I have built 4.0.2-rc6 for F14 which is (temporarily) at
and 4.1.1-rc2 for F15 which is (temporarily) at
these are supposedly the final release candidates before full releases in
a week's time, but that could change.
If anyone doesn't know already, the upstream kernel tree (as of 3.0-rc1)
has xen-blkback included which means you can now run xen which reasonable
disk performance with native kernels (though there are currently issues
with module-init-tools and kernel-3.0-0.rc1.git0.1.fc16 is confused as to
whether it was 3.0 or 3.0.0).
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