Distribution kernels
Many Linux distributions provide their own "longterm maintenance"
kernels that may or may not be based on those maintained by kernel
developers. These kernel releases are not hosted at kernel.org and
kernel developers can provide no support for them.
It is easy to tell if you are running a distribution kernel. Unless you
downloaded, compiled and installed your own version of kernel from
kernel.org, you are running a distribution kernel. To find out the
version of your kernel, run uname -r:
# uname -r
3.7.5-201.fc18.x86_64
If you see anything at all after the dash, you are running a distribution
kernel. Please use the support channels offered by your distribution
vendor to obtain kernel support.