19.10: "BUG: soft lockup - CPU stuck" related to IWL

Question

My machine occasionally hangs up for ~20 seconds soon after I log in (most likely when it tries to connect to Wifi, given the log below).

I found the following in my journalctl:

Mar 09 13:49:31 my-laptop kernel: [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=20389 end=20390) time 4674 us, min 763, max 767, scanline start 740, end 149
Mar 09 13:49:42 my-laptop kernel: watchdog: BUG: soft lockup - CPU#4 stuck for 24s! [kworker/4:0:3018]
Mar 09 13:49:42 my-laptop kernel: Modules linked in: rfcomm acpi_call(OE) xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c bpfilter br_netfilter bridge stp llc aufs cmac overlay bnep uvcvideo videobuf2_vmalloc btusb videobuf2_memops btrtl videobuf2_v4l2 btbcm btintel videobuf2_common videodev bluetooth mc ecdh_generic ecc nls_iso8859_1 sof_pci_dev snd_sof_intel_hda_common snd_sof_intel_hda snd_sof_intel_byt snd_sof_intel_ipc snd_sof snd_sof_xtensa_dsp snd_soc_skl snd_soc_hdac_hda snd_hda_ext_core snd_soc_skl_ipc snd_soc_sst_ipc snd_soc_sst_dsp snd_soc_acpi_intel_match snd_soc_acpi x86_pkg_temp_thermal mei_hdcp intel_powerclamp coretemp snd_hda_codec_hdmi snd_soc_core snd_hda_codec_conexant snd_hda_codec_generic intel_rapl_msr snd_compress ac97_bus kvm_intel snd_pcm_dmaengine kvm irqbypass snd_hda_intel snd_hda_codec snd_hda_core crct10dif_pclmul crc32_pclmul snd_hwdep snd_pcm
Mar 09 13:49:42 my-laptop kernel:  ghash_clmulni_intel thinkpad_acpi nvram i915 ledtrig_audio iwlmvm snd_seq_midi snd_seq_midi_event mac80211 drm_kms_helper snd_rawmidi libarc4 aesni_intel snd_seq aes_x86_64 crypto_simd drm cryptd glue_helper iwlwifi intel_cstate snd_seq_device i2c_algo_bit fb_sys_fops input_leds joydev intel_rapl_perf snd_timer intel_wmi_thunderbolt serio_raw mei_me syscopyarea sysfillrect ucsi_acpi snd wmi_bmof processor_thermal_device intel_rapl_common cfg80211 mei intel_soc_dts_iosf sysimgblt typec_ucsi intel_pch_thermal typec soundcore int3403_thermal int340x_thermal_zone int3400_thermal mac_hid acpi_pad acpi_thermal_rel sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 nvme psmouse i2c_i801 nvme_core sdhci_pci r8169 ahci cqhci realtek sdhci libahci wmi pinctrl_cannonlake video pinctrl_intel
Mar 09 13:49:42 my-laptop kernel: CPU: 4 PID: 3018 Comm: kworker/4:0 Tainted: G           OE     5.3.0-40-generic #32-Ubuntu
Mar 09 13:49:42 my-laptop kernel: Hardware name: LENOVO 20N80009AD/20N80009AD, BIOS R0YET32W (1.15 ) 06/10/2019
Mar 09 13:49:42 my-laptop kernel: Workqueue: events iwl_fw_error_dump_wk [iwlwifi]
Mar 09 13:49:42 my-laptop kernel: RIP: 0010:_raw_spin_unlock_irqrestore+0x15/0x20
Mar 09 13:49:42 my-laptop kernel: Code: 00 e9 78 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 c6 07 00 0f 1f 40 00 48 89 f7 57 9d <0f> 1f 44 00 00 5d c3 0f 1f 40 00 0f 1f 44 00 00 55 49 89 f8 b8 00
Mar 09 13:49:42 my-laptop kernel: RSP: 0018:ffff9c9741bd7cb8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
Mar 09 13:49:42 my-laptop kernel: RAX: ffffffffc05d1620 RBX: ffff895edffa0018 RCX: 0000000000000003
Mar 09 13:49:42 my-laptop kernel: RDX: 0000000008040005 RSI: 0000000000000246 RDI: 0000000000000246
Mar 09 13:49:42 my-laptop kernel: RBP: ffff9c9741bd7cb8 R08: 0000000000003a98 R09: 0000000000000011
Mar 09 13:49:42 my-laptop kernel: R10: ffffbe7357cef588 R11: 0000000000005328 R12: 00000000fffffff7
Mar 09 13:49:42 my-laptop kernel: R13: ffff9c9741bd7cf0 R14: 0000000000400000 R15: ffff895ed8dd2cb8
Mar 09 13:49:42 my-laptop kernel: FS:  0000000000000000(0000) GS:ffff895ee6300000(0000) knlGS:0000000000000000
Mar 09 13:49:42 my-laptop kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Mar 09 13:49:42 my-laptop kernel: CR2: 00007f4265a5cfc8 CR3: 000000065d486001 CR4: 00000000003606e0
Mar 09 13:49:42 my-laptop kernel: Call Trace:
Mar 09 13:49:42 my-laptop kernel:  iwl_trans_pcie_release_nic_access+0x61/0x70 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  iwl_trans_pcie_read_mem+0x94/0xc0 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  iwl_fw_dump_mem.isra.0.part.0+0x50/0x90 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  iwl_fw_error_dump_file.isra.0+0x436/0xf80 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  iwl_fw_dbg_collect_sync+0x35c/0x910 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  ? __switch_to_asm+0x40/0x70
Mar 09 13:49:42 my-laptop kernel:  ? __switch_to+0x7f/0x470
Mar 09 13:49:42 my-laptop kernel:  ? __switch_to_asm+0x40/0x70
Mar 09 13:49:42 my-laptop kernel:  iwl_fw_error_dump_wk+0x59/0x80 [iwlwifi]
Mar 09 13:49:42 my-laptop kernel:  process_one_work+0x1db/0x380
Mar 09 13:49:42 my-laptop kernel:  worker_thread+0x4d/0x400
Mar 09 13:49:42 my-laptop kernel:  kthread+0x104/0x140
Mar 09 13:49:42 my-laptop kernel:  ? process_one_work+0x380/0x380
Mar 09 13:49:42 my-laptop kernel:  ? kthread_park+0x80/0x80
Mar 09 13:49:42 my-laptop kernel:  ret_from_fork+0x35/0x40
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:79
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:64
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:70
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 226:0
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:71
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:67
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:68
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:69
Mar 09 13:49:42 my-laptop /usr/lib/gdm3/gdm-x-session[2412]: (II) systemd-logind: got pause for 13:66
Mar 09 13:49:42 my-laptop systemd[1]: Started Getty on tty3.
Mar 09 13:49:42 my-laptop kernel: iwlwifi 0000:05:00.0: Scan failed! ret -5
Mar 09 13:49:42 my-laptop wpa_supplicant[1094]: wlp5s0: CTRL-EVENT-SCAN-FAILED ret=-5
Mar 09 13:49:42 my-laptop geoclue[2694]: WiFi scan failed
Mar 09 13:49:42 my-laptop kernel: iwlwifi 0000:05:00.0: Failing on timeout while stopping DMA channel 8 [0xa5a5a5a2]
Mar 09 13:49:42 my-laptop kernel: iwlwifi 0000:05:00.0: Applying debug destination EXTERNAL_DRAM
Mar 09 13:49:42 my-laptop kernel: iwlwifi 0000:05:00.0: Applying debug destination EXTERNAL_DRAM
Mar 09 13:49:43 my-laptop kernel: iwlwifi 0000:05:00.0: FW already configured (0) - re-configuring
Mar 09 13:49:43 my-laptop wpa_supplicant[1094]: wlp5s0: CTRL-EVENT-REGDOM-CHANGE init=DRIVER type=WORLD
Mar 09 13:49:43 my-laptop wpa_supplicant[1094]: wlp5s0: CTRL-EVENT-SIGNAL-CHANGE above=1 signal=-60 noise=9999 txrate=300000

As requested, the output of dmesg | grep iwl.

Some more info:

$ uname -a
Linux my-laptop 5.3.0-40-generic #32-Ubuntu SMP Fri Jan 31 20:24:34 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux`

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 19.10
Release:    19.10
Codename:   eoan

$ lspci
00:00.0 Host bridge: Intel Corporation Device 3e34 (rev 0b)
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (Whiskey Lake)
00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 0b)
00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th Gen Core Processor Gaussian Mixture Model
00:12.0 Signal processing controller: Intel Corporation Cannon Point-LP Thermal Controller (rev 30)
00:14.0 USB controller: Intel Corporation Cannon Point-LP USB 3.1 xHCI Controller (rev 30)
00:14.2 RAM memory: Intel Corporation Cannon Point-LP Shared SRAM (rev 30)
00:16.0 Communication controller: Intel Corporation Cannon Point-LP MEI Controller #1 (rev 30)
00:17.0 SATA controller: Intel Corporation Cannon Point-LP SATA Controller [AHCI Mode] (rev 30)
00:1c.0 PCI bridge: Intel Corporation Cannon Point-LP PCI Express Root Port #1 (rev f0)
00:1d.0 PCI bridge: Intel Corporation Cannon Point-LP PCI Express Root Port #9 (rev f0)
00:1d.2 PCI bridge: Intel Corporation Device 9db2 (rev f0)
00:1d.4 PCI bridge: Intel Corporation Cannon Point-LP PCI Express Root Port #13 (rev f0)
00:1f.0 ISA bridge: Intel Corporation Cannon Point-LP LPC Controller (rev 30)
00:1f.3 Audio device: Intel Corporation Cannon Point-LP High Definition Audio Controller (rev 30)
00:1f.4 SMBus: Intel Corporation Cannon Point-LP SMBus Controller (rev 30)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Point-LP SPI Controller (rev 30)
02:00.0 SD Host controller: O2 Micro, Inc. SD/MMC Card Reader Controller (rev 01)
04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10)
05:00.0 Network controller: Intel Corporation Wireless-AC 9260 (rev 29)
07:00.0 Non-Volatile memory controller: Kingston Technology Company, Inc. Device 2263 (rev 03)