building a kernel from a mounted partition

[Andy Johnson]

Hello,
I have a dual boot machine, Ubuntu/Fedora.
I have a kernel tree on the fedora partition.
Now, I had build a kernel on the Fedora partition successfully.

 I did **not** change anything in the tree, and then

When I boot into Ubuntu and mount the fedora partition, and
go there and run "make" , it builds ** all **  the tree again ! any I
idea why ?

And after the build on Ubuntu is over successfully, if I boot into
Fedora again and run make, it **again** builds all the tree.

Is there a way to avoid this ?

rgs
Andy