[PATCH v2 0/12] Hypervisor-mode KVM on POWER7

[Alexander Graf]

On 31.05.2011, at 08:40, Paul Mackerras wrote:

> The following series of patches enable KVM to exploit the hardware
> hypervisor mode on 64-bit Power ISA Book3S machines.  At present only
> POWER7 is supported, but it would be easy to add other processors.
> 
> Running the KVM host in hypervisor mode means that the guest can use
> both supervisor mode and user mode.  That means that the guest can
> execute supervisor-privilege instructions and access supervisor-
> privilege registers.  In addition the hardware directs most exceptions
> to the guest.  Thus we don't need to emulate any instructions in the
> host.  Generally, the only times we need to exit the guest are when it
> does a hypercall or when an external interrupt or host timer
> (decrementer) interrupt occurs.
> 
> The focus of this KVM implementation is to run guests that use the
> PAPR (Power Architecture Platform Requirements) paravirtualization
> interface, which is the interface supplied by PowerVM on IBM pSeries
> machines.  Currently the "pseries" machine type in qemu is only
> supported by book3s_hv KVM, and book3s_hv KVM only supports the
> "pseries" machine type.  That will hopefully change in future.
> 
> These patches are against Linus' v3.0-rc1 tree.

Thinking about the testability of this a bit more ... how much effort would it be to get this code running on a 970MP with SLOF? There should only be a few POWER7 specific pieces, right?


Alex