MTE support for KVM guest

From:		Steven Price <steven.price-AT-arm.com>
To:		Catalin Marinas <catalin.marinas-AT-arm.com>, Marc Zyngier <maz-AT-kernel.org>, Will Deacon <will-AT-kernel.org>
Subject:		[PATCH v11 0/6] MTE support for KVM guest
Date:		Fri, 16 Apr 2021 16:43:03 +0100
Message-ID:		<20210416154309.22129-1-steven.price@arm.com>
Cc:		Steven Price <steven.price-AT-arm.com>, James Morse <james.morse-AT-arm.com>, Julien Thierry <julien.thierry.kdev-AT-gmail.com>, Suzuki K Poulose <suzuki.poulose-AT-arm.com>, kvmarm-AT-lists.cs.columbia.edu, linux-arm-kernel-AT-lists.infradead.org, linux-kernel-AT-vger.kernel.org, Dave Martin <Dave.Martin-AT-arm.com>, Mark Rutland <mark.rutland-AT-arm.com>, Thomas Gleixner <tglx-AT-linutronix.de>, qemu-devel-AT-nongnu.org, Juan Quintela <quintela-AT-redhat.com>, "Dr. David Alan Gilbert" <dgilbert-AT-redhat.com>, Richard Henderson <richard.henderson-AT-linaro.org>, Peter Maydell <peter.maydell-AT-linaro.org>, Haibo Xu <Haibo.Xu-AT-arm.com>, Andrew Jones <drjones-AT-redhat.com>
Archive-link:		Article

I know it's likely to be the merge window next week, but since there
were a couple of changes from Catalin's review I thought I'd send
another version out - there are some minor conflicts with what's
currently in -next so I'll rebase after -rc1.

This series adds support for using the Arm Memory Tagging Extensions
(MTE) in a KVM guest.

This version is rebased on v5.12-rc2.

Changes since v10[1]:

 * Replace pte_valid_user() with (pte_val(pte) & PTE_USER) in
   set_pte_at() as the former has been removed with the EPAN patches.
 * Don't attempt to check tags on memory which is going to be mapped in
   stage 2 as DEVICE as the guest won't be able to see the tags.
 * Use pfn_to_online_page() instead of pfn_to_page() in user_mem_abort()
   to prevent ZONE_DEVICE memory being populated in stage 2 if tags are
   enabled.

[1] https://lore.kernel.org/r/20210312151902.17853-1-steven.p...

Steven Price (6):
  arm64: mte: Sync tags for pages where PTE is untagged
  arm64: kvm: Introduce MTE VM feature
  arm64: kvm: Save/restore MTE registers
  arm64: kvm: Expose KVM_ARM_CAP_MTE
  KVM: arm64: ioctl to fetch/store tags in a guest
  KVM: arm64: Document MTE capability and ioctl

 Documentation/virt/kvm/api.rst             | 53 +++++++++++++++
 arch/arm64/include/asm/kvm_emulate.h       |  3 +
 arch/arm64/include/asm/kvm_host.h          |  9 +++
 arch/arm64/include/asm/kvm_mte.h           | 66 ++++++++++++++++++
 arch/arm64/include/asm/pgtable.h           |  2 +-
 arch/arm64/include/asm/sysreg.h            |  3 +-
 arch/arm64/include/uapi/asm/kvm.h          | 14 ++++
 arch/arm64/kernel/asm-offsets.c            |  3 +
 arch/arm64/kernel/mte.c                    | 16 +++--
 arch/arm64/kvm/arm.c                       | 78 ++++++++++++++++++++++
 arch/arm64/kvm/hyp/entry.S                 |  7 ++
 arch/arm64/kvm/hyp/exception.c             |  3 +-
 arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 21 ++++++
 arch/arm64/kvm/mmu.c                       | 20 ++++++
 arch/arm64/kvm/sys_regs.c                  | 28 ++++++--
 include/uapi/linux/kvm.h                   |  2 +
 16 files changed, 317 insertions(+), 11 deletions(-)
 create mode 100644 arch/arm64/include/asm/kvm_mte.h

-- 
2.20.1