[Xen-devel] revert commit e4fd0475 ("hvmloader: always include HPET table")

["Jan Beulich" <JBeulich@xxxxxxxx>]

Windows SVVP tests requiring a HPET ACPI table is in my opinion
not a valid reason to always expose that table - respective tests
should be run with "hpet=1" in the guest config file.

The problem here is that at least with qemu-traditional, which
by default doesn't appear to emulate a HPET, the advertising
here can mislead an OS to believe that there actually is a usable
HPET, which isn't true when neither Xen nor qemu emulate one.
This ie being observed in reality: SLES9, being 2.6.5 based,
doesn't have enough checking to notice that the HPET doesn't
actually work.

In fact, we may want to have an inverse mode (like a lot of
hardware used to behave earlier on): A functional HPET that
isn't exposed in ACPI tables, but that an OS knowing enough
about the chipset can nevertheless find and use.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel