Re: [PATCH REPOST v3 78/80] hostmem: fix strict bind policy

[Igor Mammedov]

On Fri, 24 Jan 2020 20:17:48 +0100
Halil Pasic <address@hidden> wrote:

> On Thu, 23 Jan 2020 12:38:43 +0100
> Igor Mammedov <address@hidden> wrote:
> 
> > With main RAM now converted to hostmem backends, there is no
> > point in keeping global mem_prealloc around, so alias
> >  -mem-prealloc to "memory-backend.prealloc=on"
> > machine compat[*] property and make mem_prealloc a local
> > variable to only stir registration of compat property.
> > 
> > *) currently user accessible -global works only with DEVICE
> >    based objects and extra work is needed to make it work
> >    with hostmem backends. But that is convenience option
> >    and out of scope of this already huge refactoring.
> >    Hence machine compat properties were used.  
> 
> AFAIU because of this something like
> -global memory-backend-file.share=on
> (as proposed by
> https://lists.nongnu.org/archive/html/qemu-devel/2019-12/msg00531.html)
> can not be used to make the main RAM shared (e.g. for vhost on s390x).
> Or am I wrong? If not, is -global still the way we want to make this work
> for non-numa machines, or did I miss updates?

one should be able to use memory-backend property to make it work
instead of -m convenience option in s390 case.

As for -global for objects (or more limited variant for memory-backends),
it needs more work to support objects. (that's mostly policy decision)

> Regards,
> Halil
>