x86: Correctly detect hypervisor

We try to handle the hypervisor compatibility mode by detecting hypervisor
through a specific order. This is not robust, since hypervisors may implement
each others features.

This patch tries to handle this situation by always choosing the last one in the
CPUID leaves. This is done by letting .detect() return a priority instead of
true/false and just re-using the CPUID leaf where the signature were found as
the priority (or 1 if it was found by DMI). Then we can just pick hypervisor who
has the highest priority. Other sophisticated detection method could also be
implemented on top.

Suggested by H. Peter Anvin and Paolo Bonzini.

Acked-by: K. Y. Srinivasan <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Cc: Doug Covelli <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dan Hecht <[email protected]>
Cc: Paul Gortmaker <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Gleb Natapov <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Signed-off-by: Jason Wang <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>

0 files changed, 0 insertions, 0 deletions