[PATCH 1/6] KVM: PPC: Book3S HV: XIVE: initialize private pointer when VPs are allocated

[Paul Mackerras]

On Mon, Sep 23, 2019 at 05:43:37PM +0200, Greg Kurz wrote:
> From: Cédric Le Goater <clg at kaod.org>
> 
> Do not assign the device private pointer before making sure the XIVE
> VPs are allocated in OPAL and test pointer validity when releasing
> the device.
> 
> Fixes: 5422e95103cf ("KVM: PPC: Book3S HV: XIVE: Replace the 'destroy' method by a 'release' method")
> Signed-off-by: Cédric Le Goater <clg at kaod.org>
> Signed-off-by: Greg Kurz <groug at kaod.org>

What happens in the case where the OPAL allocation fails?  Does the
host crash, or hang, or leak resources?  I presume that users can
trigger the allocation failure just by starting a suitably large
number of guests - is that right?  Is there an easier way?  I'm trying
to work out whether this is urgently needed in 5.4 and the stable
trees or not.

Paul.