[PATCH v2 00/18] KVM: arm64: Non-protected guest stage-2 support for pKVM

From: Quentin Perret
Date: Tue Dec 03 2024 - 05:37:55 EST


Hi all,

This is the v2 of the series adding support for non-protected guests to
pKVM. Please refer to v1 for all the context:

https://lore.kernel.org/kvmarm/20241104133204.85208-1-qperret@xxxxxxxxxx/

The series is organized as follows:

- Patches 01 to 04 move the host ownership state tracking from the
host's stage-2 page-table to the hypervisor's vmemmap. This avoids
fragmenting the host stage-2 for shared pages, which is only needed
to store an annotation in the SW bits of the corresponding PTE. All
pages mapped into non-protected guests are shared from pKVM's PoV,
so the cost of stage-2 fragmentation will increase massively as we
start tracking that at EL2. Note that these patches also help with
the existing sharing for e.g. FF-A, so they could possibly be merged
separately from the rest of the series.

- Patches 05 to 07 implement a minor refactoring of the pgtable code to
ease the integration of the pKVM MMU later on.

- Patches 08 to 16 introduce all the infrastructure needed on the pKVM
side for handling guest stage-2 page-tables at EL2.

- Patches 17 and 18 plumb the newly introduced pKVM support into
KVM/arm64.

Patches based on 6.13-rc1, tested on Pixel 6 and Qemu.

Changes in v2:
- Rebased on 6.13-rc1 (small conflicts with 2362506f7cff ("KVM: arm64:
Don't mark "struct page" accessed when making SPTE young") in
particular)
- Fixed kerneldoc breakage for __unmap_stage2_range()
- Fixed pkvm_pgtable_test_clear_young() to use correct HVC
- Folded guest_get_valid_pte() into __check_host_unshare_guest() for
clarity

Thanks,
Quentin

Marc Zyngier (1):
KVM: arm64: Introduce __pkvm_vcpu_{load,put}()

Quentin Perret (17):
KVM: arm64: Change the layout of enum pkvm_page_state
KVM: arm64: Move enum pkvm_page_state to memory.h
KVM: arm64: Make hyp_page::order a u8
KVM: arm64: Move host page ownership tracking to the hyp vmemmap
KVM: arm64: Pass walk flags to kvm_pgtable_stage2_mkyoung
KVM: arm64: Pass walk flags to kvm_pgtable_stage2_relax_perms
KVM: arm64: Make kvm_pgtable_stage2_init() a static inline function
KVM: arm64: Add {get,put}_pkvm_hyp_vm() helpers
KVM: arm64: Introduce __pkvm_host_share_guest()
KVM: arm64: Introduce __pkvm_host_unshare_guest()
KVM: arm64: Introduce __pkvm_host_relax_guest_perms()
KVM: arm64: Introduce __pkvm_host_wrprotect_guest()
KVM: arm64: Introduce __pkvm_host_test_clear_young_guest()
KVM: arm64: Introduce __pkvm_host_mkyoung_guest()
KVM: arm64: Introduce __pkvm_tlb_flush_vmid()
KVM: arm64: Introduce the EL1 pKVM MMU
KVM: arm64: Plumb the pKVM MMU in KVM

arch/arm64/include/asm/kvm_asm.h | 9 +
arch/arm64/include/asm/kvm_host.h | 4 +
arch/arm64/include/asm/kvm_pgtable.h | 42 ++-
arch/arm64/include/asm/kvm_pkvm.h | 28 ++
arch/arm64/kvm/arm.c | 23 +-
arch/arm64/kvm/hyp/include/nvhe/gfp.h | 6 +-
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 38 +--
arch/arm64/kvm/hyp/include/nvhe/memory.h | 43 ++-
arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 15 +
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 210 +++++++++++-
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 312 ++++++++++++++++--
arch/arm64/kvm/hyp/nvhe/page_alloc.c | 14 +-
arch/arm64/kvm/hyp/nvhe/pkvm.c | 56 ++++
arch/arm64/kvm/hyp/nvhe/setup.c | 7 +-
arch/arm64/kvm/hyp/pgtable.c | 13 +-
arch/arm64/kvm/mmu.c | 109 ++++--
arch/arm64/kvm/pkvm.c | 195 +++++++++++
arch/arm64/kvm/vgic/vgic-v3.c | 6 +-
18 files changed, 987 insertions(+), 143 deletions(-)

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2.47.0.338.g60cca15819-goog