On Mon, Mar 12, 2012 at 10:32:21AM -0300, Eduardo Habkost wrote:
On Mon, Mar 12, 2012 at 03:15:32PM +0200, Gleb Natapov wrote:
On Mon, Mar 12, 2012 at 01:04:19PM +0000, Daniel P. Berrange wrote:
On Mon, Mar 12, 2012 at 09:52:27AM -0300, Eduardo Habkost wrote:
On Sun, Mar 11, 2012 at 09:12:58AM -0500, Anthony Liguori wrote:
On 03/11/2012 08:27 AM, Gleb Natapov wrote:
On Sat, Mar 10, 2012 at 12:24:47PM -0600, Anthony Liguori wrote: >Let's step back here. > >Why are you writing these patches? It's probably not because you >have a desire to say -cpu Westmere when you run QEMU on your laptop. >I'd wager to say that no human has ever done that or that if they >had, they did so by accident because they read documentation and >thought they had to.
No, it's because libvirt doesn't handle all the tiny small details involved in specifying a CPU. All libvirty knows about are a set of CPU flag bits, but it knows nothing about 'level', 'family', and 'xlevel', but we would like to allow it to expose a Westmere-like CPU to the guest.
This is easily fixable in libvirt - so for the point of going discussion, IMHO, we can assume libvirt will support level, family, xlevel, etc.
And fill in all cpuid leafs by querying /dev/kvm when needed or, if TCG is used, replicating QEMU logic? And since QEMU should be usable without libvirt the same logic should be implemented in QEMU anyway.
To implement this properly, libvirt will need a proper probing interface to know what exactly is available and can be enabled. I plan to implement that.
I am have no problem in giving to libvirt the power to shoot itself in the foot. I believe libvirt developers can handle that. I have a problem with requiring every user (human or machine) to handle a weapon that can shoot their foot (that means, requiring the user to write the CPU model definition from scratch, or requiring the user to blindly copy&paste the default config file).
You are dangerous person Eduardo! -- Gleb.