If I upgrade my kernel, either by changing the .config file or actually doing a version upgrade, do I need to recompile all programs that depend on the kernel, which is to say -- everything ?

For instance, do I need to recompile the X-windows system?
What about wpa_supplicant? Evolution?

Kernel modules and device drivers obviously need to be recompiled,

All these programs depend on the kernel, obviously. Logically, a
change in the kernel may destabilize the programs that depend on it.
I've had a lot of instability after kernel recompiles. I wonder what the accepted
wisdom is. I'm wondering if Gentoo would be good because it would recompile
everything if I change the kernel.

Harold

in short....NO!


External drivers, for instance from nVidia would need to be reinstalled and such....but everything else wouldn't nedd to be recompiled.

You only need to recompile the kernel modules and so on, no every app that you got.

Well, why not? What's the difference between a kernel module (like ath_pci) or something like wpa_supplicant?
I've found that I do have to recompile wpa_supplicant after kernel upgrades.

That brings up an even more fearsome question. If I'm using a custom kernel, can I download packages from
debian's repositories, or do I have to compile the application myself to match my kernel ?

Harold

it's really glibc that interacts with the kernel and the other user space programms interact with glibc
the kernel is designed to have a consistent interface with glibc basically so all is good.
if you upgraded glibc then you would need to recompile everything.

That's because modules and so on is being inserted directly into the kernel, normal apps just run on top of it.

Ok, glibc makes some sense. I've also had problems when I switch from GCC 3.3 to GCC 4.0.
I assume this would change the glibc, and so all the apps would get confused and need to be
recompiled. Is that thinking correct?