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[73.241.150.58]) by smtp.gmail.com with ESMTPSA id t16sm1361433pgo.80.2020.02.11.19.47.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 11 Feb 2020 19:47:35 -0800 (PST) Subject: Re: warning messages for net/ipv4/tcp_output.c To: Neal Cardwell , Vieri Di Paola Cc: LKML , Netdev , Eric Dumazet References: From: Eric Dumazet Message-ID: Date: Tue, 11 Feb 2020 19:47:33 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/11/20 7:17 PM, Neal Cardwell wrote: > On Tue, Feb 11, 2020 at 5:54 PM Vieri Di Paola wrote: >> >> 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 > > Thanks for the report. Please cc the Linux networking (netdev) list on > networking issues like this (I have cc-ed that e-mail list). > > This seems to be the code in question: > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/net/ipv4/tcp_output.c?h=v4.19.97#n915 > > And this seems to be the warning: > WARN_ON(refcount_sub_and_test(skb->truesize - 1, &sk->sk_wmem_alloc)); > Thanks Neal Nothing comes to mind really. If older kernels were fine, then a bisection might be the fastest way to find the root cause. There are too many changes between 4.12.12 and 5.5 to even try something else than brute force.