Kernel Oops - unable to handle kernel NULL pointer dereference; RIP is at 0010:set_root+0x27/0xc0

[Simon Schneider]

After login into the gnome session, the session freezes, either instantly or after a few seconds ( only mouse is working ). The Oops does not occur on every startup. After a few restarts, the kernel Oops does not occur anymore during the complete session.

Dell Perfomance Checks ( including memory checks ) did not show any failures. BIOS is uptodate ( 1.16.2 for Dell Precision 5530 ).

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: linux-image-5.4.0-37-generic 5.4.0-37.41
ProcVersionSignature: Ubuntu 5.4.0-37.41-generic 5.4.41
Uname: Linux 5.4.0-37-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: scsi 3876 F.... pulseaudio
 /dev/snd/controlC1: scsi 3876 F.... pulseaudio
 /dev/snd/controlC0: scsi 3876 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Wed Jun 24 09:00:05 2020
DistributionChannelDescriptor:
 # This is a distribution channel descriptor
 # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor
 canonical-oem-somerville-xenial-amd64-osp1-20171027-1
EcryptfsInUse: Yes
InstallationDate: Installed on 2019-01-10 (530 days ago)
InstallationMedia: Ubuntu 16.04 "Xenial" - Build amd64 LIVE Binary 20171027-10:57
MachineType: Dell Inc. Precision 5530
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-37-generic root=UUID=2c719e60-4d36-4042-aa72-aa62403b19a1 ro acpi_osi=Linux-Dell-Video alx.enable_wol=1 mem_sleep_default=deep quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-5.4.0-37-generic N/A
 linux-backports-modules-5.4.0-37-generic N/A
 linux-firmware 1.187
SourcePackage: linux
UpgradeStatus: Upgraded to focal on 2020-05-04 (50 days ago)
WifiSyslog:

dmi.bios.date: 04/21/2020
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.16.2
dmi.board.name: 0N0DK2
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 10
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvr1.16.2:bd04/21/2020:svnDellInc.:pnPrecision5530:pvr:rvnDellInc.:rn0N0DK2:rvrA00:cvnDellInc.:ct10:cvr:
dmi.product.family: Precision
dmi.product.name: Precision 5530
dmi.product.sku: 087D
dmi.sys.vendor: Dell Inc.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Simon Schneider (sisc87)]

Cannot reproduce this very issue with the fallback Kernel.

Linux sisc-ws 5.4.0-33-generic #37-Ubuntu SMP Thu May 21 12:53:59 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Instead, seeing some issues with nouveau. See attached dmesg output with older kernel