[PATCH v4 00/25] KVM: arm64: Introduce pKVM hyp VM and vCPU state at EL2

Will Deacon
2022-10-17T11:53:41Z

Hi everyone,

This is version four of the patches previously posted at:

Mega-patch: https://lore.kernel.org/kvmarm/20220519134204.5379-1-will@kernel.org/
v2: https://lore.kernel.org/all/20220630135747.26983-1-will@kernel.org/
v3: https://lore.kernel.org/kvmarm/20220914083500.5118-1-will@kernel.org/

This series extends the pKVM EL2 code so that it can dynamically
instantiate and manage VM data structures without the host being able to
access them directly. These structures consist of a hyp VM, a set of hyp
vCPUs and the stage-2 page-table for the MMU. The pages used to hold the
hypervisor structures are returned to the host when the VM is destroyed.

There are only a few small changes for v4:

* Fixed missing cache maintenance when reclaiming guest pages on a system
with the FWB ("Force WriteBack") CPU feature
* Added a comment about locking requirements for refcount manipulation
* Fixed a kbuild robot complaint when using 52-bit physical addresses
* Added Vincent's Tested-by for the series
* Added Oliver's Reviewed-by for the first patch
* Rebased onto 6.1-rc1

One big change since v3 is that Quentin's pKVM "technical deep dive" talk
from this year's KVM forum is now online and hopefully provides an
enjoyable narrative to this series:

https://www.youtube.com/watch?v=9npebeVFbFw

There are still a bunch of extra patches needed to achieve guest/host
isolation, but that follow-up work is largely stalled pending resolution
of the guest private memory API (although KVM forum provided an
excellent venue to iron some of those details out!):

https://lore.kernel.org/kvm/20220915142913.2213336-1-chao.p.peng@linux.intel.com/T/#t

The last patch remains "RFC" as it's primarily intended for testing and
I couldn't think of a better way to flag it.

Cheers,

Will, Quentin, Fuad and Marc

Cc: Sean Christopherson <seanjc@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Chao Peng <chao.p.peng@linux.intel.com>
Cc: Quentin Perret <qperret@google.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Marc Zyngier <maz@kernel.org>

Cc: kernel-team@android.com
Cc: kvm@vger.kernel.org
Cc: kvmarm@lists.linux.dev
Cc: linux-arm-kernel@lists.infradead.org

--->8

Fuad Tabba (3):
KVM: arm64: Add hyp_spinlock_t static initializer
KVM: arm64: Add infrastructure to create and track pKVM instances at
EL2
KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from
EL1

Quentin Perret (15):
KVM: arm64: Move hyp refcount manipulation helpers to common header
file
KVM: arm64: Allow attaching of non-coalescable pages to a hyp pool
KVM: arm64: Back the hypervisor 'struct hyp_page' array for all memory
KVM: arm64: Fix-up hyp stage-1 refcounts for all pages mapped at EL2
KVM: arm64: Implement do_donate() helper for donating memory
KVM: arm64: Prevent the donation of no-map pages
KVM: arm64: Add helpers to pin memory shared with the hypervisor at
EL2
KVM: arm64: Add per-cpu fixmap infrastructure at EL2
KVM: arm64: Add generic hyp_memcache helpers
KVM: arm64: Consolidate stage-2 initialisation into a single function
KVM: arm64: Instantiate guest stage-2 page-tables at EL2
KVM: arm64: Return guest memory from EL2 via dedicated teardown
memcache
KVM: arm64: Unmap 'kvm_arm_hyp_percpu_base' from the host
KVM: arm64: Explicitly map 'kvm_vgic_global_state' at EL2
KVM: arm64: Don't unnecessarily map host kernel sections at EL2

Will Deacon (7):
KVM: arm64: Unify identifiers used to distinguish host and hypervisor
KVM: arm64: Include asm/kvm_mmu.h in nvhe/mem_protect.h
KVM: arm64: Rename 'host_kvm' to 'host_mmu'
KVM: arm64: Initialise hypervisor copies of host symbols
unconditionally
KVM: arm64: Provide I-cache invalidation by virtual address at EL2
KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2
KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run()

arch/arm64/include/asm/kvm_arm.h | 2 +-
arch/arm64/include/asm/kvm_asm.h | 7 +-
arch/arm64/include/asm/kvm_host.h | 73 ++-
arch/arm64/include/asm/kvm_hyp.h | 3 +
arch/arm64/include/asm/kvm_mmu.h | 2 +-
arch/arm64/include/asm/kvm_pgtable.h | 22 +
arch/arm64/include/asm/kvm_pkvm.h | 38 ++
arch/arm64/kernel/image-vars.h | 15 -
arch/arm64/kvm/arm.c | 61 ++-
arch/arm64/kvm/hyp/hyp-constants.c | 3 +
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 25 +-
arch/arm64/kvm/hyp/include/nvhe/memory.h | 27 +
arch/arm64/kvm/hyp/include/nvhe/mm.h | 18 +-
arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 74 +++
arch/arm64/kvm/hyp/include/nvhe/spinlock.h | 10 +-
arch/arm64/kvm/hyp/nvhe/cache.S | 11 +
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 110 +++-
arch/arm64/kvm/hyp/nvhe/hyp-smp.c | 2 +
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 502 ++++++++++++++++--
arch/arm64/kvm/hyp/nvhe/mm.c | 158 +++++-
arch/arm64/kvm/hyp/nvhe/page_alloc.c | 28 +-
arch/arm64/kvm/hyp/nvhe/pkvm.c | 444 ++++++++++++++++
arch/arm64/kvm/hyp/nvhe/setup.c | 96 ++--
arch/arm64/kvm/hyp/pgtable.c | 21 +-
arch/arm64/kvm/mmu.c | 55 +-
arch/arm64/kvm/pkvm.c | 138 ++++-
arch/arm64/kvm/reset.c | 29 -
27 files changed, 1758 insertions(+), 216 deletions(-)
create mode 100644 arch/arm64/kvm/hyp/include/nvhe/pkvm.h

--
2.38.0.413.g74048e4d9e-goog