I've got this on two different machines:
[ 24.405015] divide error: 0000 [#1] SMP
[ 24.405403] Modules linked in: nf_log_ipv6 nf_log_common xt_LOG xt_u32 ip6t_REJECT nf_reject_ipv6 xt_conntrack ip6table_nat
nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_filter ip6_tables xt_tcpudp ipt_REJECT nf_reject_ipv4 xt_multiport xt_mark xt_owner
iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_filter ip_tables x_tables 8021q garp mrp stp llc nfsd
auth_rpcgss nfs_acl nfs lockd grace sunrpc fscache cls_u32 sch_fq sch_prio intel_rapl iosf_mbi sb_edac edac_core x86_pkg_temp_thermal
intel_powerclamp ipmi_ssif coretemp ast kvm_intel ttm kvm drm_kms_helper drm fb_sys_fops syscopyarea sysfillrect sysimgblt irqbypass lpc_ich
mei_me ipmi_msghandler mei ghash_clmulni_intel wmi joydev input_leds mac_hid shpchp acpi_pad tcp_nv xfs raid456 async_raid6_recov async_memcpy
[ 24.409249] async_pq async_xor async_tx xor raid10 raid6_pq igb libcrc32c i2c_algo_bit isci dca raid1 ptp libsas pps_core raid0
scsi_transport_sas multipath fjes linear [last unloaded: ipmi_devintf]
[ 24.410898] CPU: 0 PID: 2915 Comm: python2 Not tainted 4.9.59-14 #1
[ 24.411766] Hardware name: AIC 1S-HV26-08/MB-DPSB04-06, BIOS IVYBV060
10/21/2015
[ 24.412677] task: ffff881fca8e8000 task.stack: ffffc9001c748000
[ 24.413615] RIP: 0010:tcpnv_acked (net/ipv4/tcp_nv.c:183) tcp_nv
[ 24.414327] RSP: 0018:ffffc9001c74bb30 EFLAGS: 00010206
[ 24.414351] RAX: 000000000f424000 RBX: ffff883fe76507c0 RCX: 0000000000000000
[ 24.416399] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff883fe76507c0
[ 24.417510] RBP: ffffc9001c74bb58 R08: 0000000000000001 R09: 0000000000000000
[ 24.418640] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffef2aa
[ 24.419787] R13: 00000000d7d9d925 R14: 00000000d7d9d905 R15: 0000000000000000
[ 24.420653] FS: 00007f148f406700(0000) GS:ffff881fffa00000(0000)
knlGS:0000000000000000
[ 24.421855] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 24.423074] CR2: 00007f148f4de000 CR3: 0000001fe60f8000 CR4: 00000000001406f0
[ 24.424332] Call Trace:
[ 24.425593] Code: 48 63 c9 48 0f af c1 49 8d 0c 00 44 8b 87 d8 04 00 00 48 c1 e9 08 89 8f d4 04 00 00 8b 46 08 48 69 c0 00 12 7a 00 31 d2
6b f1 64 <48> f7 f6 3b 87 e0 04 00 00 76 06 89 87 e0 04 00 00 0f b6 87 d1
All code
========
0: 48 63 c9 movslq %ecx,%rcx
3: 48 0f af c1 imul %rcx,%rax
7: 49 8d 0c 00 lea (%r8,%rax,1),%rcx
b: 44 8b 87 d8 04 00 00 mov 0x4d8(%rdi),%r8d
12: 48 c1 e9 08 shr $0x8,%rcx
16: 89 8f d4 04 00 00 mov %ecx,0x4d4(%rdi)
1c: 8b 46 08 mov 0x8(%rsi),%eax
1f: 48 69 c0 00 12 7a 00 imul $0x7a1200,%rax,%rax
26: 31 d2 xor %edx,%edx
28: 6b f1 64 imul $0x64,%ecx,%esi
2b:* 48 f7 f6 div %rsi <-- trapping instruction
2e: 3b 87 e0 04 00 00 cmp 0x4e0(%rdi),%eax
34: 76 06 jbe 0x3c
36: 89 87 e0 04 00 00 mov %eax,0x4e0(%rdi)
3c: 0f .byte 0xf
3d: b6 87 mov $0x87,%dh
3f: d1 .byte 0xd1
// At entry tcpnv_acked() checks only for negative rtt_us
// Probably it's ok to check here <= 0 ?
/* Some calls are for duplicates without timetamps */
if (sample->rtt_us < 0)
return;
// <cut>
/* Calculate moving average of RTT */
if (nv_rtt_factor > 0) {
if (ca->nv_last_rtt > 0) {
avg_rtt = (((u64)sample->rtt_us) * nv_rtt_factor +
((u64)ca->nv_last_rtt)
* (256 - nv_rtt_factor)) >> 8;
// This should be positive
} else {
avg_rtt = sample->rtt_us;
// Here coule be zero
ca->nv_min_rtt = avg_rtt << 1;
}
ca->nv_last_rtt = avg_rtt;
} else {
avg_rtt = sample->rtt_us;
}
/* rate in 100's bits per second */
rate64 = ((u64)sample->in_flight) * 8000000;
rate = (u32)div64_u64(rate64, (u64)(avg_rtt * 100));
// Also cast to u64 should be done before multipying by 100: (u64)(0x80000000 *
100) == 0
