is this something you want more info from?

[lentilwallop]

[131647.339680] ------------[ cut here ]------------
[131647.339692] WARNING: CPU: 22 PID: 0 at net/mptcp/mptcp_ctrl.c:624 mptcp_sock_def_error_report+0x133/0x140
[131647.339694] Meta already closed i_rcv 0 i_snd 1 send_i 1 flags 0x2004301
[131647.339695] Modules linked in: ipheth(E) bnep(E) ipmi_si(E) dell_rbu(E) nf_conntrack_netlink(E) nfnetlink(E) bluetooth(E) msr(E) nf_nat_h323(E) nf_conntrack_h323(E) nf_nat_pptp(E) nf_nat_proto_gre(E) nf_conntrack_pptp(E) nf_conntrack_proto_gre(E) nf_nat_tftp(E) nf_conntrack_tftp(E) nf_nat_sip(E) nf_conntrack_sip(E) nf_nat_irc(E) nf_conntrack_irc(E) nf_nat_ftp(E) nf_conntrack_ftp(E) overlay(E) sch_fq_codel(E) zunicode(PO) znvpair(PO) zavl(PO) xt_nat(E) xt_CHECKSUM(E) xt_addrtype(E) xfs(E) xfrm_user(E) xfrm_algo(E) vhost_scsi(E) vhost(E) veth(E) ufs(E) usb_f_tcm(E) tcm_usb_gadget(E) tcm_qla2xxx(E) tcm_loop(E) tcm_fc(E) target_core_pscsi(E) target_core_iblock(E) target_core_file(E) spl(OE) snd_hda_codec_hdmi(E) snd_hda_intel(E) snd_hda_codec(E) snd_hda_core(E) snd_hwdep(E) snd_pcm(E) snd_seq_midi(E)
[131647.339741]  snd_seq_midi_event(E) snd_rawmidi(E) snd_seq(E) snd_seq_device(E) usbhid(E) snd_timer(E) snd(E) soundcore(E) shpchp(E) wmi(E) ses(E) serio_raw(E) rt2800usb(E) rt2x00usb(E) rt2800lib(E) rt2x00lib(E) raid456(E) raid10(E) raid1(E) raid0(E) nf_conntrack_ipv6(E) nf_defrag_ipv6(E) xt_tcpudp(E) xt_conntrack(E) radeon(E) ttm(E) qnx4(E) qla2xxx(E) psmouse(E) pata_acpi(E) ntfs(E) multipath(E) msdos(E) mptctl(E) mptbase(E) minix(E) mac_hid(E) mac80211(E) lpc_ich(E) linear(E) libfc(E) libcrc32c(E) libcomposite(E) udc_core(E) kvm_intel(E) kvm(E) joydev(E) jfs(E) iscsi_target_mod(E) target_core_mod(E) irqbypass(E) ipt_REJECT(E) nf_reject_ipv4(E) ipt_MASQUERADE(E) nf_nat_masquerade_ipv4(E) iptable_nat(E) nf_conntrack_ipv4(E) nf_defrag_ipv4(E) nf_nat_ipv4(E) nf_nat(E) nf_conntrack(E) iptable_mangle(E)
[131647.339793]  iptable_filter(E) ipmi_ssif(E) ipmi_devintf(E) ipmi_msghandler(E) ip6table_filter(E) ip6_tables(E) ioatdma(E) intel_powerclamp(E) input_leds(E) i7core_edac(E) i2c_algo_bit(E) hid_generic(E) hid(E) hfsplus(E) hfs(E) gpio_ich(E) ghash_clmulni_intel(E) fjes(E) enclosure(E) edac_core(E) ebtable_filter(E) ebtables(E) drm_kms_helper(E) fb_sys_fops(E) syscopyarea(E) sysfillrect(E) sysimgblt(E) drm(E) dm_mirror(E) dm_region_hash(E) dm_log(E) dcdbas(E) dca(E) crct10dif_pclmul(E) crc32_pclmul(E) cpuid(E) coretemp(E) configfs(E) cfg80211(E) ccm(E) btrfs(E) br_netfilter(E) bridge(E) stp(E) llc(E) bnx2(E) binfmt_misc(E) async_raid6_recov(E) async_pq(E) async_xor(E) xor(E) raid6_pq(E) async_memcpy(E) async_tx(E) arc4(E) ansi_cprng(E) amdkfd(E) amd_iommu_v2(E) aesni_intel(E) aes_x86_64(E) lrw(E) glue_helper(E)
[131647.339839]  nfsd(E) acpi_power_meter(E) ablk_helper(E) auth_rpcgss(E) cryptd(E) nfs_acl(E) lockd(E) parport_pc(E) grace(E) ppdev(E) sunrpc(E) lp(E) parport(E) ip_tables(E) x_tables(E) autofs4(E) [last unloaded: ipmi_si]
[131647.339855] CPU: 22 PID: 0 Comm: swapper/22 Tainted: P        W IOE   4.9.87+ #7
[131647.339856] Hardware name: Dell Inc. PowerEdge R710/0YDJK3, BIOS 6.4.0 07/23/2013
[131647.339858]  ffff90e8ff8c3ce8 ffffffffab41ed43 ffff90e8ff8c3d38 0000000000000000
[131647.339862]  ffff90e8ff8c3d28 ffffffffab084b2b 0000027000000000 ffff90e8d5244a40
[131647.339865]  ffff90e2ced56300 ffff90e7cd639500 ffffffffac10c180 ffff90e8d5244a40
[131647.339868] Call Trace:
[131647.339870]  <IRQ> 
[131647.339878]  [<ffffffffab41ed43>] dump_stack+0x63/0x90
[131647.339883]  [<ffffffffab084b2b>] __warn+0xcb/0xf0
[131647.339886]  [<ffffffffab084baf>] warn_slowpath_fmt+0x5f/0x80
[131647.339889]  [<ffffffffab941853>] mptcp_sock_def_error_report+0x133/0x140
[131647.339893]  [<ffffffffab8b0f9f>] tcp_write_err+0x2f/0x50
[131647.339896]  [<ffffffffab8b142f>] tcp_write_timeout+0x8f/0x400
[131647.339898]  [<ffffffffab8b21e0>] ? tcp_write_timer_handler+0x220/0x220
[131647.339900]  [<ffffffffab8b1d4f>] tcp_retransmit_timer+0x2af/0x520
[131647.339905]  [<ffffffffab0ba411>] ? cpu_load_update+0xe1/0x150
[131647.339910]  [<ffffffffab949482>] mptcp_sub_retransmit_timer+0x12/0xd0
[131647.339912]  [<ffffffffab8b205c>] tcp_write_timer_handler+0x9c/0x220
[131647.339914]  [<ffffffffab8b2298>] tcp_write_timer+0xb8/0xc0
[131647.339920]  [<ffffffffab0f7187>] call_timer_fn+0x37/0x130
[131647.339922]  [<ffffffffab0f74eb>] run_timer_softirq+0x22b/0x4d0
[131647.339927]  [<ffffffffab10018e>] ? ktime_get+0x3e/0xb0
[131647.339932]  [<ffffffffab053f63>] ? lapic_next_event+0x23/0x30
[131647.339934]  [<ffffffffab106c97>] ? clockevents_program_event+0x87/0x130
[131647.339939]  [<ffffffffab97ef02>] __do_softirq+0xf2/0x286
[131647.339943]  [<ffffffffab08b1a6>] irq_exit+0xb6/0xc0
[131647.339945]  [<ffffffffab97e988>] smp_apic_timer_interrupt+0x48/0x60
[131647.339948]  [<ffffffffab97d1e6>] apic_timer_interrupt+0x96/0xa0
[131647.339949]  <EOI> 
[131647.339954]  [<ffffffffab7e8aef>] ? cpuidle_enter_state+0x9f/0x300
[131647.339957]  [<ffffffffab7e8d87>] cpuidle_enter+0x17/0x20
[131647.339960]  [<ffffffffab0cac03>] call_cpuidle+0x23/0x40
[131647.339963]  [<ffffffffab0cae6e>] cpu_startup_entry+0x14e/0x230
[131647.339965]  [<ffffffffab05297f>] start_secondary+0x16f/0x1b0
[131647.339967] ---[ end trace d0e5cfc91c5e2798 ]---

[matttbe]

Hi @lentilwallop

Thank you for the bug report.

Could you tell us what the system was doing when you had this warning?

I see that this issue was with an old kernel (4.9.87). Could you reproduce it with the latest version of our mptcp_v0.95 or mptcp_v0.94 branch please?

http://multipath-tcp.org/pmwiki.php/Users/DoItYourself

[lentilwallop]

nothing special, I believe. Just my daily driver. I just noticed the 5.6 kernel has MPTCP, so I might just hop over to that... I can reply back if any funny business. I just happened to notice several items in dmesg. system is kind of a mess currently...

[matttbe]

OK thx.

Note that the kernel 5.6 has a preliminary version of MPTCP: it only supports 1 path. If it is enough for you, feel free to use this one.