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

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 03.07.13 at 14:07, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
> The idea of the patch was that anyway Device(HPET) is disabled in the
> ACPI table if the hpet is disabled.  But if old Linux guests cannot cope
> with this, too bad...

The thing is that HPET is needed / gets set up by Linux (and likely
by other OSes too) long before ACPI CA is ready to parse the
DSDT. In fact I don't think Linux even looks at the DSDT object in
order to determine whether HPET is usable (and as per the spec
the intention anyway is to have these objects mainly/exclusively
for secondary HPETs, not the primary one replacing 8254/RTC).

Jan


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