donald Hunter
bec0b7a2db tools: ynl: Add struct parsing to nlspec
Add python classes for struct definitions to nlspec

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:54:43 -07:00
Jakub Kicinski
de7494524d mlx5-updates-2023-03-20
mlx5 dynamic msix
 
 This patch series adds support for dynamic msix vectors allocation in mlx5.
 
 Eli Cohen Says:
 
 ================
 
 The following series of patches modifies mlx5_core to work with the
 dynamic MSIX API. Currently, mlx5_core allocates all the interrupt
 vectors it needs and distributes them amongst the consumers. With the
 introduction of dynamic MSIX support, which allows for allocation of
 interrupts more than once, we now allocate vectors as we need them.
 This allows other drivers running on top of mlx5_core to allocate
 interrupt vectors for their own use. An example for this is mlx5_vdpa,
 which uses these vectors to propagate interrupts directly from the
 hardware to the vCPU [1].
 
 As a preparation for using this series, a use after free issue is fixed
 in lib/cpu_rmap.c and the allocator for rmap entries has been modified.
 A complementary API for irq_cpu_rmap_add() has also been introduced.
 
 [1] https://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux.git/patch/?id=0f2bf1fcae96a83b8c5581854713c9fc3407556e
 
 ================
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Merge tag 'mlx5-updates-2023-03-20' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5-updates-2023-03-20

mlx5 dynamic msix

This patch series adds support for dynamic msix vectors allocation in mlx5.

Eli Cohen Says:

================

The following series of patches modifies mlx5_core to work with the
dynamic MSIX API. Currently, mlx5_core allocates all the interrupt
vectors it needs and distributes them amongst the consumers. With the
introduction of dynamic MSIX support, which allows for allocation of
interrupts more than once, we now allocate vectors as we need them.
This allows other drivers running on top of mlx5_core to allocate
interrupt vectors for their own use. An example for this is mlx5_vdpa,
which uses these vectors to propagate interrupts directly from the
hardware to the vCPU [1].

As a preparation for using this series, a use after free issue is fixed
in lib/cpu_rmap.c and the allocator for rmap entries has been modified.
A complementary API for irq_cpu_rmap_add() has also been introduced.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux.git/patch/?id=0f2bf1fcae96a83b8c5581854713c9fc3407556e

================

* tag 'mlx5-updates-2023-03-20' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
  net/mlx5: Provide external API for allocating vectors
  net/mlx5: Use one completion vector if eth is disabled
  net/mlx5: Refactor calculation of required completion vectors
  net/mlx5: Move devlink registration before mlx5_load
  net/mlx5: Use dynamic msix vectors allocation
  net/mlx5: Refactor completion irq request/release code
  net/mlx5: Improve naming of pci function vectors
  net/mlx5: Use newer affinity descriptor
  net/mlx5: Modify struct mlx5_irq to use struct msi_map
  net/mlx5: Fix wrong comment
  net/mlx5e: Coding style fix, add empty line
  lib: cpu_rmap: Add irq_cpu_rmap_remove to complement irq_cpu_rmap_add
  lib: cpu_rmap: Use allocator for rmap entries
  lib: cpu_rmap: Avoid use after free on rmap->obj array entries
====================

Link: https://lore.kernel.org/r/20230324231341.29808-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:52:12 -07:00
Jakub Kicinski
e70f94c6c7 docs: netdev: clarify the need to sending reverts as patches
We don't state explicitly that reverts need to be submitted
as a patch. It occasionally comes up.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230327172646.2622943-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:51:05 -07:00
Tom Rix
e48cefb9c8 net: ethernet: 8390: axnet_cs: remove unused xfer_count variable
clang with W=1 reports
drivers/net/ethernet/8390/axnet_cs.c:653:9: error: variable
  'xfer_count' set but not used [-Werror,-Wunused-but-set-variable]
    int xfer_count = count;
        ^
This variable is not used so remove it.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230327235423.1777590-1-trix@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 23:48:02 -07:00
Wolfram Sang
cdeccd13a0 Revert "sh_eth: remove open coded netif_running()"
This reverts commit ce1fdb0656. It turned
out this actually introduces a race condition. netif_running() is not a
suitable check for get_stats.

Reported-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230327152112.15635-1-wsa+renesas@sang-engineering.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 19:23:32 -07:00
Jakub Kicinski
2600badfea Merge branch 'net-refcount-address-dst_entry-reference-count-scalability-issues'
Thomas Gleixner says:

====================
net, refcount: Address dst_entry reference count scalability issues

This is version 3 of this series. Version 2 can be found here:

     https://lore.kernel.org/lkml/20230307125358.772287565@linutronix.de

Wangyang and Arjan reported a bottleneck in the networking code related to
struct dst_entry::__refcnt. Performance tanks massively when concurrency on
a dst_entry increases.

This happens when there are a large amount of connections to or from the
same IP address. The memtier benchmark when run on the same host as
memcached amplifies this massively. But even over real network connections
this issue can be observed at an obviously smaller scale (due to the
network bandwith limitations in my setup, i.e. 1Gb). How to reproduce:

  Run memcached with -t $N and memtier_benchmark with -t $M and --ratio=1:100
  on the same machine. localhost connections amplify the problem.

  Start with the defaults for $N and $M and increase them. Depending on
  your machine this will tank at some point. But even in reasonably small
  $N, $M scenarios the refcount operations and the resulting false sharing
  fallout becomes visible in perf top. At some point it becomes the
  dominating issue.

There are two factors which make this reference count a scalability issue:

   1) False sharing

      dst_entry:__refcnt is located at offset 64 of dst_entry, which puts
      it into a seperate cacheline vs. the read mostly members located at
      the beginning of the struct.

      That prevents false sharing vs. the struct members in the first 64
      bytes of the structure, but there is also

      	    dst_entry::lwtstate

      which is located after the reference count and in the same cache
      line. This member is read after a reference count has been acquired.

      The other problem is struct rtable, which embeds a struct dst_entry
      at offset 0. struct dst_entry has a size of 112 bytes, which means
      that the struct members of rtable which follow the dst member share
      the same cache line as dst_entry::__refcnt. Especially

      	  rtable::rt_genid

      is also read by the contexts which have a reference count acquired
      already.

      When dst_entry:__refcnt is incremented or decremented via an atomic
      operation these read accesses stall and contribute to the performance
      problem.

   2) atomic_inc_not_zero()

      A reference on dst_entry:__refcnt is acquired via
      atomic_inc_not_zero() and released via atomic_dec_return().

      atomic_inc_not_zero() is implemted via a atomic_try_cmpxchg() loop,
      which exposes O(N^2) behaviour under contention with N concurrent
      operations. Contention scalability is degrading with even a small
      amount of contenders and gets worse from there.

      Lightweight instrumentation exposed an average of 8!! retry loops per
      atomic_inc_not_zero() invocation in a inc()/dec() loop running
      concurrently on 112 CPUs.

      There is nothing which can be done to make atomic_inc_not_zero() more
      scalable.

The following series addresses these issues:

    1) Reorder and pad struct dst_entry to prevent the false sharing.

    2) Implement and use a reference count implementation which avoids the
       atomic_inc_not_zero() problem.

       It is slightly less performant in the case of the final 0 -> -1
       transition, but the deconstruction of these objects is a low
       frequency event. get()/put() pairs are in the hotpath and that's
       what this implementation optimizes for.

       The algorithm of this reference count is only suitable for RCU
       managed objects. Therefore it cannot replace the refcount_t
       algorithm, which is also based on atomic_inc_not_zero(), due to a
       subtle race condition related to the 0 -> -1 transition and the final
       verdict to mark the reference count dead. See details in patch 2/3.

       It might be just my lack of imagination which declares this to be
       impossible and I'd be happy to be proven wrong.

       As a bonus the new rcuref implementation provides underflow/overflow
       detection and mitigation while being performance wise on par with
       open coded atomic_inc_not_zero() / atomic_dec_return() pairs even in
       the non-contended case.

The combination of these two changes results in performance gains in micro
benchmarks and also localhost and networked memtier benchmarks talking to
memcached. It's hard to quantify the benchmark results as they depend
heavily on the micro-architecture and the number of concurrent operations.

The overall gain of both changes for localhost memtier ranges from 1.2X to
3.2X and from +2% to %5% range for networked operations on a 1Gb connection.

A micro benchmark which enforces maximized concurrency shows a gain between
1.2X and 4.7X!!!

Obviously this is focussed on a particular problem and therefore needs to
be discussed in detail. It also requires wider testing outside of the cases
which this is focussed on.

Though the false sharing issue is obvious and should be addressed
independent of the more focussed reference count changes.

The series is also available from git:

  git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git rcuref

Changes vs. V2:

  - Rename __refcnt to __rcuref (Linus)

  - Fix comments and changelogs (Mark, Qiuxu)

  - Fixup kernel doc of generated atomic_add_negative() variants

I want to say thanks to Wangyang who analyzed the issue and provided the
initial fix for the false sharing problem. Further thanks go to Arjan
Peter, Marc, Will and Borislav for valuable input and providing test
results on machines which I do not have access to, and to Linus and
Eric, Qiuxu and Mark for helpful feedback.
====================

Link: https://lore.kernel.org/r/20230323102649.764958589@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 18:53:43 -07:00
Thomas Gleixner
bc9d3a9f2a net: dst: Switch to rcuref_t reference counting
Under high contention dst_entry::__refcnt becomes a significant bottleneck.

atomic_inc_not_zero() is implemented with a cmpxchg() loop, which goes into
high retry rates on contention.

Switch the reference count to rcuref_t which results in a significant
performance gain. Rename the reference count member to __rcuref to reflect
the change.

The gain depends on the micro-architecture and the number of concurrent
operations and has been measured in the range of +25% to +130% with a
localhost memtier/memcached benchmark which amplifies the problem
massively.

Running the memtier/memcached benchmark over a real (1Gb) network
connection the conversion on top of the false sharing fix for struct
dst_entry::__refcnt results in a total gain in the 2%-5% range over the
upstream baseline.

Reported-by: Wangyang Guo <wangyang.guo@intel.com>
Reported-by: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230307125538.989175656@linutronix.de
Link: https://lore.kernel.org/r/20230323102800.215027837@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 18:52:28 -07:00