[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] Re: expose MWAIT to dom0



On 15/08/2011 08:13, "Tian, Kevin" <kevin.tian@xxxxxxxxx> wrote:

>> Well the problem is some older kernels will try to use MWAIT if they see the
>> feature in CPUID. Of course that doesn't work outside ring 0.
>> 
> 
> if those old kernels are still of interest, then possibly a boot option in Xen
> would
> be applausive. Or can we just allow selectively exposing MWAIT when xen
> cpuidle is enabled?

The kernel could unconditionally advertise MWAIT from its cpuid pv_ops hook?
If all that's doing is causing relevant parts of BIOS tables to be parsed,
would that be safe when MWAIT is not in fact available?

Else the kernel could get the flag from the real non paravirtualised CPUID
instruction.

 -- Keir



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.