Ubuntu hangs and becomes unresponsive until reset

Question

Update Sep 8, 2022

I'm confident that the issue was with the BIOS. After it has been reflashed with an external programmer, I have seen no issues since. I'm still not 100% sure - only the time will show. It's mindblowing to think that hunting OS issues down takes years.

---

Original description

I experience quite annoying behavior on my Ubuntu 20.04. Every few days, the system becomes suddenly unresponsive until I hit the reset button (raising elephants is so utterly boring also helps). And I cannot track the issue down. Here is the /var/log/syslog at the crash time:

Oct 19 13:09:31 ubu dbus-daemon[845]: [system] Activating via systemd: service name='org.bluez' unit='dbus-org.bluez.service' requested by ':1.270' (ui
d=1000 pid=31899 comm="/opt/google/chrome/chrome --enable-crashpad https:" 
label="snap.pycharm-community.pycharm-community (complain)")
Oct 19 13:09:31 ubu systemd[1]: Condition check resulted in Bluetooth service being skipped.
Oct 19 13:09:51 ubu kernel: [16648.749845] ------------[ cut here ]------------
Oct 19 13:09:51 ubu kernel: [16648.749849] NETDEV WATCHDOG: enp3s0 (r8169): transmit queue 0 timed out
Oct 19 13:09:51 ubu kernel: [16648.749869] WARNING: CPU: 2 PID: 0 at net/sched/sch_generic.c:467 dev_watchdog+0x24f/0x260
Oct 19 13:09:51 ubu kernel: [16648.749874] Modules linked in: nf_conntrack_netlink xfrm_user xfrm_algo xt_addrtype aufs xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables libcrc32c nfnetlink bpfilter pktcdvd nvidia_uvm(POE) intel_powerclamp coretemp kvm_intel nvidia_drm(POE) nvidia_modeset(POE) kvm snd_hda_codec_via snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi rt2800usb snd_hda_intel rt2x00usb snd_intel_dspcfg rt2800lib soundwire_intel rt2x00lib soundwire_generic_allocation soundwire_cadence snd_hda_codec mac80211 snd_hda_core uvcvideo videobuf2_vmalloc soundwire_bus intel_cstate snd_usb_audio videobuf2_memops videobuf2_v4l2 snd_soc_core snd_usbmidi_lib snd_hwdep snd_compress videobuf2_common ac97_bus videodev snd_pcm_dmaengine mc cfg80211 snd_pcm cp210x nvidia(POE) usbserial input_leds snd_seq_midi libarc4 joydev serio_raw i7core_edac snd_seq_midi_event snd_rawmidi
Oct 19 13:09:51 ubu kernel: [16648.749922]  snd_seq snd_seq_device snd_timer snd drm_kms_helper cec asus_atk0110 rc_core fb_sys_fops syscopyarea soundcore sysfillrect mac_hid sysimgblt sch_fq_codel overlay iptable_filter ip6table_filter ip6_tables br_netfilter bridge stp llc arp_tables msr parport_pc ppdev lp parport drm ip_tables x_tables autofs4 hid_generic usbhid hid gpio_ich psmouse i2c_i801 i2c_smbus firewire_ohci firewire_core crc_itu_t r8169 lpc_ich realtek xhci_pci xhci_pci_renesas ahci libahci
Oct 19 13:09:51 ubu kernel: [16648.749953] CPU: 2 PID: 0 Comm: swapper/2 Tainted: P          IOE     5.11.0-37-generic #41~20.04.2-Ubuntu
Oct 19 13:09:51 ubu kernel: [16648.749956] Hardware name: System manufacturer System Product Name/P7P55D-E, BIOS 1601    06/26/2012
Oct 19 13:09:51 ubu kernel: [16648.749957] RIP: 0010:dev_watchdog+0x24f/0x260
Oct 19 13:09:51 ubu kernel: [16648.749959] Code: 07 78 fd ff eb ab 4c 89 ff c6 05 b2 2d ee 00 01 e8 26 3c fa ff 44 89 e9 4c 89 fe 48 c7 c7 f8 3f 89 a6 48 89 c2 e8 4f 56 16 00 <0f> 0b eb 8c 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 66 66 66 90
Oct 19 13:09:51 ubu kernel: [16648.749961] RSP: 0018:ffffaa5280180e88 EFLAGS: 00010282
Oct 19 13:09:51 ubu kernel: [16648.749963] RAX: 0000000000000000 RBX: ffff9d1f826f0400 RCX: 0000000000000027
Oct 19 13:09:51 ubu kernel: [16648.749964] RDX: 0000000000000027 RSI: 00000000ffffdfff RDI: ffff9d2097a98ac8
Oct 19 13:09:51 ubu kernel: [16648.749965] RBP: ffffaa5280180eb8 R08: ffff9d2097a98ac0 R09: ffffaa5280180c48
Oct 19 13:09:51 ubu kernel: [16648.749966] R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001
Oct 19 13:09:51 ubu kernel: [16648.749967] R13: 0000000000000000 R14: ffff9d1f8d80c4c0 R15: ffff9d1f8d80c000
Oct 19 13:09:51 ubu kernel: [16648.749968] FS:  0000000000000000(0000) GS:ffff9d2097a80000(0000) knlGS:0000000000000000
Oct 19 13:09:51 ubu kernel: [16648.749970] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Oct 19 13:09:51 ubu kernel: [16648.749971] CR2: 000002f600039040 CR3: 0000000145c10000 CR4: 00000000000006e0
Oct 19 13:09:51 ubu kernel: [16648.749973] Call Trace:
Oct 19 13:09:51 ubu kernel: [16648.749974]  <IRQ>
Oct 19 13:09:51 ubu kernel: [16648.749976]  ? pfifo_fast_enqueue+0x150/0x150
Oct 19 13:09:51 ubu kernel: [16648.749979]  call_timer_fn+0x2e/0x100
Oct 19 13:09:51 ubu kernel: [16648.749982]  __run_timers.part.0+0x1e0/0x250
Oct 19 13:09:51 ubu kernel: [16648.749985]  ? hpet_msi_interrupt_handler+0x1d/0x30
Oct 19 13:09:51 ubu kernel: [16648.749988]  run_timer_softirq+0x2a/0x50
Oct 19 13:09:51 ubu kernel: [16648.749990]  __do_softirq+0xe0/0x29b
Oct 19 13:09:51 ubu kernel: [16648.749995]  asm_call_irq_on_stack+0x12/0x20
Oct 19 13:09:51 ubu kernel: [16648.749997]  </IRQ>
Oct 19 13:09:51 ubu kernel: [16648.749998]  do_softirq_own_stack+0x3d/0x50
Oct 19 13:09:51 ubu kernel: [16648.750001]  irq_exit_rcu+0xa4/0xb0
Oct 19 13:09:51 ubu kernel: [16648.750004]  common_interrupt+0x7d/0x150
Oct 19 13:09:51 ubu kernel: [16648.750007]  asm_common_interrupt+0x1e/0x40
Oct 19 13:09:51 ubu kernel: [16648.750009] RIP: 0010:cpuidle_enter_state+0xdc/0x350
Oct 19 13:09:51 ubu kernel: [16648.750012] Code: 66 90 31 ff e8 d5 b3 77 ff 80 7d d7 00 74 17 9c 58 66 66 90 66 90 f6 c4 02 0f 85 52 02 00 00 31 ff e8 68 5d 7e ff fb 66 66 90 <66> 66 90 45 85 ff 0f 88 e5 00 00 00 49 63 c7 4c 2b 75 c8 48 8d 14
Oct 19 13:09:51 ubu kernel: [16648.750013] RSP: 0018:ffffaa52800a7e48 EFLAGS: 00000246
Oct 19 13:09:51 ubu kernel: [16648.750015] RAX: 0000000000000000 RBX: 0000000000000004 RCX: 000000000000001f
Oct 19 13:09:51 ubu kernel: [16648.750016] RDX: ffff9d1f80134640 RSI: 0000000025f03b35 RDI: 0000000000000000
Oct 19 13:09:51 ubu kernel: [16648.750017] RBP: ffffaa52800a7e80 R08: 00000f2456d1678e R09: 0000000000000001
Oct 19 13:09:51 ubu kernel: [16648.750018] R10: ffff9d2097aaaee4 R11: ffff9d2097aaaec4 R12: ffff9d2097ab7100
Oct 19 13:09:51 ubu kernel: [16648.750019] R13: ffffffffa6c4d8e0 R14: 00000f2456d1678e R15: 0000000000000004
Oct 19 13:09:51 ubu kernel: [16648.750022]  ? cpuidle_enter_state+0xd8/0x350
Oct 19 13:09:51 ubu kernel: [16648.750024]  cpuidle_enter+0x2e/0x40
Oct 19 13:09:51 ubu kernel: [16648.750026]  call_cpuidle+0x23/0x40
Oct 19 13:09:51 ubu kernel: [16648.750028]  do_idle+0x1df/0x260
Oct 19 13:09:51 ubu kernel: [16648.750030]  cpu_startup_entry+0x20/0x30
Oct 19 13:09:51 ubu kernel: [16648.750031]  start_secondary+0x11f/0x160
Oct 19 13:09:51 ubu kernel: [16648.750034]  secondary_startup_64_no_verify+0xc2/0xcb
Oct 19 13:09:51 ubu kernel: [16648.750037] ---[ end trace 010da4fe0ea94408 ]---
^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
<repeated>

There are some call traces but they don't make any sense to me.

The issue often occurs when I'm opening Chrome with Python+webbrowser module, though I'm not sure if that is the only reason. In particular, I recall that I had kernel crashes several times in other scenarios without Python involved. I don't trust my memory anymore, and I haven't noted it down. Comment deleted.

Why does it happen and how to fix it?

---

Update 1.

$ free
              total        used        free      shared  buff/cache   available
Mem:        8146032     5994208      213836      256784     1937988     1610020
Swap:       4881404     1181440     3699964

---

Update 2.

$ ls -al /var/crash/
total 12
drwxrwsrwt  2 root     whoopsie 4096 жов 15 18:14 .
drwxr-xr-x 15 root     root     4096 лип 22 10:03 ..
-rw-r--r--  1 kernoops whoopsie 2869 жов 15 18:14 linux-image-5.11.0-37-generic.209089.crash

$ cat /var/crash/linux-image-5.11.0-37-generic.209089.crash
ProblemType: KernelOops
Annotation: Your system might become unstable now and might need to be restarted.
Date: Fri Oct 15 18:14:19 2021
Failure: oops
OopsText:
 watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [kworker/3:1:4185]
 Modules linked in: nf_conntrack_netlink xfrm_user xfrm_algo xt_addrtype aufs xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables libcrc32c nfnetlink bpfilter pktcdvd nvidia_uvm(POE) nvidia_drm(POE) nvidia_modeset(POE) intel_powerclamp snd_hda_codec_via snd_hda_codec_generic ledtrig_audio coretemp snd_hda_codec_hdmi kvm_intel snd_hda_intel snd_intel_dspcfg rt2800usb soundwire_intel rt2x00usb soundwire_generic_allocation rt2800lib soundwire_cadence rt2x00lib kvm nvidia(POE) snd_hda_codec mac80211 intel_cstate snd_hda_core snd_usb_audio snd_usbmidi_lib soundwire_bus snd_hwdep snd_soc_core uvcvideo cfg80211 snd_compress serio_raw ac97_bus i7core_edac snd_pcm_dmaengine snd_seq_midi videobuf2_vmalloc snd_seq_midi_event videobuf2_memops videobuf2_v4l2 libarc4 snd_rawmidi videobuf2_common snd_pcm joydev videodev input_leds snd_seq mc
  snd_seq_device drm_kms_helper cec rc_core fb_sys_fops syscopyarea sysfillrect sysimgblt snd_timer snd soundcore asus_atk0110 mac_hid sch_fq_codel overlay iptable_filter ip6table_filter ip6_tables br_netfilter bridge stp llc arp_tables msr parport_pc ppdev lp parport drm ip_tables x_tables autofs4 hid_generic usbhid hid gpio_ich firewire_ohci firewire_core psmouse i2c_i801 i2c_smbus lpc_ich crc_itu_t r8169 xhci_pci realtek ahci xhci_pci_renesas libahci
 CPU: 3 PID: 4185 Comm: kworker/3:1 Tainted: P      D W IOE     5.11.0-37-generic #41~20.04.2-Ubuntu
 Hardware name: System manufacturer System Product Name/P7P55D-E, BIOS 1601    06/26/2012
 Workqueue: rcu_gp wait_rcu_exp_gp
 RIP: 0010:smp_call_function_single+0xa0/0x120
 Code: fc ab 7a a9 00 01 ff 00 0f 85 83 00 00 00 85 c9 75 42 48 c7 c6 40 d2 02 00 65 48 03 35 81 96 ab 7a 8b 46 08 a8 01 74 09 f3 90 <8b> 46 08 a8 01 75 f7 83 4e 08 01 4c 89 46 10 48 89 56 18 e8 b8 fe
 RSP: 0018:ffffb8d1c8803d60 EFLAGS: 00000202
 RAX: 0000000000000001 RBX: ffffffff86b553f8 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: ffff9fd457aed240 RDI: 0000000000000002
 RBP: ffffb8d1c8803db8 R08: ffffffff8552d5d0 R09: 0000000000000002
 R10: ffff9fd40de4fd2c R11: 0000000000000000 R12: 000000000000000a
 R13: 0000000000000004 R14: ffff9fd457aad080 R15: ffffffff86b55240
 FS:  0000000000000000(0000) GS:ffff9fd457ac0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000385a095fb000 CR3: 000000010b0a0000 CR4: 00000000000006e0
 Call Trace:
 
Package: linux-image-5.11.0-37-generic 5.11.0-37.41~20.04.2
SourcePackage: linux
Tags: kernel-oops
Uname: Linux 5.11.0-37-generic x86_64

This crash corresponds to the following lines in /var/log/syslog. I've uploaded the crash log crash-Oct15.txt to dropbox because it's too long - this time I got multiple kernel crashes happened at once one after the other.

---

Update 3.

I have another crash without the network driver involved. This time, I had peculiar behavior: I could move the mouse over the screen though I couldn't click it, and other peripherals didn't respond either.

Oct 20 12:12:45 ubu dbus-daemon[835]: [system] Activating via systemd: service name='org.bluez' unit='dbus-org.bluez.service' requ
ested by ':1.294' (uid=1000 pid=73247 comm="/opt/google/chrome/chrome --enable-crashpad https:" label="snap.pycharm-community.pych
arm-community (complain)")
Oct 20 12:12:45 ubu systemd[1]: Condition check resulted in Bluetooth service being skipped.
Oct 20 12:13:12 ubu kernel: [11688.108050] watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [chrome:73888]
Oct 20 12:13:12 ubu kernel: [11688.108059] Modules linked in: btrfs blake2b_generic xor raid6_pq ufs qnx4 hfsplus hfs minix ntfs m
sdos jfs xfs cpuid nf_conntrack_netlink xfrm_user xfrm_algo xt_addrtype aufs xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_
reject_ipv4 xt_tcpudp ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf
_tables libcrc32c nfnetlink bpfilter pktcdvd nvidia_uvm(POE) nvidia_drm(POE) nvidia_modeset(POE) snd_hda_codec_via snd_hda_codec_g
eneric ledtrig_audio snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg soundwire_intel soundwire_generic_allocation soundwire_cade
nce snd_hda_codec snd_hda_core soundwire_bus nvidia(POE) rt2800usb snd_soc_core rt2x00usb snd_usb_audio intel_powerclamp snd_compr
ess coretemp rt2800lib snd_usbmidi_lib ac97_bus snd_pcm_dmaengine snd_hwdep snd_seq_midi kvm_intel snd_seq_midi_event rt2x00lib sn
d_seq snd_rawmidi kvm mac80211 snd_pcm uvcvideo videobuf2_vmalloc videobuf2_memops intel_cstate videobuf2_v4l2
Oct 20 12:13:12 ubu kernel: [11688.108111]  snd_seq_device serio_raw videobuf2_common i7core_edac videodev snd_timer mc cfg80211 s
nd drm_kms_helper libarc4 input_leds cec rc_core joydev fb_sys_fops syscopyarea sysfillrect sysimgblt soundcore asus_atk0110 mac_h
id sch_fq_codel overlay iptable_filter ip6table_filter ip6_tables br_netfilter bridge stp llc arp_tables msr parport_pc ppdev lp d
rm parport ip_tables x_tables autofs4 hid_generic usbhid hid gpio_ich psmouse r8169 firewire_ohci realtek lpc_ich firewire_core i2
c_i801 ahci crc_itu_t i2c_smbus xhci_pci xhci_pci_renesas libahci
Oct 20 12:13:12 ubu kernel: [11688.108147] CPU: 3 PID: 73888 Comm: chrome Tainted: P          IOE     5.11.0-37-generic #41~20.04.
2-Ubuntu
Oct 20 12:13:12 ubu kernel: [11688.108149] Hardware name: System manufacturer System Product Name/P7P55D-E, BIOS 1601    06/26/201
2
Oct 20 12:13:12 ubu kernel: [11688.108151] RIP: 0010:_nv028953rm+0x2c/0x90 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.108555] Code: ec 08 48 85 ff 74 5f 48 8b 57 10 31 c0 48 85 d2 74 2e 48 8b 4f 08 31 c0 48 85 c9 74 0d 48 63 41 14 48 89 d6 48 29 c6 48 89 f0 <48> 3b 57 18 48 89 07 74 1b 48 8b 42 08 48 89 47 10 b8 01 00 00 00
Oct 20 12:13:12 ubu kernel: [11688.108557] RSP: 0018:ffffad410b6cfb90 EFLAGS: 00000297
Oct 20 12:13:12 ubu kernel: [11688.108558] RAX: ffffef8a00c1e1be RBX: ffff9d583645b430 RCX: ffff9d588939f978
Oct 20 12:13:12 ubu kernel: [11688.108560] RDX: ffffef8a00c1d148 RSI: ffffef8a00c1e1be RDI: ffff9d57b08e5d20
Oct 20 12:13:12 ubu kernel: [11688.108561] RBP: ffff9d57b08e5d20 R08: 0000000000000020 R09: ffff9d57b08e5d28
Oct 20 12:13:12 ubu kernel: [11688.108562] R10: 0000000000000000 R11: 0000000000000001 R12: ffff9d58a82eb798
Oct 20 12:13:12 ubu kernel: [11688.108563] R13: ffffef8a00051036 R14: ffff9d57b08e5d98 R15: ffff9d583645b430
Oct 20 12:13:12 ubu kernel: [11688.108564] FS:  00007f12c37d6540(0000) GS:ffff9d5997ac0000(0000) knlGS:0000000000000000
Oct 20 12:13:12 ubu kernel: [11688.108566] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Oct 20 12:13:12 ubu kernel: [11688.108567] CR2: 00007fb4731dbf80 CR3: 00000001b0030000 CR4: 00000000000006e0
Oct 20 12:13:12 ubu kernel: [11688.108569] Call Trace:
Oct 20 12:13:12 ubu kernel: [11688.108572]  ? _nv035831rm+0xa8/0xe0 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.108897]  ? _nv014653rm+0x2ee/0x770 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.109223]  ? _nv037672rm+0xb3/0x150 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.109549]  ? _nv037671rm+0x297/0x4e0 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.109874]  ? _nv037666rm+0x60/0x70 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.110199]  ? _nv037667rm+0x7b/0xb0 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.110525]  ? _nv036043rm+0x40/0xe0 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.110774]  ? _nv000699rm+0x68/0x80 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.111073]  ? rm_cleanup_file_private+0xea/0x160 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.111372]  ? nvidia_close+0x15f/0x2e0 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.111564]  ? security_file_free+0x54/0x60
Oct 20 12:13:12 ubu kernel: [11688.111570]  ? nvidia_frontend_close+0x2f/0x50 [nvidia]
Oct 20 12:13:12 ubu kernel: [11688.111767]  ? __fput+0x9f/0x250
Oct 20 12:13:12 ubu kernel: [11688.111771]  ? ____fput+0xe/0x10
Oct 20 12:13:12 ubu kernel: [11688.111773]  ? task_work_run+0x70/0xb0
Oct 20 12:13:12 ubu kernel: [11688.111776]  ? do_exit+0x389/0xaf0
Oct 20 12:13:12 ubu kernel: [11688.111779]  ? do_group_exit+0x43/0xa0
Oct 20 12:13:12 ubu kernel: [11688.111782]  ? __x64_sys_exit_group+0x18/0x20
Oct 20 12:13:12 ubu kernel: [11688.111784]  ? do_syscall_64+0x38/0x90
Oct 20 12:13:12 ubu kernel: [11688.111786]  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
Oct 20 12:13:18 ubu kernel: [11693.732644] sysrq: This sysrq operation is disabled.
Oct 20 12:13:18 ubu gnome-shell[3765]: [1020/121318.631417:WARNING:exception_snapshot_linux.cc(427)] Unhandled signal -1
Oct 20 12:13:18 ubu gnome-shell[3765]: [1020/121318.631782:ERROR:file_io_posix.cc(144)] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq: No such file or directory (2)
Oct 20 12:13:18 ubu gnome-shell[3765]: [1020/121318.631807:ERROR:file_io_posix.cc(144)] open /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq: No such file or directory (2)
Oct 20 12:13:19 ubu kernel: [11694.196698] sysrq: This sysrq operation is disabled.
Oct 20 12:13:19 ubu kernel: [11694.908690] sysrq: This sysrq operation is disabled.
Oct 20 12:13:20 ubu kernel: [11695.228730] sysrq: Emergency Sync
Oct 20 12:13:20 ubu kernel: [11695.338249] Emergency Sync complete
Oct 20 12:13:20 ubu kernel: [11695.636742] sysrq: Emergency Remount R/O

---

Update 4 (Nov 06, 2021)

I had another crash today. I've uploaded the log on Dropbox: https://www.dropbox.com/s/xsceadfvqie2rjs/crash-Nov16.log?dl=1

Seems like I'm getting this kind of crash only when I open a Chrome via Python webbrowser package (but not immediately and sometimes without a problem).

---

Update 5

I have Nvidia GTX 980, driver 470.42.01.

The BIOS version is P7P55D-E BIOS 1601, the latest available from the manufacturer (2013 year).

---

Update 6

I've hit another crash of the same type while running a Python program (opening a browser with the webbrowser library). I've updated every PC component save for two SSDs that I've left unchanged.

Syslog file: https://www.dropbox.com/s/rz2331idgyt7un0/crash-Jan22.txt?dl=1

---

Update 7.

Had another crash today. This time I was opening a link in a Chrome browser from a telegram. No Python involved. No webbrowser Python lib respectively.

Syslog: https://www.dropbox.com/s/z2ug91s3kalce04/crash_Jan29.txt?dl=1

Answer 1

You've got a very old computer, but I suspect that this might fix your problem, based on the information provided in your question...

MSI/MSIX interrupts were enabled for certain ethernet cards in Ubuntu 20.xx. This can cause intermittent ethernet operation. Here's a patch to fix it. Follow the embedded instructions to install.

#!/bin/sh

# https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1779817

# filename: r8169_disable_msi

# Drop it in /etc/initramfs-tools/scripts/init-top and chmod a+x it. Add 'r8169_disable_msi'
# to your kernel command line (/etc/default/grub, GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
# usually.) 

# sudo -H gedit /etc/default/grub # to edit the file

# Remember to update-initramfs and update-grub as necessary.

# sudo update-initramfs -c -k $(uname -r)
# sudo update-grub
# reboot

# For the moment it disables MSI on everything with the ID 0x10ec:0x8168, as there seems to
# be no way to get the MAC version from userspace - and certainly not before the driver is
# loaded. Other PCI IDs may need adding..

PREREQ=""
prereqs()
{
    echo "$PREREQ"
}
case $1 in
# get pre-requisites
prereqs)
    prereqs
    exit 0
    ;;
esac

disable_msi () {
    for i in /sys/bus/pci/devices/*; do 
        if [ $(cat $i/vendor) = "0x10ec" -a $(cat $i/device) = "0x8168" ]; then
            echo 0 >$i/msi_bus
        fi
    done
}

for x in $(cat /proc/cmdline); do
        case ${x} in
        r8169_disable_msi)
        disable_msi
        break
                ;;
        esac
done

Update #1:

OP reset the BIOS, and removed CPU overclocking, and so far, it's run for 6 days without difficulty. It may take a little more time to confirm it's fixed.