Kernel panic when building a custom Linux Kernel using buildroot for Zynq-7000

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I’m trying to build a linux kernel, dt (containing custom IP hw configuration) and rootfs following this tutorial:
https://www.youtube.com/watch?v=PxGK7h_DYfE&t=51s
The tutorial does it mainly for a ZU+, but I just have a microzed (Zynq-7000).
So far I was aleady able to set up fsbl and the dts with vivado and vitis. I also build u-boot and so far this part seems to works. Now I want to use buildroot to build a kernel from linux-xlnx. I used xilinx_zynq_defconfig to create the kernel .config file.
The Buildroot config file:

BR2_arm=y
BR2_cortex_a9=y
BR2_ARM_ENABLE_NEON=y
BR2_ARM_ENABLE_VFP=y
BR2_KERNEL_HEADERS_5_4=y
BR2_TOOLCHAIN_BUILDROOT_CXX=y
BR2_TOOLCHAIN_BUILDROOT_GLIBC=y


#Linux Kernel

BR2_LINUX_KERNEL=y
BR2_LINUX_KERNEL_CUSTOM_GIT=y
BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/Xilinx/linux-xlnx.git"
BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="xilinx-v2020.1"
BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="${BR2_EXTERNAL_MYDIR_PATH}/board/kernel.config"
BR2_LINUX_KERNEL_DTS_SUPPORT=y
BR2_LINUX_KERNEL_USE_CUSTOM_DTS=y
BR2_LINUX_KERNEL_CUSTOM_DTS_PATH="${BR2_EXTERNAL_MYDIR_PATH}/board/kernel.dts"

#Packages

BR2_PACKAGE_HOST_DOSFSTOOLS=y
BR2_PACKAGE_HOST_GENIMAGE=y
BR2_PACKAGE_HOST_MTOOLS=y
BR2_PACKAGE_DROPBEAR=y
BR2_PACKAGE_DROPBEAR_DISABLE_REVERSEDNS=y
BR2_PACKAGE_DROPBEAR_WTMP=y
BR2_PACKAGE_DROPBEAR_LASTLOG=y
BR2_PACKAGE_ETHTOOL=y
BR2_PACKAGE_HAVEGED=y
BR2_PACKAGE_LIBGPIOD=y
BR2_PACKAGE_LIBGPIOD_TOOLS=y
BR2_PACKAGE_SPI_TOOLS=y
BR2_PACKAGE_TCF_AGENT=y

#BR2_PACKAGE_CUSTOM=y

#Target

BR2_TARGET_GENERIC_GETTY_BAUDRATE_115200=y
BR2_TARGET_GENERIC_GETTY_PORT="ttyPS0"
BR2_TARGET_GENERIC_HOSTNAME="CUstomZU"
BR2_TARGET_GENERIC_ISSUE="Welcome to Martins uzed"
BR2_TARGET_GENERIC_PASSWD_SHA512=y
BR2_TARGET_GENERIC_ROOT_PASSWD="root"
BR2_TARGET_ROOTFS_CPIO=y
BR2_TARGET_ROOTFS_CPIO_LZMA=y
BR2_TARGET_ROOTFS_CPIO_TAR=n

# RootFS

BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_MYDIR_PATH)/board/rootfs-overlay"
BR2_ROOTFS_POST_IMAGE_SCRIPT="$(BR2_EXTERNAL_MYDIR_PATH)/board/post-image.sh"

an build it, then I create an image with kernel, dtb and rootfs using the following its (FIT) file:

/dts-v1/;
/ {
    description = "Simple image with single Linux kernel";
    images {
        kernel-1 {
            description = "Linux kernel";
            data = /incbin/("./zImage.gz");
            type = "kernel";
            arch = "arm";
            os = "linux";
            compression = "gzip";
            load = <0x8000>;
            entry = <0x8000>;
            hash-1 {
                algo = "sha1";
            };
        };

        fdt-1 {
            description = "Device Tree blob";
            data = /incbin/("./kernel.dtb");
            type = "flat_dt";
            arch = "arm";
            compression = "none";
            hash-1 {
                algo = "sha1";
            };
        };
        ramdisk-1 {
            description = "petalinux-image-minimal";
            data = /incbin/("./rootfs.cpio");
            type = "ramdisk";
            arch = "ARM";
            os = "linux";
            compression = "none";
            hash {
                algo = "sha256";
            };
        };
        
    };

    configurations {
        default = "config-1";

        config-1 {
            description = "Boot Linux kernel";
            kernel = "kernel-1";
            fdt = "fdt-1";
            ramdisk = "ramdisk-1";
            hash-1 {
                algo = "sha1";
            };
        };
    };
}; 

u-boot loads the itb file form SD card and starts the kernel which runs into a kernel panic:

    U-Boot 2020.01 (Dec 29 2021 - 11:49:08 +0100)
    
    CPU:   Zynq 7z010
    Silicon: v3.1
    DRAM:  ECC disabled 1 GiB
    Flash: 0 Bytes
    NAND:  0 MiB
    MMC:   mmc@e0100000: 0
    Loading Environment from SPI Flash... SF: Detected s25fl128s with page size 256 Bytes, erase size 64 KiB, total 16 MiB
    *** Warning - bad CRC, using default environment
    
    In:    serial@e0001000
    Out:   serial@e0001000
    Err:   serial@e0001000
    Net:   
    ZYNQ GEM: e000b000, mdio bus e000b000, phyaddr -1, interface rgmii-id
    
    Warning: ethernet@e000b000 (eth0) using random MAC address - 72:da:85:32:49:f9
    eth0: ethernet@e000b000
    Hit any key to stop autoboot:  0 
    Copying Linux from SDCard to RAM...
    13309917 bytes read in 1130 ms (11.2 MiB/s)
 Loading kernel from FIT Image at 03000000 ...
       Using 'config-1' configuration
       Verifying Hash Integrity ... OK
       Trying 'kernel-1' kernel subimage
         Description:  Linux kernel
         Type:         Kernel Image
         Compression:  gzip compressed
         Data Start:   0x030000c8
         Data Size:    4182451 Bytes = 4 MiB
         Architecture: ARM
         OS:           Linux
         Load Address: 0x00008000
         Entry Point:  0x00008000
         Hash algo:    sha1
         Hash value:   4a503e5aa2d56ace0fe0084206c222f1a5707b83
       Verifying Hash Integrity ... sha1+ OK
 Loading ramdisk from FIT Image at 03000000 ...
       Using 'config-1' configuration
       Verifying Hash Integrity ... OK
       Trying 'ramdisk-1' ramdisk subimage
         Description:  petalinux-image-minimal
         Type:         RAMDisk Image
         Compression:  uncompressed
         Data Start:   0x0340028c
         Data Size:    9113600 Bytes = 8.7 MiB
         Architecture: ARM
         OS:           Linux
         Load Address: unavailable
         Entry Point:  unavailable
         Hash algo:    sha256
         Hash value:   9305eec29a98a21cec5f5b7717b9be8e88cc898242df616289acfdbf10cf3c94
       Verifying Hash Integrity ... sha256+ OK
  Loading fdt from FIT Image at 03000000 ...
       Using 'config-1' configuration
       Verifying Hash Integrity ... OK
       Trying 'fdt-1' fdt subimage
         Description:  Device Tree blob
         Type:         Flat Device Tree
         Compression:  uncompressed
         Data Start:   0x033fd368
         Data Size:    11874 Bytes = 11.6 KiB
         Architecture: ARM
         Hash algo:    sha1
         Hash value:   fbd24a6bd4bcc30bc443ecf7edfdb13ba70c26ab
       Verifying Hash Integrity ... sha1+ OK
       Booting using the fdt blob at 0x33fd368
       Uncompressing Kernel Image
       Loading Ramdisk to 3e259000, end 3eb0a000 ... OK
       Loading Device Tree to 3e253000, end 3e258e61 ... OK
    
    Starting kernel ...
    
    Booting Linux on physical CPU 0x0
    Linux version 5.4.0-xilinx (martin@ubuntu) (gcc version 10.3.0 (Buildroot 2021.11-575-gcf494c78c1)) #16 SMP PREEMPT Wed Dec 29 20:22:29 CET 2021
    CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=18c5387d
    CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
    OF: fdt: Machine model: xlnx,zynq-7000
    earlycon: cdns0 at MMIO 0xe0001000 (options '115200n8')
    printk: bootconsole [cdns0] enabled
    Memory policy: Data cache writealloc
    cma: Reserved 16 MiB at 0x3f000000
    8<--- cut here ---
    Unable to handle kernel paging request at virtual address fe253000
    pgd = (ptrval)
    [fe253000] *pgd=00000000
    Internal error: Oops - BUG: 5 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.0-xilinx #16
    Hardware name: Xilinx Zynq Platform
    PC is at fdt32_ld+0x0/0xc
    LR is at fdt_check_header+0x10/0x144
    pc : [<c0677ca4>]    lr : [<c0677d6c>]    psr: a00000d3
    sp : c0a01f20  ip : 00a5237f  fp : c0a104cc
    r10: c085c5a8  r9 : c091f758  r8 : 00000000
    r7 : fe253000  r6 : c0a4bbcc  r5 : c0a0823c  r4 : c091f758
    r3 : fe253000  r2 : d00dfeed  r1 : 00000000  r0 : fe253000
    Flags: NzCv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment none
    Control: 18c5387d  Table: 0000404a  DAC: 00000051
    Process swapper (pid: 0, stack limit = 0x(ptrval))
    Stack: (0xc0a01f20 to 0xc0a02000)
    1f20: c091f758 c0a0823c c0a4bbcc c0537628 c091f758 c0a0823c c0a06e40 c0a310c0
    1f40: c0a40c90 efffeec0 c085c5a8 c09208a4 00000000 0000000c c092d398 c090418c
    1f60: ffffffff 18c5387d c0a30f40 00000000 00000000 00000001 413fc090 18c5387d
    1f80: 00000000 c0154e88 c07f3e2d 00000000 00000001 c0900330 c0a30f40 c0a03c40
    1fa0: 00000000 00000001 413fc090 18c5387d 00000000 c090095c 00000000 00000000
    1fc0: 00000000 00000000 00000000 c092fa40 00000000 00000000 00000000 c0900330
    1fe0: 00000051 10c0387d 00000000 3e253000 413fc090 00000000 00000000 00000000
    [<c0677ca4>] (fdt32_ld) from [<c0677d6c>] (fdt_check_header+0x10/0x144)
    [<c0677d6c>] (fdt_check_header) from [<c0537628>] (__unflatten_device_tree+0x28/0xfc)
    [<c0537628>] (__unflatten_device_tree) from [<c09208a4>] (unflatten_device_tree+0x24/0x40)
    [<c09208a4>] (unflatten_device_tree) from [<c090418c>] (setup_arch+0x64c/0xa9c)
    [<c090418c>] (setup_arch) from [<c090095c>] (start_kernel+0x58/0x41c)
    [<c090095c>] (start_kernel) from [<00000000>] (0x0)
    Code: ebf217db e28dd014 e49df004 c0677b9c (e5900000) 
    random: get_random_bytes called from init_oops_id+0x24/0x48 with crng_init=0
    ---[ end trace 0000000000000000 ]---
    Kernel panic - not syncing: Attempted to kill the idle task!
    ---[ end Kernel panic - not syncing:  Attempted to kill the idle task! ]---

Possibly my kernel config is wrong or the rootFS is misconfigured, but not sure where to start since the kernel log is not really helping me.