mbox series

[v4,00/21] Track shared pages at EL2 in protected mode

Message ID 20210809152448.1810400-1-qperret@google.com (mailing list archive)
Headers show
Series Track shared pages at EL2 in protected mode | expand

Message

Quentin Perret Aug. 9, 2021, 3:24 p.m. UTC
Hi all,

This is v4 of the patch series previously posted here:

https://lore.kernel.org/lkml/20210729132818.4091769-1-qperret@google.com/

This series aims to improve how the nVHE hypervisor tracks ownership of
memory pages when running in protected mode ("kvm-arm.mode=protected" on
the kernel command line).

The main issue with the existing ownership tracking code is that it is
completely binary: a page is either owned by an entity (e.g. the host)
or not. However, we'll need something smarter to track shared pages, as
is needed for virtio, or even just host/hypervisor communications.

This series introduces a few changes to the kvm page-table library to
allow annotating shared pages in ignored bits (a.k.a. software bits) of
leaf entries, and makes use of that infrastructure to track all pages
that are shared between the host and the hypervisor. We will obviously
want to apply the same treatment to guest stage-2 page-tables, but that
is not really possible to do until EL2 manages them directly, so I'll
keep that for another series.

The series is based on the 5.14-rc5, and has been tested on
AML-S905X-CC (Le Potato) and using various Qemu configurations.

Changes since v3
 - Fixed typos in comments / commit messages;
 - Various small cleanups and refactoring;
 - Rebased on 5.14-rc5.

Marc Zyngier (1):
  KVM: arm64: Introduce helper to retrieve a PTE and its level

Quentin Perret (19):
  KVM: arm64: Introduce hyp_assert_lock_held()
  KVM: arm64: Provide the host_stage2_try() helper macro
  KVM: arm64: Expose page-table helpers
  KVM: arm64: Optimize host memory aborts
  KVM: arm64: Rename KVM_PTE_LEAF_ATTR_S2_IGNORED
  KVM: arm64: Don't overwrite software bits with owner id
  KVM: arm64: Tolerate re-creating hyp mappings to set software bits
  KVM: arm64: Enable forcing page-level stage-2 mappings
  KVM: arm64: Allow populating software bits
  KVM: arm64: Add helpers to tag shared pages in SW bits
  KVM: arm64: Expose host stage-2 manipulation helpers
  KVM: arm64: Expose pkvm_hyp_id
  KVM: arm64: Introduce addr_is_memory()
  KVM: arm64: Enable retrieving protections attributes of PTEs
  KVM: arm64: Mark host bss and rodata section as shared
  KVM: arm64: Remove __pkvm_mark_hyp
  KVM: arm64: Refactor protected nVHE stage-1 locking
  KVM: arm64: Restrict EL2 stage-1 changes in protected mode
  KVM: arm64: Make __pkvm_create_mappings static

Will Deacon (1):
  KVM: arm64: Add hyp_spin_is_locked() for basic locking assertions at
    EL2

 arch/arm64/include/asm/kvm_asm.h              |   5 +-
 arch/arm64/include/asm/kvm_pgtable.h          | 167 ++++++++----
 arch/arm64/kvm/Kconfig                        |   9 +
 arch/arm64/kvm/arm.c                          |  46 ----
 arch/arm64/kvm/hyp/include/nvhe/mem_protect.h |  33 ++-
 arch/arm64/kvm/hyp/include/nvhe/mm.h          |   3 +-
 arch/arm64/kvm/hyp/include/nvhe/spinlock.h    |  25 ++
 arch/arm64/kvm/hyp/nvhe/hyp-main.c            |  20 +-
 arch/arm64/kvm/hyp/nvhe/mem_protect.c         | 225 +++++++++++++---
 arch/arm64/kvm/hyp/nvhe/mm.c                  |  22 +-
 arch/arm64/kvm/hyp/nvhe/setup.c               |  82 +++++-
 arch/arm64/kvm/hyp/pgtable.c                  | 247 +++++++++---------
 arch/arm64/kvm/mmu.c                          |  28 +-
 13 files changed, 628 insertions(+), 284 deletions(-)

Comments

Marc Zyngier Aug. 11, 2021, 11:25 a.m. UTC | #1
On Mon, 9 Aug 2021 16:24:27 +0100, Quentin Perret wrote:
> This is v4 of the patch series previously posted here:
> 
> https://lore.kernel.org/lkml/20210729132818.4091769-1-qperret@google.com/
> 
> This series aims to improve how the nVHE hypervisor tracks ownership of
> memory pages when running in protected mode ("kvm-arm.mode=protected" on
> the kernel command line).
> 
> [...]

Applied to next, thanks!

[01/21] KVM: arm64: Add hyp_spin_is_locked() for basic locking assertions at EL2
        commit: d21292f13f1f0721d60e8122e2db46bea8cf6950
[02/21] KVM: arm64: Introduce hyp_assert_lock_held()
        commit: 8e049e0daf23aa380c264e5e15e4c64ea5497ed7
[03/21] KVM: arm64: Provide the host_stage2_try() helper macro
        commit: 1bac49d490cbc813f407a5c9806e464bf4a300c9
[05/21] KVM: arm64: Expose page-table helpers
        commit: 51add457733bbc4a442fc280d73d14bfe262e4a0
[06/21] KVM: arm64: Optimize host memory aborts
        commit: c4f0935e4d957bfcea25ad76860445660a60f3fd
[07/21] KVM: arm64: Rename KVM_PTE_LEAF_ATTR_S2_IGNORED
        commit: 178cac08d588e7406a09351a992f57892d8d9cc9
[08/21] KVM: arm64: Don't overwrite software bits with owner id
        commit: 8a0282c68121e53ab17413283cfed408a47e1a2a
[09/21] KVM: arm64: Tolerate re-creating hyp mappings to set software bits
        commit: b53846c5f279cb5329b82f19a7d313f02cb9d21c
[10/21] KVM: arm64: Enable forcing page-level stage-2 mappings
        commit: 5651311941105ca077d3ab74dd4a92e646ecf7fb
[11/21] KVM: arm64: Allow populating software bits
        commit: 4505e9b624cefafa4b75d8a28e72f32076c33375
[12/21] KVM: arm64: Add helpers to tag shared pages in SW bits
        commit: ec250a67ea8db6209918a389554cf3aec0395b1f
[13/21] KVM: arm64: Expose host stage-2 manipulation helpers
        commit: 39257da0e04e5cdb1e4a3ca715dc3d949fe8b059
[14/21] KVM: arm64: Expose pkvm_hyp_id
        commit: 2d77e238badb022adb364332b7d6a1d627f77145
[15/21] KVM: arm64: Introduce addr_is_memory()
        commit: e009dce1292c37cf8ee7c33e0887ad3c642f980f
[16/21] KVM: arm64: Enable retrieving protections attributes of PTEs
        commit: 9024b3d0069ab4b8ef70cf55f0ee09e61f3a0747
[17/21] KVM: arm64: Mark host bss and rodata section as shared
        commit: 2c50166c62ba7f3c23c1bbdbb9324db462ddc97b
[18/21] KVM: arm64: Remove __pkvm_mark_hyp
        commit: ad0e0139a8e163245d8f44ab4f6ec3bc9b08034d
[19/21] KVM: arm64: Refactor protected nVHE stage-1 locking
        commit: f9370010e92638f66473baf342e19de940403362
[20/21] KVM: arm64: Restrict EL2 stage-1 changes in protected mode
        commit: 66c57edd3bc79e3527daaae8123f72ecd1e3fa25
[21/21] KVM: arm64: Make __pkvm_create_mappings static
        commit: 64a80fb766f9a91e26930bfc56d8e7c12425df12

Note that patch #4 has been used as the base for this series,
and is already part of the mapping level rework.

Cheers,

	M.