Ramdisk modification problem

Hello,

I want to do some modifications inside the ramdisk.img that is provided in compressed mode. However, even without any modification, and by just decompress/compress the ramdisk, it won't be loaded by the following error:

[   12.780870] RAMDISK: gzip image found at block 0
[   12.821585] mmc_host mmc1: Bus speed (slot 0) = 148500000Hz (slot req 150000000Hz, actual 148500000HZ div = 0)
[   12.828018] RAMDISK: incomplete write (7019 != 26699)
[   12.828468] write error

I'm using the following commands:

decompress:

zcat kernel/ramdisk.img | cpio -idmv

compress:

find . | cpio --quiet -H newc -o | gzip -9 -n > ../ramdisk.img