Unable to boot kernel since 4.18 on Armada XP MV78230

[raumzeit]

Hi,
I've been running ArchLinuxARM on my Lenovo IX4-300D for quite a while using the linux-armv7 kernel without major problems. However, since version 4.18, it seems that loading the kernel fails for some reason. My serial console output simply stops like this:
$this->bbcode_second_pass_code('', '
BootROM 1.15
Booting from NAND flash
DDR3 Training Sequence - Ver 2.3.4
DDR3 Training Sequence - Ended Successfully
BootROM: Image checksum verification PASSED

__ __ _ _
| \/ | __ _ _ ____ _____| | |
| |\/| |/ _` | '__\ \ / / _ \ | |
| | | | (_| | | \ V / __/ | |
|_| |_|\__,_|_| \_/ \___|_|_|
_ _ ____ _
| | | | | __ ) ___ ___ | |_
| | | |___| _ \ / _ \ / _ \| __|
| |_| |___| |_) | (_) | (_) | |_
\___/ |____/ \___/ \___/ \__|
** LOADER 2.3.2.6 **


U-Boot 2009.08 (Mar 04 2013 - 11:13:04) Marvell version: 2.3.2 PQ
U-Boot Addressing:
Code: 00600000:006BFFF0
BSS: 00708EC0
Stack: 0x5fff70
PageTable: 0x8e0000
Heap address: 0x900000:0xe00000
Board: DB-78230-BP rev 2.0 Wistron
SoC: MV78230 A0
running 2 CPUs
Custom configuration
CPU: Marvell PJ4B (584) v7 (Rev 2) LE
CPU # 0
CPU @ 1333Mhz, L2 @ 667Mhz
DDR @ 667Mhz, TClock @ 250Mhz
DDR 32Bit Width, FastPath Memory Access
DDR ECC Disabled
PEX 0.0(0): Root Complex Interface, Detected Link X4, GEN 1.1
PEX 1.0(1): Root Complex Interface, Detected Link X1, GEN 2.0
DRAM: 512 MB
CS 0: base 0x00000000 size 512 MB
Addresses 14M - 0M are saved for the U-Boot usage.
NAND: 1024 MiB
Bad block table found at page 524224, version 0x01
Bad block table found at page 524160, version 0x01
nand_read_bbt: Bad block at 0x000013480000
nand_read_bbt: Bad block at 0x00002d5e0000
FPU initialized to Run Fast Mode.
USB 0: Host Mode
USB 1: Host Mode
USB 2: Device Mode
Modules Detected:
MMC: MRVL_MMC: 0
Net: egiga0 [PRIME], egiga1
Hit any key to stop autoboot: 0
(Re)start USB...
USB: Active port: 0
Register 10011 NbrPorts 1
USB EHCI 1.00
scanning bus for devices... 2 USB Device(s) found
Waiting for storage device(s) to settle before scanning...
scanning bus for storage devices... 1 Storage Device(s) found
reading uImage
....................................................................................................................................................................................................................................
.....................................................................................................................................................................

6339154 bytes read
## Booting kernel from Legacy Image at 02000000 ...
Image Name: linux-armv7-ix4-300d
Created: 2018-11-02 7:26:39 UTC
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 6339090 Bytes = 6 MB
Load Address: 00008000
Entry Point: 00008000
Verifying Checksum ... OK
Loading Kernel Image ...
')

I've already inspected diffs between a running 4.17.12 config and the one introduced with 4.18 to determine what might have changed for Marvell platforms. Also, looking at the device tree files did not result in anything looking suspicious.

Does anyone have a clue what might have changed between 4.17 and 4.18 that could possibly preventing my NAS from loading the kernel image?