[PATCH v2 0/7] Move pKVM ownership state to hyp_vmemmap

Quentin Perret qperret at google.com
Wed Apr 16 08:26:40 PDT 2025


Hi all,

This series moves the hypervisor's ownership state to the hyp_vmemmap,
as discussed in [1]. The two main benefits are:

 1. much cheaper hyp state lookups, since we can avoid the hyp stage-1
    page-table walk;

 2. de-correlates the hyp state from the presence of a mapping in the
    linear map range of the hypervisor; which enables a bunch of
    clean-ups in the existing code and will simplify the introduction of
    other features in the future (hyp tracing, ...)

Patch 01 is a self-sufficient cleanup that I found thanks to patch 06.
Patch 02 is another self-sufficient cleanup that came out from the
discussion with Marc at [2]. Patches 03-05 implement the aforementioned
migration of the hyp state to the vmemmap. Patches 06 and 07 are further
improvements enabled by that migration.

Changes since v1:
 - fixed page-tracking comments in nvhe/memory.h
 - rebased on 6.15-rc2
 - applied Marc's Reviewed-by

Thanks,
Quentin

[1] https://lore.kernel.org/kvmarm/Z79ZJVOHtNu6YsVt@google.com/
[2] https://lore.kernel.org/kvmarm/867c4pnspi.wl-maz@kernel.org/

Fuad Tabba (1):
  KVM: arm64: Track SVE state in the hypervisor vcpu structure

Quentin Perret (6):
  KVM: arm64: Fix pKVM page-tracking comments
  KVM: arm64: Use 0b11 for encoding PKVM_NOPAGE
  KVM: arm64: Introduce {get,set}_host_state() helpers
  KVM: arm64: Move hyp state to hyp_vmemmap
  KVM: arm64: Defer EL2 stage-1 mapping on share
  KVM: arm64: Unconditionally cross check hyp state

 arch/arm64/include/asm/kvm_host.h        |  12 +--
 arch/arm64/kvm/hyp/include/nvhe/memory.h |  58 ++++++++++---
 arch/arm64/kvm/hyp/nvhe/hyp-main.c       |   4 -
 arch/arm64/kvm/hyp/nvhe/mem_protect.c    | 106 ++++++++++++-----------
 arch/arm64/kvm/hyp/nvhe/pkvm.c           |  47 +++++++++-
 arch/arm64/kvm/hyp/nvhe/setup.c          |  10 ++-
 6 files changed, 158 insertions(+), 79 deletions(-)

-- 
2.49.0.604.gff1f9ca942-goog




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