Ubuntu – Ubuntu 20.04 freezing and crashing

I recently upgraded from version 18 LTS to 20 using Software update, and am noticing random freezing or crashing of the system ever since.

Symptoms
The crash usually starts with some windows freezing completely (no responses) (vs code or firefox), and in a short period (30s-60s) the whole system freezes and the only way to proceed is a reboot via power button.
Lately, i also noticed some instant crashes, with the whole screen going black.
I also noticed crashing usually occurs when using firefox or vs code (but not when intentionally executing hard calculations).

/var/crash

The lastest file is 3 days old, the last crash was today.

urh@urh-laptop:/var/crash$ ls
linux-image-5.4.0-54-generic.203356.crash    _opt_teamviewer_tv_bin_teamviewerd.0.uploaded  _usr_share_code_code.1000.crash
linux-image-5.4.0-54-generic.213157.crash    _usr_bin_gnome-shell.1000.crash                _usr_share_code_code.1000.upload
_opt_teamviewer_tv_bin_teamviewerd.0.crash   _usr_bin_gnome-shell.1000.upload               _usr_share_code_code.1000.uploaded
_opt_teamviewer_tv_bin_teamviewerd.0.upload  _usr_bin_gnome-shell.1000.uploaded

Parts from _usr_share_code.1000.crash:

  GNU nano 4.8                                                                          _usr_share_code_code.1000.crash                                                                                    
ProblemType: Crash
Architecture: amd64
Date: Tue Dec  1 14:01:31 2020
DistroRelease: Ubuntu 20.04
ExecutablePath: /usr/share/code/code
ExecutableTimestamp: 1603764692
ProcCmdline: /usr/share/code/code\ --type=renderer\ --disable-color-correct-rendering\ --no-sandbox\ --field-trial-handle=11739126107242220802,6576820938724679016,131072\ --enable-features=WebComponents>
ProcCwd: /home/urh
ProcEnviron:
ProcMaps:
.
.
.
ProcStatus:
 Name:  code
 Umask: 0002
 State: S (sleeping)
 Tgid:  288605
 Ngid:  0
 Pid:   288605
 PPid:  288509
 TracerPid:     0
 Uid:   1000    1000    1000    1000
 Gid:   1000    1000    1000    1000
 FDSize:        128
 Groups:        4 24 27 30 46 116 126 127 1000
 NStgid:        288605
 NSpid: 288605
 NSpgid:        153351
 NSsid: 153351
 VmPeak:         8625096 kB
 VmSize:         4626800 kB
 VmLck:        0 kB
 VmPin:        0 kB
 VmHWM:   194540 kB
 VmRSS:   125928 kB
 RssAnon:          38616 kB
 RssFile:          87292 kB
 RssShmem:            20 kB
 VmData:          267896 kB
 VmStk:      132 kB
 VmExe:   112352 kB
 VmLib:        0 kB
 VmPTE:      844 kB
 VmSwap:               0 kB
 HugetlbPages:         0 kB
 CoreDumping:   1
 THP_enabled:   1
 Threads:       20
 SigQ:  0/47179
SigPnd:        0000000000000000
 ShdPnd:        0000000000000000
 SigBlk:        0000000000000000
 SigIgn:        0000000000000002
 SigCgt:        00000001800010f8
 CapInh:        0000000000000000
 CapPrm:        0000000000000000
 CapEff:        0000000000000000
 CapBnd:        0000003fffffffff
 CapAmb:        0000000000000000
 NoNewPrivs:    0
 Seccomp:       0
 Speculation_Store_Bypass:      thread vulnerable
 Cpus_allowed:  f
 Cpus_allowed_list:     0-3
 Mems_allowed:  00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,000000>
 Mems_allowed_list:     0
 voluntary_ctxt_switches:       11320
 nonvoluntary_ctxt_switches:    4009
Signal: 11
Uname: Linux 5.4.0-54-generic x86_64
UserGroups: adm cdrom dip kvm lpadmin plugdev sambashare sudo

INFO

I am running (dualboot) Ubuntu 20.04.1 LTS on Acer Spin 3 with 12gb ram, Intel® Core™ i7-7500U CPU @ 2.70GHz × 4, and Mesa Intel® HD Graphics 620 (KBL GT2).

Gnome version: 3.36.3

Running journalctl -b -1 -e reveals:

dec 05 14:16:12 urh-laptop mtp-probe[466455]: bus: 1, device: 11 was not an MTP device
dec 05 14:16:14 urh-laptop systemd[1]: run-snapd-ns-snap\x2dstore.mnt.mount: Succeeded.
dec 05 14:16:14 urh-laptop systemd[1]: Unmounted /run/snapd/ns/snap-store.mnt.
dec 05 14:16:14 urh-laptop systemd[1]: Unmounting /run/snapd/ns...
dec 05 14:16:14 urh-laptop systemd[1]: run-snapd-ns.mount: Succeeded.
dec 05 14:16:14 urh-laptop systemd[1]: Unmounted /run/snapd/ns.
dec 05 14:16:14 urh-laptop systemd[1]: Stopped target Local File Systems (Pre).
dec 05 14:16:14 urh-laptop systemd[1]: Stopped target Swap.
dec 05 14:16:14 urh-laptop systemd[1]: Deactivating swap /dev/disk/by-id/ata-ST1000LM035-1RK172_WES1A7S2-part3...
dec 05 14:16:14 urh-laptop systemd[1]: systemd-tmpfiles-setup-dev.service: Succeeded.
dec 05 14:16:14 urh-laptop systemd[1]: Stopped Create Static Device Nodes in /dev.
dec 05 14:16:14 urh-laptop systemd[1]: systemd-sysusers.service: Succeeded.
dec 05 14:16:14 urh-laptop systemd[1]: Stopped Create System Users.
dec 05 14:16:14 urh-laptop systemd[1]: systemd-remount-fs.service: Succeeded.
dec 05 14:16:14 urh-laptop systemd[1]: Stopped Remount Root and Kernel File Systems.
dec 05 14:16:14 urh-laptop systemd[1]: Reached target Shutdown.
dec 05 14:16:15 urh-laptop systemd[1]: dev-disk-by\x2dpath-pci\x2d0000:00:17.0\x2data\x2d1\x2dpart3.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/disk/by-path/pci-0000:00:17.0-ata-1-part3.
dec 05 14:16:15 urh-laptop systemd[1]: dev-disk-by\x2did-ata\x2dST1000LM035\x2d1RK172_WES1A7S2\x2dpart3.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/disk/by-id/ata-ST1000LM035-1RK172_WES1A7S2-part3.
dec 05 14:16:15 urh-laptop systemd[1]: dev-disk-by\x2did-wwn\x2d0x5000c5009d10879a\x2dpart3.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/disk/by-id/wwn-0x5000c5009d10879a-part3.
dec 05 14:16:15 urh-laptop systemd[1]: dev-disk-by\x2dpartuuid-00af4d5c\x2d43e1\x2d4918\x2d8b9e\x2d8f331d86bab4.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/disk/by-partuuid/00af4d5c-43e1-4918-8b9e-8f331d86bab4.
dec 05 14:16:15 urh-laptop systemd[1]: dev-sda3.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/sda3.
dec 05 14:16:15 urh-laptop systemd[1]: dev-disk-by\x2duuid-86c68832\x2d3661\x2d488d\x2db520\x2dbb94356b7b1f.swap: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Deactivated swap /dev/disk/by-uuid/86c68832-3661-488d-b520-bb94356b7b1f.
dec 05 14:16:15 urh-laptop systemd[1]: Reached target Unmount All Filesystems.
dec 05 14:16:15 urh-laptop systemd[1]: Reached target Final Step.
dec 05 14:16:15 urh-laptop systemd[1]: systemd-poweroff.service: Succeeded.
dec 05 14:16:15 urh-laptop systemd[1]: Finished Power-Off.
dec 05 14:16:15 urh-laptop systemd[1]: Reached target Power-Off.
dec 05 14:16:15 urh-laptop systemd[1]: Shutting down.
dec 05 14:16:15 urh-laptop systemd-shutdown[1]: Syncing filesystems and block devices.
dec 05 14:16:16 urh-laptop systemd-shutdown[1]: Sending SIGTERM to remaining processes...
dec 05 14:16:16 urh-laptop systemd-journald[272]: Journal stopped

urh@urh-laptop:/var/crash$ free -h
              total        used        free      shared  buff/cache   available
Mem:           11Gi       1,6Gi       7,2Gi       330Mi       2,8Gi       9,3Gi
Swap:         9,3Gi          0B       9,3Gi

urh@urh-laptop:/var/crash$ sysctl vm.swappiness
vm.swappiness = 60

urh@urh-laptop:/var/crash$ sudo dmidecode -s bios-version
[sudo] password for urh: 
V1.04

urh@urh-laptop:/$ grep -i swap /etc/fstab
# swap was on /dev/sdb3 during installation
UUID=86c68832-3661-488d-b520-bb94356b7b1f none            swap    sw              0       0

urh@urh-laptop:/$ ls -al /usr/share/gnome-shell/extensions
total 20
drwxr-xr-x 5 root root 4096 nov  3 00:39 .
drwxr-xr-x 7 root root 4096 nov  3 01:33 ..
drwxr-xr-x 2 root root 4096 nov  3 00:39 desktop-icons@csoriano
drwxr-xr-x 3 root root 4096 nov  2 22:03 ubuntu-appindicators@ubuntu.com
drwxr-xr-x 3 root root 4096 dec  1 18:17 ubuntu-dock@ubuntu.com

Ubutnu 18 never crashed. I am a noob, so i cant make anything usefull from crash reporst. I can also provide stuff from /var/log/

Update #1

swapon

urh@urh-laptop:~$ swapon --show
NAME      TYPE      SIZE USED PRIO
/dev/sda3 partition 9,3G   0B   -2

urh@urh-laptop:~$ sudo blkid
[sudo] password for urh: 
/dev/sda3: UUID="86c68832-3661-488d-b520-bb94356b7b1f" TYPE="swap" PARTUUID="00af4d5c-43e1-4918-8b9e-8f331d86bab4"
/dev/sda2: UUID="ac6f5269-f799-4b38-a91a-3688bd842038" TYPE="ext4" PARTUUID="8e1ba2b7-fc9d-4fbc-bbb3-a00170fd283c"
/dev/loop0: TYPE="squashfs"
/dev/loop1: TYPE="squashfs"
/dev/loop2: TYPE="squashfs"
/dev/loop3: TYPE="squashfs"
/dev/loop4: TYPE="squashfs"
/dev/loop5: TYPE="squashfs"
/dev/loop6: TYPE="squashfs"
/dev/loop7: TYPE="squashfs"
/dev/sda1: LABEL="Podatki" UUID="16161663161643E1" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="ce22c83a-64d0-4091-9773-b65d637375e6"
/dev/sda4: UUID="77ea92d2-e175-4648-a977-726e2ebae872" TYPE="ext4" PARTUUID="da5c0b1c-0285-4717-a98d-e280babb0044"
/dev/sdb1: LABEL="System Reserved" UUID="A620DA0620D9DCFD" TYPE="ntfs" PARTUUID="9abd075d-01"
/dev/sdb2: UUID="F4D8E4B1D8E47372" TYPE="ntfs" PARTUUID="9abd075d-02"
/dev/sdb3: UUID="26AED78EAED754C1" TYPE="ntfs" PARTUUID="9abd075d-03"
/dev/loop8: TYPE="squashfs"
/dev/loop9: TYPE="squashfs"

urh@urh-laptop:~$ cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sdb2 during installation
UUID=ac6f5269-f799-4b38-a91a-3688bd842038 /               ext4    errors=remount-ro 0       1
# /home was on /dev/sdb4 during installation
UUID=77ea92d2-e175-4648-a977-726e2ebae872 /home           ext4    defaults        0       2
# swap was on /dev/sdb3 during installation
UUID=86c68832-3661-488d-b520-bb94356b7b1f none            swap    sw              0       0
/dev/disk/by-uuid/16161663161643E1 /mnt/Podatki auto nosuid,nodev,nofail,x-gvfs-show,x-gvfs-name=Podatki 0 0
/dev/disk/by-uuid/F4D8E4B1D8E47372 /mnt/dataFromWindows auto nosuid,nodev,nofail,x-gvfs-show,x-gvfs-name=Data%20From%20Windows 0 0

drwxrwsrwt  2 root     whoopsie     4096 dec  5 15:18 .
drwxr-xr-x 14 root     root         4096 apr 25  2020 ..
-rw-r--r--  1 kernoops whoopsie     2787 dec  1 15:57 linux-image-5.4.0-54-generic.203356.crash
-rw-r--r--  1 kernoops whoopsie     2922 nov 29 19:45 linux-image-5.4.0-54-generic.213157.crash
-rw-r-----  1 root     whoopsie  1072334 dec  5 15:05 _opt_teamviewer_tv_bin_teamviewerd.0.crash
-rw-r--r--  1 root     whoopsie        0 dec  2 17:13 _opt_teamviewer_tv_bin_teamviewerd.0.upload
-rw-------  1 whoopsie whoopsie       37 dec  2 17:13 _opt_teamviewer_tv_bin_teamviewerd.0.uploaded
-rw-r-----  1 urh      whoopsie 63037944 nov 30 19:57 _usr_bin_gnome-shell.1000.crash
-rw-r--r--  1 urh      whoopsie        0 nov 30 19:57 _usr_bin_gnome-shell.1000.upload
-rw-------  1 whoopsie whoopsie       37 nov 30 19:57 _usr_bin_gnome-shell.1000.uploaded
-rw-r-----  1 urh      whoopsie 74784629 dec  1 14:01 _usr_share_code_code.1000.crash
-rw-r-----  1 urh      whoopsie 74784631 dec  5 15:18 _usr_share_code_code.1000.crash.save
-rw-r--r--  1 urh      whoopsie        0 dec  1 14:01 _usr_share_code_code.1000.upload
-rw-------  1 whoopsie whoopsie       37 dec  1 14:01 _usr_share_code_code.1000.uploaded

Model: Acer Spin 3

Model Number: N16P9

Update #2

Serial number: NXGK9AA0216480116F7200

SNID: 64800446372

Update #3

urh@urh-laptop:~$ ls -al ~/.local/share/gnome-shell/extensions
ls: cannot access '/home/urh/.local/share/gnome-shell/extensions': No such file or directory

urh@urh-laptop:~$ ls -al /usr/share/gnome-shell/extensions
total 20
drwxr-xr-x 5 root root 4096 nov  3 00:39 .
drwxr-xr-x 7 root root 4096 nov  3 01:33 ..
drwxr-xr-x 2 root root 4096 nov  3 00:39 desktop-icons@csoriano
drwxr-xr-x 3 root root 4096 nov  2 22:03 ubuntu-appindicators@ubuntu.com
drwxr-xr-x 3 root root 4096 dec  1 18:17 ubuntu-dock@ubuntu.com

Update #4 – SOLUTION?
As suggested by @heynnema , I updated the BIOS. (anoyingly Acer only produces updates for windows, so that was fun). I also added intel_idle.max_cstate=1 in /etc/default/grub and the crashing have stopped for now.

The hint for changing grub was in error code bug soft lockup CPU#2 stuck for 23 s, which only showed one time when crashing. (Usually the screen just went black without showing the log).