[Weekly meetings] MoM - 25th of March 2026

[Matthieu Baerts <matttbe@kernel.org>]

Hello everyone,

This week, we had our new meeting with Mat (Cruise), and myself
(NGI0 Core).


Thanks again for this new good meeting!


Here are the minutes of the meeting:



Accepted patches:
    - The list of accepted patches can be seen on PatchWork:
      https://patchwork.kernel.org/project/mptcp/list/?state=3


    netdev (if mptcp ML is in cc) (by: Li Xiasong, Matthieu Baerts, Keita Morisaki, Simon Baatz):

14449624: [net,1/5] selftests: mptcp: more stable simult_flows tests
14449625: [net,2/5] mptcp: pm: avoid sending RM_ADDR over same subflow
14449626: [net,3/5] selftests: mptcp: join: check RM_ADDR not sent over same subflow
14449627: [net,4/5] mptcp: pm: in-kernel: always mark signal+subflow endp as used
14449628: [net,5/5] selftests: mptcp: join: check removing signal+subflow endp:
    - Series: mptcp: misc fixes for v7.0-rc2
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1060560&state=*&archive=both

14460614: [net-next,v3,1/6] tcp: implement RFC 7323 window retraction receiver requirements
14460615: [net-next,v3,2/6] mptcp: keep rcv_mwnd_seq in sync with subflow rcv_wnd
14460616: [net-next,v3,3/6] tcp: increase LINUX_MIB_BEYOND_WINDOW for SKB_DROP_REASON_TCP_OVERWINDOW
14460617: [net-next,v3,4/6] selftests/net: packetdrill: add tcp_rcv_wnd_shrink_nomem.pkt
14460618: [net-next,v3,5/6] selftests/net: packetdrill: add tcp_rcv_wnd_shrink_allowed.pkt
14460619: [net-next,v3,6/6] selftests/net: packetdrill: add tcp_rcv_neg_window.pkt:
    - Series: tcp: RFC 7323-compliant window retraction handling
    - Submitter: Simon Baatz
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1063485&state=*&archive=both

14483786: [net] MPTCP: fix lock class name family in pm_nl_create_listen_socket:
    - Submitter: Li Xiasong
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260319112159.3118874-1-lixiasong1@huawei.com/


14451810: [net-next,V2,RESEND] tcp: shrink per-packet memset in __tcp_transmit_skb():
    - Submitter: Keita Morisaki
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260304111517.2088694-1-kmta1236@gmail.com/


    our repo (by: Matthieu Baerts):

14427551: [mptcp-net] mptcp: pm: in-kernel: always mark signal+subflow endp as used:
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260218-mptcp-issue-613-v1-1-f8e9adb12010@kernel.org/

14428224: [mptcp-net] selftests: mptcp: join: check removing signal+subflow endp:
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260219101033.716403-2-matttbe@kernel.org/

14429639: [mptcp-net,v2,1/2] mptcp: pm: avoid sending RM_ADDR over same subflow
14429640: [mptcp-net,v2,2/2] selftests: mptcp: join: check RM_ADDR not sent over same subflow:
    - Series: mptcp: pm: avoid sending RM_ADDR over the same subflow
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1055875&state=*&archive=both

14432575: [mptcp-next] mptcp: pm: in-kernel: remove mptcp_pm_has_addr_attr_id:
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260223-mptcp_pm_has_addr_attr_id-v1-1-1efb38ad6488@kernel.org/

14432728: [mptcp-next] selftests: mptcp: join: recreate signal endp with same ID:
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260223-mptcp-sft-re-use-id-v1-1-ec648a8bda22@kernel.org/



Pending patches:
    - The list of pending patches can be seen on PatchWork:
      https://patchwork.kernel.org/project/mptcp/list/?state=*


    netdev (if mptcp ML is in cc) (by: Li Xiasong, Matthieu Baerts):

14461679: [net-next,1/2] mptcp: better mptcp-level RTT estimator
14461680: [net-next,2/2] mptcp: add receive queue awareness in tcp_rcv_space_adjust():
    - Series: mptcp: autotune related improvement
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1063766&state=*&archive=both

14492176: [net,v2] mptcp: fix soft lockup in mptcp_recvmsg():
    - Submitter: Li Xiasong
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260324085131.4187473-1-lixiasong1@huawei.com/
    - v3 is expected.
    - Funny to see different AI reviews for that one:
        - https://sashiko.dev/#/patchset/20260324085131.4187473-1-lixiasong1%40huawei.com → Google
        - https://netdev-ai.bots.linux.dev/ai-review.html?id=4d7f2ec2-b646-4362-a319-b37727b095d6 → Claude on Netdev
        - https://netdev-ai.bots.linux.dev/ai-review.html?id=fc105106-677e-44c6-8189-ab8feef032aa → Claude on MPTCP


    our repo (by: Christoph Paasch, Gang Yan, Geliang Tang, Gregory Detal, Matthieu Baerts):

12282223: [RESEND,RFC,mptpcp-next] mptcp: add ooo prune support:
13070467: [mptcp-next,v4,1/2] mptcp: update mptcp_push_release
13070468: [mptcp-next,v4,2/2] mptcp: retrans for redundant sends:
    - State: Changes requested
    - Series: BPF redundant scheduler, part 3
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=703615&state=*&archive=both
    - status: same as last time

13305089: [mptcp-next,1/6] mptcp: sockopt: move tcp_inq code to a dedicated function
13305091: [mptcp-next,2/6] mptcp: sockopt: update supported list
13305093: [mptcp-next,3/6] mptcp: sockopt: get val in a generic way
13305090: [mptcp-next,4/6] mptcp: sockopt: add missing getsockopt() options
13305094: [mptcp-next,5/6] mptcp: sockopt: set val in a generic way
13305092: [mptcp-next,6/6] mptcp: sockopt: support IP_TTL & IPV6_UNICAST_HOPS:
    - State: Changes requested
    - Series: mptcp: sockopt: uniform code to get/set values
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=763505&state=*&archive=both
    - status: same as last time

13583230: [RFC] mptcp: react scheduler when subflow events pop up:
    - State: Changes requested
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/patch/433320c3a9db77bea53a34fc9c43a3c7e3320399.1709693691.git.tanggeliang@kylinos.cn/
    - status: same as last time

13675217: [mptcp-next,RFC,1/4] mptcp: add push sched callback
13675218: [mptcp-next,RFC,2/4] mptcp: use new push callback to schedule chunks
13675219: [mptcp-next,RFC,3/4] mptcp: bpf: allow to write to mptcp_sched_chunk
13675220: [mptcp-next,RFC,4/4] selftests/bpf: mptcp RR: send 1 MSS on each subflow:
    - State: RFC
    - Series: mptcp: update scheduler API
    - Submitter: Gregory Detal
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=856158&state=*&archive=both
    - status: same as last time

13932555: [1/3] mptcp: fix invalid addr occupy 'add_addr_accepted'
13932556: [2/3] selftests: mptcp: relax conditions in SYN_TX validation
13932546: [3/3] selftests: mptcp: add a testcase for invalid addr timeout:
    - State: Changes requested
    - Series: [1/3] mptcp: fix invalid addr occupy 'add_addr_accepted'
    - Submitter: Gang Yan
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=923771&state=*&archive=both
    - status: same as last time

14024767: [mptcp-next,v1,1/4] bpf: Add mptcp path manager struct_ops
14024768: [mptcp-next,v1,2/4] bpf: Export mptcp path manager kfuncs
14024769: [mptcp-next,v1,3/4] selftests/bpf: Add mptcp netlink pm subtest
14024770: [mptcp-next,v1,4/4] selftests/bpf: Add mptcp bpf_netlink pm subtest:
    - State: Changes requested
    - Series: BPF path manager, part 7
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=946095&state=*&archive=both
    - status: same as last time

14053397: [mptcp-next,v3,1/3] mptcp: pm: userspace: drop delete_local_addr helper
14053398: [mptcp-next,v3,2/3] selftests: mptcp: join: update userspace dump_addr outputs
14053399: [mptcp-next,v3,3/3] selftests: mptcp: userspace: send RM_ADDR between server and client:
    - State: Under review
    - Series: only remove entry from local_addr_list when sending a REMOVE_ADDR
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=953862&state=*&archive=both
    - status: same as last time

14167004: [mptcp-next] mptcp: remove redundant orig_offset in carve_data_frag:
    - State: Changes requested
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/patch/9c663fc37767d9036379afdbc83cd8874a7b2fc9.1753337130.git.tanggeliang@kylinos.cn/
    - status: same as last time

14175678: [mptcp-next,1/2] mptcp: Add support for SO_MAX_PACING_RATE
14175679: [mptcp-next,2/2] selftests: Add tests for SO_MAX_PACING_RATE:
    - State: Changes requested
    - Series: mptcp: Add support for SO_MAX_PACING_RATE
    - Submitter: Christoph Paasch
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=987909&state=*&archive=both
    - status: same as last time

14185125: [mptcp-next,1/6] mptcp: add helper for setsockopt on first subflow only
14185126: [mptcp-next,2/6] mptcp: handle SOL_SOCKET options on first subflow only
14185128: [mptcp-next,3/6] mptcp: refactor IP socket option handling for first subflow
14185127: [mptcp-next,4/6] mptcp: extract IPv6 socket option handling for first subflow
14185129: [mptcp-next,5/6] mptcp: handle SOL_TCP options on all subflows
14185130: [mptcp-next,6/6] mptcp: handle IP socket options on all subflows:
    - State: Needs ack
    - Series: refactor MPTCP socket option handling
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=990414&state=*&archive=both
    - status: same as last time

14185142: [mptcp-next,v2,1/3] mptcp: add IPV6_TCLASS socket option support
14185143: [mptcp-next,v2,2/3] mptcp: add IP_TTL socket option support
14185144: [mptcp-next,v2,3/3] mptcp: add IPV6_UNICAST_HOPS socket option support:
    - State: Needs ack
    - Series: mptcp: add more sockopts
    - Submitter: Geliang Tanghttps://github.com/sashiko-dev/sashiko/issues/50
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=990418&state=*&archive=both
    - status: same as last time

14197780: [mptcp-next,v2,01/10] selftests: mptcp: sockopt: improve test output clarity
14197781: [mptcp-next,v2,02/10] selftests: mptcp: sockopt: add SO_REUSEADDR test helper
14197782: [mptcp-next,v2,03/10] selftests: mptcp: sockopt: add SO_REUSEPORT test
14197783: [mptcp-next,v2,04/10] selftests: mptcp: sockopt: add SO_BINDTODEVICE test
14197784: [mptcp-next,v2,05/10] selftests: mptcp: sockopt: add SO_BINDTOIFINDEX test
14197785: [mptcp-next,v2,06/10] selftests: mptcp: sockopt: add IP_FREEBIND tests
14197786: [mptcp-next,v2,07/10] selftests: mptcp: sockopt: add IP_TRANSPARENT tests
14197787: [mptcp-next,v2,08/10] selftests: mptcp: sockopt: add IP_BIND_ADDRESS_NO_PORT test
14197788: [mptcp-next,v2,09/10] selftests: mptcp: sockopt: add IP_LOCAL_PORT_RANGE test
14197789: [mptcp-next,v2,10/10] selftests: mptcp: sockopt: add IPV6_V6ONLY test:
    - State: Changes requested
    - Series: selftests: cover more MPTCP socket options
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=993905&state=*&archive=both
    - status: same as last time

14215849: [mptcp-net,v2,1/3] selftests: mptcp: close server file descriptor
14215850: [mptcp-net,v2,2/3] selftests: mptcp: close IPC descriptor on server side
14229120: [mptcp-next,v4,1/9] selftests: mptcp: sockopt: replace /dev/urandom with getrandom
14229121: [mptcp-next,v4,2/9] selftests: mptcp: sockopt: add protocol arguments
14229122: [mptcp-next,v4,3/9] selftests: mptcp: sockopt: add inq argument
14229123: [mptcp-next,v4,4/9] selftests: mptcp: sockopt: rename pipefd to ipcfd
14229124: [mptcp-next,v4,5/9] selftests: mptcp: sockopt: set TCP_INQ sockopt
14229125: [mptcp-next,v4,6/9] selftests: mptcp: sockopt: handle INQ on server side
14229126: [mptcp-next,v4,7/9] selftests: mptcp: sockopt: handle INQ on client side
14229127: [mptcp-next,v4,8/9] selftests: mptcp: sockopt: replace mptcp_inq with sockopt
14229128: [mptcp-next,v4,9/9] selftests: mptcp: sockopt: remove obsolete mptcp_inq:
    - State: Changes requested
    - Series: selftests: consolidate TCP_INQ testing into sockopt
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1001827&state=*&archive=both
    - status: same as last time

14332026: [RFC,mptcp-next] mptcp: support net.ipv4.tcp_rcvbuf_low_rtt:
    - State: Changes requested
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20251127-mptcp-tcp_rcvbuf_low_rtt-v1-1-fa080d67f2e5@kernel.org/
    - status: same as last time

14413156: [mptcp-net,1/3] mptcp: add backlog_list bug reproducer test
14413157: [mptcp-net,2/3] mptcp: fix receive stalls when 'ack_seq' in backlog_list
14443235: [RESEND,mptcp-net,v2] mptcp: fix stall because of data_ready:
    - State: Changes requested
    - Submitter: Gang Yan
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260228011511.440437-1-gang.yan@linux.dev/
    - status: same as last time

14456317: [RESEND,mptcp-net] mptcp: sync the msk->sndbuf at accept() time:
    - State: New
    - Submitter: Gang Yan
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260306062316.1333680-1-gang.yan@linux.dev/
    - TODO: Matth: check with Paolo → WIP

14460375: [mptcp-next] mptcp: preserve MSG_EOR semantics in sendmsg path:
    - State: New
    - Submitter: Gang Yan
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260309025431.125943-1-gang.yan@linux.dev/
    - TODO: Matth: check AI review and reply → done

14472498: [RFC,mptcp-next,v5,1/7] mptcp: add sk_is_msk helper
14472499: [RFC,mptcp-next,v5,2/7] mptcp: add sock_set_nodelay
14472500: [RFC,mptcp-next,v5,3/7] mptcp: add sock_set_reuseaddr
14472501: [RFC,mptcp-next,v5,4/7] nvmet-tcp: add mptcp support
14472502: [RFC,mptcp-next,v5,5/7] mptcp: add sock_set_syncnt
14472503: [RFC,mptcp-next,v5,6/7] nvme-tcp: add mptcp support
14472504: [RFC,mptcp-next,v5,7/7] selftests: mptcp: add NVMe over MPTCP test:
    - State: New
    - Series: VME over MPTCP
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1066056&state=*&archive=both
    - Depends on ↓ "mptcp: fix stall because of data_ready"

14478424: [mptcp-net,v3,1/3] mptcp: replace backlog_list with backlog_queue
14478425: [mptcp-net,v3,2/3] mptcp: fix the stall problems using backlog_queue
14478426: [mptcp-net,v3,3/3] mptcp: fix the stall problems with data_ready:
    - State: Changes requested
    - Series: mptcp: fix stall because of data_ready
    - Submitter: Gang Yan
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1067816&state=*&archive=both
    - Some issues spot by AI review and during testing by Geliang

14478733: [RESEND,mptcp-next,v2,1/3] tcp: export do_tcp_splice_eof
14478734: [RESEND,mptcp-next,v2,2/3] mptcp: implement .splice_eof
14478735: [RESEND,mptcp-next,v2,3/3] selftests: mptcp: connect: trigger splice_eof:
    - State: New
    - Series: implement .splice_eof
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1067870&state=*&archive=both
    - TODO: Matth: review → done

14478764: [RESEND,mptcp-next,v2,1/2] mptcp: check desc->count in read_sock
14478765: [RESEND,mptcp-next,v2,2/2] tcp: add recv_should_stop helper:
    - State: New
    - Series: add tcp_recv_should_stop helper
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1067876&state=*&archive=both
    - Patch 2/2 looks OK but is not a simple refactoring as stated, but patch 1/2:
        - is it a fix?
        - or just some extra code that is not needed but doesn't hurt → in this case the patch is not needed
        - TODO: Matth: reply on ML → Done

14478884: [mptcp-net,v2] mptcp: fix data-race in __mptcp_retrans / mptcp_incoming_options:
    - State: Queued
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/patch/20260317-mptcp-data-race-snd_una-v2-1-2caac60de92a@kernel.org/
    - patch is OK, but likely other places to fix as well → TODO Matth

14481348: [mptcp-next,v3,1/2] mptcp: implement psock_update_sk_prot
14481349: [mptcp-next,v3,2/2] selftests/bpf: Update sockmap tests for MPTCP:
    - State: New
    - Series: implement psock_update_sk_prot
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1068551&state=*&archive=both
    - AI review found some issues: https://netdev-ai.bots.linux.dev/ai-review.html?id=57d21956-629b-4fcd-ba95-310317b0f175
    - legit?

14483678: [RFC,mptcp-next,v11,01/15] tls: introduce struct tls_prot_ops for protocol ops
14483679: [RFC,mptcp-next,v11,02/15] tls: add tls_prot_ops pointer to tls_context
14483680: [RFC,mptcp-next,v11,03/15] tls: add MPTCP SKB offset check in strp queue walk
14483681: [RFC,mptcp-next,v11,04/15] mptcp: update mptcp_check_readable for TLS use
14483682: [RFC,mptcp-next,v11,05/15] mptcp: avoid sleeping in read_sock path under softirq
14483683: [RFC,mptcp-next,v11,06/15] mptcp: implement tls_mptcp_ops for MPTCP TLS
14483684: [RFC,mptcp-next,v11,07/15] tls: disable device offload for MPTCP sockets
14483685: [RFC,mptcp-next,v11,08/15] mptcp: update ULP getsockopt for TLS support
14483686: [RFC,mptcp-next,v11,09/15] mptcp: enable ULP setsockopt for TLS support
14483687: [RFC,mptcp-next,v11,10/15] selftests: mptcp: connect: use espintcp for ULP test
14483688: [RFC,mptcp-next,v11,11/15] selftests: tls: add mptcp variant for testing
14483689: [RFC,mptcp-next,v11,12/15] selftests: tls: increase nonblocking data size for MPTCP
14483690: [RFC,mptcp-next,v11,13/15] selftests: tls: wait TCP_CLOSE in shutdown_reuse for MPTCP
14483691: [RFC,mptcp-next,v11,14/15] selftests: tls: add MPTCP test cases
14483692: [RFC,mptcp-next,v11,15/15] selftests: mptcp: cover mptcp tls tests:
    - State: New
    - Series: MPTCP KTLS support
    - Submitter: Geliang Tang
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1069182&state=*&archive=both
    - Needs to be reviewed

14492302: [6.1.y,1/2] selftests: mptcp: join: implicit: stop transfer after last check
14492303: [6.1.y,2/2] selftests: mptcp: join: check removing signal+subflow endp:
    - State: New
    - Series: selftests: mptcp: specific fixes for v6.1
    - Submitter: Matthieu Baerts
    - URL: https://patchwork.kernel.org/project/mptcp/list/?series=1071541&state=*&archive=both


Issues on GitHub:
    https://github.com/multipath-tcp/mptcp_net-next/issues/

    Recently opened (latest from the last meeting: 618):

None.


    Bugs (opened, flagged as "bug" and assigned)

  575  sockopt: support `TCP_MD5SIG` and `TCP_MD5SIG_EXT` for transparent integrations [bug] @geliangtang
  498  in-kernel PM: closed subflows before `RM_ADDR` will not decrement `add_addr_accepted` [bug] [pm] @geliangtang
  484  BPF: `setsockopt` on an MPTCP socket: check support [bug] [bpf] @geliangtang
  445  MPTCP Info counters: start seq numbers ones from 0 [bug] @geliangtang
  403  userspace pm: only remove entry from `local_addr_list` when sending a `REMOVE_ADDR` [bug] [pm] @geliangtang
  343  scheduler: react when subflow-level events pop up (ACK/RTO) [bug] [sched] @geliangtang


    Bugs (opened and flagged as "bug" and not assigned)

  616  Subflow on a inactive and disconnected network path disconnects after ~16 minutes [bug]
  602  A query about the update of 'msk->sk_sndbuf' [bug]
  600  mptcp: avoid dropping partial packets [bug]
  599  [syzbot] possible deadlock in `mptcp_subflow_create_socket`: `nbd` has a lockdep dependency between `reclaim` and `af_socket` [bug] [syzkaller]
  592  Lower throughput with MPTCP vs TCP [bug]
  587  in-kernel PM: Server is only using single IP to establish subflows [bug]
  583  KMemLeak: from `mptcp_sk_clone_init()` [bug] [selftests]
  581  Default scheduler under-utilizes newly restored subflows on long-lived flows after WAN failback [bug]
  572  [syzkaller] WARNING in `skb_try_coalesce` [bug] [syzkaller]
  549  pm: in-kernel: set `msk->pm.work_pending` back to `true` [bug] [pm]
  492  userspace pm: subflows counter: not updated when a subflows is removed from the other end [bug]
  491  selftests: `mptcp_join`: tests `Infinite map` & `MP_FAIL MP_RST` are unstable [bug] [selftests]
  483  [6.1] selftests: `mptcp_connect.sh` failures with `copyfd_io_poll: poll timed out` errors [bug] [selftests]
  475  `simult_flows`: unbalanced bwidth tests are unstable [bug] [selftests]
  439  mptcp vs net.ipv4.tcp_shrink_window [bug]
  336  Issues with BPF packet scheduler [bug] [sched] [bpf]


    In Progress (opened, new feature and assigned)

  568  socket option: support `IPV6_TCLASS` [enhancement] @geliangtang
  521  Implement psock_update_sk_prot, for eBPF SOCKMAP support [enhancement] [bpf] @geliangtang
  480  MPTCP and KTLS support [enhancement] @geliangtang
  434  in-kernel PM: increase subflows limit [enhancement] [pm] @matttbe
  353  sockopt: uniform code to get/set values [enhancement] @matttbe
  349  scheduler: (un)mark a subflow as "stale" [enhancement] [sched] @geliangtang
  296  Support IP_TTL & IPV6_UNICAST_HOPS [enhancement] @matttbe
  167  packetdrill: add coverage for RM_ADDR [enhancement] [packetdrill] @dcaratti
   75  BPF: packet scheduler [enhancement] [sched] [bpf] @geliangtang
   74  BPF: path manager [enhancement] [pm] [bpf] @geliangtang


    Assigned Questions (opened, questions and assigned)

  548  disable mptcp for an interface [question] @matttbe


    Open questions (opened, questions and not assigned)

  562  [performance] How much is the overhead of MPTCP？ [question]


    For later (opened and not assigned)

  618  `TCP_RTO_MIN`/`MAX`: used configured values if any [enhancement]
  610  MPTCP tree in `linux-next` [enhancement]
  590  in-kernel PM: use either `subflow` or `signal` depending on connector/listener app [enhancement]
  588  in-kernel PM: support NUMA awareness [enhancement] [feedback-needed]
  584  [syzkaller] improve coverage [syzkaller]
  578  sockopt: support `SO_MAX_PACING_RATE` to limit the whole MPTCP connection [enhancement]
  566  pm: use `signal` + `subflow` + `fullmesh` [enhancement] [pm]
  556  Implement all required bits to C/R MPTCP connections from user-space (CRIU) [enhancement]
  552  pm: in-kernel: delay before creating new subflows [enhancement]
  545  Deal with multiple pure TCP ACK without MPTCP options [enhancement]
  543  TCPDump: display `MP_TCPRST` info [enhancement]
  542  in-kernel PM: limit to one subflow per network interface for each connection [enhancement] [pm]
  535  TCPDump: display `MP_CAPABLE` C flag [enhancement]
  525  tests: cover more MPTCP socket options [enhancement] [packetdrill] [selftests]
  519  Reset the connection once "MPTCP has been verified" instead of a fallback [enhancement]
  511  Add MIB counters for sent `MPTCP_RST_EMPTCP` [enhancement]
  497  in-kernel PM: check to create new subflows when some are destroyed [enhancement] [pm]
  496  in-kernel PM: store received `ADD_ADDR` [enhancement] [pm]
  481  remove refcount on TCP sockets for the timers [enhancement]
  467  Scheduler: add redundant scheduler support in BPF [enhancement] [sched]
  462  selftests: print (and set?) random seed [enhancement] [selftests]
  461  Protocol: extend Data-Level Length field [enhancement] [protocol]
  448  Allow sending ADD_ADDR IPv6 with port-number if TCP-timestamps are enabled [enhancement]
  441  optimize established options generation [enhancement]
  440  in-kernel PM: re-establish subflows after "network" errors [enhancement] [pm]
  426  selftests: validate listener sockets with multiple accepts [enhancement] [selftests]
  389  packetdrill: increase coverage for "early `close()`" cases [enhancement] [packetdrill]
  350  scheduler: API changes (tasks) [enhancement] [sched]
  348  scheduler: frequently probe "stale" subflow with reinjected data [enhancement] [sched]
  345  scheduler: "penalise" some subflows by sending less than their cwnd [enhancement] [sched]
  344  scheduler: new callback to initiate optimisations [enhancement] [sched]
  337  in-kernel PM: listen socket: support "behind a NAT" use case  [enhancement] [pm]
  335  Server to Client subflows: option to allow joining the initial address and port [enhancement] [pm]
  334  in-kernel PM: send >1 ADD_ADDR before the establishment of a new subflow [enhancement] [pm]
  332  scheduler: implement a "opportunistic retransmission" [enhancement] [sched]
  289  mptcp: audit comments for non inclusive language [enhancement]
  273  Packetdrill: test outgoing MP_FASTCLOSE [enhancement] [packetdrill]
  266  Packetdrill: add MP_FAIL coverage [packetdrill]
  236  Review supported sockopts list [enhancement]
  234  Packetdrill: Support MPC+DATA+checksum error [enhancement] [packetdrill]
  222  Netlink event API: add SUBFLOW_CREATED event [enhancement]
  215  TCP Urgent pointer and MPTCP [enhancement]
  213  add MPTCP man page [enhancement]
  208  better handing of ssk memory pressure in the TX path [enhancement]
  202  Add sendmsg support for ancillary data [enhancement]
  180  Get an update when MPTCP fall back to TCP [enhancement]
  177  improve retransmit subflow selection [enhancement]
  169  packetdrill: add coverage for ADD_ADDR and MP_JOIN on a different port [enhancement] [packetdrill]
  150  remove completely workqueue usage [enhancement]
  141  avoid acquiring mptcp_data_lock() twice in the receive path [enhancement]
   78  notify the application (userspace) when a subflow is added/removed [enhancement]
   41  reduce indirect call usage [enhancement]
   24  Revisit layout of struct mptcp_subflow_context [enhancement]


    Recently closed (since 2026-03-11)

  617  CI: Stalls when starting a VSOCK listening socket: soft lockups, RCU stalls, timeout [bug] [CI] @matttbe:
      - even got mentioned on Phoronix: https://www.phoronix.com/news/Linux-7.0-Sched-Fixes-Perf-Hang


    Packetdrill PRs

  189  16 days ago  Dwyane-Yan   packetdrill: mptcp: add tests for MSG_EOR:
      - Matth: TODO: check that → done

  162  1 month ago  geliangtang  mptcp: add splice test
  52   1 year ago   dcaratti     Add initial coverage for RM_ADDR


    mptcp.dev PRs: /



    mptcp-upstream-virtme-docker PRs: /



    mptcpd PRs: /



FYI: Current Roadmap:
    - Bugs: https://github.com/multipath-tcp/mptcp_net-next/issues?q=is%3Aissue+is%3Aopen+label%3Abug
    - Current/Coming merge window (7.1): https://github.com/orgs/multipath-tcp/projects/19
    - For later: https://github.com/orgs/multipath-tcp/projects/1



Patches to send to NetDev:

    - Fixes for other trees:


    - Fixes for -net:

        - [664615b26a0e] mptcp: fix soft lockup in mptcp_recvmsg() (Li Xiasong):
            - Already sent
            - a new version

    - Fixes for net-next: /


    - Features for net-next:

        - [df303635a41d] mptcp: pm: init and release mptcp_pm_ops (Geliang Tang)
        - [062587ca01fa] mptcp: pm: add get_local_id() interface (Geliang Tang)
        - [a538a6f9bc81] mptcp: pm: add get_priority() interface (Geliang Tang):
            - wait for pm->lock refactoring

        - [c2b696680946] mptcp: better mptcp-level RTT estimator (Paolo Abeni)
        - [d05f4dd1b62e] mptcp: add receive queue awareness in tcp_rcv_space_adjust() (Paolo Abeni):
            - new version needed, see AI review → TODO Paolo (or Matth?)

        - [9f01ac098cb6] mptcp: pm: in-kernel: remove mptcp_pm_has_addr_attr_id (Matthieu Baerts (NGI0))
        - [b56a02218c50] selftests: mptcp: join: recreate signal endp with same ID (Matthieu Baerts (NGI0)):
            - can wait a bit to be sent with other small refactoring

    - Features for net-next (next): /

    - Features for other trees:

        - [ead68f28763e] bpf: Add mptcp_subflow bpf_iter (Geliang Tang)
        - [5894d027dfe1] selftests/bpf: More endpoints for endpoint_init (Geliang Tang)
        - [355b0bf44f01] selftests/bpf: Drop cgroup_fd of run_mptcpify (Geliang Tang)
        - [ffc24a871489] bpf: Add mptcp packet scheduler struct_ops (Geliang Tang)
        - [cdfb6b9e0e23] bpf: Export mptcp packet scheduler helpers (Geliang Tang)
        - [f79179a227ea] selftests/bpf: Add bpf scheduler test (Geliang Tang)
        - [6aeb42300043] selftests/bpf: Add bpf_first scheduler & test (Geliang Tang)
        - [6323b7739fdf] selftests/bpf: Add bpf_bkup scheduler & test (Geliang Tang)
        - [00ced3af9699] selftests/bpf: Add bpf_rr scheduler & test (Geliang Tang)
        - [48eb8cf7400b] selftests/bpf: Add bpf_red scheduler & test (Geliang Tang)
        - [93825ab22e4e] selftests/bpf: Add bpf_burst scheduler & test (Geliang Tang):
            - wait for sched API refactoring




Extra tests:
    - news about Syzkaller? (Matth):
        - now with instances running with KCSAN and KMSAN which were not enabled before because mutually exclusive with KASAN

    - Packetdrill (Davide):
        - /

    - Patchew (Davide):
        - /

    - CI (Matth):
        - https://ci-results.mptcp.dev/flakes.html
        - https://netdev.bots.linux.dev/flakes.html?tn-needle=mptcp
        - packetdrill issues with some retransmissions, to be checked what other better solutions we can have, maybe a sysctl to avoid such spurious retransmissions or do not check results in details with a kernel in debug mode (similar to what is done on NIPA)



AI reviews:
    - MPTCP patches are also checked by Google Gemini:
        https://sashiko.dev/#/?list=dev.linux.lists.mptcp
    - Could be nice to add a link from Patchwork: TODO Matth: modify CI to poll, or check if they can add the status (one post) → Done https://github.com/sashiko-dev/sashiko/issues/50
    - Could be even better to add the status result, if we have it at that time



Next meeting:
    - Next one on Wednesday, the 8th of April.
    - 17:30 UTC (8.30am PDT, 5.30pm CEST, 11.30pm CST)
    - Still open to everyone!
    - https://annuel2.framapad.org/p/mptcp_upstreaming_20260408



Feel free to comment on these topics and suggest new ones for the next
meeting!

Talk to you soon,
Matt
-- 
Sponsored by the NGI0 Core fund.