[PATCH v3 0/9] arm/arm64: KVM: dynamic VGIC sizing

[marc.zyngier@arm.com (Marc Zyngier)]

So far, the VGIC data structures have been statically sized, meaning
that we always have to support more interrupts than we actually want,
and more CPU interfaces than we should. This is a waste of resource,
and is the kind of things that should be tuneable.

This series addresses that issue by changing the data structures to be
dynamically allocated, and adds a new configuration attribute to
allocate the number of interrupts. When the attribute is not used, we
fallback to the old behaviour of allocating a fixed number of
interrupts.

The last patch of the series is a bit out of context, but tends to fit
well here code-wise. It solves an interesting issue having to do with
the placement of the GICV interface in Stage-2 when using 64k pages
(if the HW is not 64k aligned, we need to tell userspace about the
"sub-page offset" so it can correctly place the guest's GICC
region). This allows (together with the right userspace fix) to
correctly boot a guest on a 64k host kernel on a Juno platform.

This series is also the base for Andre Przywara's GICv3 distributor
emulation code (which can support far more than 8 vcpus and 1020
interrupts).

This has been tested on both ARM (TC2) and arm64 (model and Juno).

* From v2 [2]
  - Fixed bug that broke QEMU (register access can trigger allocation)
  - irq_pending_on_cpu is now dynamic (needed for more than 32 or 64 vcpus)
  - Rebased on top of Victor's BE patches

* From v1 [1]
  - Rebased on top of 3.16-rc1
  - Lots of cleanup
  
[1]: https://lists.cs.columbia.edu/pipermail/kvmarm/2013-October/005879.html
[2]: https://lists.cs.columbia.edu/pipermail/kvmarm/2014-June/010050.html

Marc Zyngier (9):
  KVM: ARM: vgic: plug irq injection race
  arm/arm64: KVM: vgic: switch to dynamic allocation
  arm/arm64: KVM: vgic: Parametrize VGIC_NR_SHARED_IRQS
  arm/arm64: KVM: vgic: kill VGIC_MAX_CPUS
  arm/arm64: KVM: vgic: handle out-of-range MMIO accesses
  arm/arm64: KVM: vgic: kill VGIC_NR_IRQS
  arm/arm64: KVM: vgic: delay vgic allocation until init time
  arm/arm64: KVM: vgic: make number of irqs a configurable attribute
  arm64: KVM: vgic: deal with GIC sub-page alignment

 arch/arm/include/uapi/asm/kvm.h   |   2 +
 arch/arm/kvm/arm.c                |  10 +-
 arch/arm64/include/uapi/asm/kvm.h |   2 +
 include/kvm/arm_vgic.h            |  56 +++---
 virt/kvm/arm/vgic.c               | 390 ++++++++++++++++++++++++++++++++------
 5 files changed, 368 insertions(+), 92 deletions(-)

-- 
2.0.0