Re: [libvirt] [PATCH v2 82/86] numa: forbid '-numa node, mem' for 5.0 and newer machine types

On Thu, 16 Jan 2020 11:42:09 +0100 Michal Privoznik <mprivozn(a)redhat.com&gt; wrote: > On 1/15/20 5:52 PM, Igor Mammedov wrote: > > On Wed, 15 Jan 2020 16:34:53 +0100 > > Peter Krempa <pkrempa(a)redhat.com&gt; wrote: > > > >> On Wed, Jan 15, 2020 at 16:07:37 +0100, Igor Mammedov wrote: > >>> Deprecation period is ran out and it's a time to flip the switch > >>> introduced by cd5ff8333a. > >>> Disable legacy option for new machine types and amend documentation. > >>> > >>> Signed-off-by: Igor Mammedov <imammedo(a)redhat.com&gt; > >>> --- > >>> CC: peter.maydell(a)linaro.org > >>> CC: ehabkost(a)redhat.com > >>> CC: marcel.apfelbaum(a)gmail.com > >>> CC: mst(a)redhat.com > >>> CC: pbonzini(a)redhat.com > >>> CC: rth(a)twiddle.net > >>> CC: david(a)gibson.dropbear.id.au > >>> CC: libvir-list(a)redhat.com > >>> CC: qemu-arm(a)nongnu.org > >>> CC: qemu-ppc(a)nongnu.org > >>> --- > >>> hw/arm/virt.c | 2 +- > >>> hw/core/numa.c | 6 ++++++ > >>> hw/i386/pc.c | 1 - > >>> hw/i386/pc_piix.c | 1 + > >>> hw/i386/pc_q35.c | 1 + > >>> hw/ppc/spapr.c | 2 +- > >>> qemu-deprecated.texi | 16 ---------------- > >>> qemu-options.hx | 8 ++++---- > >>> 8 files changed, 14 insertions(+), 23 deletions(-) > >> > >> I'm afraid nobody bothered to fix it yet: > >> > >> https://bugzilla.redhat.com/show_bug.cgi?id=1783355 > > > > It's time to start working on it :) > > (looks like just deprecating stuff isn't sufficient motivation, > > maybe actual switch flipping would work out better) > > > > So how was the upgrade from older to newer version resolved? I mean, if > the old qemu used -numa node,mem=XXX and it is migrated to a host with > newer qemu, the cmd line can't be switched to -numa node,memdev=node0, > can it? I'm asking because I've just started working on this. see commit cd5ff8333a3c87 for detailed info. Short answer is it's not really resolved [*], -numa node,mem will keep working on newer QEMU but only for old machine types new machine types will accept only -numa node,memdev. One can check if "mem=' is supported by using QAPI query-machines and checking numa-mem-supported field. That field is flipped to false for 5.0 and later machine types in this patch.