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

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 25 Jun 2019 13:14:13 +0100
Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> 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 <imammedo@redhat.com>


> Thanks,
> Shameer
> 
> [1] https://patchwork.kernel.org/cover/10837565/
> [2] https://patchwork.kernel.org/cover/10783589/
> [3] https://github.com/intel/nemu/blob/topic/virt-x86/hw/acpi/ged.c
> [4] http://lists.infradead.org/pipermail/linux-arm-kernel/2019-May/651763.html
> 
> v5 --> v6
> 
> -Addressed comments from Eric.
> -Added R-by from Eric and Igor.
> 
> v4 --> v5
> -Removed gsi/ged-irq routing in virt.
> -Added Migration support.
> -Dropped support for DT coldplug case based on the discussions
>  here[4]
> -Added system_powerdown support through GED.
> 
> v3 --> v4
> Addressed comments from Igor and Eric,
> -Renamed "virt-acpi" to "acpi-ged".
> -Changed ged device parent to TYPE_DEVICE.
> -Introduced DT memory node property "hotpluggable" to resolve device
>  memory being treated as early boot memory issue(patch #7).
> -Combined patches #3 and #9 from v3 into #3.
> 
> v2 --> v3
> 
> Addressed comments from Igor and Eric,
> -Made virt acpi device platform independent and moved
>  to hw/acpi/generic_event_device.c
> -Moved ged specific code into hw/acpi/generic_event_device.c
> -Introduced an opt-in feature "fdt" to resolve device-memory being
>  treated as early boot memory.
> -Dropped patch #1 from v2.
> 
> RFC --> v2
> 
> -Use GED device instead of GPIO for ACPI hotplug events.
> -Removed NVDIMM support for now.
> -Includes dropped patches from Eric's v9 series.
> 
> Eric Auger (1):
>   hw/arm/virt: Add memory hotplug framework
> 
> Samuel Ortiz (2):
>   hw/acpi: Do not create memory hotplug method when handler is not
>     defined
>   hw/acpi: Add ACPI Generic Event Device Support
> 
> Shameer Kolothum (5):
>   hw/acpi: Make ACPI IO address space configurable
>   hw/arm/virt: Enable device memory cold/hot plug with ACPI boot
>   hw/arm/virt-acpi-build: Add PC-DIMM in SRAT
>   hw/acpi: Add system power down support to GED
>   hw/arm: Use GED for system_powerdown event
> 
>  hw/acpi/Kconfig                        |   4 +
>  hw/acpi/Makefile.objs                  |   1 +
>  hw/acpi/generic_event_device.c         | 352 +++++++++++++++++++++++++
>  hw/acpi/memory_hotplug.c               |  35 +--
>  hw/arm/Kconfig                         |   4 +
>  hw/arm/virt-acpi-build.c               |  58 ++--
>  hw/arm/virt.c                          |  88 ++++++-
>  hw/i386/acpi-build.c                   |   3 +-
>  include/hw/acpi/generic_event_device.h | 106 ++++++++
>  include/hw/acpi/memory_hotplug.h       |   9 +-
>  include/hw/arm/virt.h                  |   3 +
>  11 files changed, 607 insertions(+), 56 deletions(-)
>  create mode 100644 hw/acpi/generic_event_device.c
>  create mode 100644 include/hw/acpi/generic_event_device.h
>