[PATCH v2 2/3] KVM: PPC: Book3S HV: Don't push XIVE context when not using XIVE device

[Michael Ellerman]

On Tue, 2019-08-13 at 10:01:00 UTC, Paul Mackerras wrote:
> At present, when running a guest on POWER9 using HV KVM but not using
> an in-kernel interrupt controller (XICS or XIVE), for example if QEMU
> is run with the kernel_irqchip=off option, the guest entry code goes
> ahead and tries to load the guest context into the XIVE hardware, even
> though no context has been set up.
> 
> To fix this, we check that the "CAM word" is non-zero before pushing
> it to the hardware.  The CAM word is initialized to a non-zero value
> in kvmppc_xive_connect_vcpu() and kvmppc_xive_native_connect_vcpu(),
> and is now cleared in kvmppc_xive_{,native_}cleanup_vcpu.
> 
> Cc: stable at vger.kernel.org # v4.11+
> Reported-by: Cédric Le Goater <clg at kaod.org>
> Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
> Signed-off-by: Paul Mackerras <paulus at ozlabs.org>
> Reviewed-by: Cédric Le Goater <clg at kaod.org>

Applied to powerpc topic/ppc-kvm, thanks.

https://git.kernel.org/powerpc/c/8d4ba9c931bc384bcc6889a43915aaaf19d3e499

cheers