[Qemu-devel] [PATCH RFC 00/14]pc: q35: x2APIC support in kvm_apic mode

[Igor Mammedov]

Series is based on top cpu hotplug refactoring(*1),
and extends current CPU/kvm_apic/generic pc machine
code to support x2APIC and upto 288 VCPUs when QEMU
is used with KVM's lapic.

Due to FW_CFG_MAX_CPUS (which is actually apic_id_limit)
being limited to uint16_t, the max possible APIC ID is
limitted to 2^16 with this series but that should
be sufficient for bumping VCPUs number for quite a while.


git gree for testing:
https://github.com/imammedo/qemu.git x2apic_rfc

To play with the feature, one would also need
seabios counterpart:
https://github.com/imammedo/seabios.git x2apic_rfc

Radim's
[RFC 0/9] KVM: x86: break the xAPIC barrier
http://www.spinics.net/lists/kvm/msg132036.html

and Peter's IRQ remapping series.

*1)
[Qemu-devel] [RFC 00/42] ACPI CPU hotplug refactoring to support more than 255 
CPUs and PXM/OST methods
https://lists.gnu.org/archive/html/qemu-devel/2016-05/msg00033.html

Igor Mammedov (14):
  pc: acpi: x2APIC support for MADT table
  pc: acpi: x2APIC support for SRAT table
  acpi: cphp: add support for x2APIC in _MAT method
  pc: leave max apic_id_limit only in legacy cpu hotplug code
  pc: apic: move MAX_APICS check to 'apic' class
  pc: apic_common: extend APIC ID property to 32bit
  pc: apic_common: restore APIC ID to initial ID on reset
  pc: apic_common: reset APIC ID to initial ID when switching into
    x2APIC mode
  pc: kvm_apic: pass APIC ID depending on xAPIC/x2APIC mode
  pc: clarify FW_CFG_MAX_CPUS usage comment
  increase MAX_CPUMASK_BITS from 255 to 288
  pc: add 'etc/boot-cpus' fw_cfg file for machine with more than 255
    CPUs
  pc: q35: bump max_cpus to 288
  DO NOT APPLY: hack to make 2nd CPU APIC ID to be x2APIC one

 hw/acpi/cpu.c                   |   5 ++
 hw/acpi/cpu_hotplug.c           |   7 ++-
 hw/arm/virt.c                   |   2 +-
 hw/i386/acpi-build.c            | 114 +++++++++++++++++++++++++++-------------
 hw/i386/kvm/apic.c              |  12 ++++-
 hw/i386/pc.c                    |  34 ++++++------
 hw/i386/pc_piix.c               |   1 +
 hw/i386/pc_q35.c                |   1 +
 hw/intc/apic.c                  |  10 ++++
 hw/intc/apic_common.c           |  54 +++++++++++++++----
 hw/ppc/spapr.c                  |   2 +-
 include/hw/acpi/acpi-defs.h     |  32 +++++++++++
 include/hw/i386/apic_internal.h |   7 ++-
 include/sysemu/sysemu.h         |   2 +-
 target-i386/cpu.c               |   2 +-
 target-i386/cpu.h               |   1 +
 16 files changed, 212 insertions(+), 74 deletions(-)

-- 
1.8.3.1