Re: [Qemu-arm] [PATCH v4 0/7] q35: add negotiable broadcast SMI

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Dec 01, 2016 at 06:06:17PM +0100, Laszlo Ersek wrote:
> * This is version 4 of the series; the last version was at
>   <http://lists.nongnu.org/archive/html/qemu-devel/2016-11/msg03582.html>.
> 
>   This version is practically a rewrite from scratch, seeking to address
>   the v3 feedback. Here's what the individual patches do:
> 
>   - Patch #1 rebases and extends Michael's "writeable fw_cfg blobs"
>     patch from Feb/March 2016. The changes relative to the original
>     patch are documented in the commit message (the code changes are
>     minimal).
> 
>   - Patches #2 and #3 turn the FW_CFG_FILE_SLOTS constant into a device
>     property, and expose the desired number of fw_cfg file slots to
>     board code. This is meant to address a concern raised by Paolo in
>     the v2 review
>     <http://lists.nongnu.org/archive/html/qemu-devel/2016-11/msg03125.html>,
>     namely that we're about to run out of FW_CFG_FILE_SLOTS.
> 
>   - Patch #4 introduces the "pc-q35-2.9" and "pc-i440fx-2.9" machine
>     types, which are allowed to take advantage of the new default for
>     fw_cfg file slots (0x20 rather than 0x10).
> 
>   - Patch #5 introduces SMI feature negotiation via fw_cfg, with the
>     following new files:
> 
>     - etc/smi/host-features
>     - etc/smi/guest-features
>     - etc/smi/features-ok
> 
>     This is supposed to follow Michael's recommendation re: imitating
>     virtio
>     <http://lists.nongnu.org/archive/html/qemu-devel/2016-11/msg03218.html>.
> 
>     The guest-features file is freely writeable by the guest (no write
>     callbacks in fw_cfg), and the feature validation & lockdown occurs
>     when the guest selects the features-ok file (for reading).
> 
>     Board code is allowed to choose the host feature bitmap to
>     advertise.
> 
>     This patch doesn't add any specific SMI features yet.
> 
>   - Patch #6 adds the ICH9_LPC_SMI_F_BROADCAST feature.
> 
>   - Patch #7 introduces the PCMachineClass.get_smi_host_features method,
>     and implements it for "pc-q35-2.9" and later. The idea is to tie the
>     SMI host features to machine types, and let the machine types
>     calculate their host features with code (i.e., not just a constant).
> 
>     In this patch, the "pc-q35-2.9" machine type exposes the
>     ICH9_LPC_SMI_F_BROADCAST feature iff (smp_cpus == max_cpus), that
>     is, when VCPU hotplug is not possible. (Also from Paolo's v3
>     feedback, in
>     <http://lists.nongnu.org/archive/html/qemu-devel/2016-11/msg04919.html>.)
> 
> * I've written the OVMF side patches too and tested them together
>   (including gdb / debug messages for "white box" testing).
> 
> * Note that this version depends on the following PULL req from Michael:
> 
>   [Qemu-devel] [PULL 0/5] virtio, vhost, pc: fixes
>   http://lists.nongnu.org/archive/html/qemu-devel/2016-11/msg05503.html
> 
>   In particular on the following patch:
>   "loader: fix handling of custom address spaces when adding ROM blobs"
> 
> Cc: "Gabriel L. Somlo" <somlo@cmu.edu>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> Cc: Igor Mammedov <imammedo@redhat.com>
> Cc: Michael Walle <michael@walle.cc>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> Cc: Shannon Zhao <zhaoshenglong@huawei.com>
> Cc: qemu-arm@nongnu.org
> 
> Thanks
> Laszlo

So I reviewed fw cfg stuff, looks good to me. I'd prefer Paolo to review
and merge broadcast SMI stuff as appropriate.  Paolo, makes sense?


> Laszlo Ersek (6):
>   fw-cfg: turn FW_CFG_FILE_SLOTS into a device property
>   fw-cfg: expose "file_slots" parameter in fw_cfg_init_io_dma()
>   hw/i386/pc: introduce 2.9 machine types with 0x20 fw_cfg file slots
>   hw/isa/lpc_ich9: add SMI feature negotiation via fw_cfg
>   hw/isa/lpc_ich9: add broadcast SMI feature
>   hw/i386/pc_q35: advertise broadcast SMI if VCPU hotplug is turned off
> 
> Michael S. Tsirkin (1):
>   fw-cfg: support writeable blobs
> 
>  docs/specs/fw_cfg.txt          |  36 +++++++++---
>  hw/lm32/lm32_hwsetup.h         |   2 +-
>  include/hw/compat.h            |  11 ++++
>  include/hw/i386/ich9.h         |  15 ++++-
>  include/hw/i386/pc.h           |   4 ++
>  include/hw/loader.h            |   7 ++-
>  include/hw/nvram/fw_cfg.h      |   5 +-
>  include/hw/nvram/fw_cfg_keys.h |   7 ++-
>  hw/arm/virt-acpi-build.c       |   2 +-
>  hw/core/loader.c               |  18 +++---
>  hw/i386/acpi-build.c           |   4 +-
>  hw/i386/pc.c                   |   3 +-
>  hw/i386/pc_piix.c              |  16 +++++-
>  hw/i386/pc_q35.c               |  37 ++++++++++++-
>  hw/isa/lpc_ich9.c              |  92 +++++++++++++++++++++++++++++-
>  hw/nvram/fw_cfg.c              | 123 +++++++++++++++++++++++++++++++++++------
>  16 files changed, 326 insertions(+), 56 deletions(-)
> 
> -- 
> 2.9.2