The pcs_rane() method is not called, so lets just remove this
redundant code.
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/E1sCErU-00EOPr-MC@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Remove useless NULL pointer initialisations for "PCS" methods from the
dwxgmac2 code.
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/E1sCErP-00EOPl-IT@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

First of all the flags are never set by any of the driver parts. If nobody
have them set then the respective statements will always have the same
result. Thus the statements can be simplified or even dropped with no risk
to break things.

Secondly shall any of the TBI or RTBI flag is set the MDIO-bus
registration will be bypassed. Why? It really seems weird. It's perfectly
fine to have a TBI/RTBI-capable PHY configured over the MDIO bus
interface.

Based on the notes above the TBI/RTBI PCS flags can be freely dropped thus
simplifying the driver code.
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/E1sCErK-00EOPf-EP@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

There are too many ifdef in IPv6 segment routing code that may cause logic
problems. like commit 160e9d27 ("ipv6: sr: fix invalid unregister error
path"). To avoid this, the init functions are redefined for both cases. The
code could be more clear after all fidefs are removed.
Suggested-by: Simon Horman <horms@kernel.org>
Suggested-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240529040908.3472952-1-liuhangbin@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

A comment in define_trace.h clearly states:

 TRACE_INCLUDE_PATH if the path is something other than core kernel
                                                           vvvvvvvvvvvvvv
 include/trace then this macro can define the path to use. Note, the path
 is relative to define_trace.h, not the file including it. Full path names
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 for out of tree modules must be used.

fjes uses path relative to itself. Which (somehow) works most of
the time. Except when the kernel tree is "nested" in another
kernel tree, and ../drivers/net/fjes actually exists. In which
case build will use the header file from the wrong directory.

I've been trying to figure out why net NIPA builder is constantly
failing for the last 5 days, with:

include/trace/../../../drivers/net/fjes/fjes_trace.h:88:17: error: ‘__assign_str’ undeclared (first use in this function)
   88 |                 __assign_str(err, err);
      |                 ^~~~~~~~~~~~

when the line in the tree clearly has only one "err". NIPA does
indeed have "nested" trees, because it uses git work-trees and
the tree on the "outside" is not very up to date.

Link: https://lore.kernel.org/r/20240529023322.3467755-1-kuba@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Shannon Nelson says:

====================
ionic: updates for v6.11

These are a few minor fixes for the ionic driver to clean
up a some little things that have been waiting for attention.
These were originally sent for net, but now respun for net-next.

v1: https://lore.kernel.org/netdev/20240521013715.12098-1-shannon.nelson@amd.com/
====================

Link: https://lore.kernel.org/r/20240529000259.25775-1-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

All the changes here are whitespace and comments, no code
or definitions changed.  Not all issues were addressed, but
it is much better than it was.  Mostly fixed was a lot
of "Excess union member" and ''rsvd' not described' warnings.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-8-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

We don't want to try to sync more length than might be
in the first frag of an Rx skb, so make sure to use
the frag_len rather than the full len.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-7-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

There is no reason not to use netdev_name() in these places, so do just
as the title states.
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Link: https://lore.kernel.org/r/20240529000259.25775-6-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

As the title states, mark unlikely error paths in the data path as
unlikely.
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-5-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Pass the ionic_txq_desc instead of re-referencing it from the q->txq
array since the caller to ionic_tx_tso_post will always have the
current ionic_txq_desc pointer already.
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-4-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Recovery from broken states can be hard.  If the LIF reset in
the fw_down path didn't work because the PCI link was broken,
the FW won't be in the right state for proper restart.  We can
fire another LIF reset in the fw_up path to be sure things
are clean on restart.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-3-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Address a warning about potential string truncation based on the
string buffer sizes.  We can add some hints to the string format
specifier to set limits on the resulting possible string to
squelch the complaints.
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240529000259.25775-2-shannon.nelson@amd.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Each object file contains information about which module it gets linked
into, so linking the same file into multiple modules now causes a warning:

scripts/Makefile.build:254: drivers/net/ethernet/hisilicon/hns3/Makefile: hns3_common/hclge_comm_cmd.o is added to multiple modules: hclge hclgevf
scripts/Makefile.build:254: drivers/net/ethernet/hisilicon/hns3/Makefile: hns3_common/hclge_comm_rss.o is added to multiple modules: hclge hclgevf
scripts/Makefile.build:254: drivers/net/ethernet/hisilicon/hns3/Makefile: hns3_common/hclge_comm_tqp_stats.o is added to multiple modules: hclge hclgevf

Change the way that hns3 is built by moving the three common files into a
separate module with exported symbols instead.

Fixes: 5f20be4e ("net: hns3: refactor hns3 makefile to support hns3_common module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528161603.2443125-1-arnd@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Each object file contains information about which module it gets linked
into, so linking the same file into multiple modules now causes a warning:

scripts/Makefile.build:254: drivers/net/ethernet/marvell/octeontx2/nic/Makefile: otx2_devlink.o is added to multiple modules: rvu_nicpf rvu_nicvf

Change the way that octeontx2 ethernet is built by moving the common
file into a separate module with exported symbols instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528152527.2148092-1-arnd@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Joe Damato says:

====================
mlx4: Add support for netdev-genl API

There are no functional changes from v5, which I mistakenly sent right
after net-next was closed (oops). This revision, however, includes
Tariq's Reviewed-by tags of the v5 in each commit message. See the
changelog below.

This series adds support to mlx4 for the netdev-genl API which makes it
much easier for users and user programs to map NAPI IDs back to
ifindexes, queues, and IRQs. This is extremely useful for a number of
use cases, including epoll-based busy poll.

In addition, this series includes a patch to generate per-queue
statistics using the netlink API, as well.

To facilitate the stats, patch 1/3 adds a field "alloc_fail" to the ring
structure. This is incremented by the driver in an appropriate place and
used in patch 3/3 as alloc_fail.

Please note: I do not have access to mlx4 hardware, but I've been
working closely with Martin Karsten from University of Waterloo (CC'd)
who has very graciously tested my patches on their mlx4 hardware (hence
his Tested-by attribution in each commit). His latest research work is
particularly interesting [1] and this series helps to support that (and
future) work.

Martin re-test v4 using Jakub's suggested tool [2] and the
stats.pkt_byte_sum and stats.qstat_by_ifindex tests passed. He also
adjusted the queue count and re-ran test to confirm it still passed even
if the queue count was modified.

[1]: https://dl.acm.org/doi/pdf/10.1145/3626780
[2]: https://lore.kernel.org/lkml/20240423175718.4ad4dc5a@kernel.org/
====================

Link: https://lore.kernel.org/r/20240528181139.515070-1-jdamato@fastly.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Make mlx4 compatible with the newly added netlink queue stats API.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528181139.515070-4-jdamato@fastly.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Make mlx4 compatible with the newly added netlink queue GET APIs.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528181139.515070-3-jdamato@fastly.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

mlx4_en_alloc_frags currently returns -ENOMEM when mlx4_alloc_page
fails but does not increment a stat field when this occurs.

A new field called alloc_fail has been added to struct mlx4_en_rx_ring
which is now incremented in mlx4_en_rx_ring when -ENOMEM occurs.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528181139.515070-2-jdamato@fastly.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

MD Danish Anwar says:

====================
Introduce switch mode support for ICSSG driver

This series adds support for switch-mode for ICSSG driver. This series
also introduces helper APIs to configure firmware maintained FDB
(Forwarding Database) and VLAN tables. These APIs are later used by ICSSG
driver in switch mode.

Now the driver will boot by default in dual EMAC mode. When first ICSSG
interface is added to bridge driver will still be in EMAC mode. As soon as
second ICSSG interface is added to same bridge, switch-mode will be
enabled and switch firmwares will be loaded to PRU cores. The driver will
remain in dual EMAC mode if ICSSG interfaces are added to two different
bridges or if two different interfaces (One ICSSG, one other) is added to
the same bridge. We'll only enable is_switch_mode flag when two ICSSG
interfaces are added to same bridge.

We start in dual MAC mode. Let's say lan0 and lan1 are ICSSG interfaces

ip link add name br0 type bridge
ip link set lan0 master br0

At this point, we get a CHANGEUPPER event. Only one port is a member of
the bridge, so we will still be in dual MAC mode.

ip link set lan1 master br0

We get a second CHANGEUPPER event, the second interface lan1 is also ICSSG
interface so we will set the is_switch_mode flag and when interfaces are
brought up again, ICSSG switch firmwares will be loaded to PRU Cores.

There are some other cases to consider as well.

ip link add name br0 type bridge
ip link add name br1 type bridge

ip link set lan0 master br0
ip link set ppp0 master br0

Here we are adding lan0 (ICSSG) and ppp0 (non ICSSG) to same bridge, as
they both are not ICSSG, we will still be running in dual EMAC mode.

ip link set lan1 master br1
ip link set vpn0 master br1

Here we are adding lan1 (ICSSG) and vpn0 (non ICSSG) to same bridge, as
they both are not ICSSG, we will still be running in dual EMAC mode.

This is v6 of the series.

Changes from v5 to v6:
*) Removed __packed from structures in icssg_config.h file.
*) Added RB tags of Andrew Lunn <andrew@lunn.ch> to patch 2/3 and patch
   3/3 of this series.

Changes from v4 to v5:
*) Rebased on 6.10-rc1.
*) Dropped the RFC tag.

Changes from v3 to v4:
*) Added RFC tag as net-next is closed now.
*) Modified the driver to remove the need of bringing interfaces up / down
   for enabling / disabling switch mode. Now switch mode can be enabled
   without bringig interfaces up / down as requested by Andrew Lunn
   <andrew@lunn.ch>
*) Modified commit message of patch 3/3.

Changes from v2 to v3:
*) Dropped RFC tag.
*) Used ether_addr_copy() instead of manually copying mac address using
   for loop in patch 1/3 as suggested by Andrew Lunn <andrew@lunn.ch>
*) Added helper API icssg_fdb_setup() in patch 1/3 to reduce code
   duplication as suggested by Andrew Lunn <andrew@lunn.ch>
*) In prueth_switchdev_stp_state_set() removed BR_STATE_LEARNING as
   learning without forwarding is not supported by ICSSG firmware.
*) Used ether_addr_equal() wherever possible in patch 2/3 as suggested
   by Andrew Lunn <andrew@lunn.ch>
*) Fixed typo "nit: s/prueth_switchdevice_nb/prueth_switchdev_nb/" in
   patch 2/3 as suggested by Simon Horman <horms@kernel.org>
*) Squashed "#include "icssg_mii_rt.h" to patch 2/3 from patch 3/3 as
   suggested by Simon Horman <horms@kernel.org>
*) Rebased on latest net-next/main.

Changes from v1 to v2:
*) Removed TAPRIO support patch from this series.
*) Stopped using devlink for enabling switch-mode as suggested by Andrew L
*) Added read_poll_timeout() in patch 1 / 3 as suggested by Andrew L.

v1 https://lore.kernel.org/all/20230830110847.1219515-4-danishanwar@ti.com/
v2 https://lore.kernel.org/all/20240118071005.1514498-1-danishanwar@ti.com/
v3 https://lore.kernel.org/all/20240327114054.1907278-1-danishanwar@ti.com/
v4 https://lore.kernel.org/all/20240515060320.2783244-1-danishanwar@ti.com/
v5 https://lore.kernel.org/all/20240527052738.152821-1-danishanwar@ti.com/

Thanks and Regards,
Md Danish Anwar
====================

Link: https://lore.kernel.org/r/20240528113734.379422-1-danishanwar@ti.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

Add support for ICSSG switch firmware using existing Dual EMAC driver
with switchdev.

Limitations:
VLAN offloading is limited to 0-256 IDs.
MDB/FDB static entries are limited to 511 entries and different FDBs can
hash to same bucket and thus may not completely offloaded

Example assuming ETH1 and ETH2 as ICSSG2 interfaces:

Switch to ICSSG Switch mode:
 ip link add name br0 type bridge
 ip link set dev eth1 master br0
 ip link set dev eth2 master br0
 ip link set dev br0 up
 bridge vlan add dev br0 vid 1 pvid untagged self

Going back to Dual EMAC mode:

 ip link set dev br0 down
 ip link set dev eth1 nomaster
 ip link set dev eth2 nomaster
 ip link del name br0 type bridge

By default, Dual EMAC firmware is loaded, and can be changed to switch
mode by above steps
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

ICSSG can operating in switch mode with 2 ext port and 1 host port with
VLAN/FDB/MDB and STP offloading. Add switchdev based driver to
support the same.

Driver itself will be integrated with icssg_prueth in future commits
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Introduce helper functions to configure firmware FDB tables, VLAN tables
and Port VLAN ID settings to aid adding Switch mode support.
Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Remove commented out code
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Link: https://lore.kernel.org/r/20240528160036.404946-2-thorsten.blum@toblux.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Convert felix to provide its own phylink MAC operations, thus
avoiding the shim layer in DSA's port.c.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/E1sByYA-00EM0y-Jn@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

No DSA driver makes use of the mac_prepare()/mac_finish() shimmed
operations anymore, so we can remove these.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/E1sByNx-00ELW1-Vp@rmk-PC.armlinux.org.ukSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Donald Hunter says:

====================
doc: netlink: Fixes for ynl doc generator

Several fixes to ynl-gen-rst to resolve issues that can be seen
in:

https://docs.kernel.org/6.10-rc1/networking/netlink_spec/dpll.html#device-id-get
https://docs.kernel.org/6.10-rc1/networking/netlink_spec/dpll.html#lock-status

In patch 2, by not using 'sanitize' for op docs, any formatting in the
.yaml gets passed straight through to the generated .rst which means
that basic rst (also markdown compatible) list formatting can be used in
the .yaml
====================

Link: https://lore.kernel.org/r/20240528140652.9445-1-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The generated .rst has pre and post headings without any values, e.g.
here:

https://docs.kernel.org/6.9/networking/netlink_spec/dpll.html#device-id-get

Emit keys and values in the generated .rst
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240528140652.9445-5-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Generate op flags as an inline list instead of a stringified python
value.
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240528140652.9445-4-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

The doc strings for do/dump ops are emitted as toplevel .rst constructs
so they can be multi-line. Pass multi-line text straight through to the
.rst to retain any simple formatting from the .yaml

This fixes e.g. list formatting for the pin-get docs in dpll.yaml:

https://docs.kernel.org/6.9/networking/netlink_spec/dpll.html#pin-getSigned-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240528140652.9445-3-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Fix the newline replacement in ynl-gen-rst.py to put spaces between
concatenated lines. This fixes the broken doc string formatting.

See the dpll docs for an example of broken concatenation:

https://docs.kernel.org/6.9/networking/netlink_spec/dpll.html#lock-statusSigned-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240528140652.9445-2-donald.hunter@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Alexander Sverdlin says:

====================
net: ethernet: ti: am65-cpsw-nuss: support stacked switches

Currently an external Ethernet switch connected to a am65-cpsw-nuss CPU
port will not be probed successfully because of_find_net_device_by_node()
will not be able to find the netdev of the CPU port.

It's necessary to populate of_node of the struct device for the
am65-cpsw-nuss ports. DT nodes of the ports are already stored in per-port
private data, but because of some legacy reasons the naming ("phy_node")
was misleading.
====================

Link: https://lore.kernel.org/r/20240528075954.3608118-1-alexander.sverdlin@siemens.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

So that of_find_net_device_by_node() can find cpsw-nuss ports and other DSA
switches can be stacked downstream.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20240528075954.3608118-3-alexander.sverdlin@siemens.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Rename phy_node to port_np to better reflect what it actually is,
because the new phylink API takes netdev node (or DSA port node),
and resolves the phandle internally.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20240528075954.3608118-2-alexander.sverdlin@siemens.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Eric Dumazet says:

====================
tcp: fix tcp_poll() races

Flakes in packetdrill tests stressing epoll_wait()
were root caused to bad ordering in tcp_write_err()

Precisely, we have to call sk_error_report() after
tcp_done().

When fixing this issue, we discovered tcp_abort(),
tcp_v4_err() and tcp_v6_err() had similar issues.

Since tcp_reset() has the correct ordering,
first patch takes part of it and creates
tcp_done_with_error() helper.
====================

Link: https://lore.kernel.org/r/20240528125253.1966136-1-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

These functions have races when they:

1) Write sk->sk_err
2) call sk_error_report(sk)
3) call tcp_done(sk)

As described in prior patches in this series:

An smp_wmb() is missing.
We should call tcp_done() before sk_error_report(sk)
to have consistent tcp_poll() results on SMP hosts.

Use tcp_done_with_error() where we centralized the
correct sequence.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-5-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tcp_abort() has the same issue than the one fixed in the prior patch
in tcp_write_err().

In order to get consistent results from tcp_poll(), we must call
sk_error_report() after tcp_done().

We can use tcp_done_with_error() to centralize this logic.

Fixes: c1e64e29 ("net: diag: Support destroying TCP sockets.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-4-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

I noticed flakes in a packetdrill test, expecting an epoll_wait()
to return EPOLLERR | EPOLLHUP on a failed connect() attempt,
after multiple SYN retransmits. It sometimes return EPOLLERR only.

The issue is that tcp_write_err():
 1) writes an error in sk->sk_err,
 2) calls sk_error_report(),
 3) then calls tcp_done().

tcp_done() is writing SHUTDOWN_MASK into sk->sk_shutdown,
among other things.

Problem is that the awaken user thread (from 2) sk_error_report())
might call tcp_poll() before tcp_done() has written sk->sk_shutdown.

tcp_poll() only sees a non zero sk->sk_err and returns EPOLLERR.

This patch fixes the issue by making sure to call sk_error_report()
after tcp_done().

tcp_write_err() also lacks an smp_wmb().

We can reuse tcp_done_with_error() to factor out the details,
as Neal suggested.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-3-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tcp_reset() ends with a sequence that is carefuly ordered.

We need to fix [e]poll bugs in the following patches,
it makes sense to use a common helper.
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-2-edumazet@google.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

If a user provides an invalid netconsole configuration during boot time
(e.g., specifying an invalid ethX interface), netconsole will be
entirely disabled. Consequently, the user won't be able to create new
entries in /sys/kernel/config/netconsole/ as that directory does not
exist.

Apart from misconfiguration, another issue arises when ethX is loaded as
a module and the netconsole= line in the command line points to ethX,
resulting in an obvious failure. This renders netconsole unusable, as
/sys/kernel/config/netconsole/ will never appear. This is more annoying
since users reconfigure (or just toggle) the configuratin later (see
commit 5fbd6cdb ("netconsole: Attach cmdline target to dynamic
target"))

Create /sys/kernel/config/netconsole/ even if the command line arguments
are invalid, so, users can create dynamic entries in netconsole.
Reported-by: Aijay Adams <aijay@meta.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20240528084225.3215853-1-leitao@debian.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>