The kernel maintains three markers for the MDB dump:

1. The last bridge device from which the MDB was dumped.
2. The last MDB entry from which the MDB was dumped.
3. The last port-group entry that was dumped.

Add test cases for large scale MDB dump to make sure that all the
configured entries are dumped and that the markers are used correctly.

Specifically, create 2 bridges with 32 ports and add 256 MDB entries in
which all the ports are member of. Test that each bridge reports 8192
(256 * 32) permanent entries. Do that with IPv4, IPv6 and L2 MDB
entries.

On my system, MDB dump of the above is contained in about 50 netlink
messages.

Example output:

 # ./bridge_mdb.sh
 [...]
 INFO: # Large scale dump tests
 TEST: IPv4 large scale dump tests                                   [ OK ]
 TEST: IPv6 large scale dump tests                                   [ OK ]
 TEST: L2 large scale dump tests                                     [ OK ]
 [...]
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Future patches are going to move parts of the bridge MDB code to the
common rtnetlink code in preparation for VXLAN MDB support. To
facilitate code sharing between both drivers, move the validation of the
top level attributes in RTM_{NEW,DEL}MDB messages to a policy that will
eventually be moved to the rtnetlink code.

Use 'NLA_NESTED' for 'MDBA_SET_ENTRY_ATTRS' instead of
NLA_POLICY_NESTED() as this attribute is going to be validated using
different policies in the underlying drivers.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The purpose of the sequence generation counter in the netlink callback
is to identify if a multipart dump is consistent or not by calling
nl_dump_check_consistent() whenever a message is generated.

The function is not invoked by the MDB code, rendering the sequence
generation counter assignment pointless. Remove it.

Note that even if the function was invoked, we still could not
accurately determine if the dump is consistent or not, as there is no
sequence generation counter for MDB entries, unlike nexthop objects, for
example.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

'MDB_PG_FLAGS_PERMANENT' and 'MDB_PERMANENT' happen to have the same
value, but the latter is uAPI and cannot change, so use it when dumping
an MDB entry.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Merge tag 'for-net-next-2023-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next

Luiz Augusto von Dentz says:

====================
pull-request: bluetooth-next

 - Add new PID/VID 0489:e0f2 for MT7921
 - Add VID:PID 13d3:3529 for Realtek RTL8821CE
 - Add CIS feature bits to controller information
 - Set Per Platform Antenna Gain(PPAG) for Intel controllers

* tag 'for-net-next-2023-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next:
  Bluetooth: btintel: Set Per Platform Antenna Gain(PPAG)
  Bluetooth: Make sure LE create conn cancel is sent when timeout
  Bluetooth: Free potentially unfreed SCO connection
  Bluetooth: hci_qca: get wakeup status from serdev device handle
  Bluetooth: L2CAP: Fix potential user-after-free
  Bluetooth: MGMT: add CIS feature bits to controller information
  Bluetooth: hci_conn: Refactor hci_bind_bis() since it always succeeds
  Bluetooth: HCI: Replace zero-length arrays with flexible-array members
  Bluetooth: qca: Fix sparse warnings
  Bluetooth: btusb: Add VID:PID 13d3:3529 for Realtek RTL8821CE
  Bluetooth: btusb: Add new PID/VID 0489:e0f2 for MT7921
  Bluetooth: Fix issue with Actions Semi ATS2851 based devices
====================

Link: https://lore.kernel.org/r/20230209234922.3756173-1-luiz.dentz@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

====================
pull-request: bpf-next 2023-02-11

We've added 96 non-merge commits during the last 14 day(s) which contain
a total of 152 files changed, 4884 insertions(+), 962 deletions(-).

There is a minor conflict in drivers/net/ethernet/intel/ice/ice_main.c
between commit 5b246e53 ("ice: split probe into smaller functions")
from the net-next tree and commit 66c0e13a ("drivers: net: turn on
XDP features") from the bpf-next tree. Remove the hunk given ice_cfg_netdev()
is otherwise there a 2nd time, and add XDP features to the existing
ice_cfg_netdev() one:

        [...]
        ice_set_netdev_features(netdev);
        netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
                               NETDEV_XDP_ACT_XSK_ZEROCOPY;
        ice_set_ops(netdev);
        [...]

Stephen's merge conflict mail:
https://lore.kernel.org/bpf/20230207101951.21a114fa@canb.auug.org.au/

The main changes are:

1) Add support for BPF trampoline on s390x which finally allows to remove many
   test cases from the BPF CI's DENYLIST.s390x, from Ilya Leoshkevich.

2) Add multi-buffer XDP support to ice driver, from Maciej Fijalkowski.

3) Add capability to export the XDP features supported by the NIC.
   Along with that, add a XDP compliance test tool,
   from Lorenzo Bianconi & Marek Majtyka.

4) Add __bpf_kfunc tag for marking kernel functions as kfuncs,
   from David Vernet.

5) Add a deep dive documentation about the verifier's register
   liveness tracking algorithm, from Eduard Zingerman.

6) Fix and follow-up cleanups for resolve_btfids to be compiled
   as a host program to avoid cross compile issues,
   from Jiri Olsa & Ian Rogers.

7) Batch of fixes to the BPF selftest for xdp_hw_metadata which resulted
   when testing on different NICs, from Jesper Dangaard Brouer.

8) Fix libbpf to better detect kernel version code on Debian, from Hao Xiang.

9) Extend libbpf to add an option for when the perf buffer should
   wake up, from Jon Doron.

10) Follow-up fix on xdp_metadata selftest to just consume on TX
    completion, from Stanislav Fomichev.

11) Extend the kfuncs.rst document with description on kfunc
    lifecycle & stability expectations, from David Vernet.

12) Fix bpftool prog profile to skip attaching to offline CPUs,
    from Tonghao Zhang.

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

Link: https://lore.kernel.org/r/20230211002037.8489-1-daniel@iogearbox.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Correct spelling problems for Documentation/isdn/ as reported
by codespell.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20230209071400.31476-9-rdunlap@infradead.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Xin Long says:

====================
net: move more duplicate code of ovs and tc conntrack into nf_conntrack_ovs

We've moved some duplicate code into nf_nat_ovs in:

  "net: eliminate the duplicate code in the ct nat functions of ovs and tc"

This patchset addresses more code duplication in the conntrack of ovs
and tc then creates nf_conntrack_ovs for them, and four functions will
be extracted and moved into it:

  nf_ct_handle_fragments()
  nf_ct_skb_network_trim()
  nf_ct_helper()
  nf_ct_add_helper()
====================

Link: https://lore.kernel.org/r/cover.1675810210.git.lucien.xin@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Now handle_fragments() in OVS and TC have the similar code, and
this patch removes the duplicate code by moving the function
to nf_conntrack_ovs.

Note that skb_clear_hash(skb) or skb->ignore_df = 1 should be
done only when defrag returns 0, as it does in other places
in kernel.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch has no functional changes and just moves frag check and
tc_skb_cb update out of handle_fragments, to make it easier to move
the duplicate code from handle_fragments() into nf_conntrack_ovs later.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch has no functional changes and just moves key and ovs_cb update
out of handle_fragments, and skb_clear_hash() and skb->ignore_df change
into handle_fragments(), to make it easier to move the duplicate code
from handle_fragments() into nf_conntrack_ovs later.

Note that it changes to pass info->family to handle_fragments() instead
of key for the packet type check, as info->family is set according to
key->eth.type in ovs_ct_copy_action() when creating the action.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

There are almost the same code in ovs_skb_network_trim() and
tcf_ct_skb_network_trim(), this patch extracts them into a function
nf_ct_skb_network_trim() and moves the function to nf_conntrack_ovs.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Similar to nf_nat_ovs created by Commit ebddb140 ("net: move the
nat function to nf_nat_ovs for ovs and tc"), this patch is to create
nf_conntrack_ovs to get these functions shared by OVS and TC only.

There are nf_ct_helper() and nf_ct_add_helper() from nf_conntrak_helper
in this patch, and will be more in the following patches.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The code assumes that everything that comes after nlmsgerr are nlattrs.
When calculating their size, it does not account for the initial
nlmsghdr. This may lead to accessing uninitialized memory.

Fixes: bbf48c18 ("libbpf: add error reporting in XDP")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com

malloc() and free() may be completely replaced by sanitizers, use
fopen() and fclose() instead.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-7-iii@linux.ibm.com

malloc() and free() may be completely replaced by sanitizers, use
fopen() and fclose() instead.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-6-iii@linux.ibm.com

To get useful results from the Memory Sanitizer, all code running in a
process needs to be instrumented. When building tests with other
sanitizers, it's not strictly necessary, but is also helpful.
So make sure runqslower and libbpf are compiled with SAN_CFLAGS and
linked with SAN_LDFLAGS.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-5-iii@linux.ibm.com

Memory Sanitizer requires passing different options to CFLAGS and
LDFLAGS: besides the mandatory -fsanitize=memory, one needs to pass
header and library paths, and passing -L to a compilation step
triggers -Wunused-command-line-argument. So introduce a separate
variable for linker flags. Use $(SAN_CFLAGS) as a default in order to
avoid complicating the ASan usage.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-4-iii@linux.ibm.com

This makes it possible to add sanitizer flags.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-3-iii@linux.ibm.com

Using HOSTCC="ccache clang" breaks building the tests, since, when it's
forwarded to e.g. bpftool, the child make sees HOSTCC=ccache and
"clang" is considered a target. Fix by quoting it, and also HOSTLD and
HOSTAR for consistency.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230210001210.395194-2-iii@linux.ibm.com

skbuff_head_cache is misnamed (perhaps for historical reasons?)
because it does not hold heads. Head is the buffer which skb->data
points to, and also where shinfo lives. struct sk_buff is a metadata
structure, not the head.

Eric recently added skb_small_head_cache (which allocates actual
head buffers), let that serve as an excuse to finally clean this up :)

Leave the user-space visible name intact, it could possibly be uAPI.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alex Elder says:

====================
net: ipa: prepare for GSI register updtaes

An upcoming series (or two) will convert the definitions of GSI
registers used by IPA so they use the "IPA reg" mechanism to specify
register offsets and their fields.  This will simplify implementing
the fairly large number of changes required in GSI registers to
support more than 32 GSI channels (introduced in IPA v5.0).

A few minor problems and inconsistencies were found, and they're
fixed here.  The last three patches in this series change the
"ipa_reg" code to separate the IPA-specific part (the base virtual
address, basically) from the generic register part, and the now-
generic code is renamed to use just "reg_" or "REG_" as a prefix
rather than "ipa_reg" or "IPA_REG_".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Rename functions related to register fields so they don't appear to
be IPA-specific, and move their definitions into "reg.h":
    ipa_reg_fmask()	-> reg_fmask()
    ipa_reg_bit()	-> reg_bit()
    ipa_reg_field_max()	-> reg_field_max()
    ipa_reg_encode()	-> reg_encode()
    ipa_reg_decode()	-> reg_decode()
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Rename ipa_reg_offset() to be reg_offset() and move its definition
to "reg.h".  Rename ipa_reg_n_offset() to be reg_n_offset() also.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

IPA register definitions have evolved with each new version.  The
changes required to support more than 32 endpoints in IPA v5.0 made
it best to define a unified mechanism for defining registers and
their fields.

GSI register definitions, meanwhile, have remained fairly stable.
And even as the total number of IPA endpoints goes beyond 32, the
number of GSI channels on a given EE that underly endpoints still
remains 32 or less.

Despite that, GSI v3.0 (which is used with IPA v5.0) extends the
number of channels (and events) it supports to be about 256, and as
a result, many GSI register definitions must change significantly.
To address this, we'll use the same "ipa_reg" mechanism to define
the GSI registers.

As a first step in generalizing the "ipa_reg" to also support GSI
registers, isolate the definitions of the "ipa_reg" and "ipa_regs"
structure types (and some supporting macros) into a new header file,
and remove the "ipa_" and "IPA_" from symbol names.

Separate the IPA register ID validity checking from the generic
check that a register ID is in range.  Aside from that, this is
intended to have no functional effect on the code.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move some static inline function definitions out of "gsi_reg.h" and
into "gsi.c", which is the only place they're used.  Rename them so
their names identify the register they're associated with.

Move the gsi_channel_type enumerated type definition below the
offset and field definitions for the CH_C_CNTXT_0 register where
it's used.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are seven GSI interrupt types that can be signaled by a single
GSI IRQ.  These are represented in a bitmask, and the gsi_irq_type_id
enumerated type defines what each bit position represents.

Similarly, the global and general GSI interrupt types each has a set
of conditions it signals, and both types have an enumerated type
that defines which bit that represents each condition.

When used, these enumerated values are passed as an argument to BIT()
in *all* cases.  So clean up the code a little bit by defining the
enumerated type values as one-bit masks rather than bit positions.

Rename gsi_general_id to be gsi_general_irq_id for consistency.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

When checking the validity of an IPA register ID, compare it against
all possible ipa_reg_id values.

Rename the function ipa_reg_id_valid() to be specific about what's
being checked.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Soon IPA v5.0+ will be supported, and when that happens we will be
able to enable support for the SDX65 (IPA v5.0), SM8450 (IPA v5.1),
and SM8550 (IPA v5.5).

Fix the comment about the GSI version used for IPA v3.1.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The reg_addr field in the IPA structure is set but never used.
Get rid of it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Starting at IPA v4.11, the GSI_GENERIC_COMMAND GSI register got a
new PARAMS field.  The code that encodes a value into that field
sets it unconditionally, which is wrong.

We currently only provide 0 as the field's value, so this error has
no real effect.  Still, it's a bug, so let's fix it.

Fix an (unrelated) incorrect comment as well.  Fields in the
ERROR_LOG GSI register actually *are* defined for IPA versions
prior to v3.5.1.

Fixes: fe68c43c ("net: ipa: support enhanced channel flow control")
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add the following TC flower filter keys to lan966x for IS2:
- ipv4_addr (sip and dip)
- ipv6_addr (sip and dip)
- control (IPv4 fragments)
- portnum (tcp and udp port numbers)
- basic (L3 and L4 protocol)
- vlan (outer vlan tag info)
- tcp (tcp flags)
- ip (tos field)

As the parsing of these keys is similar between lan966x and sparx5, move
the code in a separate file to be shared by these 2 chips. And put the
specific parsing outside of the common functions.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

David Howells says:

====================
rxrpc development

Here are some miscellaneous changes for rxrpc:

 (1) Use consume_skb() rather than kfree_skb_reason().

 (2) Fix unnecessary waking when poking and already-poked call.

 (3) Add ack.rwind to the rxrpc_tx_ack tracepoint as this indicates how
     many incoming DATA packets we're telling the peer that we are
     currently willing to accept on this call.

 (4) Reduce duplicate ACK transmission.  We send ACKs to let the peer know
     that we're increasing the receive window (ack.rwind) as we consume
     packets locally.  Normal ACK transmission is triggered in three places
     and that leads to duplicates being sent.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove unused bulk clocks struct from the miic state and use an already
existing miic variable in miic_config().
Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Link: https://lore.kernel.org/r/20230208161249.329631-1-clement.leger@bootlin.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Use string_is_terminated() helper instead of cpecific memchr() call.
This shows better the intention of the call.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230208133153.22528-3-andriy.shevchenko@linux.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Use string_is_terminated() helper instead of cpecific memchr() call.
This shows better the intention of the call.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230208133153.22528-2-andriy.shevchenko@linux.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Move string_is_valid() to the header for wider use.

While at it, rename to string_is_terminated() to be
precise about its semantics.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230208133153.22528-1-andriy.shevchenko@linux.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Add support for cable diagnostics in lan8841 PHY. It has the same
registers layout as lan8814 PHY, therefore reuse the functionality.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230208114406.1666671-1-horatiu.vultur@microchip.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Add IPsec offloading support for NFP3800. Include data
plane and control plane.

Data plane: add IPsec packet process flow in NFP3800
datapath (NFDk).

Control plane: add an algorithm support distinction flow
in xfrm hook function xdo_dev_state_add(), as NFP3800 has
a different set of IPsec algorithm support.

This matches existing support for the NFP6000/NFP4000 and
their NFD3 datapath.

In addition, fixup the md_bytes calculation for NFD3 datapath
to make sure the two datapahts are keept in sync.
Signed-off-by: Huanhuan Wang <huanhuan.wang@corigine.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230208091000.4139974-1-simon.horman@corigine.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Paolo Abeni says:

====================
net: introduce rps_default_mask

Real-time setups try hard to ensure proper isolation between time
critical applications and e.g. network processing performed by the
network stack in softirq and RPS is used to move the softirq
activity away from the isolated core.

If the network configuration is dynamic, with netns and devices
routinely created at run-time, enforcing the correct RPS setting
on each newly created device allowing to transient bad configuration
became complex.

Additionally, when multi-queue devices are involved, configuring rps
in user-space on each queue easily becomes very expensive, e.g.
some setups use veths with per cpu queues.

These series try to address the above, introducing a new
sysctl knob: rps_default_mask. The new sysctl entry allows
configuring a netns-wide RPS mask, to be enforced since receive
queue creation time without any fourther per device configuration
required.

Additionally, a simple self-test is introduced to check the
rps_default_mask behavior.
====================

Link: https://lore.kernel.org/r/cover.1675789134.git.pabeni@redhat.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>