On Thu, 16 Jan 2020 11:42:09 +0100
Michal Privoznik <mprivozn(a)redhat.com> 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> 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>
>>> ---
>>> 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.
*) I might give another try to removing 'mem' completely in migration
compatible manner but that's well beyond the scope of this series
So far I hasn't been able to convince myself that previous attempts
to do it were absolutely correct for all corner cases that are there.
Michal