On arm64 we have a static limit of 40bits of physical address space
for the VM with KVM. This series lifts the limitation and allows the
VM to configure the physical address space upto 52bit on systems
where it is supported. We retain the default and minimum size to 40bits
to avoid breaking backward compatibility.
The interface provided is an IOCTL on the VM fd. The guest can change
only increase the limit from what is already configured, to prevent
breaking the devices which may have already been configured with a
particular guest PA. The guest can issue the request until something
is actually mapped into the stage2 table (e.g, memory region or device).
This also implies that we now have per VM configuration of stage2
control registers (VTCR_EL2 bits).
The arm64 page table level helpers are defined based on the page
table levels used by the host VA. So, the accessors may not work
if the guest uses more number of levels in stage2 than the stage1
of the host. In order to provide an independent stage2 page table,
we refactor the arm64 page table helpers to give us raw accessors
for each level, which should only used when that level is present.
And then, based on the VM, we make the decision of the stage2
page table using the raw accessors.
The series also adds :
- Support for handling 52bit IPA for vgic ITS.
- Cleanup in virtio to handle errors when the PFN used in
the virtio transport doesn't fit in 32bit.
Tested with
- Modified kvmtool, which can only be used for (patches included in
the series for reference / testing):
* with virtio-pci upto 44bit PA (Due to 4K page size for virtio-pci
legacy implemented by kvmtool)
* Upto 48bit PA with virtio-mmio, due to 32bit PFN limitation.
- Hacked Qemu (boot loader support for highmem, phys-shift support)
* with virtio-pci GIC-v3 ITS & MSI upto 52bit on Foundation model.
The series applies on arm64 for-next/core tree with 52bit PA support patches.
One would need the fix for virtio_mmio cleanup [1] on top of the arm64
tree to remove the warnings from virtio.
[1] https://marc.info/?l=linux-virtualization&m=151308636322117&w=2
Kristina Martsenko (1):
vgic: its: Add support for 52bit guest physical address
Suzuki K Poulose (15):
virtio: Validate queue pfn for 32bit transports
irqchip: gicv3-its: Add helpers for handling 52bit address
arm64: Make page table helpers reusable
arm64: Refactor pud_huge for reusability
arm64: Helper for parange to PASize
kvm: arm/arm64: Fix stage2_flush_memslot for 4 level page table
kvm: arm/arm64: Remove spurious WARN_ON
kvm: arm/arm64: Clean up stage2 pgd life time
kvm: arm/arm64: Delay stage2 page table allocation
kvm: arm/arm64: Prepare for VM specific stage2 translations
kvm: arm64: Make stage2 page table layout dynamic
kvm: arm64: Dynamic configuration of VTCR and VTTBR mask
kvm: arm64: Configure VTCR per VM
kvm: arm64: Switch to per VM IPA
kvm: arm64: Allow configuring physical address space size
Documentation/virtual/kvm/api.txt | 27 +++
arch/arm/include/asm/kvm_arm.h | 2 -
arch/arm/include/asm/kvm_host.h | 7 +
arch/arm/include/asm/kvm_mmu.h | 13 +-
arch/arm/include/asm/stage2_pgtable.h | 46 +++---
arch/arm64/include/asm/cpufeature.h | 16 ++
arch/arm64/include/asm/kvm_arm.h | 112 +++++++++++--
arch/arm64/include/asm/kvm_asm.h | 2 +-
arch/arm64/include/asm/kvm_host.h | 21 ++-
arch/arm64/include/asm/kvm_mmu.h | 83 ++++++++--
arch/arm64/include/asm/pgalloc.h | 32 +++-
arch/arm64/include/asm/pgtable.h | 61 ++++---
arch/arm64/include/asm/stage2_pgtable-nopmd.h | 42 -----
arch/arm64/include/asm/stage2_pgtable-nopud.h | 39 -----
arch/arm64/include/asm/stage2_pgtable.h | 211 ++++++++++++++++--------
arch/arm64/kvm/hyp/s2-setup.c | 34 +---
arch/arm64/kvm/hyp/switch.c | 8 +
arch/arm64/kvm/reset.c | 28 ++++
arch/arm64/mm/hugetlbpage.c | 2 +-
drivers/irqchip/irq-gic-v3-its.c | 2 +-
drivers/virtio/virtio_mmio.c | 19 ++-
drivers/virtio/virtio_pci_legacy.c | 11 +-
include/linux/irqchip/arm-gic-v3.h | 32 +++-
include/uapi/linux/kvm.h | 4 +
virt/kvm/arm/arm.c | 25 ++-
virt/kvm/arm/mmu.c | 228 +++++++++++++++-----------
virt/kvm/arm/vgic/vgic-its.c | 36 ++--
virt/kvm/arm/vgic/vgic-kvm-device.c | 2 +-
virt/kvm/arm/vgic/vgic-mmio-v3.c | 1 -
29 files changed, 738 insertions(+), 408 deletions(-)
delete mode 100644 arch/arm64/include/asm/stage2_pgtable-nopmd.h
delete mode 100644 arch/arm64/include/asm/stage2_pgtable-nopud.h
--
2.13.6
