Please refer to https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.57
for the changelog of this version. Since it introduces
architecture-dependent rootfile changes due to CPU side-channel
mitigations, changes to ARM rootfiles have been omitted due to the lack
of hardware.
Supposed hardening changes will be submitted separately.
Signed-off-by: Peter Müller <peter.mueller@ipfire.org>