bcache UBSAN log spam

[Matthew Mirvish]

The new 6.5 kernel in mantic causes a large amount of UBSAN warnings at boot when using bcache (see attached dmesg log, truncated after last error). The volume still mounts fine and I haven't observed any data corruption.

There seems to have been some discussion about this on the LKML (although it was in reference to bcachefs but this seems to be coming out of the shared common code between that and bcache): https://<email address hidden>/T/

ProblemType: Bug
DistroRelease: Ubuntu 23.10
Package: linux-image-6.5.0-9-lowlatency 6.5.0-9.9.1
ProcVersionSignature: Ubuntu 6.5.0-9.9.1-lowlatency 6.5.3
Uname: Linux 6.5.0-9-lowlatency x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.27.0-0ubuntu5
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Fri Oct 13 17:40:55 2023
InstallationDate: Installed on 2018-08-03 (1897 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
SourcePackage: linux-signed-lowlatency
UpgradeStatus: Upgraded to mantic on 2023-10-13 (1 days ago)