[forgeman]

You can check the consistency of the kernel "file" and compare a MD5 / SHA-1 of known good kernel. Assumption here that the kernel is loaded into healthy hardware. Depends on the spirit of the question. I do agree, running kernel looking at itself... chicken::egg.

[gcr]

For corruption, sure, but rootkits can mess that up by changing the md5 binary to always give the tainted kernel a known checksum.

If a malicious attacker can modify a kernel, no process running within the kernel can check it for consistency.