[255166.163658] BUG: kernel NULL pointer dereference, address: 0000000000000008
[255166.171112] #PF: supervisor read access in kernel mode
[255166.176735] #PF: error_code(0x0000) - not-present page
[255166.182366] PGD 0 P4D 0 
[255166.185389] Oops: 0000 [#1] SMP NOPTI
[255166.189551] CPU: 9 PID: 0 Comm: swapper/9 Kdump: loaded Tainted: G           OE     5.4.0-110-generic #124~18.04.1-Ubuntu
[255166.201317] Hardware name: Supermicro Super Server/X11SRM-F, BIOS 1.2b 04/29/2019
[255166.209605] RIP: 0010:rb_insert_color+0x17/0x190
[255166.215083] Code: 85 d2 75 eb 5d c3 31 c0 5d c3 66 0f 1f 84 00 00 00 00 00 55 48 8b 17 48 89 e5 48 85 d2 0f 84 4c 01 00 00 48 8b 02 a8 01 75 5e <48> 8b 48 08 49 89 c0 48 39 d1 74 54 48 85 c9 74 09 f6 01 01 0f 84
[255166.234838] RSP: 0018:ffffbcbc40330d50 EFLAGS: 00010046
[255166.240781] RAX: 0000000000000000 RBX: ffff9a07fc2bac98 RCX: ffff9a06d32c7098
[255166.248512] RDX: ffff9a06d32c7098 RSI: ffff9a0a19d56958 RDI: ffff9a07fc2bac98
[255166.256468] RBP: ffffbcbc40330d50 R08: ffff9a06aed14288 R09: ffffbcbc43d9f8e8
[255166.264464] R10: 0000000000000000 R11: ffffbcbc40330d39 R12: ffff9a0a19d56958
[255166.272453] R13: 0000000000000001 R14: 0000000000000000 R15: ffff9a07fc2bac98
[255166.280525] FS:  0000000000000000(0000) GS:ffff9a0a3fe40000(0000) knlGS:0000000000000000
[255166.289530] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[255166.295851] CR2: 0000000000000008 CR3: 0000001d45af0001 CR4: 00000000003606e0
[255166.303580] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[255166.311328] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[255166.319067] Call Trace:
[255166.322065]  <IRQ>
[255166.324626]  bfq_insert+0x5c/0x70 [bfq]
[255166.328998]  __bfq_deactivate_entity+0xe7/0x1b0 [bfq]
[255166.334598]  bfq_deactivate_entity+0x5d/0xd0 [bfq]
[255166.339934]  bfq_del_bfqq_busy+0xac/0x150 [bfq]
[255166.345000]  __bfq_bfqq_expire+0x64/0xd0 [bfq]
[255166.349971]  bfq_bfqq_expire+0x331/0x930 [bfq]
[255166.354937]  ? try_to_wake_up+0x235/0x5f0
[255166.359473]  ? bfq_dispatch_request+0xf70/0xf70 [bfq]
[255166.365045]  bfq_idle_slice_timer+0x6d/0xc0 [bfq]
[255166.370273]  __hrtimer_run_queues+0x10f/0x280
[255166.375143]  hrtimer_interrupt+0xe7/0x230
[255166.379672]  smp_apic_timer_interrupt+0x6f/0x130
[255166.384811]  apic_timer_interrupt+0xf/0x20
[255166.389408]  </IRQ>
[255166.392006] RIP: 0010:mwait_idle+0x84/0x1d0
[255166.396704] Code: c0 bb 01 00 48 89 d1 0f 01 c8 48 8b 00 a8 08 0f 85 46 01 00 00 e9 07 00 00 00 0f 00 2d a7 3a 52 00 31 c0 48 89 c1 fb 0f 01 c9 <65> 44 8b 25 e4 23 93 4c 0f 1f 44 00 00 eb 07 fb 66 0f 1f 44 00 00
[255166.416391] RSP: 0018:ffffbcbc40143e80 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
[255166.424482] RAX: 0000000000000000 RBX: 0000000000000009 RCX: 0000000000000000
[255166.432150] RDX: 0000000000000000 RSI: 0000000000000087 RDI: 0000000000000009
[255166.439788] RBP: ffffbcbc40143ea0 R08: 0000000000000000 R09: 000000000002f680
[255166.447427] R10: ffffbcbc40143e78 R11: 0000000000000000 R12: 0000000000000009
[255166.455066] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[255166.462711]  arch_cpu_idle+0x15/0x20
[255166.466785]  default_idle_call+0x23/0x30
[255166.471191]  do_idle+0x1bd/0x270
[255166.474891]  cpu_startup_entry+0x1d/0x20
[255166.479289]  start_secondary+0x166/0x1c0
[255166.483705]  secondary_startup_64+0xa4/0xb0
[255166.488354] Modules linked in: tcp_diag udp_diag inet_diag veth nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo br_netfilter bridge netconsole aufs overlay 8021q garp mrp stp llc bonding mlx5_core(OE) tls mlxfw(OE) ip6table_filter ip6_tables xt_nat xt_MASQUERADE xt_addrtype iptable_nat nf_nat xt_owner iptable_mangle iptable_raw xt_tcpmss xt_tcpudp xt_comment xt_multiport xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bpfilter nls_iso8859_1 intel_rapl_msr intel_rapl_common isst_if_common ast drm_vram_helper skx_edac nfit x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel crypto_simd cryptd glue_helper rapl intel_cstate ipmi_ssif ttm snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hda_core joydev input_leds drm_kms_helper snd_hwdep drm fb_sys_fops snd_pcm syscopyarea snd_timer sysfillrect snd sysimgblt ipmi_si soundcore ipmi_devintf intel_lpss_pci intel_lpss ipmi_msghandler ioatdma idma64
[255166.488379]  virt_dma mac_hid sch_fq_codel bfq ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid0 multipath linear mlx4_en(OE) mlx4_ib(OE) hid_generic usbhid hid raid1 igb mlx4_core(OE) i2c_algo_bit ahci mlx_compat(OE) dca libahci wmi
[255166.609642] CR2: 0000000000000008