Root-NFS: No NFS server available, giving up.
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "192.168.1.109:/home/smile_maidou/nfs_root" or unknown-block(2,0)
Please append a correct "root=" boot option; here are the available partitions:
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
[<8002c56c>] (unwind_backtrace+0x0/0xe4) from [<802adb44>] (panic+0x68/0xe4)
[<802adb44>] (panic+0x68/0xe4) from [<80008fe4>] (mount_block_root+0x1b8/0x1f8)
[<80008fe4>] (mount_block_root+0x1b8/0x1f8) from [<80009360>] (prepare_namespace+0x160/0x1b4)
[<80009360>] (prepare_namespace+0x160/0x1b4) from [<80008c38>] (kernel_init+0x120/0x168)
[<80008c38>] (kernel_init+0x120/0x168) from [<80027f7c>] (kernel_thread_exit+0x0/0x8)