Several crashes in /var/crash, here's the last one:-
ProblemType: KernelOops
Annotation: Your system might become unstable now and might need to be restarted.
Date: Fri Jul 23 18:10:54 2021
Failure: oops
OopsText:
BUG: Bad rss-counter state mm:00000000c098a229 idx:2 val:-1
usblp0: removed
usblp 1-5:1.0: usblp0: USB Bidirectional printer dev 3 if 0 alt 0 proto 2 vid 0x04F9 pid 0x02EC
<44>[ 18.329026] systemd-journald[358]: File /var/log/journal/b022dca21fd4480baeeb84f47ab439d3/user-1000.journal corrupted or uncleanly shut down, renaming and replacing.
vboxdrv: loading out-of-tree module taints kernel.
vboxdrv: module verification failed: signature and/or required key missing - tainting kernel
vboxdrv: Found 8 processor cores
vboxdrv: TSC mode is Invariant, tentative frequency 2303999142 Hz
vboxdrv: Successfully loaded version 6.1.24 r145767 (interface 0x00300000)
VBoxNetFlt: Successfully started.
VBoxNetAdp: Successfully started.
Bluetooth: RFCOMM TTY layer initialized
Bluetooth: RFCOMM socket layer initialized
Bluetooth: RFCOMM ver 1.11
rfkill: input handler disabled
[UFW BLOCK] IN=enp3s0f1 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
[UFW BLOCK] IN=wlp2s0 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
[UFW BLOCK] IN=enp3s0f1 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
[UFW BLOCK] IN=wlp2s0 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
[UFW BLOCK] IN=enp3s0f1 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
[UFW BLOCK] IN=wlp2s0 OUT= MAC=01:00:5e:00:00:01:80:20:da:95:bc:56:08:00 SRC=192.168.1.254 DST=224.0.0.1 LEN=36 TOS=0x00 PREC=0x00 TTL=1 ID=0 DF PROTO=2
Package: linux-image-4.15.0-151-generic 4.15.0-151.157
SourcePackage: linux
Tags: kernel-oops
Uname: Linux 4.15.0-151-generic x86_64
The system is a laptop from Entroware based on Clevo and has 8 logical CPUs:-
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 8
On-line CPU(s) list: 0-7
Thread(s) per core: 2
Core(s) per socket: 4
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 158
Model name: Intel(R) Core(TM) i5-8300H CPU @ 2.30GHz
Stepping: 10
CPU MHz: 2000.295
CPU max MHz: 4000.0000
CPU min MHz: 800.0000
BogoMIPS: 4599.93
Virtualisation: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 8192K
NUMA node0 CPU(s): 0-7
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp md_clear flush_l1d
USB Config:-
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 5986:2110 Acer, Inc
Bus 001 Device 003: ID 04f9:02ec Brother Industries, Ltd MFC-J870DW
Bus 001 Device 005: ID 8087:07dc Intel Corp. Bluetooth wireless interface
Bus 001 Device 002: ID 0d8c:0104 C-Media Electronics, Inc. CM103+ Audio Controller
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
PCI Config:-
00:00.0 Host bridge: Intel Corporation Device 3e10 (rev 07)
00:02.0 VGA compatible controller: Intel Corporation Device 3e9b
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 Lake PCH Thermal Controller (rev 10)
00:14.0 USB controller: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller (rev 10)
00:14.2 RAM memory: Intel Corporation Cannon Lake PCH Shared SRAM (rev 10)
00:16.0 Communication controller: Intel Corporation Cannon Lake PCH HECI Controller (rev 10)
00:17.0 SATA controller: Intel Corporation Device a353 (rev 10)
00:1d.0 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port 9 (rev f0)
00:1d.5 PCI bridge: Intel Corporation Device a335 (rev f0)
00:1d.6 PCI bridge: Intel Corporation Device a336 (rev f0)
00:1f.0 ISA bridge: Intel Corporation Device a30d (rev 10)
00:1f.3 Audio device: Intel Corporation Cannon Lake PCH cAVS (rev 10)
00:1f.4 SMBus: Intel Corporation Cannon Lake PCH SMBus Controller (rev 10)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH SPI Controller (rev 10)
01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981
02:00.0 Network controller: Intel Corporation Wireless 3160 (rev 93)
03:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTL8411B PCI Express Card Reader (rev 01)
03:00.1 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 12)
This has only started happening since using 4.15.0-151. Reverting to 4.15.0-147 makes the system stable.