Hello,
RHEL 5.5 has been released, and it contains many Xen related fixes.
Here's the most important of the them.. fixing a dom0 caching bug which could cause domU disk corruption when the domU disk was accessed from dom0 after the domU was shutdown. Most people noticed this bug when pygrub used wrong (cached) information.
"pygrub uses cached and eventually outdated grub.conf, kernel and initrd": https://bugzilla.redhat.com/show_bug.cgi?id=466681
And some more:
"Xen hypervisor doesn't mask xsave feature from the guest; Fedora 11 PV domU kernel crashes": https://bugzilla.redhat.com/show_bug.cgi?id=524719
"[RHEL-5 Xen]: F-11 Xen 64-bit domU cannot be started with > 2047MB of memory": https://bugzilla.redhat.com/show_bug.cgi?id=502826
" Boot hang when installing HVM DomU": https://bugzilla.redhat.com/show_bug.cgi?id=524052
"[RHEL5 Xen]: PV guest crash on poweroff": https://bugzilla.redhat.com/show_bug.cgi?id=540811
"[RHEL5 Xen]: Cpu frequency scaling is broken on Intel": https://bugzilla.redhat.com/show_bug.cgi?id=553324
RHEL 5.5 kernel changelog: http://rhn.redhat.com/errata/RHSA-2010-0178.html
Work-in-progress (Not yet in 5.5):
"Grub2 guest support for RHEL5 Xen pygrub": https://bugzilla.redhat.com/show_bug.cgi?id=577511
-- Pasi