This page describes building a new kernel based on upstream sources.
Who needs this page?
If you just want to apply some configuration changes or patches to a kernel that is already in Debian, following other guides such as HowToRebuildAnOfficialDebianKernelPackage should be much easier.
You only need this page if, for example, you need functionality not provided by the newest kernel already packaged for Debian.
See also HowToRebuildAnOfficialDebianKernelPackage, which despite its name, seems to address similar problems.
What to do
The authoritative source on information on building Debian kernels is the Kernel Handbook. The relevant section is https://kernel-team.pages.debian.net/kernel-handbook/ch-common-tasks.html#s-kernel-org-package .
Verifying the signature
Verifying the signature fails for me - not sure how I should get hold of the public key. Installing various -keyring packages did not help:
arnouten@jaga:~/dev/kernel$ gpg --verify linux-2.6.34.tar.bz2.sign gpg: Signature made Sun 16 May 2010 11:43:56 PM CEST using DSA key ID 517D0F0E gpg: Can't check signature: public key not found
hint: you need to import key (517D0F0E) before:
$ gpg --recv-keys 517D0F0E gpg: requesting key 517D0F0E from hkp server keys.gnupg.net gpg: key 517D0F0E: public key "Linux Kernel Archives Verification Key <email@example.com>" imported gpg: 3 marginal(s) needed, 1 complete(s) needed, PGP trust model gpg: depth: 0 valid: 2 signed: 1 trust: 0-, 0q, 0n, 0m, 0f, 2u gpg: depth: 1 valid: 1 signed: 1 trust: 0-, 0q, 0n, 0m, 1f, 0u gpg: depth: 2 valid: 1 signed: 0 trust: 1-, 0q, 0n, 0m, 0f, 0u gpg: Total number processed: 1 gpg: imported: 1
To get a good starting point for the configuration, it is convenient to take a configuration from a previous kernel version (cp /boot/config-... ./.config), and then run make oldconfig. This will create a configuration for the newer kernel, taking defaults from the configuration for the old kernel you provided. It will prompt you for any new options - usually I just follow the default.
Building the kernel
You may now follow the procedure as described in the handbook in https://kernel-team.pages.debian.net/kernel-handbook/ch-common-tasks.html#s-common-building