Question

# md5sum /data/test.ko 
md5sum: can't read '/data/test.ko': Input/output error

Reproduction

1. Push nfs.ko to rootfs and confirm it is OK in normal system

adb push nfs.ko /data/

# md5sum /data/nfs.ko
5c566793a4fa8e5c661baffc40356041  /data/nfs.ko

2. Enter recovery system and copy specified ko to another name

# recovery

[...]

# md5sum /data/nfs.ko
5c566793a4fa8e5c661baffc40356041  /data/nfs.ko
# cp /data/nfs.ko /data/test.ko
# md5sum /data/test.ko 
5c566793a4fa8e5c661baffc40356041  /data/test.ko

3. reboot to normal system

# md5sum /data/test.ko 
md5sum: can't read '/data/test.ko': Input/output error

Answer

Disable LZO support for jffs2

-CONFIG_JFFS2_LZO=y
+# CONFIG_JFFS2_LZO is not set

TODO

Add a warning on mounting incompatible jffs partition.