To reproduce this you need to install "kernel-rt-debug" and
run libguestfs-test-tool.

Removing TestOnly because:

***   This is unapproved because at least one of the BZs contains the TestOnly keyword. TestOnly keyword must be removed in order to pass approval.

Test with supermin-5.2.1-8.el9.x86_64:

Steps:

1. On rhel9.1 host
# rpm -q kernel kernel-rt kernel-rt-debug
kernel-5.14.0-72.el9.x86_64
kernel-rt-5.14.0-72.rt21.72.el9.x86_64
kernel-rt-debug-5.14.0-72.rt21.72.el9.x86_64

2.
# libguestfs-test-tool
PATH=/root/.local/bin:/root/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
XDG_RUNTIME_DIR=/run/user/0
SELinux: Enforcing
guestfs_get_append: (null)
guestfs_get_autosync: 1
guestfs_get_backend: libvirt
guestfs_get_backend_settings: []
guestfs_get_cachedir: /var/tmp
guestfs_get_hv: /usr/libexec/qemu-kvm
guestfs_get_memsize: 1280
guestfs_get_network: 0
guestfs_get_path: /usr/lib64/guestfs
guestfs_get_pgroup: 0
guestfs_get_program: libguestfs-test-tool
guestfs_get_recovery_proc: 1
guestfs_get_smp: 1
guestfs_get_sockdir: /tmp
guestfs_get_tmpdir: /tmp
guestfs_get_trace: 0
guestfs_get_verbose: 1
host_cpu: x86_64
Launching appliance, timeout set to 600 seconds.
libguestfs: launch: program=libguestfs-test-tool
libguestfs: launch: version=1.48.0rhel=9,release=2.el9,libvirt
libguestfs: launch: backend registered: direct
libguestfs: launch: backend registered: libvirt
libguestfs: launch: backend=libvirt
libguestfs: launch: tmpdir=/tmp/libguestfsIGP13Z
libguestfs: launch: umask=0022
libguestfs: launch: euid=0
libguestfs: libvirt version = 8001000 (8.1.0)
libguestfs: guest random name = guestfs-aj0mi535onc5e1hi
libguestfs: connect to libvirt
libguestfs: opening libvirt handle: URI = qemu:///system, auth = default+wrapper, flags = 0
libguestfs: successfully opened libvirt handle: conn = 0x5631616bf030
libguestfs: qemu version (reported by libvirt) = 6002000 (6.2.0)
libguestfs: get libvirt capabilities
libguestfs: parsing capabilities XML
libguestfs: parsing domcapabilities XML
libguestfs: build appliance
libguestfs: begin building supermin appliance
libguestfs: run supermin
libguestfs: command: run: /usr/bin/supermin
libguestfs: command: run: \ --build
libguestfs: command: run: \ --verbose
libguestfs: command: run: \ --if-newer
libguestfs: command: run: \ --lock /var/tmp/.guestfs-0/lock
libguestfs: command: run: \ --copy-kernel
libguestfs: command: run: \ -f ext2
libguestfs: command: run: \ --host-cpu x86_64
libguestfs: command: run: \ /usr/lib64/guestfs/supermin.d
libguestfs: command: run: \ -o /var/tmp/.guestfs-0/appliance.d
supermin: version: 5.2.1
supermin: rpm: detected RPM version 4.16
supermin: rpm: detected RPM architecture x86_64
supermin: package handler: fedora/rpm
supermin: acquiring lock on /var/tmp/.guestfs-0/lock
supermin: build: /usr/lib64/guestfs/supermin.d
supermin: reading the supermin appliance
supermin: build: visiting /usr/lib64/guestfs/supermin.d/base.tar.gz type gzip base image (tar)
supermin: build: visiting /usr/lib64/guestfs/supermin.d/daemon.tar.gz type gzip base image (tar)
supermin: build: visiting /usr/lib64/guestfs/supermin.d/excludefiles type uncompressed excludefiles
supermin: build: visiting /usr/lib64/guestfs/supermin.d/hostfiles type uncompressed hostfiles
supermin: build: visiting /usr/lib64/guestfs/supermin.d/init.tar.gz type gzip base image (tar)
supermin: build: visiting /usr/lib64/guestfs/supermin.d/packages type uncompressed packages
supermin: build: visiting /usr/lib64/guestfs/supermin.d/udev-rules.tar.gz type gzip base image (tar)
supermin: build: visiting /usr/lib64/guestfs/supermin.d/zz-packages-rescue type uncompressed packages
supermin: build: visiting /usr/lib64/guestfs/supermin.d/zz-packages-rsync type uncompressed packages
supermin: build: visiting /usr/lib64/guestfs/supermin.d/zz-packages-xfs type uncompressed packages
supermin: build: visiting /usr/lib64/guestfs/supermin.d/zz-winsupport.tar.gz type gzip base image (tar)
supermin: mapping package names to installed packages
supermin: resolving full list of package dependencies
supermin: build: 193 packages, including dependencies
supermin: build: 35241 files
supermin: build: 8250 files, after matching excludefiles
supermin: build: 8264 files, after adding hostfiles
supermin: build: 8252 files, after removing unreadable files
supermin: build: 8279 files, after munging
supermin: kernel: looking for kernel using environment variables ...
supermin: kernel: looking for kernels in /lib/modules/*/vmlinuz ...
supermin: kernel: picked vmlinuz /lib/modules/5.14.0-72.rt21.72.el9.x86_64/vmlinuz
supermin: kernel: kernel_version 5.14.0-72.rt21.72.el9.x86_64
supermin: kernel: modpath /lib/modules/5.14.0-72.rt21.72.el9.x86_64
...
===== TEST FINISHED OK =====

Supermin ignored the debug RT kernel and use RT kernel instead. The behavior is as expected.

Verified this bug since the test case for this bug has been automated and passed in the latest nightly compose test.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (supermin bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2022:7965