[PATCH v2 0/3] Support Common Not Private translations

Vladimir Murzin
2017-10-11T12:19:31Z

Common Not Private (CNP) translations is a feature of ARMv8.2
extension which allows translation table entries to be shared between
different PEs in the same inner shareable domain, so the hardware can
use this fact to optimise the caching of such entries in the TLB.

This patch set is an attempt to bring CNP support into Linux. It was
tested on a v8.2 Fast Model with exploring traces and checking that
TTBRx_ELy and VTTBR_EL2 have CnP bit set where appropriate.

Changelog:
v1 -> v2
- handle cpuilde case (per James)
- use lm_allias with swapper_pg_dir (per James)
- rule out ARM64_SW_TTBR0_PAN case (per Catalin)
- s/BUG_ON/WARN_ON/ (per Catalin)
- comment and commit message updates (per Catalin)
- TTBR_CNP_BIT moved to asm/pgtable-hwdef.h (per Catalin)
- has_useable_cnp() simplified (per Julien)

RFC -> v1
- dropped RFC tag
- rebased on 4.14-rc4

Thanks!

Vladimir Murzin (3):
arm64: mm: Support Common Not Private translations
arm64: KVM: Support Common Not Private translations
arm64: Introduce command line parameter to disable CNP

Documentation/admin-guide/kernel-parameters.txt | 4 +++
arch/arm64/Kconfig | 14 +++++++++++
arch/arm64/include/asm/cpucaps.h | 3 ++-
arch/arm64/include/asm/cpufeature.h | 6 +++++
arch/arm64/include/asm/mmu_context.h | 12 +++++++++
arch/arm64/include/asm/pgtable-hwdef.h | 2 ++
arch/arm64/kernel/cpufeature.c | 33 +++++++++++++++++++++++++
arch/arm64/kernel/hibernate.c | 2 +-
arch/arm64/kernel/suspend.c | 3 +++
arch/arm64/kvm/hyp-init.S | 4 +++
arch/arm64/kvm/hyp/switch.c | 6 ++++-
arch/arm64/mm/proc.S | 5 ++++
12 files changed, 91 insertions(+), 3 deletions(-)

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2.0.0