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2.2.15 Kernel panic when booting the Red Hat Compatible Kernel on a btrfs root partition

If the root partition is formatted using btrfs, the system is unable to boot into the Red Hat Compatible Kernel. This is because the features included in the version of btrfs provided, are not supported on older kernel versions. btrfs is included only as a technology preview for the Red Hat Compatible Kernel and is not fully supported on this kernel.

btrfs is fully supported in production with the Unbreakable Enterprise Kernel. Systems booting into this kernel are unaffected by the issue.

Users must be aware when formatting file systems from the installation ISO, that formatting the root partition with btrfs makes it impossible to boot into the Red Hat Compatible Kernel. Note that btrfs is the default file system for system disks when using the boot-uek.iso. If you are installing from this ISO and you intend to use the RHCK, you must change the default system disk layout in the installer.

(Bug ID 23198167)