android - adb shell mount -o remount,rw -t yaffs2 /dev/block/mtdblock0 /system Operation not permitted -

i have put command facing problem

operation not permitted

 adb shell mount -o remount,rw -t yaffs2 /dev/block/mtdblock0 /system   

and error shown

operation not permitted 

you have root remount /system.

check true id command.

i guess have permissions of user-shell

add if root - may try adb remount command. command looking for.