[PATCH v4 00/38] KVM: arm64: Add support for protected guest memory with pKVM

Will Deacon
2026-03-27T14:00:51Z

Hi again, folks,

Here's v4 of the pKVM protected memory patches previously posted here:

v1: https://lore.kernel.org/kvmarm/20260105154939.11041-1-will@kernel.org/
v2: https://lore.kernel.org/kvmarm/20260119124629.2563-1-will@kernel.org/
v3: https://lore.kernel.org/r/20260305144351.17071-1-will@kernel.org

Changes since v3 include:

* Rebased onto v7.0-rc4
* Remove unused PKVM_ID_FFA
* Make ARM_PKVM_GUEST depend on DMA_RESTRICTED_POOL
* Use FAR_TO_FIPA_OFFSET() instead of open-coding it
* Remove PROTECTED_VM_UAPI config option and update documentation

As before, I've pushed an updated branch with this series:

https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/log/?h=kvm/protected-memory

and the kvmtool patches are available at:

https://git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/log/?h=pkvm

I fully expect to send a v5, as this is the first time Sashiko has had
a chance to chew on this and I'm expecting a roasting.

Cheers,

Will

Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oupton@kernel.org>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Quentin Perret <qperret@google.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Mostafa Saleh <smostafa@google.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>

--->8

Fuad Tabba (1):
KVM: arm64: Expose self-hosted debug regs as RAZ/WI for protected
guests

Quentin Perret (1):
KVM: arm64: Inject SIGSEGV on illegal accesses

Will Deacon (36):
KVM: arm64: Remove unused PKVM_ID_FFA definition
KVM: arm64: Don't leak stage-2 page-table if VM fails to init under
pKVM
KVM: arm64: Move handle check into pkvm_pgtable_stage2_destroy_range()
KVM: arm64: Rename __pkvm_pgtable_stage2_unmap()
KVM: arm64: Don't advertise unsupported features for protected guests
KVM: arm64: Remove is_protected_kvm_enabled() checks from hypercalls
KVM: arm64: Ignore MMU notifier callbacks for protected VMs
KVM: arm64: Prevent unsupported memslot operations on protected VMs
KVM: arm64: Ignore -EAGAIN when mapping in pages for the pKVM host
KVM: arm64: Split teardown hypercall into two phases
KVM: arm64: Introduce __pkvm_host_donate_guest()
KVM: arm64: Hook up donation hypercall to pkvm_pgtable_stage2_map()
KVM: arm64: Handle aborts from protected VMs
KVM: arm64: Introduce __pkvm_reclaim_dying_guest_page()
KVM: arm64: Hook up reclaim hypercall to pkvm_pgtable_stage2_destroy()
KVM: arm64: Factor out pKVM host exception injection logic
KVM: arm64: Support translation faults in inject_host_exception()
KVM: arm64: Avoid pointless annotation when mapping host-owned pages
KVM: arm64: Generalise kvm_pgtable_stage2_set_owner()
KVM: arm64: Introduce host_stage2_set_owner_metadata_locked()
KVM: arm64: Change 'pkvm_handle_t' to u16
KVM: arm64: Annotate guest donations with handle and gfn in host
stage-2
KVM: arm64: Introduce hypercall to force reclaim of a protected page
KVM: arm64: Reclaim faulting page from pKVM in spurious fault handler
KVM: arm64: Return -EFAULT from VCPU_RUN on access to a poisoned pte
KVM: arm64: Add hvc handler at EL2 for hypercalls from protected VMs
KVM: arm64: Implement the MEM_SHARE hypercall for protected VMs
KVM: arm64: Implement the MEM_UNSHARE hypercall for protected VMs
KVM: arm64: Allow userspace to create protected VMs when pKVM is
enabled
KVM: arm64: Add some initial documentation for pKVM
KVM: arm64: Extend pKVM page ownership selftests to cover guest
donation
KVM: arm64: Register 'selftest_vm' in the VM table
KVM: arm64: Extend pKVM page ownership selftests to cover forced
reclaim
KVM: arm64: Extend pKVM page ownership selftests to cover guest hvcs
KVM: arm64: Rename PKVM_PAGE_STATE_MASK
drivers/virt: pkvm: Add Kconfig dependency on DMA_RESTRICTED_POOL

.../admin-guide/kernel-parameters.txt | 4 +-
Documentation/virt/kvm/arm/index.rst | 1 +
Documentation/virt/kvm/arm/pkvm.rst | 106 ++++
arch/arm64/include/asm/kvm_asm.h | 31 +-
arch/arm64/include/asm/kvm_host.h | 9 +-
arch/arm64/include/asm/kvm_pgtable.h | 45 +-
arch/arm64/include/asm/kvm_pkvm.h | 4 +-
arch/arm64/include/asm/virt.h | 9 +
arch/arm64/kvm/arm.c | 12 +-
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 10 +-
arch/arm64/kvm/hyp/include/nvhe/memory.h | 12 +-
arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 7 +-
.../arm64/kvm/hyp/include/nvhe/trap_handler.h | 2 +
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 184 +++---
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 585 ++++++++++++++++--
arch/arm64/kvm/hyp/nvhe/pkvm.c | 224 ++++++-
arch/arm64/kvm/hyp/nvhe/switch.c | 1 +
arch/arm64/kvm/hyp/nvhe/sys_regs.c | 8 +
arch/arm64/kvm/hyp/pgtable.c | 33 +-
arch/arm64/kvm/mmu.c | 114 +++-
arch/arm64/kvm/pkvm.c | 151 ++++-
arch/arm64/mm/fault.c | 33 +-
drivers/virt/coco/pkvm-guest/Kconfig | 2 +-
include/uapi/linux/kvm.h | 5 +
24 files changed, 1365 insertions(+), 227 deletions(-)
create mode 100644 Documentation/virt/kvm/arm/pkvm.rst

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2.53.0.1018.g2bb0e51243-goog