Oh dear, seems I made it more complicated then necessary :-)
I am not using the kernel ppa like a ppa at all. Instead I regularly check http://kernel.ubuntu.com/~kernel-ppa/mainline/ and if there is a new kernel, I manually remove the old kernel and manually install the new kernel. Newer realized that I could use it like a ppa (it does not contain the same information like launchpad where you get instructions how to integrate the ppa into your system) - the tutorials to get a more recent kernel did not mention that and it was working until now.
Oh dear, seems I made it more complicated then necessary :-)
I am not using the kernel ppa like a ppa at all. Instead I regularly check http:// kernel. ubuntu. com/~kernel- ppa/mainline/ and if there is a new kernel, I manually remove the old kernel and manually install the new kernel. Newer realized that I could use it like a ppa (it does not contain the same information like launchpad where you get instructions how to integrate the ppa into your system) - the tutorials to get a more recent kernel did not mention that and it was working until now.