linux内核nfs挂载根文件系统失败

Question

linux内核nfs挂载根文件系统失败的log如下：

[    5.586185] VFS: Cannot open root device "nfs" or unknown-block(0,255)
[    5.592372] Please append a correct "root=" boot option; here are the available partitions:
[    5.600700] b300         3817472 mmcblk0 driver: mmcblk
[    5.605858]   b301          264759 mmcblk0p1
[    5.610103]   b302          264759 mmcblk0p2
[    5.614349]   b303          104412 mmcblk0p3
[    5.618595]   b304         3158463 mmcblk0p4
[    5.622844] b308         7761920 mmcblk1 driver: mmcblk
[    5.628057]   b309         7726620 mmcblk1p1
[    5.632288] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,255)
[    5.640837] Backtrace:
[    5.643135] [<c0034fb8>] (dump_backtrace+0x0/0x110) from [<c0501498>] (dump_stack+0x18/0x1c)
[    5.651546]  r6:00008000 r5:dfedc000 r4:c06f5b6c r3:00000002
[    5.657161] [<c0501480>] (dump_stack+0x0/0x1c) from [<c0501514>] (panic+0x78/0xf8)
[    5.664720] [<c050149c>] (panic+0x0/0xf8) from [<c0008f6c>] (mount_block_root+0x25c/0x2ac)
[    5.672949]  r3:00000002 r2:00000001 r1:dfc37f60 r0:c06464fa
[    5.678564] [<c0008d10>] (mount_block_root+0x0/0x2ac) from [<c0009010>] (mount_root+0x54/0x68)
[    5.687163] [<c0008fbc>] (mount_root+0x0/0x68) from [<c0009188>] (prepare_namespace+0x164/0x1bc)
[    5.695912]  r5:c00290cd r4:c0731740
[    5.699448] [<c0009024>] (prepare_namespace+0x0/0x1bc) from [<c00084fc>] (kernel_init+0x128/0x170)
[    5.708388]  r5:c00083d4 r4:c0731500
[    5.711931] [<c00083d4>] (kernel_init+0x0/0x170) from [<c0058894>] (do_exit+0x0/0x5f0)
[    5.719826]  r4:00000000 r3:00000000
[    5.723365] Rebooting in 5 seconds..
[   10.763051] Restarting Linux version 2.6.35.7+ (fly@fly-vm) (gcc version 4.4.1 (Sourcery G++ Lite 2009q3-67) ) #1 PREEMPT Mon Aug 9 08:31:45 CST 2021
[   10.763062]
[   10.778218] arch_reset: attempting watchdog reOK

Answer 1

busybox make menuconfig的简单配置

Busybox Settings--->

    Build Options--->

        [*]Build BusyBox as a static binary(no shared libs)



        

Busybox Library Tuning--->

    [*]vi-style line editing commands

    [*]Fancy shell prompts

    

    

Linux Module Utilities--->

    [ ]Simplified modutils

    [*]insmod

    [*]rmmod

    [*]lsmod

    [*]modprobe

    [*]depmod



    

Linux System Utilities--->[*]mdev

    [*]Support /etc/mdev.conf

    [*]Support subdirs/symlinks

    [*]Support regular expressions substitutions when renaming dev

    [*]Support command execution at device addition/removal

    [*]Support loading of firmwares