Hi3516D : Kernel Panic while booting from NFS with uboot - embedded-linux

Question

I'm trying to boot my kernel from NFS... i have some problem with env. variables on Uboot.
Actually this is work well with ubuntu v14.04.5 LTS NFS kernel server but v18.04.1 is not.
this is my printenv list :
bootdelay=1
baudrate=115200
bootfile="uImage"
mdio_intf=mii
ram_cmd=setenv bootcmd nand read \$(kernel_addr) 0x200000 0x400000\; nand read \$(rootfs_addr) 0x600000 0x700000\; bootm \$(kernel_addr) \$(rootfs_addr)
ram_args=setenv bootargs root=/dev/ram rw rootfstype=ext4 $(fixed_args) $(mtdparts)
nfs_cmd=setenv bootcmd tftp \$(kernel_addr) \$(kernel_tftp_path)\; bootm \$(kernel_addr)
nfs_args=setenv bootargs root=/dev/nfs noinitrd $(fixed_args) $(mtdparts) ip=$(ipaddr):$(serverip):$(gatewayip):$(netmask):$(hostname)::off nfsroot=$(serverip):$(nfsroot) ethaddr=$(ethaddr)
fixed_args=mem=256M console=ttyAMA0,115200
mtdparts=mtdparts=hinand:1M(boot),1M(env),4M(kernel),7M(rootfs),16M(work),24M(www),6M(fw),3M(log),2M(config),64M(data)
kernel_addr=0x82000000
rootfs_addr=0x82400000
hostname=hi3516d_hi
filesize=515E61
fileaddr=82000000
ethaddr=4A:A4:14:6E:F8:F7
boot_mode=nfs
gatewayip=10.20.0.20
serverip=10.20.9.77
ipaddr=10.20.9.110
netmask=255.255.0.0
nfsroot=/home/thkim/build_h3516d_ptz_rel/target
kernel_tftp_path=thkim_H3516D/kernel/curr.kernel
stdin=serial
stdout=serial
stderr=serial
verify=n
factory=0
bootcmd=tftp $(kernel_addr) $(kernel_tftp_path); bootm $(kernel_addr)
bootargs=root=/dev/nfs noinitrd mem=256M console=ttyAMA0,115200 mtdparts=hinand:1M(boot),1M(env),4M(kernel),7M(rootfs),16M(work),24M(www),6M(fw),3M(log),2M(config),64M(data) ip=10.20.9.110:10.20.9.77:10.20.0.20:255.255.0.0:hi3516d_hi::off nfsroot=10.20.9.77:/home/thkim/build_h3516d_ptz_rel/target ethaddr=4A:A4:14:6E:F8:F7
ver=U-Boot 2010.06 (Feb 06 2018 - 11:07:28)
this is the error while booting(last rows) :
IP-Config: Complete:
device=eth0, addr=10.20.9.110, mask=255.255.0.0, gw=10.20.0.20
host=hi3516d_hi, domain=, nis-domain=(none)
bootserver=10.20.9.77, rootserver=10.20.9.77, rootpath=
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "nfs" or unknown-block(2,0): error -6
Please append a correct "root=" boot option; here are the available partitions:
f000 1024 romblock0 (driver?)
1f00 1024 mtdblock0 (driver?)
f001 1024 romblock1 (driver?)
1f01 1024 mtdblock1 (driver?)
f002 4096 romblock2 (driver?)
1f02 4096 mtdblock2 (driver?)
f003 7168 romblock3 (driver?)
1f03 7168 mtdblock3 (driver?)
f004 16384 romblock4 (driver?)
1f04 16384 mtdblock4 (driver?)
f005 24576 romblock5 (driver?)
1f05 24576 mtdblock5 (driver?)
f006 6144 romblock6 (driver?)
1f06 6144 mtdblock6 (driver?)
f007 3072 romblock7 (driver?)
1f07 3072 mtdblock7 (driver?)
f008 2048 romblock8 (driver?)
1f08 2048 mtdblock8 (driver?)
f009 65536 romblock9 (driver?)
1f09 65536 mtdblock9 (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
I can't know what is the problem...
Can anyone help me ??
Thanks a lot !

Answer 1

This problem is solved.
It was simply a problem because NFS Protocol v2 was disabled.
After activating Protocol v2 of NFS Kernel Server, I confirmed that it is mounted normally.
And I heard this site is for code and programming so I will ask another site(unix.stackexchange.com) when I have a problem like this.
Thanks a lot!