zyxel nas540 bootloop after unsuccesfull debian kernel upgrade

I had bad flash of newer kernel on Debian.

I had log like following:

booting kernel of type uimage from /dev/nand0.kernel2.bb
   Verifying Checksum ... Bad Data CRC
 Failed.
booting kernel of type uimage from /dev/nand0.kernel1.bb
ERROR: out of memory

I have managed to upload new kernel.

Now I dont know why I am able to boot from second kernel. From kernel 1 I have this issue:

booting kernel of type uimage from /dev/nand0.kernel1.bb

   Verifying Checksum ... Bad Data CRC
 Failed.

From kernel 2:

 [   20.364539] VFS: Cannot open root device "ubi0:rootfs" or unknown-block(0,0)
[   20.371618] Please append a correct "root=" boot option; here are the available partitions:
[   20.380009] 1f00             256 mtdblock0  (driver?)
[   20.385089] 1f01             512 mtdblock1  (driver?)
[   20.390173] 1f02             256 mtdblock2  (driver?)
[   20.395252] 1f03           10240 mtdblock3  (driver?)
[   20.400336] 1f04           10240 mtdblock4  (driver?)
[   20.405415] 1f05          112640 mtdblock5  (driver?)
[   20.410498] 1f06           10240 mtdblock6  (driver?)
[   20.415576] 1f07          112640 mtdblock7  (driver?)
[   20.420660] 1f08            6144 mtdblock8  (driver?)
[   20.425738] 0800      2930266584 sda  driver: sd
[   20.430389]   0801      2930265088 sda1 81ae083b-429a-4768-9f2c-a38c8ddeb287
[   20.437478] 0810      2930266584 sdb  driver: sd
[   20.442122]   0811      2930265088 sdb1 eceb1340-7ebb-477c-8594-46d3d3ca0f4c
[   20.449210] 0830      1953514584 sdd  driver: sd
[   20.453853]   0831          514048 sdd1 00000000-0000-0000-0000-000000000000
[   20.460940]   0832      1952997952 sdd2 00000000-0000-0000-0000-000000000000
[   20.468025] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

when kernel two is booting default commandline is like following:

commandline: console=ttyS0,115200n8, init=/etc/preinit pcie_gen1_only=yes  mac_addr=,, ip=dhcp root=ubi0:rootfs ubi.mtd=2,2048 rootfstype=ubifs rw noinitrd mtdparts=spi0.0:256k(uloader)ro,512k(barebox)ro,256k(env);comcertonand:10M(config),10M(kernel1),110M(rootfs1),10M(kernel2),110M(rootfs2),-(reserved) usb3_internal_clk=yes
arch_number: 1094

my printenv:

Barebox-C2K >/ printenv
locals:
PATH=/env/bin
ip=dhcp
kernel_loc=nand
rootfs_loc=nand
uloaderimage=microloader-c2kevm.bin
bareboximage=barebox-c2kevm.bin
mfg_kernel_img=uImage_MFG
mfg_rootfs_img=rootfs_ubi.img_MFG
rootfs_type=ubifs
rootfsimage=root.ubifs-128k
kernelimage_type=uimage
kernelimage=uImage
spi_parts=256k(uloader)ro,512k(barebox)ro,256k(env)
spi_device=spi0.0
nand_device=comcertonand
nand_parts=10M(config),10M(kernel1),110M(rootfs1),10M(kernel2),110M(rootfs2),-(reserved)
rootfs_mtdblock_nand=1
autoboot_timeout=3
usb3_internal_clk=yes
bootargs=console=ttyS0,115200n8, init=/etc/preinit pcie_gen1_only=yes  mac_addr=,,
next_bootfrom=1
curr_bootfrom=1
kernel_mtd_1=4
sysimg_mtd_1=5
kernel_mtd_2=6
sysimg_mtd_2=7
MODEL_ID=B103
globals:

I am not able to saveenv.

after every boot

Can somebody help me?

I think I need proper bootsargs

When I boot from command line:

bootm /dev/nand0.kernel2.bb

I can boot with argument I provide in bootargs

Adam