页次： 1
我是学嵌入式开发的新手，我的开发板是三星s5p6818，上位机配置nfs根文件系统，但下位机内核启动后始终挂载不上，下面是挂在时候的输出：
```
[ 130.285000] swapper/0 D c067adec 0 1 0 0x00000000
[ 172.576000] VFS: Unable to mount root fs via NFS, trying floppy.
[ 172.577000] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
[ 172.578000] [<c0014e80>] (unwind_backtrace+0x0/0x138) from [<c06737e4>] (panic+0x8c/0x1e4)
[ 172.579000] [<c06737e4>] (panic+0x8c/0x1e4) from [<c0949d00>] (mount_block_root+0x174/0x220)
[ 172.580000] [<c0949d00>] (mount_block_root+0x174/0x220) from [<c0949ea0>] (mount_root+0xf4/0x114)
[ 172.581000] [<c0949ea0>] (mount_root+0xf4/0x114) from [<c0949fec>] (prepare_namespace+0x12c/0x18c)
[ 172.582000] [<c0949fec>] (prepare_namespace+0x12c/0x18c) from [<c09499bc>] (kernel_init+0x180/0x1c0)
[ 172.583000] [<c09499bc>] (kernel_init+0x180/0x1c0) from [<c000f7a4>] (kernel_thread_exit+0x0/0x8)
[ 172.584000] Rebooting in 5 seconds..
[ 182.665000] Restarting Linux version 3.4.39-9tripod (charles@jindouyun) (gcc version 4.7.4 20131111 (prerelease) (crosstool-NG linaro-1.13.1-4.8-2013.11 - nexell) ) #2 SMP PREEMPT Thu Apr 4 11:26:07 CST 2019
[ 182.665000]
[ 182.666000] system reset: I2C_WriteBit CLK Timeout Arbitration Fail
```
我的uboot上设置的参数
```
Hi# print
baudrate=115200
bootargs=root=/dev/nfs nfsroot=192.168.1.8:/srv/rootfs ip=192.168.1.110:192.168.1.8:192.168.1.1:255.255.255.0::eth0:off noinitrd console=ttySAC0,115200 maxcpus=1 lcd=wy070ml tp=gslx680-linux
bootcmd=tftp 0x48000000 uImage ; bootm 0x48000000
bootdelay=3
bootfile=uImage
ethact=dwmac.c0060000
ethaddr=00:e2:1c:ba:e8:60
ethprime=RTL8211
fastboot=flash=mmc,2:ubootpak:2nd:0x200,0x78000;flash=mmc,2:2ndboot:2nd:0x200,0x4000;flash=mmc,2:bootloader:boot:0x8000,0x70000;flash=mmc,2:boot:ext4:0x00100000,0x04000000;flash=mmc,2:system:ext4:0x04100000,0x2F200000;flash=mmc,2:cache:ext4:0x33300000,0x1AC00000;flash=mmc,2:misc:emmc:0x4E000000,0x00800000;flash=mmc,2:recovery:emmc:0x4E900000,0x01600000;flash=mmc,2:userdata:ext4:0x50000000,0x0;
fileaddr=48000000
filesize=5fb0c
gatewayip=192.168.1.1
ipaddr=192.168.1.110
netmask=255.255.255.0
serverip=192.168.1.8
stderr=serial
stdin=serial
stdout=serial
```
下面是nfs的配置
```
/etc/exports
/srv/rootfs *(rw,sync,no_root_squash,no_subtree_check)
```
离线
页次： 1