Received: by 2002:a25:1506:0:0:0:0:0 with SMTP id 6csp5389326ybv; Tue, 11 Feb 2020 14:55:50 -0800 (PST) X-Google-Smtp-Source: APXvYqxkJCJQu2RhsD+OhVHfPUNtxp4d/jlY9AXSuOlbt+6JkGJH02KER+43tPyWvTb1esYO8SLU X-Received: by 2002:aca:7244:: with SMTP id p65mr4201404oic.50.1581461749966; Tue, 11 Feb 2020 14:55:49 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1581461749; cv=none; d=google.com; s=arc-20160816; b=sI+afEy/sAvSLjmIwWvpgbrxMHjZwzTovMRD3v9nYmU5ilsSfS5UlqZ4H3JaAdk0uV 9GXSxPnUCQ0RnVTzvqcti5kYD739B7H2u/ZXsQk6ruzwHWFI2CRH6jmWyWgDJx43a7F0 1flAUFMF+sF+A/aL2CmJxGMw763bCoLn5lzEmTKb94SQelqXH1mPnDWG1UyzkQxUNRLC +R6WX4ACSX0V5FHBRmjsc9k/+JVNsUdphzjWOaTWxUT02xe7N3lkDK6YQj6o3q7riNZs +DuJUdK3kt3/rFXBx6ZucYhnMQ/LKXff30+GRCeRWnby+HSTMMhmQfdbFo8fkKYAjxNO FFyQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:to:subject:message-id:date:from :mime-version:dkim-signature; bh=0VxmmnS4+i8suoJlSW1me6WYLLjUPfonWZSXLzBA5ko=; b=YXBgt64T5wPQPj3qjSXAkGyxPAMbwy6OEjf5G7eQoyN1f0Ha0KBlOoaNQIqCkbSQXh 011tH8viyM33j9bStXRSWyyjpuJfJK0gHEUpIdmlVz+i/5ExUA+BslT4FqxOvgsiReWp EuTgqhwyMgRaK4DFWQZ4MUR4ZtwpHzO6AA4DHCPopbeK+cB/Z+ZDnpE54rSo04FBaKrk /DDb3Ln4LFSfwNK5nrSnfU8Wda6me9n8m8/GaSRoZKMeEsYMUCLEEXXpNIOJkKhwO8tP Lb7kcKykE2lyEaEozAzQC9PcOnV/kwl7Jm89Wz5UY9tq8NVSyVULBQmDemTGoeWJ4mYB OUZw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=GeGWnpNG; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id y8si2215776oih.141.2020.02.11.14.55.36; Tue, 11 Feb 2020 14:55:49 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=GeGWnpNG; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727725AbgBKWyc (ORCPT + 99 others); Tue, 11 Feb 2020 17:54:32 -0500 Received: from mail-ed1-f53.google.com ([209.85.208.53]:41440 "EHLO mail-ed1-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727199AbgBKWyb (ORCPT ); Tue, 11 Feb 2020 17:54:31 -0500 Received: by mail-ed1-f53.google.com with SMTP id c26so70304eds.8 for ; Tue, 11 Feb 2020 14:54:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=0VxmmnS4+i8suoJlSW1me6WYLLjUPfonWZSXLzBA5ko=; b=GeGWnpNGejAg0fEJDUWR4qVzVOvY2WxEw3y9g35cBlYkABy8xN9n2RfbAvTzjEdCUY HsQdk6CVSMLNLzJDKNfDT9KtfidPIfTGskyxpBqg3CwjQBCdhN8CZyS/fTI1yZrp66l7 rMot3gBOxJLE6SIwoAIUEXW4H3ThvPihAUaKAGiQbxXSyhGZva3m8cmGfXERENx+K5tr uAbMzRIFQejkro8hi+hEUwVRgU7oZn8bRToFn/KF5M0fHNO3cBbQuYZNsung7q/zCk7y l94mrMZADl2r7ShXUGttFefxos13OKRXKuNWrav1B8zxPObtZmrCx7bM9QniLZipgXw/ nV/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=0VxmmnS4+i8suoJlSW1me6WYLLjUPfonWZSXLzBA5ko=; b=diwCSRa5ZULb8dPeInFG4BKAGiksQVFevNFd4gvKPby5KkUoHvCjclTKAYI8JAA6zK u6tEBPc7yxomPAKEe1wdlX2ZteczQZRMvxngopvpCRQ6KRN5DB7m9u2vlqF80hsIS4ap khPEi+SY2VgA3Cl2j8d1PhE8YgUuEku65RqK8qYiTDNdVPtR7otwaxOr7sxJqzD1evGP 1HkhE28EXoEZJQEcU1PSdF2as44aQCGBiz0aR7Co3sDVUke8PE/dGQD4OSlCaOZETfG2 spiANIN3NGcDgm8ZaMCGdLDE6SY7XlcFXl0WzHVr6pi3akYjBbTPYzwNlzn+MHisNlHN 8JzA== X-Gm-Message-State: APjAAAVkhAbq+A1c0j5pC44OxQmE7kKZRBXwvdC2DWD2qFpk7j32pHv4 5eiHk9tnCFpaJ0MxCOTq3dcNcILn8c5WF1OSVMElIb8t X-Received: by 2002:a17:906:80b:: with SMTP id e11mr7918933ejd.278.1581461668987; Tue, 11 Feb 2020 14:54:28 -0800 (PST) MIME-Version: 1.0 From: Vieri Di Paola Date: Tue, 11 Feb 2020 23:54:17 +0100 Message-ID: Subject: warning messages for net/ipv4/tcp_output.c To: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I get a lot of messages regarding net/ipv4/tcp_output.c in syslog. The OS works "as expected" (network router/firewall), but these messages are very frequent when there's enough network traffic. Only in one case I've seen a system freeze after one week uptime. The last recorded message was related to net/ipv4/tcp_output.c, but I have not been able to reproduce it again (kernel panic). Feb 11 16:53:40 kernel: ------------[ cut here ]------------ Feb 11 16:53:40 kernel: WARNING: CPU: 6 PID: 0 at net/ipv4/tcp_output.c:915 tcp_wfree.cold+0xc/0x13 Feb 11 16:53:40 kernel: Modules linked in: autofs4 nfnetlink_queue xt_mac xt_REDIRECT xt_limit xt_nat xt_recent xt_statistic xt_connmark xt_comment xt_iprange l2tp_netlink l2tp_core ip6_udp_tunnel udp_tunnel xt_set xt_NFQUEUE xt_AUDIT ipt_REJECT nf_reject_ipv4 xt_addrtype bridge stp llc xt_mark xt_TCPMSS xt_hashlimit xt_CT xt_multiport nfnetlink_log xt_NFLOG nf_log_ipv4 nf_log_common xt_LOG nf_nat_tftp nf_nat_snmp_basic nf_conntrack_snmp nf_nat_sip nf_nat_pptp nf_nat_proto_gre nf_nat_irc nf_nat_h323 nf_nat_ftp nf_nat_amanda ts_kmp nf_conntrack_amanda nf_conntrack_sane nf_conntrack_tftp nf_conntrack_sip nf_conntrack_pptp nf_conntrack_proto_gre nf_conntrack_netlink nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_irc nf_conntrack_h323 nf_conntrack_ftp pppoe pppox ppp_generic slhc ip_set_hash_mac ip_set_bitmap_port Feb 11 16:53:40 kernel: ip_set_hash_net ip_set_hash_ip ip_set nfnetlink ip6table_filter ip6_tables arptable_filter arp_tables xt_conntrack iptable_mangle iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_raw sch_fq tcp_cdg tcp_bbr iptable_filter ip_tables bpfilter mlx5_ib ipmi_ssif ib_uverbs edac_mce_amd kvm_amd kvm ast ttm irqbypass crct10dif_pclmul efi_pstore ghash_clmulni_intel drm_kms_helper pcspkr efivars ixgbe igb sp5100_tco mlx5_core drm joydev bnxt_en i2c_algo_bit mdio i2c_piix4 mlxfw ccp dca i2c_core ipmi_si ipmi_devintf ipmi_msghandler pinctrl_amd pcc_cpufreq acpi_cpufreq mac_hid efivarfs aesni_intel crypto_simd cryptd glue_helper aes_x86_64 algif_rng algif_aead algif_hash algif_skcipher af_alg crc32c_intel crc32_pclmul crc32_generic msdos fat cramfs overlay squashfs Feb 11 16:53:40 kernel: loop fuse f2fs xfs nfs lockd grace sunrpc fscache jfs reiserfs btrfs ext4 mbcache jbd2 multipath linear raid10 raid1 raid0 dm_zero dm_verity reed_solomon dm_thin_pool dm_switch dm_snapshot dm_raid raid456 md_mod async_raid6_recov async_memcpy async_pq raid6_pq dm_mirror dm_region_hash dm_log_writes dm_log_userspace dm_log dm_integrity async_xor async_tx xor dm_flakey dm_delay dm_crypt dm_cache_smq dm_cache dm_persistent_data libcrc32c dm_bufio dm_bio_prison dm_mod firewire_core crc_itu_t hid_sunplus hid_sony hid_samsung hid_pl hid_petalynx hid_monterey hid_microsoft hid_logitech_dj hid_logitech ff_memless hid_gyration hid_ezkey hid_cypress hid_chicony hid_cherry hid_belkin hid_apple hid_a4tech sl811_hcd ohci_hcd uhci_hcd uas usb_storage xhci_plat_hcd pata_sl82c105 pata_via pata_jmicron Feb 11 16:53:40 kernel: pata_marvell pata_netcell pata_pdc202xx_old pata_triflex pata_atiixp pata_opti pata_amd pata_ali pata_it8213 pata_pcmcia pcmcia pcmcia_core pata_ns87415 pata_ns87410 pata_serverworks pata_oldpiix pata_artop pata_it821x pata_optidma pata_hpt3x2n pata_hpt3x3 pata_hpt37x pata_hpt366 pata_cmd64x pata_efar pata_sil680 pata_pdc2027x pata_mpiix lpfc nvmet_fc qla2xxx megaraid_mbox megaraid_mm aacraid sx8 hpsa 3w_9xxx 3w_xxxx 3w_sas mptsas mptfc scsi_transport_fc atp870u dc395x qla1280 dmx3191d sym53c8xx gdth initio BusLogic arcmsr aic7xxx aic79xx sr_mod cdrom sg sd_mod mpt3sas raid_class scsi_transport_sas megaraid megaraid_sas mptspi mptscsih mptbase scsi_transport_spi pdc_adma sata_inic162x sata_mv sata_qstor sata_vsc sata_uli sata_sis pata_sis sata_sx4 sata_nv sata_via sata_svw sata_sil24 Feb 11 16:53:40 kernel: sata_sil sata_promise ata_piix ahci libahci nvme_fc nvme_loop nvmet nvme_rdma rdma_cm iw_cm ib_cm ib_core configfs ipv6 crc_ccitt nvme_fabrics nvme nvme_core Feb 11 16:53:40 kernel: CPU: 6 PID: 0 Comm: swapper/6 Not tainted 4.19.97-gentoo-x86_64 #1 Feb 11 16:53:40 kernel: Hardware name: Supermicro AS -1114S-WTRT/H12SSW-NT, BIOS 1.0b 11/15/2019 Feb 11 16:53:40 kernel: RIP: 0010:tcp_wfree.cold+0xc/0x13 Feb 11 16:53:40 kernel: Code: 9d 04 00 00 00 5b c6 85 9b 04 00 00 00 5d c3 48 c7 c7 70 93 06 b0 e8 f7 f7 94 ff 0f 0b c3 48 c7 c7 70 93 06 b0 e8 e8 f7 94 ff <0f> 0b e9 46 a5 ff ff 48 c7 c7 70 93 06 b0 e8 d5 f7 94 ff 0f 0b b8 Feb 11 16:53:40 kernel: RSP: 0018:ffff9e9c2b183d90 EFLAGS: 00010246 Feb 11 16:53:40 kernel: RAX: 0000000000000024 RBX: ffff9e9bc099cee8 RCX: 0000000000000000 Feb 11 16:53:40 kernel: RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 0000000000000300 Feb 11 16:53:40 kernel: RBP: ffff9e9bbef09980 R08: ffff9e9c2b1968b8 R09: 0000000000000001 Feb 11 16:53:40 kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff9e9bc099cee8 Feb 11 16:53:40 kernel: R13: ffff9e9a900100a8 R14: ffff9e9c0155a8c0 R15: 0000000000000026 Feb 11 16:53:40 kernel: FS: 0000000000000000(0000) GS:ffff9e9c2b180000(0000) knlGS:0000000000000000 Feb 11 16:53:40 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Feb 11 16:53:40 kernel: CR2: 00007f90cb702820 CR3: 00000007d41b2000 CR4: 0000000000340ee0 Feb 11 16:53:40 kernel: Call Trace: Feb 11 16:53:40 kernel: Feb 11 16:53:40 kernel: skb_release_head_state+0x64/0xb0 Feb 11 16:53:40 kernel: skb_release_all+0xe/0x30 Feb 11 16:53:40 kernel: consume_skb+0x27/0x80 Feb 11 16:53:40 kernel: bnxt_tx_int+0xd0/0x360 [bnxt_en] Feb 11 16:53:40 kernel: bnxt_poll+0x20f/0x870 [bnxt_en] Feb 11 16:53:40 kernel: net_rx_action+0x148/0x3b0 Feb 11 16:53:40 kernel: __do_softirq+0xe8/0x2f1 Feb 11 16:53:40 kernel: irq_exit+0x100/0x110 Feb 11 16:53:40 kernel: do_IRQ+0x81/0xe0 Feb 11 16:53:40 kernel: common_interrupt+0xf/0xf Feb 11 16:53:40 kernel: Feb 11 16:53:40 kernel: RIP: 0010:cpuidle_enter_state+0xc3/0x320 Feb 11 16:53:40 kernel: Code: e8 82 68 a0 ff 80 7c 24 0b 00 74 17 9c 58 0f 1f 44 00 00 f6 c4 02 0f 85 30 02 00 00 31 ff e8 84 55 a6 ff fb 66 0f 1f 44 00 00 <48> ba cf f7 53 e3 a5 9b c4 20 4c 29 f5 48 89 e8 48 c1 fd 3f 48 f7 Feb 11 16:53:40 kernel: RSP: 0018:ffffb4440021fe80 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffd6 Feb 11 16:53:40 kernel: RAX: ffff9e9c2b1a2200 RBX: ffff9e9c02dfe800 RCX: 000000000000001f Feb 11 16:53:40 kernel: RDX: 0000000000000000 RSI: 000000002c234d74 RDI: 0000000000000000 Feb 11 16:53:40 kernel: RBP: 000002de50bf72ea R08: 000002de50bf72ea R09: 0000000000000035 Feb 11 16:53:40 kernel: R10: 00000000ffffffff R11: ffff9e9c2b1a12e8 R12: 0000000000000002 Feb 11 16:53:40 kernel: R13: ffffffffb03954a0 R14: 000002de4de20c75 R15: ffff9e95044bcc80 Feb 11 16:53:40 kernel: do_idle+0x1dc/0x270 Feb 11 16:53:40 kernel: cpu_startup_entry+0x6f/0x80 Feb 11 16:53:40 kernel: start_secondary+0x1a7/0x200 Feb 11 16:53:40 kernel: secondary_startup_64+0xb6/0xc0 Feb 11 16:53:40 kernel: ---[ end trace 828aa59c66af655f ]--- My distribution is Gentoo. I've reported this to the Gentoo Linux devs, but unfortunately there hasn't been much progress. # grep CONFIG_KALLSYMS .config CONFIG_KALLSYMS=y CONFIG_KALLSYMS_ALL=y CONFIG_KALLSYMS_ABSOLUTE_PERCPU=y CONFIG_KALLSYMS_BASE_RELATIVE=y # emerge --info Portage 2.3.84 (python 3.6.9-final-0, default/linux/amd64/17.1, gcc-9.2.0, glibc-2.29-r7, 4.19.97-gentoo-x86_64 x86_64) ================================================================= System uname: Linux-4.19.97-gentoo-x86_64-x86_64-AMD_EPYC_7272_12-Core_Processor-with-gentoo-2.6 KiB Mem: 32800832 total, 26904664 free KiB Swap: 37007292 total, 37007292 free Timestamp of repository gentoo: Thu, 06 Feb 2020 00:45:01 +0000 Head commit of repository gentoo: e358b025b6215c284de6047b54dca1e9b981126a sh bash 4.4_p23-r1 ld GNU ld (Gentoo 2.32 p2) 2.32.0 app-shells/bash: 4.4_p23-r1::gentoo dev-java/java-config: 2.2.0-r4::gentoo dev-lang/perl: 5.30.1::gentoo dev-lang/python: 2.7.17::gentoo, 3.6.9::gentoo, 3.7.5-r1::gentoo dev-util/cmake: 3.14.6::gentoo sys-apps/baselayout: 2.6-r1::gentoo sys-apps/openrc: 0.42.1::gentoo sys-apps/sandbox: 2.13::gentoo sys-devel/autoconf: 2.69-r5::gentoo sys-devel/automake: 1.11.6-r3::gentoo, 1.15.1-r2::gentoo, 1.16.1-r1::gentoo sys-devel/binutils: 2.32-r1::gentoo sys-devel/gcc: 9.2.0-r2::gentoo sys-devel/gcc-config: 2.1::gentoo sys-devel/libtool: 2.4.6-r6::gentoo sys-devel/make: 4.2.1-r4::gentoo sys-kernel/linux-headers: 4.19::gentoo (virtual/os-headers) sys-libs/glibc: 2.29-r7::gentoo Repositories: gentoo location: /var/db/repos/gentoo sync-type: rsync sync-uri: rsync://rsync.gentoo.org/gentoo-portage priority: -1000 sync-rsync-verify-metamanifest: yes sync-rsync-verify-max-age: 24 sync-rsync-extra-opts: sync-rsync-verify-jobs: 1 CustomOverlay location: /usr/local/portage masters: gentoo ACCEPT_KEYWORDS="amd64" ACCEPT_LICENSE="*" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /etc/stunnel/stunnel.conf /usr/lib64/fax /usr/share/easy-rsa /usr/share/gnupg/qualified.txt /usr/share/maven-bin-3.6/conf /var/bind /var/spool/fax/etc" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/php/apache2-php7.3/ext-active/ /etc/php/cgi-php7.3/ext-active/ /etc/php/cli-php7.3/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /var/spool/fax/etc/xferfaxlog" CXXFLAGS="-O2 -pipe" DISTDIR="/var/cache/distfiles" ENV_UNSET="DBUS_SESSION_BUS_ADDRESS DISPLAY GOBIN PERL5LIB PERL5OPT PERLPREFIX PERL_CORE PERL_MB_OPT PERL_MM_OPT XAUTHORITY XDG_CACHE_HOME XDG_CONFIG_HOME XDG_DATA_HOME XDG_RUNTIME_DIR" FCFLAGS="-O2 -pipe" FEATURES="assume-digests binpkg-docompress binpkg-dostrip binpkg-logs buildpkg config-protect-if-modified distlocks ebuild-locks fixlafiles ipc-sandbox merge-sync multilib-strict network-sandbox news nostrip parallel-fetch pid-sandbox preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr" FFLAGS="-O2 -pipe" GENTOO_MIRRORS="http://distfiles.gentoo.org" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j25" PKGDIR="/var/cache/binpkgs" PORTAGE_BINHOST="http://inf-bl07/gentoo/binary-amd64" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --exclude=/.git" PORTAGE_TMPDIR="/var/tmp" USE="acl ads amd64 apache2 berkdb bzip2 cli cluster crypt cxx dri fortran freetds gdbm iconv ipv6 jbig kerberos ldap libtirpc logrotate multilib ncurses nls nptl odbc openmp openrc pam pcre python radius readline samba seccomp split-usr ssl tcpd unicode winbind xattr zlib" ABI_X86="64" ADA_TARGET="gnat_2018" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" APACHE2_MPMS="prefork" CALLIGRA_FEATURES="karbon sheets words" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" CPU_FLAGS_X86="aes avx avx2 f16c fma3 mmx mmxext pclmul popcnt sha sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock greis isync itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf skytraq superstar2 timing tsip tripmate tnt ublox ubx" GRUB_PLATFORMS="efi-64 pc" INPUT_DEVICES="libinput keyboard mouse" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php7-2" POSTGRES_TARGETS="postgres10 postgres11" PYTHON_SINGLE_TARGET="python3_6" PYTHON_TARGETS="python2_7 python3_6" RUBY_TARGETS="ruby24 ruby25" USERLAND="GNU" VIDEO_CARDS="amdgpu fbdev intel nouveau radeon radeonsi vesa dummy v4l" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CC, CPPFLAGS, CTARGET, CXX, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LANG, LC_ALL, LINGUAS, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS I've also tested kernel 5.5 with the same behavior. I believe kernel 4.12.12 did not have this issue, but I was running it on different hardware. I have not yet tried 4.12.12 on this particular hardware. Please note that the same issue (net/ipv4/tcp_output.c:915) ocurrs on different hardware with different NIC drivers (eg. e1000/e1000e) but with the same kernel version. Please let me know if I can provide more information or make more specific tests. Regards, Vieri