Re: [Qemu-devel] [PATCH v6 0/8] ARM virt: ACPI memory hotplug support

[Shameerali Kolothum Thodi]

> -----Original Message-----
> From: Auger Eric [mailto:address@hidden]
> Sent: 02 July 2019 13:00
> To: Peter Maydell <address@hidden>; Igor Mammedov
> <address@hidden>
> Cc: Shameerali Kolothum Thodi <address@hidden>;
> QEMU Developers <address@hidden>; qemu-arm
> <address@hidden>; Samuel Ortiz <address@hidden>; Ard
> Biesheuvel <address@hidden>; Linuxarm <address@hidden>;
> xuwei (O) <address@hidden>; Shannon Zhao
> <address@hidden>; address@hidden; Laszlo Ersek
> <address@hidden>; Dr. David Alan Gilbert <address@hidden>
> Subject: Re: [Qemu-devel] [PATCH v6 0/8] ARM virt: ACPI memory hotplug
> support
> 
> Hi Peter,
> 
> On 7/2/19 1:46 PM, Peter Maydell wrote:
> > On Tue, 2 Jul 2019 at 12:07, Igor Mammedov <address@hidden>
> wrote:
> >>
> >> On Tue, 25 Jun 2019 13:14:13 +0100
> >> Shameer Kolothum <address@hidden> wrote:
> >>
> >>> This series is an attempt to provide device memory hotplug support
> >>> on ARM virt platform. This is based on Eric's recent works here[1]
> >>> and carries some of the pc-dimm related patches dropped from his
> >>> series.
> >>>
> >>> The kernel support for arm64 memory hot add was added recently by
> >>> Robin and hence the guest kernel should be => 5.0-rc1.
> >>>
> >>> NVDIM support is not included currently as we still have an unresolved
> >>> issue while hot adding NVDIMM[2]. However NVDIMM cold plug patches
> >>> can be included, but not done for now, for keeping it simple.
> >>>
> >>> This makes use of GED device to sent hotplug ACPI events to the
> >>> Guest. GED code is based on Nemu. Thanks to the efforts of Samuel and
> >>> Sebastien to add the hardware-reduced support to Nemu using GED
> >>> device[3]. (Please shout if I got the author/signed-off wrong for
> >>> those patches or missed any names).
> >>>
> >>> This is sanity tested on a HiSilicon ARM64 platform and appreciate
> >>> any further testing.
> >>
> >> There are several things I'd fix/amend but it's nothing that couldn't
> >> be done on top as bugfixes (I'll comment later on specific issues).
> >>
> >> However as a whole from ACPI and memory hotplug POV series looks more
> >> or less ready for merging.
> >>
> >> I've asked Eric to test migration (I'm quite not sure about that part),
> >> (CCed David)so on condition it works:
> >>
> >>   Reviewed-by: Igor Mammedov <address@hidden>
> >
> > If we want to get this into 4.1 I'll need somebody to do a respin
> > with all the relevant fixes pretty soon (ie within a day or two,
> > and that is pushing it because really it's missed the freeze
> > deadline already). It might be easier just to let it go into 4.2
> > instead...
> 
> OK so after those late attempts to get it in, I agree with you. If it
> missed the deadline already then let's stick to the process and try to
> get this just after 4.1.
> 
> I have just checked migration and it fails between a qemu 4.1 and qemu
> 4.0 with

Thanks Eric for verifying that. I didn’t attempt migration test with different
versions.

> "qemu-system-aarch64: Unknown savevm section or instance 'acpi-ged' 0.
> Make sure that your current VM setup matches your saved VM setup,
> including any hotplugged devices
> qemu-system-aarch64: load of migration failed: Invalid argument"
> 
> so we would need to have a no_acpi_dev class field to avoid using the
> GED device < 4.1 I think.

Ok. 

> 
> + troubles with the DSDT ref files / bios-tables-test.c to be fixed.

I am on travel at the moment and not in a position to respin this quickly.
So as suggested above will target 4.2 if that’s fine.

Thanks,
Shameer

 
> Thanks
> 
> Eric
> >
> > thanks
> > -- PMM
> >