Saeed Mahameed says:

====================
mlx5-updates-2021-10-26

HW-GRO support in mlx5

Beside the HW GRO this series includes two trivial non-mlx5 patches:
 - net: Prevent HW-GRO and LRO features operate together
 - lib: bitmap: Introduce node-aware alloc API

Khalid Manaa Says:
==================
This series implements the HW-GRO offload using the HW feature SHAMPO.

HW-GRO: Hardware offload for the Generic Receive Offload feature.

SHAMPO: Split Headers And Merge Payload Offload.

This feature performs headers data split for each received packed and
merge the payloads of the packets of the same session.

There are new HW components for this feature:

The headers buffer:
– cyclic buffer where the packets headers will be located

Reservation buffer:
– capability to divide RQ WQEs to reservations, a definite size in
  granularity of 4KB, the reservation is used to define the largest segment
  that we can create by packets stitching.

Each reservation will have a session and the new received packet can be merged
to the session, terminate it, or open a new one according to the match criteria.

When a new packet is received the headers will be written to the headers buffer
and the data will be written to the reservation, in case the packet matches
the session the data will be written continuously otherwise it will be written
after performing an alignment.

SHAMPO RQ, WQ and CQE changes:
-----------------------------
RQ (receive queue) new params:

 -shampo_no_match_alignment_granularity: the HW alignment granularity in case
  the received packet doesn't match the current session.

 -shampo_match_criteria_type: the type of match criteria.

 -reservation_timeout: the maximum time that the HW will hold the reservation.

 -Each RQ has SKB that represents the current opened flow.

WQ (work queue) new params:

 -headers_mkey: mkey that represents the headers buffer, where the packets
  headers will be written by the HW.

 -shampo_enable: flag to verify if the WQ supports SHAMPO feature.

 -log_reservation_size: the log of the reservation size where the data of
  the packet will be written by the HW.

 -log_max_num_of_packets_per_reservation: log of the maximum number of packets
  that can be written to the same reservation.

 -log_headers_entry_size: log of the header entry size of the headers buffer.

 -log_headers_buffer_entry_num: log of the entries number of the headers buffer.

CQEs (Completion queue entry) SHAMPO fields:

 -match: in case it is set, then the current packet matches the opened session.

 -flush: in case it is set, the opened session must be flushed.

 -header_size: the size of the packet’s headers.

 -header_entry_index: the entry index in the headers buffer of the received
  packet headers.

 -data_offset: the offset of the received packet data in the WQE.

HW-GRO works as follow:
----------------------
The feature can be enabled on the interface using the ethtool command by
setting on rx-gro-hw. When the feature is on the mlx5 driver will reopen
the RQ to support the SHAMPO feature:

Will allocate the headers buffer and fill the parameters regarding the
reservation and the match criteria.

Receive packet flow:

each RQ will hold SKB that represents the current GRO opened session.

The driver has a new CQE handler mlx5e_handle_rx_cqe_mpwrq_shampo which will
use the CQE SHAMPO params to extract the location of the packet’s headers
in the headers buffer and the location of the packets data in the RQ.

Also, the CQE has two flags flush and match that indicate if the current
packet matches the current session or not and if we need to close the session.

In case there is an opened session, and we receive a matched packet then the
handler will merge the packet's payload to the current SKB, in case we receive
no match then the handler will flush the SKB and create a new one for the new packet.

In case the flash flag is set then the driver will close the session, the SKB
will be passed to the network stack.

In case the driver merges packets in the SKB, before passing the SKB to the network
stack the driver will update the checksum of the packet’s headers.

SKB build:
---------
The driver will build a new SKB in the following situations:
in case there is no current opened session.
In case the current packet doesn’t match the current session.
In case there is no place to add the packets data to the SKB that represents the
current session.

Otherwise, the driver will add the packet’s data to the SKB.

When the driver builds a new SKB, the linear area will contain only the packet headers
and the data will be added to the SKB fragments.

In case the entry size of the headers buffer is sufficient to build the SKB
it will be used, otherwise the driver will allocate new memory to build the SKB.

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

====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix "no previous prototype" W=1 warnings when CONFIG_MLX5_CORE_EN is not set:

  drivers/net/ethernet/mellanox/mlx5/core/lag_mp.h:34:6: error: no previous prototype for ‘mlx5_lag_is_multipath’ [-Werror=missing-prototypes]
     34 | bool mlx5_lag_is_multipath(struct mlx5_core_dev *dev) { return false; }
        |      ^~~~~~~~~~~~~~~~~~~~~

Fixes: 14fe2471 ("net/mlx5: Lag, change multipath and bonding to be mutually exclusive")
Signed-off-by: Maor Dickman <maord@nvidia.com>

HW-GRO and CQE-COMPRESS are mutually exclusive, this commit adds this
restriction.
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This commit introduces HW-GRO offload by using the SHAMPO feature
- Add set feature handler for HW-GRO.
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This patch adds HW_GRO counters to RX packets statistics:
 - gro_match_packets: counter of received packets with set match flag.

 - gro_packets: counter of received packets over the HW_GRO feature,
                this counter is increased by one for every received
                HW_GRO cqe.

 - gro_bytes: counter of received bytes over the HW_GRO feature,
              this counter is increased by the received bytes for every
              received HW_GRO cqe.

 - gro_skbs: counter of built HW_GRO skbs,
             increased by one when we flush HW_GRO skb
             (when we call a napi_gro_receive with hw_gro skb).

 - gro_large_hds: counter of received packets with large headers size,
                  in case the packet needs new SKB, the driver will allocate
                  new one and will not use the headers entry to build it.
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

this patch updates the SHAMPO CQE handler to support HW_GRO,

changes in the SHAMPO CQE handler:
- CQE match and flush fields are used to determine if to build new skb
  using the new received packet,
  or to add the received packet data to the existing RQ.hw_gro_skb,
  also this fields are used to determine when to flush the skb.
- in the end of the function mlx5e_poll_rx_cq the RQ.hw_gro_skb is flushed.
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

The header buffer is used to store the headers of the rx packets.
The header buffer size deduced from WorkQueue size + restriction
of max packets per WorkQueueElement.
This commit adds the functionality for posting/updating memory for
the header buffer during the posting/updating of WQEs.
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This patch adds the new CQE SHAMPO fields:
- flush: indicates that we must close the current session and pass the SKB
         to the network stack.

- match: indicates that the current packet matches the oppened session,
         the packet will be merge into the current SKB.

- header_size: the size of the packet headers that written into the headers
               buffer.

- header_entry_index: the entry index in the headers buffer.

- data_offset: packets data offset in the WQE.

Also new cqe handler is added to handle SHAMPO packets:
- The new handler uses CQE SHAMPO fields to build the SKB.
  CQE's Flush and match fields are not used in this patch, packets are not
  merged in this patch.
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This commit introduces the control path infrastructure for SHAMPO feature.

SHAMPO feature enables packet stitching by splitting packets to
header and payload, the header is placed on a dedicated buffer
and the payload on the RX ring, this allows stitching the data part
of a flow together continuously in the receive buffer.

SHAMPO feature is implemented as linked list striding RQ feature.
To support packets splitting and payload stitching:
- Enlarge the ICOSQ and the correspond CQ to support the header buffer
  memory regions.
- Add support to create linked list striding RQ with SHAMPO feature set
  in the open_rq function.
- Add deallocation function and corresponded calls for SHAMPO header
  buffer.
- Add mlx5e_create_umr_klm_mkey to support KLM mkey for the header
  buffer.
- Rename mlx5e_create_umr_mkey to mlx5e_create_umr_mtt_mkey.
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This commit adds the needed definitions for using the klm_umr_wqe.
UMR stands for user-mode memory registration, is a mechanism to alter
address translation properties of MKEY by posting WorkQueueElement
aka WQE on send queue.
MKEY stands for memory key, MKEY are used to describe a region in memory that
can be later used by HW.
KLM stands for {Key, Length, MemVa}, KLM_MKEY is indirect MKEY that enables
to map multiple memory spaces with different sizes in unified MKEY.
klm_umr_wqe is a UMR that use to update a KLM_MKEY.
SHAMPO feature uses KLM_MKEY for memory registration of his header buffer.
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This series introduces new packet merge type, therefore rename lro
functions to packet merge to support the new merge type:
- Generalize + rename mlx5e_build_tir_ctx_lro to
  mlx5e_build_tir_ctx_packet_merge.
- Rename mlx5e_modify_tirs_lro to mlx5e_modify_tirs_packet_merge.
- Rename lro bit in mlx5_ifc_modify_tir_bitmask_bits to packet_merge.
- Rename lro_en in mlx5e_params to packet_merge_type type and combine
  packet_merge params into one struct mlx5e_packet_merge_param.
Signed-off-by: Khalid Manaa <khalidm@nvidia.com>
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

This commit adds SHAMPO bit to hca_cap and SHAMPO capabilities structure,
SHAMPO related HW spec hardware fields and enumerations.
SHAMPO stands for: split headers and merge payload offload.
SHAMPO new fields:
WQ:
 - headers_mkey: mkey that represents the headers buffer, where the packets
   headers will be written by the HW.

 - shampo_enable: flag to verify if the WQ supports SHAMPO feature.

 - log_reservation_size: the log of the reservation size where the data of
   the packet will be written by the HW.

 - log_max_num_of_packets_per_reservation: log of the maximum number of
   packets that can be written to the same reservation.

 - log_headers_entry_size: log of the header entry size of the headers buffer.

 - log_headers_buffer_entry_num: log of the entries number of the headers buffer.

RQ:
 - shampo_no_match_alignment_granularity: the HW alignment granularity
   in case the received packet doesn't match the current session.

 - shampo_match_criteria_type: the type of match criteria.

 - reservation_timeout: the maximum time that the HW will hold the
   reservation.

mlx5_ifc_shampo_cap_bits, the capabilities of the SHAMPO feature:
 - shampo_log_max_reservation_size: the maximum allowed value of the field
   WQ.log_reservation_size.

 - log_reservation_size: the minimum allowed value of the field
   WQ.log_reservation_size.

 - shampo_min_mss_size: the minimum payload size of packet that can open
   a new session or be merged to a session.

 - shampo_max_log_headers_entry_size: the maximum allowed value of the field
   WQ.log_headers_entry_size
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

TIR stands for transport interface receive, the TIR object is
responsible for performing all transport related operations on
the receive side like packet processing, demultiplexing the packets
to different RQ's, etc.
lro_timeout is a field in the TIR that is used to set the timeout for lro
session, this series introduces new packet merge type, therefore rename
lro_timeout to packet_merge_timeout for all packet merge types.
Signed-off-by: Ben Ben-Ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

LRO and HW-GRO are mutually exclusive, this commit adds this restriction
in netdev_fix_feature. HW-GRO is preferred, that means in case both
HW-GRO and LRO features are requested, LRO is cleared.
Signed-off-by: Ben Ben-ishay <benishay@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Expose new node-aware API for bitmap allocation:
bitmap_alloc_node() / bitmap_zalloc_node().
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Fixed warning: Function parameter or member 'enable' not
described in 'genphy_c45_fast_retrain'
Signed-off-by: Luo Jie <luoj@codeaurora.org>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20211026102957.17100-1-luoj@codeaurora.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

revert commit 46ae40b9 ("net/mlx5: Let user configure io_eq_size param")
revert commit a6cb08da ("net/mlx5: Let user configure event_eq_size param")
revert commit 55460406 ("net/mlx5: Let user configure max_macs param")

The EQE parameters are applicable to more drivers, they should
be configured via standard API, probably ethtool. Example of
another driver needing something similar:

https://lore.kernel.org/all/1633454136-14679-3-git-send-email-sbhatta@marvell.com/

The last param for "max_macs" is probably fine but the documentation
is severely lacking. The meaning and implications for changing the
param need to be stated.

Link: https://lore.kernel.org/r/20211026152939.3125950-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Russell King says:

====================
Introduce supported interfaces bitmap

This series introduces a new bitmap to allow us to indicate which
phy_interface_t modes are supported.

Currently, phylink will call ->validate with PHY_INTERFACE_MODE_NA to
request all link mode capabilities from the MAC driver before choosing
an interface to use. This leads in some cases to some rather hairly
code. This can be simplified if phylink is aware of the interface modes
that  the MAC supports, and it can instead walk those modes, calling
->validate for each one, and combining the results.

This series merely introduces the support; there is no change of
behaviour until MAC drivers populate their supported_interfaces bitmap.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

If the network device supplies a supported interface bitmap, we can use
that during phylink's validation to simplify MAC drivers in two ways by
using the supported_interfaces bitmap to:

1. reject unsupported interfaces before calling into the MAC driver.
2. generate the set of all supported link modes across all supported
   interfaces (used mainly for SFP, but also some 10G PHYs.)
Suggested-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a phy_interface_t bitmap so the MAC driver can specifiy which PHY
interface modes it supports.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for a bitmap for phy interface modes, which includes:
- a macro to declare the interface bitmap
- an inline helper to zero the interface bitmap
- an inline helper to detect an empty interface bitmap
- inline helpers to do a bitwise AND and OR operations on two interface
  bitmaps
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vladimir Oltean says:

====================
DSA preparations for FDB isolation between bridges

This series makes 2 small changes to DSA's SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE
handler, which will make it possible to offer switch drivers a stable
association between a FDB entry and a bridge device in a future series.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that we guarantee that SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE events have
finished executing by the time we leave our bridge upper interface,
we've established a stronger boundary condition for how long the
dsa_slave_switchdev_event_work() might run.

As such, it is no longer possible for DSA slave interfaces to become
unregistered, since they are still bridge ports.

So delete the unnecessary dev_hold() and dev_put().
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

DSA is preparing to offer switch drivers an API through which they can
associate each FDB entry with a struct net_device *bridge_dev. This can
be used to perform FDB isolation (the FDB lookup performed on the
ingress of a standalone, or bridged port, should not find an FDB entry
that is present in the FDB of another bridge).

In preparation of that work, DSA needs to ensure that by the time we
call the switch .port_fdb_add and .port_fdb_del methods, the
dp->bridge_dev pointer is still valid, i.e. the port is still a bridge
port.

This is not guaranteed because the SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE API
requires drivers that must have sleepable context to handle those events
to schedule the deferred work themselves. DSA does this through the
dsa_owq.

It can happen that a port leaves a bridge, del_nbp() flushes the FDB on
that port, SWITCHDEV_FDB_DEL_TO_DEVICE is notified in atomic context,
DSA schedules its deferred work, but del_nbp() finishes unlinking the
bridge as a master from the port before DSA's deferred work is run.

Fundamentally, the port must not be unlinked from the bridge until all
FDB deletion deferred work items have been flushed. The bridge must wait
for the completion of these hardware accesses.

An attempt has been made to address this issue centrally in switchdev by
making SWITCHDEV_FDB_DEL_TO_DEVICE deferred (=> blocking) at the switchdev
level, which would offer implicit synchronization with del_nbp:

https://patchwork.kernel.org/project/netdevbpf/cover/20210820115746.3701811-1-vladimir.oltean@nxp.com/

but it seems that any attempt to modify switchdev's behavior and make
the events blocking there would introduce undesirable side effects in
other switchdev consumers.

The most undesirable behavior seems to be that
switchdev_deferred_process_work() takes the rtnl_mutex itself, which
would be worse off than having the rtnl_mutex taken individually from
drivers which is what we have now (except DSA which has removed that
lock since commit 0faf890f ("net: dsa: drop rtnl_lock from
dsa_slave_switchdev_event_work")).

So to offer the needed guarantee to DSA switch drivers, I have come up
with a compromise solution that does not require switchdev rework:
we already have a hook at the last moment in time when the bridge is
still an upper of ours: the NETDEV_PRECHANGEUPPER handler. We can flush
the dsa_owq manually from there, which makes all FDB deletions
synchronous.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

IFB originally depended on NET_CLS_ACT for traffic redirection.
But since v4.5, that may be achieved with NFT_FWD_NETDEV as well.

Fixes: 39e6dea2 ("netfilter: nf_tables: add forward expression to the netdev family")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v4.5+: bcfabee1: netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: David S. Miller <davem@davemloft.net>

This change allows an extended address struct - struct sockaddr_mctp_ext
- to be passed to sendmsg/recvmsg. This allows userspace to specify
output ifindex and physical address information (for sendmsg) or receive
the input ifindex/physaddr for incoming messages (for recvmsg). This is
typically used by userspace for MCTP address discovery and assignment
operations.

The extended addressing facility is conditional on a new sockopt:
MCTP_OPT_ADDR_EXT; userspace must explicitly enable addressing before
the kernel will consume/populate the extended address data.

Includes a fix for an uninitialised var:
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clang warns:

drivers/net/ethernet/asix/ax88796c_main.c:851:24: error: address of
array 'ax_local->phydev->advertising' will always evaluate to 'true'
[-Werror,-Wpointer-bool-conversion]
        if (ax_local->phydev->advertising &&
            ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~ ~~

advertising cannot be NULL here if ax_local is not NULL, which cannot
happen due to the check in ax88796c_probe(). Remove the check.

Link: https://github.com/ClangBuiltLinux/linux/issues/1492Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clang warns:

drivers/net/ethernet/asix/ax88796c_main.c:696:2: error: unannotated fall-through between switch labels [-Werror,-Wimplicit-fallthrough]
        case SPEED_10:
        ^
drivers/net/ethernet/asix/ax88796c_main.c:696:2: note: insert 'break;' to avoid fall-through
        case SPEED_10:
        ^
        break;
drivers/net/ethernet/asix/ax88796c_main.c:706:2: error: unannotated fall-through between switch labels [-Werror,-Wimplicit-fallthrough]
        case DUPLEX_HALF:
        ^
drivers/net/ethernet/asix/ax88796c_main.c:706:2: note: insert 'break;' to avoid fall-through
        case DUPLEX_HALF:
        ^
        break;

Clang is a little more pedantic than GCC, which permits implicit
fallthroughs to cases that contain just break or return. Clang's version
is more in line with the kernel's own stance in deprecated.rst, which
states that all switch/case blocks must end in either break,
fallthrough, continue, goto, or return. Add the missing breaks to fix
the warning.

Link: https://github.com/ClangBuiltLinux/linux/issues/1491Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The existing code doesn't allow setting the number of queues while the
NIC is down.

Update the ethtool handler functions to support setting the number of
queues while the NIC is at down state.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

added support for the redbox supervision frames
as defined in the IEC-62439-3:2018.
Signed-off-by: Andreas Oetken <andreas.oetken@siemens-energy.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
tcp: tcp_stream_alloc_skb() changes

sk_stream_alloc_skb() is only used by TCP.

Rename it to tcp_stream_alloc_skb() and apply small
optimizations.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Aligning @size argument to 4 bytes is not needed.

The header alignment has nothing to do with @size.

It really depends on skb->head alignment and MAX_TCP_HEADER.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Both IPv4 and IPv6 uses same reserve, no need risking
cache line misses to fetch its value.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sk_stream_alloc_skb() is only used by TCP.

Rename it to make this clear, and move its declaration
to include/net/tcp.h
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

neigh_output() reads n->nud_state and hh->hh_len locklessly.

This is fine, but we need to add annotations and document this.

We evaluate skip_cache first to avoid reading these fields
if the cache has to by bypassed.

syzbot report:

BUG: KCSAN: data-race in __neigh_event_send / ip_finish_output2

write to 0xffff88810798a885 of 1 bytes by interrupt on cpu 1:
 __neigh_event_send+0x40d/0xac0 net/core/neighbour.c:1128
 neigh_event_send include/net/neighbour.h:444 [inline]
 neigh_resolve_output+0x104/0x410 net/core/neighbour.c:1476
 neigh_output include/net/neighbour.h:510 [inline]
 ip_finish_output2+0x80a/0xaa0 net/ipv4/ip_output.c:221
 ip_finish_output+0x3b5/0x510 net/ipv4/ip_output.c:309
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:423
 dst_output include/net/dst.h:450 [inline]
 ip_local_out+0x164/0x220 net/ipv4/ip_output.c:126
 __ip_queue_xmit+0x9d3/0xa20 net/ipv4/ip_output.c:525
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x142a/0x1a00 net/ipv4/tcp_output.c:1405
 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4011 [inline]
 tcp_write_wakeup+0x4a9/0x810 net/ipv4/tcp_output.c:4064
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4079
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x394/0x520 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb9/0x180 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x2e/0x1d0 kernel/time/timer.c:1421
 expire_timers+0x135/0x240 kernel/time/timer.c:1466
 __run_timers+0x368/0x430 kernel/time/timer.c:1734
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1747
 __do_softirq+0x12c/0x26e kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x4e/0xa0 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x69/0x80 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x258/0x2e0 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b4/0x760 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1a3/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff88810798a885 of 1 bytes by interrupt on cpu 0:
 neigh_output include/net/neighbour.h:507 [inline]
 ip_finish_output2+0x79a/0xaa0 net/ipv4/ip_output.c:221
 ip_finish_output+0x3b5/0x510 net/ipv4/ip_output.c:309
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:423
 dst_output include/net/dst.h:450 [inline]
 ip_local_out+0x164/0x220 net/ipv4/ip_output.c:126
 __ip_queue_xmit+0x9d3/0xa20 net/ipv4/ip_output.c:525
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x142a/0x1a00 net/ipv4/tcp_output.c:1405
 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4011 [inline]
 tcp_write_wakeup+0x4a9/0x810 net/ipv4/tcp_output.c:4064
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4079
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x394/0x520 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb9/0x180 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x2e/0x1d0 kernel/time/timer.c:1421
 expire_timers+0x135/0x240 kernel/time/timer.c:1466
 __run_timers+0x368/0x430 kernel/time/timer.c:1734
 run_timer_softirq+0x19/0x30 kernel/time/timer.c:1747
 __do_softirq+0x12c/0x26e kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x4e/0xa0 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x69/0x80 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x258/0x2e0 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b4/0x760 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1a3/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 rest_init+0xee/0x100 init/main.c:734
 arch_call_rest_init+0xa/0xb
 start_kernel+0x5e4/0x669 init/main.c:1142
 secondary_startup_64_no_verify+0xb1/0xbb

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: Support multiple RIF MAC prefixes

Currently, mlxsw enforces that all the netdevs used as router interfaces
(RIFs) have the same MAC prefix (e.g., same 38 MSBs in Spectrum-1).
Otherwise, an error is returned to user space with extack. This patchset
relaxes the limitation through the use of RIF MAC profiles.

A RIF MAC profile is a hardware entity that represents a particular MAC
prefix which multiple RIFs can reference. Therefore, the number of
possible MAC prefixes is no longer one, but the number of profiles
supported by the device.

The ability to change the MAC of a particular netdev is useful, for
example, for users who use the netdev to connect to an upstream provider
that performs MAC filtering. Currently, such users are either forced to
negotiate with the provider or change the MAC address of all other
netdevs so that they share the same prefix.

Patchset overview:

Patches #1-#3 are preparations.

Patch #4 adds actual support for RIF MAC profiles.

Patch #5 exposes RIF MAC profiles as a devlink resource, so that user
space has visibility into the maximum number of profiles and current
occupancy. Useful for debugging and testing (next 3 patches).

Patches #6-#8 add both scale and functional tests.

Patch #9 removes tests that validated the previous limitation. It is now
covered by patch #6 for devices that support a single profile.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

After adding the previous patches, the constraint that all the router
interface MAC addresses have the same prefix is no longer relevant.

Remove the test cases that validated that this constraint is honored.
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When all the RIF MAC profiles are in use, test that it is possible to
change the MAC of a netdev (i.e., a RIF) when its MAC profile is not
shared with other RIFs. Test that replacement fails when the MAC profile
is shared.
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Verify that MAC profile changes are indeed applied and that packets are
forwarded with the correct source MAC.

Output example:

$ ./rif_mac_profiles.sh
TEST: h1->h2: new mac profile                                       [ OK ]
TEST: h2->h1: new mac profile                                       [ OK ]
TEST: h1->h2: edit mac profile                                      [ OK ]
TEST: h2->h1: edit mac profile                                      [ OK ]
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Query the maximum number of supported RIF MAC profiles using
devlink-resource and verify that all available MAC profiles can be utilized
and that an error is generated when user space tries to exceed this number.

Output example in Spectrum-2:

$ TESTS='rif_mac_profile' ./resource_scale.sh
TEST: 'rif_mac_profile' 4                                           [ OK ]
TEST: 'rif_mac_profile' overflow 5                                  [ OK ]
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>