this one contains various small documentation updates and updates to xconfig,
but the important parts (and the smallest part of the actual patch) are:

 - shared file lockup fix by Stephen Tweedie
 - my fix for the TCP bug that Ingo found
 - Ingo's io-apic setup fixes, which should finally get rid of the
   spurious apic interrupts with some motherboards and the ExtINT setup.
 - inode leak thing
 - SMP scheduler potential race condition fix
 - sound driver updates
 - partition and disk fixes (2kB blocksize media and some IDE disk
   geometry and irq detection issues).

None of the fixes are critical to most people, but all of them _can_ be
critical to people who have seen vulnerabilities in the area. As such, if
you're happy with 2.2.1 there is no pressing reason to test this patch
out, but I hope to have the pre-patches so that the final 2.2.2 can be
left around for a while (CD-ROM manufacturers etc would certainly prefer
to not see lots of releases).

                Linus