关于linux内核启动及驱动加载问题

1. 自己编写的mmc驱动程序， insmod加载该驱动成功，能正确的读写，删除， 基本功能测试没有问题
2. 在一张SD卡上建立root文件系统， 将SD卡驱动编译进内核， 通过SD卡加载文件系统， 加载总是不成功， 出现以下错误：

[   53.382712] atkbd.c: keyboard reset failed on fpga:kmi1
<6>Waiting for root device /dev/mmcblk0p4...
[   53.861013] Waiting for root device /dev/mmcblk0p4...
<3>INFO: task kmmcd:165 blocked for more than 120 seconds.
[  288.385908] INFO: task kmmcd:165 blocked for more than 120 seconds.
<3>"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  288.425467] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
<6>kmmcd           D[  288.454402] kmmcd           D<c> c02c69b4  c02c69b4 <c>    0   165      2 0x00000000
    0   165      2 0x00000000
[<c02c69b4>] (schedule+0x280/0x2c4) from [<c02c6b5c>] (schedule_timeout+0x18/0x18
[  288.508780] [<c02c69b4>] (schedule+0x280/0x2c4) from [<c02c6b5c>] (schedule_timeout+0x18/0x18
[<c02c6b5c>] (schedule_timeout+0x18/0x18 from [<c02c6628>] (wait_for_common+0xc0/0x14c)
[  288.559151] [<c02c6b5c>] (schedule_timeout+0x18/0x18 from [<c02c6628>] (wait_for_common+0xc0/0x14c)
[<c02c6628>] (wait_for_common+0xc0/0x14c) from [<c017b95c>] (mmc_wait_for_req+0x114/0x120)
[  288.611389] [<c02c6628>] (wait_for_common+0xc0/0x14c) from [<c017b95c>] (mmc_wait_for_req+0x114/0x120)
[<c017b95c>] (mmc_wait_for_req+0x114/0x120) from [<c017e1a4>] (mmc_app_send_scr+0xec/0x134)
[  288.664140] [<c017b95c>] (mmc_wait_for_req+0x114/0x120) from [<c017e1a4>] (mmc_app_send_scr+0xec/0x134)
[<c017e1a4>] (mmc_app_send_scr+0xec/0x134) from [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c)
[  288.717131] [<c017e1a4>] (mmc_app_send_scr+0xec/0x134) from [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c)
[<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c) from [<c017dd04>] (mmc_attach_sd+0x104/0x180)
[  288.769587] [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c) from [<c017dd04>] (mmc_attach_sd+0x104/0x180)
[<c017dd04>] (mmc_attach_sd+0x104/0x180) from [<c017b7bc>] (mmc_rescan+0x1b0/0x23c)
[  288.819924] [<c017dd04>] (mmc_attach_sd+0x104/0x180) from [<c017b7bc>] (mmc_rescan+0x1b0/0x23c)
[<c017b7bc>] (mmc_rescan+0x1b0/0x23c) from [<c00500ac>] (worker_thread+0x14c/0x1c4)
[  288.868745] [<c017b7bc>] (mmc_rescan+0x1b0/0x23c) from [<c00500ac>] (worker_thread+0x14c/0x1c4)
[<c00500ac>] (worker_thread+0x14c/0x1c4) from [<c0052e94>] (kthread+0x7c/0x84)
[  288.916254] [<c00500ac>] (worker_thread+0x14c/0x1c4) from [<c0052e94>] (kthread+0x7c/0x84)
[<c0052e94>] (kthread+0x7c/0x84) from [<c002a970>] (kernel_thread_exit+0x0/0x

内核版本：打了android patch的2.6.33， SD的驱动加载优先级为5

请问是什么原因？ 如何解决？ 谢谢!

本地和SD卡的环境那些区别？

没有什么区别，同一个kernel ， 同一个文件系统，  通过nfs加载文件系统的时候sd卡的driver就能正确的加载成功， 通过sd卡加载文件系统就出错