[RFC PATCH v1] powerpc/prom_init: disable XIVE in Secure VM.

[Ram Pai]

On Wed, Mar 04, 2020 at 11:59:48AM +0100, Greg Kurz wrote:
> On Tue, 3 Mar 2020 10:56:45 -0800
> Ram Pai <linuxram at us.ibm.com> wrote:
> 
> > On Tue, Mar 03, 2020 at 06:45:20PM +0100, Greg Kurz wrote:
....snip.
> > > 
> > > This patch would allow at least to answer Cedric's question about
> > > kernel_irqchip=off, since this looks like the only thing needed
> > > to make it work.
> > 
> > hmm.. I am not sure. Are you saying
> > (a) patch the guest kernel to share the event queue page
> > (b) run the qemu with "kernel_irqchip=off"
> > (c) and the guest kernel with "svm=on"
> > 
> > and it should all work?
> > 
> 
> Yes.

Ok. 

(1) applied the patch which shares the EQ-page with the hypervisor.
(2) set "kernel_irqchip=off"
(3) set "ic-mode=xive"
(4) set "svm=on" on the kernel command line.
(5) no changes to the hypervisor and ultravisor.

And Boom it works!.   So you were right.


I am sending out the patch for (1) above ASAP.

Thanks,
RP