We are using HP ProLiant DL320e Gen8 with a dual port ConnectX-2 EN network Mellanox NIC (P/N: MNPH29D_A2-A5) installed. BIOS, iLO, microcode and NIC firwmwares are up to date. Already tried to change interrupts. All offloading features are currently disabled: Features for eth2: rx-checksumming: on tx-checksumming: on tx-checksum-ipv4: on tx-checksum-ip-generic: off [fixed] tx-checksum-ipv6: on tx-checksum-fcoe-crc: off [fixed] tx-checksum-sctp: off [fixed] scatter-gather: on tx-scatter-gather: on tx-scatter-gather-fraglist: off [fixed] tcp-segmentation-offload: on tx-tcp-segmentation: on tx-tcp-ecn-segmentation: off [fixed] tx-tcp6-segmentation: on udp-fragmentation-offload: off [fixed] generic-segmentation-offload: on generic-receive-offload: on large-receive-offload: off [fixed] rx-vlan-offload: on tx-vlan-offload: on ntuple-filters: off [fixed] receive-hashing: on highdma: on [fixed] rx-vlan-filter: on [fixed] vlan-challenged: off [fixed] tx-lockless: off [fixed] netns-local: off [fixed] tx-gso-robust: off [fixed] tx-fcoe-segmentation: off [fixed] tx-gre-segmentation: off [fixed] tx-ipip-segmentation: off [fixed] tx-sit-segmentation: off [fixed] tx-udp_tnl-segmentation: off [fixed] fcoe-mtu: off [fixed] tx-nocache-copy: off loopback: off rx-fcs: off [fixed] rx-all: off [fixed] tx-vlan-stag-hw-insert: off [fixed] rx-vlan-stag-hw-parse: on rx-vlan-stag-filter: on [fixed] l2-fwd-offload: off [fixed] busy-poll: on [fixed] When putting load on those NICs we are receiving a kpanic. The issue can be reproduced at any time. Kernel version doesn't make any difference. [ 176.892495] ------------[ cut here ]------------ [ 176.892513] kernel BUG at net/core/skbuff.c:2097! [ 176.892525] invalid opcode: 0000 [#1] SMP [ 176.892538] Modules linked in: cpufreq_stats cpufreq_userspace cpufreq_powersave iptable_filter cpufreq_conservative xt_CT nf_conntrack iptable_raw ip_tables x_tables nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc ip_gre ip_tunnel gre intel_rapl iosf_mbi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel sha256_ssse3 sha256_generic hmac drbg ansi_cprng aesni_intel mgag200 aes_x86_64 lrw ttm drm_kms_helper gf128mul glue_helper drm ablk_helper iTCO_wdt cryptd iTCO_vendor_support joydev evdev psmouse ie31200_edac serio_raw hpilo i2c_algo_bit edac_core lpc_ich hpwdt snd_pcm snd_timer snd 8250_fintek soundcore pcspkr mfd_core ipmi_si ipmi_msghandler shpchp button pcc_cpufreq acpi_cpufreq processor acpi_power_meter 8021q [ 176.892778] garp mrp stp llc dummy autofs4 ext4 crc16 mbcache jbd2 dm_mod mlx4_en vxlan ip6_udp_tunnel udp_tunnel sg sd_mod uas usb_storage scsi_mod hid_generic usbhid hid crc32c_intel mlx4_core ehci_pci uhci_hcd tg3 ehci_hcd ptp pps_core libphy usbcore usb_common thermal [ 176.892868] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.3.0-rc3-vanillaice #1 [ 176.892885] Hardware name: HP ProLiant DL320e Gen8, BIOS J05 11/09/2013 [ 176.892902] task: ffffffff81814540 ti: ffffffff81800000 task.ti: ffffffff81800000 [ 176.892919] RIP: 0010:[<ffffffff8144d1a6>] [<ffffffff8144d1a6>] __skb_checksum+0x2d6/0x2f0 [ 176.892942] RSP: 0018:ffff8802474038f8 EFLAGS: 00010286 [ 176.892955] RAX: 00000000ffff12f3 RBX: 00000000ffff12f3 RCX: 00000000ffff0ec6 [ 176.892972] RDX: ffff88022ce1d980 RSI: 00000000ffff12f3 RDI: ffff8800afed4400 [ 176.892988] RBP: 0000000000000000 R08: ffff880247403978 R09: 00000000ffff12f3 [ 176.893005] R10: ffff88022ce1d300 R11: 0000000000000002 R12: 0000000000000000 [ 176.893021] R13: 0000000000000000 R14: 00000000ffff12f3 R15: 0000000000000000 [ 176.893038] FS: 0000000000000000(0000) GS:ffff880247400000(0000) knlGS:0000000000000000 [ 176.893056] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 176.893070] CR2: 00007f42a19c0000 CR3: 000000000180d000 CR4: 00000000001406f0 [ 176.893086] Stack: [ 176.893092] 00000000b0ddb200 ffff880247403978 ffffffffffff12f3 ffffffff81814540 [ 176.893113] ffffffff81814540 ffffffff81814540 0000000000000000 ffff880000000000 [ 176.893134] 0000000000000246 ffff8800afed4400 0000000000000000 ffff88022ce1d300 [ 176.893155] Call Trace: [ 176.893162] <IRQ> [ 176.893169] [<ffffffff8144d1e2>] ? skb_checksum+0x22/0x30 [ 176.893185] [<ffffffff8144a940>] ? skb_push+0x40/0x40 [ 176.893198] [<ffffffff8144a5e0>] ? reqsk_fastopen_remove+0x150/0x150 [ 176.893214] [<ffffffff81535ed4>] ? udp6_ufo_fragment+0xb4/0x2e0 [ 176.893230] [<ffffffff8149ad74>] ? ip_finish_output2+0x134/0x350 [ 176.893245] [<ffffffff815358f2>] ? ipv6_gso_segment+0x112/0x2a0 [ 176.893260] [<ffffffff8144ac1e>] ? __kmalloc_reserve.isra.31+0x2e/0x80 [ 176.893276] [<ffffffff8145fe5e>] ? skb_mac_gso_segment+0x8e/0xe0 [ 176.893292] [<ffffffff814ded67>] ? gre_gso_segment+0x177/0x450 [ 176.893307] [<ffffffff814cf7d9>] ? inet_gso_segment+0x1d9/0x370 [ 176.893322] [<ffffffff81460600>] ? dev_hard_start_xmit+0x210/0x380 [ 176.893337] [<ffffffff8145fe5e>] ? skb_mac_gso_segment+0x8e/0xe0 [ 176.893352] [<ffffffff81460278>] ? validate_xmit_skb.isra.98.part.99+0x128/0x2a0 [ 176.893370] [<ffffffff814607a6>] ? validate_xmit_skb_list+0x36/0x50 [ 176.893953] [<ffffffff81481da2>] ? sch_direct_xmit+0x102/0x1e0 [ 176.894534] [<ffffffff81481f0e>] ? __qdisc_run+0x8e/0x1b0 [ 176.895115] [<ffffffff81460b4f>] ? __dev_queue_xmit+0x2bf/0x540 [ 176.895691] [<ffffffff8149ae9a>] ? ip_finish_output2+0x25a/0x350 [ 176.896264] [<ffffffff8149d0c8>] ? ip_output+0x68/0xd0 [ 176.896834] [<ffffffff81490e82>] ? nf_hook_slow+0x62/0xb0 [ 176.897389] [<ffffffff81499131>] ? ip_forward+0x391/0x480 [ 176.897927] [<ffffffff81498d10>] ? ip_frag_mem+0x40/0x40 [ 176.898446] [<ffffffff814978c7>] ? ip_rcv+0x277/0x3a0 [ 176.898948] [<ffffffff81496f90>] ? inet_del_offload+0x40/0x40 [ 176.899434] [<ffffffff8145e883>] ? __netif_receive_skb_core+0x843/0x9a0 [ 176.899909] [<ffffffff814dea33>] ? gre_gro_receive+0x1c3/0x380 [ 176.900383] [<ffffffff81535ac2>] ? tcp6_gro_complete+0x42/0x70 [ 176.900825] [<ffffffff8145ea5f>] ? netif_receive_skb_internal+0x1f/0x80 [ 176.901302] [<ffffffff8145f223>] ? dev_gro_receive+0x213/0x340 [ 176.901723] [<ffffffff8145f527>] ? napi_gro_receive+0x27/0xc0 [ 176.902140] [<ffffffffa051eaf0>] ? gro_cell_poll+0x50/0x90 [ip_tunnel] [ 176.902552] [<ffffffff8145eefa>] ? net_rx_action+0x20a/0x320 [ 176.902957] [<ffffffff810739d7>] ? __do_softirq+0x107/0x270 [ 176.903354] [<ffffffff81073c76>] ? irq_exit+0x86/0x90 [ 176.903744] [<ffffffff8155198f>] ? do_IRQ+0x4f/0xd0 [ 176.904132] [<ffffffff8154f642>] ? common_interrupt+0x82/0x82 [ 176.904516] <EOI> [ 176.904524] [<ffffffff81429788>] ? cpuidle_enter_state+0xe8/0x220 [ 176.905287] [<ffffffff81429763>] ? cpuidle_enter_state+0xc3/0x220 [ 176.905670] [<ffffffff810ab064>] ? cpu_startup_entry+0x284/0x340 [ 176.906048] [<ffffffff8192ff37>] ? start_kernel+0x472/0x47a [ 176.906422] [<ffffffff8192f120>] ? early_idt_handler_array+0x120/0x120 [ 176.906793] [<ffffffff8192f600>] ? x86_64_start_kernel+0x145/0x154 [ 176.907157] Code: 14 37 39 c2 7d 92 be 20 08 00 00 48 c7 c7 91 35 78 81 89 44 24 38 e8 da 23 c2 ff 8b 44 24 38 e9 74 ff ff ff 31 ed e9 9a fd ff ff <0f> 0b 89 4c 24 10 e9 50 ff ff ff 66 66 66 66 66 66 2e 0f 1f 84 [ 176.907990] RIP [<ffffffff8144d1a6>] __skb_checksum+0x2d6/0x2f0 [ 176.908412] RSP <ffff8802474038f8>
Dumped wrong ethtool output above. Issuing the following commands: ethtool -K eth2 rx off ethtool -K eth2 tx off ethtool -K eth2 gro off ethtool -K eth2 gso off ethtool -K eth2 tso off ethtool -K eth2 sg off ethtool -K eth2.305 gro off Result is like this one when crashing: Features for eth2: rx-checksumming: off tx-checksumming: off tx-checksum-ipv4: off tx-checksum-ip-generic: off [fixed] tx-checksum-ipv6: off tx-checksum-fcoe-crc: off [fixed] tx-checksum-sctp: off [fixed] scatter-gather: off tx-scatter-gather: off tx-scatter-gather-fraglist: off [fixed] tcp-segmentation-offload: off tx-tcp-segmentation: off tx-tcp-ecn-segmentation: off [fixed] tx-tcp6-segmentation: off udp-fragmentation-offload: off [fixed] generic-segmentation-offload: off generic-receive-offload: off large-receive-offload: off [fixed] rx-vlan-offload: on tx-vlan-offload: on ntuple-filters: off [fixed] receive-hashing: on highdma: on [fixed] rx-vlan-filter: on [fixed] vlan-challenged: off [fixed] tx-lockless: off [fixed] netns-local: off [fixed] tx-gso-robust: off [fixed] tx-fcoe-segmentation: off [fixed] tx-gre-segmentation: off [fixed] tx-ipip-segmentation: off [fixed] tx-sit-segmentation: off [fixed] tx-udp_tnl-segmentation: off [fixed] fcoe-mtu: off [fixed] tx-nocache-copy: off loopback: off rx-fcs: off [fixed] rx-all: off [fixed] tx-vlan-stag-hw-insert: off [fixed] rx-vlan-stag-hw-parse: on rx-vlan-stag-filter: on [fixed] l2-fwd-offload: off [fixed] busy-poll: on [fixed]