As CAN skbs don't use IP checksums the skb->csum_start variable was used to
store the can-gw CAN frame time-to-live counter together with
skb->ip_summed set to CHECKSUM_UNNECESSARY.
Remove the 'hack' using the skb->csum_start variable and move the content
to can_skb_ext::can_gw_hops of the CAN skb extensions.
The module parameter 'max_hops' has been reduced to a single byte to fit
can_skb_ext::can_gw_hops as the maximum value to be stored is 6.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-6-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This patch removes struct can_skb_priv which was stored at skb->head and
the can_skb_reserve() helper which was used to shift skb->head.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-5-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When routing CAN frames over different CAN interfaces the interface index
skb->iif is overwritten with every single hop. To prevent sending a CAN
frame back to its originating (first) incoming CAN interface another
ifindex variable is needed, which was stored in can_skb_priv::ifindex.
Move the can_skb_priv::ifindex content to can_skb_ext::can_iif.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-3-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
To remove the private CAN bus skb headroom infrastructure 8 bytes need to
be stored in the skb. The skb extensions are a common pattern and an easy
and efficient way to hold private data travelling along with the skb. We
only need the skb_ext_add() and skb_ext_find() functions to allocate and
access CAN specific content as the skb helpers to copy/clone/free skbs
automatically take care of skb extensions and their final removal.
This patch introduces the complete CAN skb extensions infrastructure:
- add struct can_skb_ext in new file include/net/can.h
- add include/net/can.h in MAINTAINERS
- add SKB_EXT_CAN to skbuff.c and skbuff.h
- select SKB_EXTENSIONS in Kconfig when CONFIG_CAN is enabled
- check for existing CAN skb extensions in can_rcv() in af_can.c
- add CAN skb extensions allocation at every skb_alloc() location
- duplicate the skb extensions if cloning outgoing skbs (framelen/gw_hops)
- introduce can_skb_ext_add() and can_skb_ext_find() helpers
The patch also corrects an indention issue in the original code from 2018:
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202602010426.PnGrYAk3-lkp@intel.com/
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-2-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The can_skb_priv::skbcnt variable is used to identify CAN skbs in the RX
path analogue to the skb->hash.
As the skb hash is not filled in CAN skbs move the private skbcnt value to
skb->hash and set skb->sw_hash accordingly. The skb->hash is a value used
for RPS to identify skbs. Use it as intended.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-1-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Even though a peer may have already received a
non-zero value for "RDS_EXTHDR_NPATHS" from a node in the past,
the current peer may not.
Therefore it is important to initiate another rds_send_ping()
after a re-connect to any peer:
It is unknown at that time if we're still talking to the same
instance of RDS kernel modules on the other side.
Otherwise, the peer may just operate on a single lane
("c_npaths == 0"), not knowing that more lanes are available.
However, if "c_with_sport_idx" is supported,
we also need to check that the connection we accepted on lane#0
meets the proper source port modulo requirement, as we fan out:
Since the exchange of "RDS_EXTHDR_NPATHS" and "RDS_EXTHDR_SPORT_IDX"
is asynchronous, initially we have no choice but to accept an incoming
connection (via "accept") in the first slot ("cp_index == 0")
for backwards compatibility.
But that very connection may have come from a different lane
with "cp_index != 0", since the peer thought that we already understood
and handled "c_with_sport_idx" properly, as indicated by a previous
exchange before a module was reloaded.
In short:
If a module gets reloaded, we recover from that, but do *not*
allow a downgrade to support fewer lanes.
Downgrades would require us to merge messages from separate lanes,
which is rather tricky with the current RDS design.
Each lane has its own sequence number space and all messages
would need to be re-sequenced as we merge, all while
handling "RDS_FLAG_RETRANSMITTED" and "cp_retrans" properly.
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-9-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Instead of just blocking the sender until "c_npaths" is known
(it gets updated upon the receipt of a MPRDS PONG message),
simply use the first lane (cp_index#0).
But just using the first lane isn't enough.
As soon as we enqueue messages on a different lane, we'd run the risk
of out-of-order delivery of RDS messages.
Earlier messages enqueued on "cp_index == 0" could be delivered later
than more recent messages enqueued on "cp_index > 0", mostly because of
possible head of line blocking issues causing the first lane to be
slower.
To avoid that, we simply take a snapshot of "cp_next_tx_seq" at the
time we're about to fan-out to more lanes.
Then we delay the transmission of messages enqueued on other lanes
with "cp_index > 0" until cp_index#0 caught up with the delivery of
new messages (from "cp_send_queue") as well as in-flight
messages (from "cp_retrans") that haven't been acknowledged yet
by the receiver.
We also add a new counter "mprds_catchup_tx0_retries" to keep track
of how many times "rds_send_xmit" had to suspend activities,
because it was waiting for the first lane to catch up.
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-8-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Quick clean up to avoid checkpatch errors when adding members to
this struct (Prefer kernel type 'u64' over 'uint64_t').
No functional changes added.
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-7-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When canceling the reconnect worker, care must be taken to reset the
reconnect-pending bit. If the reconnect worker has not yet been
scheduled before it is canceled, the reconnect-pending bit will stay
on forever.
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-6-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In cases where the server (the node with the higher IP-address)
in an RDS/TCP connection is overwhelmed it is possible that the
socket that was just accepted is chock-full of messages, up to
the limit of what the socket receive buffer permits.
Subsequently, "rds_tcp_data_ready" won't be called anymore,
because there is no more space to receive additional messages.
Nor was it called prior to the point of calling "rds_tcp_set_callbacks",
because the "sk_data_ready" pointer didn't even point to
"rds_tcp_data_ready" yet.
We fix this by simply kick-starting the receive-worker
for all cases where the socket state is neither
"TCP_CLOSE_WAIT" nor "TCP_CLOSE".
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-5-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RDS/TCP differs from RDS/RDMA in that message acknowledgment
is done based on TCP sequence numbers:
As soon as the last byte of a message has been acknowledged by the
TCP stack of a peer, rds_tcp_write_space() goes on to discard
prior messages from the send queue.
Which is fine, for as long as the receiver never throws any messages
away.
The dequeuing of messages in RDS/TCP is done either from the
"sk_data_ready" callback pointing to rds_tcp_data_ready()
(the most common case), or from the receive worker pointing
to rds_tcp_recv_path() which is called for as long as the
connection is "RDS_CONN_UP".
However, as soon as rds_conn_path_drop() is called for whatever reason,
including "DR_USER_RESET", "cp_state" transitions to "RDS_CONN_ERROR",
and rds_tcp_restore_callbacks() ends up restoring the callbacks
and thereby disabling message receipt.
So messages already acknowledged to the sender were dropped.
Furthermore, the "->shutdown" callback was always called
with an invalid parameter ("RCV_SHUTDOWN | SEND_SHUTDOWN == 3"),
instead of the correct pre-increment value ("SHUT_RDWR == 2").
inet_shutdown() returns "-EINVAL" in such cases, rendering
this call a NOOP.
So we change rds_tcp_conn_path_shutdown() to do the proper
"->shutdown(SHUT_WR)" call in order to signal EOF to the peer
and make it transition to "TCP_CLOSE_WAIT" (RFC 793).
This should make the peer also enter rds_tcp_conn_path_shutdown()
and do the same.
This allows us to dequeue all messages already received
and acknowledged to the peer.
We do so, until we know that the receive queue no longer has data
(skb_queue_empty()) and that we couldn't have any data
in flight anymore, because the socket transitioned to
any of the states "CLOSING", "TIME_WAIT", "CLOSE_WAIT",
"LAST_ACK", or "CLOSE" (RFC 793).
However, if we do just that, we suddenly see duplicate RDS
messages being delivered to the application.
So what gives?
Turns out that with MPRDS and its multitude of backend connections,
retransmitted messages ("RDS_FLAG_RETRANSMITTED") can outrace
the dequeuing of their original counterparts.
And the duplicate check implemented in rds_recv_local() only
discards duplicates if flag "RDS_FLAG_RETRANSMITTED" is set.
Rather curious, because a duplicate is a duplicate; it shouldn't
matter which copy is looked at and delivered first.
To avoid this entire situation, we simply make the sender discard
messages from the send-queue right from within
rds_tcp_conn_path_shutdown(). Just like rds_tcp_write_space() would
have done, were it called in time or still called.
This makes sure that we no longer have messages that we know
the receiver already dequeued sitting in our send-queue,
and therefore avoid the entire "RDS_FLAG_RETRANSMITTED" fiasco.
Now we got rid of the duplicate RDS message delivery, but we
still run into cases where RDS messages are dropped.
This time it is due to the delayed setting of the socket-callbacks
in rds_tcp_accept_one() via either rds_tcp_reset_callbacks()
or rds_tcp_set_callbacks().
By the time rds_tcp_accept_one() gets there, the socket
may already have transitioned into state "TCP_CLOSE_WAIT",
but rds_tcp_state_change() was never called.
Subsequently, "->shutdown(SHUT_WR)" did not happen either.
So the peer ends up getting stuck in state "TCP_FIN_WAIT2".
We fix that by checking for states "TCP_CLOSE_WAIT", "TCP_LAST_ACK",
or "TCP_CLOSE" and drop the freshly accepted socket in that case.
This problem is observable by running "rds-stress --reset"
frequently on either of the two sides of a RDS connection,
or both while other "rds-stress" processes are exchanging data.
Those "rds-stress" processes reported out-of-sequence
errors, with the expected sequence number being smaller
than the one actually received (due to the dropped messages).
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-4-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Upon "sendmsg", RDS/TCP selects a backend connection based
on a hash calculated from the source-port ("RDS_MPATH_HASH").
However, "rds_tcp_accept_one" accepts connections
in the order they arrive, which is non-deterministic.
Therefore the mapping of the sender's "cp->cp_index"
to that of the receiver changes if the backend
connections are dropped and reconnected.
However, connection state that's preserved across reconnects
(e.g. "cp_next_rx_seq") relies on that sender<->receiver
mapping to never change.
So we make sure that client and server of the TCP connection
have the exact same "cp->cp_index" across reconnects by
encoding "cp->cp_index" in the lower three bits of the
client's TCP source port.
A new extension "RDS_EXTHDR_SPORT_IDX" is introduced,
that allows the server to tell the difference between
clients that do the "cp->cp_index" encoding, and
legacy clients that pick source ports randomly.
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-3-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Introduce a new extension header type RDSV3_EXTHDR_RDMA_BYTES for
an RDMA initiator to exchange rdma byte counts to its target.
Currently, RDMA operations cannot precisely account how many bytes a
peer just transferred via RDMA, which limits per-connection statistics
and future policy (e.g., monitoring or rate/cgroup accounting of RDMA
traffic).
In this patch we expand rds_message_add_extension to accept multiple
extensions, and add new flag to RDS header: RDS_FLAG_EXTHDR_EXTENSION,
along with a new extension to RDS header: rds_ext_header_rdma_bytes.
Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Link: https://patch.msgid.link/20260203055723.1085751-2-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
After 076433bd78 ("net_sched: sch_fq: add fast path
for mostly idle qdisc") we need to remove one unlikely()
because q->internal holds all the fast path packets.
skb = fq_peek(&q->internal);
if (unlikely(skb)) {
q->internal.qlen--;
Calling INET_ECN_set_ce() is very unlikely.
These changes allow fq_dequeue_skb() to be (auto)inlined,
thus making fq_dequeue() faster.
$ scripts/bloat-o-meter -t vmlinux.0 vmlinux
add/remove: 2/2 grow/shrink: 0/1 up/down: 283/-269 (14)
Function old new delta
INET_ECN_set_ce - 267 +267
__pfx_INET_ECN_set_ce - 16 +16
__pfx_fq_dequeue_skb 16 - -16
fq_dequeue_skb 103 - -103
fq_dequeue 1685 1535 -150
Total: Before=24886569, After=24886583, chg +0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260203214716.880853-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix numerous (many) kernel-doc warnings in iucv.[ch]:
- convert function documentation comments to a common (kernel-doc) look,
even for static functions (without "/**")
- use matching parameter and parameter description names
- use better wording in function descriptions (Jakub & AI)
- remove duplicate kernel-doc comments from the header file (Jakub)
Examples:
Warning: include/net/iucv/iucv.h:210 missing initial short description
on line: * iucv_unregister
Warning: include/net/iucv/iucv.h:216 function parameter 'handle' not
described in 'iucv_unregister'
Warning: include/net/iucv/iucv.h:467 function parameter 'answer' not
described in 'iucv_message_send2way'
Warning: net/iucv/iucv.c:727 missing initial short description on line:
* iucv_cleanup_queue
Build-tested with both "make htmldocs" and "make ARCH=s390 defconfig all".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20260203075248.1177869-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tcp_rbtree_insert() is primarily used from tcp_output.c
In tcp_input.c, only (slow path) tcp_collapse() uses it.
Move it to tcp_output.c to allow its (auto)inlining to improve
TCP tx fast path.
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/0 grow/shrink: 4/1 up/down: 445/-115 (330)
Function old new delta
tcp_connect 4277 4478 +201
tcp_event_new_data_sent 162 248 +86
tcp_send_synack 780 862 +82
tcp_fragment 1185 1261 +76
tcp_collapse 1524 1409 -115
Total: Before=24896043, After=24896373, chg +0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260203045110.3499713-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We trust MAX_TCP_HEADER to be large enough.
Using the inlined version of skb_push() trades 8 bytes
of text for better performance of TCP TX fast path.
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/0 grow/shrink: 1/0 up/down: 8/0 (8)
Function old new delta
__tcp_transmit_skb 3181 3189 +8
Total: Before=24896035, After=24896043, chg +0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260203044226.3489941-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
- ath drivers: small features/cleanups
- rtw drivers: mostly refactoring for rtw89 RTL8922DE support
- mac80211: use hrtimers for CAC to avoid too long delays
- cfg80211/mac80211: some initial UHR (Wi-Fi 8) support
-----BEGIN PGP SIGNATURE-----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=/NUu
-----END PGP SIGNATURE-----
Merge tag 'wireless-next-2026-02-04' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next
Johannes Berg says:
====================
Some more changes, including pulls from drivers:
- ath drivers: small features/cleanups
- rtw drivers: mostly refactoring for rtw89 RTL8922DE support
- mac80211: use hrtimers for CAC to avoid too long delays
- cfg80211/mac80211: some initial UHR (Wi-Fi 8) support
* tag 'wireless-next-2026-02-04' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next: (59 commits)
wifi: brcmsmac: phy: Remove unreachable error handling code
wifi: mac80211: Add eMLSR/eMLMR action frame parsing support
wifi: mac80211: add initial UHR support
wifi: cfg80211: add initial UHR support
wifi: ieee80211: add some initial UHR definitions
wifi: mac80211: use wiphy_hrtimer_work for CAC timeout
wifi: mac80211: correct ieee80211-{s1g/eht}.h include guard comments
wifi: ath12k: clear stale link mapping of ahvif->links_map
wifi: ath12k: Add support TX hardware queue stats
wifi: ath12k: Add support RX PDEV stats
wifi: ath12k: Fix index decrement when array_len is zero
wifi: ath12k: support OBSS PD configuration for AP mode
wifi: ath12k: add WMI support for spatial reuse parameter configuration
dt-bindings: net: wireless: ath11k-pci: deprecate 'firmware-name' property
wifi: ath11k: add usecase firmware handling based on device compatible
wifi: ath10k: sdio: add missing lock protection in ath10k_sdio_fw_crashed_dump()
wifi: ath10k: fix lock protection in ath10k_wmi_event_peer_sta_ps_state_chg()
wifi: ath10k: snoc: support powering on the device via pwrseq
wifi: rtw89: pci: warn if SPS OCP happens for RTL8922DE
wifi: rtw89: pci: restore LDO setting after device resume
...
====================
Link: https://patch.msgid.link/20260204121143.181112-3-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There are two:
min_t(int, xxx, mptcp_wnd_end(msk) - msk->snd_nxt);
Both mptcp_wnd_end(msk) and msk->snd_nxt are u64, their difference
(aka the window size) might be limited to 32 bits - but that isn't
knowable from this code.
So checks being added to min_t() detect the potential discard of
significant bits.
Provided the 'avail_size' and return of mptcp_check_allowed_size()
are changed to an unsigned type (size_t matches the type the caller
uses) both min_t() can be changed to min().
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
[ wrapped too long lines when declaring mptcp_check_allowed_size() ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-6-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The MPTCP Netlink specs describe the 'flags' as a u32 type. Internally,
a u8 type was used.
Using a u8 is currently fine, because only the 5 first bits are used.
But there is also no reason not to be aligns with the specs, and
to stick to a u8. Especially because there is a whole of 3 bytes after
in both mptcp_pm_local and mptcp_pm_addr_entry structures.
Also, setting it to a u32 will allow future flags, just in case.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-5-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Similar to tcp, provide a new tracepoint to better understand
mptcp_rcv_space_adjust() behavior, which presents many artifacts.
Note that the used format string is so long that I preferred
wrap it, contrary to guidance for quoted strings.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-4-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
MPTCP uses several calls of the mptcp_rcv_space_init() helper to
initialize the receive space, with a catch-up call in
mptcp_rcv_space_adjust().
Drop all the other strictly not needed invocations and move constant
fields initialization at socket init/reset time.
This removes a bit of complexity from mptcp DRS code. No functional
changes intended.
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-3-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
MPTCP initialize the receive buffer stamp in mptcp_rcv_space_init(),
using the provided subflow stamp. Such helper is invoked in several
places; for passive sockets, space init happened at clone time.
In such scenario, MPTCP ends-up accesses the subflow stamp before
its initialization, leading to quite randomic timing for the first
receive buffer auto-tune event, as the timestamp for newly created
subflow is not refreshed there.
Fix the issue moving the stamp initialization out of the mentioned helper,
at the data transfer start, and always using a fresh timestamp.
Fixes: 013e3179db ("mptcp: fix rcv space initialization")
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-2-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
MPTCP-level OoOs are physiological when multiple subflows are active
concurrently and will not cause retransmissions nor are caused by
drops.
Accounting for them in mptcp_rcvbuf_grow() causes the rcvbuf slowly
drifting towards tcp_rmem[2].
Remove such accounting. Note that subflows will still account for TCP-level
OoO when the MPTCP-level rcvbuf is propagated.
This also closes a subtle and very unlikely race condition with rcvspace
init; active sockets with user-space holding the msk-level socket lock,
could complete such initialization in the receive callback, after that the
first OoO data reaches the rcvbuf and potentially triggering a divide by
zero Oops.
Fixes: e118cdc34d ("mptcp: rcvbuf auto-tuning improvement")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260203-net-next-mptcp-misc-feat-6-20-v1-1-31ec8bfc56d1@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The gcc-16.0.1 snapshot produces a false-positive warning that turns
into a build failure with CONFIG_WERROR:
In file included from arch/x86/include/asm/string.h:6,
from net/vmw_vsock/vmci_transport.c:10:
In function 'vmci_transport_packet_init',
inlined from '__vmci_transport_send_control_pkt.constprop' at net/vmw_vsock/vmci_transport.c:198:2:
arch/x86/include/asm/string_32.h:150:25: error: argument 2 null where non-null expected because argument 3 is nonzero [-Werror=nonnull]
150 | #define memcpy(t, f, n) __builtin_memcpy(t, f, n)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
net/vmw_vsock/vmci_transport.c:164:17: note: in expansion of macro 'memcpy'
164 | memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
| ^~~~~~
arch/x86/include/asm/string_32.h:150:25: note: in a call to built-in function '__builtin_memcpy'
net/vmw_vsock/vmci_transport.c:164:17: note: in expansion of macro 'memcpy'
164 | memcpy(&pkt->u.wait, wait, sizeof(pkt->u.wait));
| ^~~~~~
This seems relatively harmless, and it so far the only instance of this
warning I have found. The __vmci_transport_send_control_pkt function
is called either with wait=NULL or with one of the type values that
pass 'wait' into memcpy() here, but not from the same caller.
Replacing the memcpy with a struct assignment is otherwise the same
but avoids the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Bryan Tan <bryan-bt.tan@broadcom.com>
Link: https://patch.msgid.link/20260203163406.2636463-1-arnd@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Replace sprintf with sysfs_emit in sysfs show() methods as outlined in
Documentation/filesystems/sysfs.rst.
sysfs_emit is preferred to sprintf in sysfs show() methods as it is safer
with buffer handling.
Signed-off-by: David Corvaglia <david@corvaglia.dev>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/0100019c1fc2bcc3-bc9ca2f1-22d7-4250-8441-91e4af57117b-000000@email.amazonses.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add 2-bit tcpi_ecn_mode feild within tcp_info to indicate which ECN
mode is negotiated: ECN_MODE_DISABLED, ECN_MODE_RFC3168, ECN_MODE_ACCECN,
or ECN_MODE_PENDING. This is done by utilizing available bits from
tcpi_accecn_opt_seen (reduced from 16 bits to 2 bits) and
tcpi_accecn_fail_mode (reduced from 16 bits to 4 bits).
Also, an extra 24-bit tcpi_options2 field is identified to represent
newer options and connection features, as all 8 bits of tcpi_options
field have been used.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Co-developed-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-14-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Detect spurious retransmission of a previously sent ACK carrying the
AccECN option after the second retransmission. Since this might be caused
by the middlebox dropping ACK with options it does not recognize, disable
the sending of the AccECN option in all subsequent ACKs. This patch
follows Section 3.2.3.2.2 of AccECN spec (RFC9768), and a new field
(accecn_opt_sent_w_dsack) is added to indicate that an AccECN option was
sent with duplicate SACK info.
Also, a new AccECN option sending mode is added to tcp_ecn_option sysctl:
(TCP_ECN_OPTION_PERSIST), which ignores the AccECN fallback policy and
persistently sends AccECN option once it fits into TCP option space.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-13-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Based on specification:
https://tools.ietf.org/id/draft-ietf-tcpm-accurate-ecn-28.txt
Based on Section 3.1.5 of AccECN spec (RFC9768), a TCP Server in
AccECN mode MUST NOT set ECT on any packet for the rest of the connection,
if it has received or sent at least one valid SYN or Acceptable SYN/ACK
with (AE,CWR,ECE) = (0,0,0) during the handshake.
In addition, a host in AccECN mode that is feeding back the IP-ECN
field on a SYN or SYN/ACK MUST feed back the IP-ECN field on the
latest valid SYN or acceptable SYN/ACK to arrive.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-11-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
For Accurate ECN, the first SYN/ACK sent by the TCP server shall set
the ACE flag (Table 1 of RFC9768) and the AccECN option to complete the
capability negotiation. However, if the TCP server needs to retransmit
such a SYN/ACK (for example, because it did not receive an ACK
acknowledging its SYN/ACK, or received a second SYN requesting AccECN
support), the TCP server retransmits the SYN/ACK without the AccECN
option. This is because the SYN/ACK may be lost due to congestion, or a
middlebox may block the AccECN option. Furthermore, if this retransmission
also times out, to expedite connection establishment, the TCP server
should retransmit the SYN/ACK with (AE,CWR,ECE) = (0,0,0) and without the
AccECN option, while maintaining AccECN feedback mode.
This complies with Section 3.2.3.2.2 of the AccECN spec RFC9768.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-10-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Before this patch, retransmitted SYN/ACK did not have a specific
synack_type; however, the upcoming patch needs to distinguish between
retransmitted and non-retransmitted SYN/ACK for AccECN negotiation to
transmit the fallback SYN/ACK during AccECN negotiation. Therefore, this
patch introduces a new synack_type (TCP_SYNACK_RETRANS).
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-9-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Based on AccECN spec (RFC9768) Section 3.1.4.1, if the sender of an
AccECN SYN (the TCP Client) times out before receiving the SYN/ACK, it
SHOULD attempt to negotiate the use of AccECN at least one more time
by continuing to set all three TCP ECN flags (AE,CWR,ECE) = (1,1,1) on
the first retransmitted SYN (using the usual retransmission time-outs).
If this first retransmission also fails to be acknowledged, in
deployment scenarios where AccECN path traversal might be problematic,
the TCP Client SHOULD send subsequent retransmissions of the SYN with
the three TCP-ECN flags cleared (AE,CWR,ECE) = (0,0,0).
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-8-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When AccECN is not successfully negociated for a TCP flow, it defaults
fallback to classic ECN (RFC3168). However, L4S service will fallback
to non-ECN.
This patch enables congestion control module to control whether it
should not fallback to classic ECN after unsuccessful AccECN negotiation.
A new CA module flag (TCP_CONG_NO_FALLBACK_RFC3168) identifies this
behavior expected by the CA.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-6-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Two flags for congestion control (CC) module are added in this patch
related to AccECN negotiation. First, a new flag (TCP_CONG_NEEDS_ACCECN)
defines that the CC expects to negotiate AccECN functionality using the
ECE, CWR and AE flags in the TCP header.
Second, during ECN negotiation, ECT(0) in the IP header is used. This
patch enables CC to control whether ECT(0) or ECT(1) should be used on
a per-segment basis. A new flag (TCP_CONG_ECT_1_NEGOTIATION) defines the
expected ECT value in the IP header by the CA when not-yet initialized
for the connection.
The detailed AccECN negotiaotn can be found in IETF RFC9768.
Co-developed-by: Olivier Tilmans <olivier.tilmans@nokia.com>
Signed-off-by: Olivier Tilmans <olivier.tilmans@nokia.com>
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-5-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
As AccECN may keep CWR bit asserted due to different
interpretation of the bit, flushing with GRO because of
CWR may effectively disable GRO until AccECN counter
field changes such that CWR-bit becomes 0.
There is no harm done from not immediately forwarding the
CWR'ed segment with RFC3168 ECN.
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-3-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add newly acked pkts EWMA. When ACK thinning occurs, select
between safer and unsafe cep delta in AccECN processing based
on it. If the packets ACKed per ACK tends to be large, don't
conservatively assume ACE field overflow.
This patch uses the existing 2-byte holes in the rx group for new
u16 variables withtout creating more holes. Below are the pahole
outcomes before and after this patch:
[BEFORE THIS PATCH]
struct tcp_sock {
[...]
u32 delivered_ecn_bytes[3]; /* 2744 12 */
/* XXX 4 bytes hole, try to pack */
[...]
__cacheline_group_end__tcp_sock_write_rx[0]; /* 2816 0 */
[...]
/* size: 3264, cachelines: 51, members: 177 */
}
[AFTER THIS PATCH]
struct tcp_sock {
[...]
u32 delivered_ecn_bytes[3]; /* 2744 12 */
u16 pkts_acked_ewma; /* 2756 2 */
/* XXX 2 bytes hole, try to pack */
[...]
__cacheline_group_end__tcp_sock_write_rx[0]; /* 2816 0 */
[...]
/* size: 3264, cachelines: 51, members: 178 */
}
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Co-developed-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260131222515.8485-2-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Required by DCB/QoS support of the switch driver, since the rx packets
will have non-zero priorities.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260131021854.3405036-3-mmyangfl@gmail.com
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Packet priority is part of the tag, and the priority and code fields are
used by tx and rx. Make revisions to reflect the facts.
Signed-off-by: David Yang <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260131021854.3405036-2-mmyangfl@gmail.com
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
devlink_rate_nodes_check() was used to verify there are no devlink rate
nodes created when switching the esw mode.
Rate management code is about to become more complex, so refactor this
function:
- remove unused param 'mode'.
- add a new 'rate_filter' param.
- rename to devlink_rates_check().
- expose devlink_rate_is_node() to be used as a rate filter.
This makes it more usable from multiple places, so use it from those
places as well.
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20260128112544.1661250-6-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit [1] defined the locking expectations for nested devlink
instances: the nested-in devlink instance lock needs to be acquired
before the nested devlink instance lock. The code handling devlink rels
was architected with that assumption in mind.
There are no actual users of double locking yet but that is about to
change in the upcoming patches in the series.
Code operating on nested devlink instances will require also obtaining
the nested-in instance lock, but such code may already be called from a
variety of places with the nested devlink instance lock. Then, there's
no way to acquire the nested-in lock other than making sure that all
callers acquire it first.
Reversing the nested lock order allows incrementally acquiring the
nested-in instance lock when needed (perhaps even a chain of locks up to
the root) without affecting any caller.
The only affected use of nesting is devlink_nl_nested_fill(), which
iterates over nested devlink instances with the RCU lock, without
locking them, so there's no possibility of deadlock.
So this commit just updates a comment regarding the nested locks.
[1] commit c137743bce ("devlink: introduce object and nested devlink
relationship infra")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20260128112544.1661250-4-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch implements .splice_read interface of mptcp struct proto_ops
as mptcp_splice_read() with reference to tcp_splice_read().
Corresponding to __tcp_splice_read(), __mptcp_splice_read() is defined,
invoking mptcp_read_sock() instead of tcp_read_sock().
mptcp_splice_read() is almost the same as tcp_splice_read(), except for
sock_rps_record_flow().
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260130-net-next-mptcp-splice-v2-4-31332ba70d7f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Export struct tcp_splice_state and tcp_splice_data_recv() in net/tcp.h
so that they can be used by MPTCP in the next patch.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Acked-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260130-net-next-mptcp-splice-v2-3-31332ba70d7f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Current in-kernel TCP sockets -- i.e. from nvme_tcp_try_recv() -- need
to call .read_sock interface of struct proto_ops, but it's not
implemented in MPTCP.
This patch implements it with reference to __tcp_read_sock() and
__mptcp_recvmsg_mskq().
Corresponding to tcp_recv_skb(), a new helper for MPTCP named
mptcp_recv_skb() is added to peek a skb from sk->sk_receive_queue.
Compared with __mptcp_recvmsg_mskq(), mptcp_read_sock() uses
sk->sk_rcvbuf as the max read length. The LISTEN status is checked
before the while loop, and mptcp_recv_skb() and mptcp_cleanup_rbuf()
are invoked after the loop. In the loop, all flags checks for
__mptcp_recvmsg_mskq() are removed.
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260130-net-next-mptcp-splice-v2-2-31332ba70d7f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch extracts the free skb related code in __mptcp_recvmsg_mskq()
into a new helper mptcp_eat_recv_skb().
This new helper will be used in the next patch.
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260130-net-next-mptcp-splice-v2-1-31332ba70d7f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
All inet6_cork users also use one inet_cork_full.
Reduce number of parameters and increase data locality.
This saves ~275 bytes of code on x86_64.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260130210303.3888261-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When we expect an IPv4 dst, use dst4_mtu() instead of dst_mtu()
to save some code space.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260130210303.3888261-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When we expect an IPv6 dst, use dst6_mtu() instead of dst_mtu()
to save some code space.
Due to current dst6_mtu() implementation, only convert
users in IPv6 stack.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260130210303.3888261-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
