Messages in this thread | | | Date | Tue, 24 Mar 2020 16:16:28 +0100 | From | Roger Pau Monné <> | Subject | Re: [PATCH 2/2] xen: enable BALLOON_MEMORY_HOTPLUG by default |
| |
On Tue, Mar 24, 2020 at 04:09:35PM +0100, Jürgen Groß wrote: > On 24.03.20 16:00, Roger Pau Monne wrote: > > Without it a PVH dom0 is mostly useless, as it would balloon down huge > > amounts of RAM in order get physical address space to map foreign > > memory and grants, ultimately leading to an out of memory situation. > > > > Such option is also needed for HVM or PVH driver domains, since they > > also require mapping grants into physical memory regions. > > > > Suggested-by: Ian Jackson <ian.jackson@eu.citrix.com> > > Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> > > --- > > Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> > > Cc: Juergen Gross <jgross@suse.com> > > Cc: Stefano Stabellini <sstabellini@kernel.org> > > Cc: xen-devel@lists.xenproject.org > > --- > > drivers/xen/Kconfig | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig > > index 57ddd6f4b729..c344bcffd89d 100644 > > --- a/drivers/xen/Kconfig > > +++ b/drivers/xen/Kconfig > > @@ -13,6 +13,7 @@ config XEN_BALLOON > > config XEN_BALLOON_MEMORY_HOTPLUG > > bool "Memory hotplug support for Xen balloon driver" > > depends on XEN_BALLOON && MEMORY_HOTPLUG > > + default y > > help > > Memory hotplug support for Xen balloon driver allows expanding memory > > available for the system above limit declared at system startup. > > > > Another variant would be to set: default XEN_BACKEND > > This would match the reasoning for switching it on.
I would rather have it always on if possible, as gntdev or privcmd (when used to map foreign pages from user-space) will also require it, and they are not gated on XEN_BACKEND AFAICT.
> Either way would be fine with me, so you can add > > Reviewed-by: Juergen Gross <jgross@suse.com>
Thanks!
Roger.
| |