Stop new kernel on board

Hi, Im trying to do following website

but, I can’t change new kernel

I copied zImage, u-boot.img, MLO, uEnv.txt, Root file system(small flash) and kernel files on SD card.

and I inserted it on beaglebone black board. and then power up on board.
and stop the board
what did I miss …??
the kernel compiled wrong?? (that might not be able to know U guys … ㅠ_ㅠ)
below text are serial msg.

It looks like you either picked the wrong kernel branch or broke the

Care to share some more details? (aka which kernel branch/etc)