[PATCH 0/9] 52-bit kernel + user VAs

From: Steve Capper <steve.capper@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: crecklin@redhat.com, Steve Capper <steve.capper@arm.com>,
	marc.zyngier@arm.com, catalin.marinas@arm.com,
	ard.biesheuvel@linaro.org, will.deacon@arm.com
Subject: [PATCH 0/9] 52-bit kernel + user VAs
Date: Mon, 18 Feb 2019 17:02:36 +0000	[thread overview]
Message-ID: <20190218170245.14915-1-steve.capper@arm.com> (raw)

This patch series adds support for 52-bit kernel VAs using some of the
machinery already introduced by the 52-bit userspace VA code in 5.0.

As 52-bit virtual address support is an optional hardware feature,
software support for 52-bit kernel VAs needs to be deduced at early boot
time. If HW support is not available, the kernel falls back to 48-bit.

A significant proportion of this series focuses on "de-constifying"
VA_BITS related constants.

In order to allow for a KASAN shadow that changes size at boot time, one
must fix the KASAN_SHADOW_END for both 48 & 52-bit VAs and "grow" the
start address. Also, it is highly desirable to maintain the same
function addresses in the kernel .text between VA sizes. Both of these
requirements necessitate us to flip the kernel address space halves s.t.
the direct linear map occupies the lower addresses.

One obvious omission is 52-bit kernel VA + 48-bit userspace VA which I
can add with some more #ifdef'ery if needed.

Cheers,
-- 
Steve

Steve Capper (9):
  arm/arm64: KVM: Formalise end of direct linear map
  arm64: mm: Flip kernel VA space
  arm64: kasan: Switch to using KASAN_SHADOW_OFFSET
  arm64: mm: Replace fixed map BUILD_BUG_ON's with BUG_ON's
  arm64: dump: Make kernel page table dumper dynamic again
  arm64: mm: Introduce VA_BITS_MIN
  arm64: mm: Introduce VA_BITS_ACTUAL
  arm64: mm: Logic to make offset_ttbr1 conditional
  arm64: mm: Introduce 52-bit Kernel VAs

 Documentation/arm64/kasan-offsets.sh   | 27 ++++++++++++
 arch/arm/include/asm/memory.h          |  1 +
 arch/arm64/Kconfig                     | 46 +++++++++++++++++++-
 arch/arm64/Makefile                    |  8 ----
 arch/arm64/include/asm/assembler.h     | 17 +++++++-
 arch/arm64/include/asm/cpucaps.h       |  3 +-
 arch/arm64/include/asm/efi.h           |  4 +-
 arch/arm64/include/asm/kasan.h         | 11 ++---
 arch/arm64/include/asm/memory.h        | 33 +++++++++------
 arch/arm64/include/asm/mmu_context.h   |  4 +-
 arch/arm64/include/asm/pgtable-hwdef.h |  2 +-
 arch/arm64/include/asm/pgtable.h       |  2 +-
 arch/arm64/include/asm/processor.h     |  2 +-
 arch/arm64/kernel/cpufeature.c         | 18 ++++++++
 arch/arm64/kernel/head.S               | 25 +++++++++--
 arch/arm64/kernel/hibernate-asm.S      |  1 +
 arch/arm64/kernel/kaslr.c              |  6 +--
 arch/arm64/kvm/va_layout.c             | 14 +++----
 arch/arm64/mm/dump.c                   | 58 +++++++++++++++++++++-----
 arch/arm64/mm/fault.c                  |  4 +-
 arch/arm64/mm/init.c                   | 14 +++----
 arch/arm64/mm/kasan_init.c             | 11 +++--
 arch/arm64/mm/mmu.c                    | 13 +++---
 arch/arm64/mm/proc.S                   |  6 ++-
 virt/kvm/arm/mmu.c                     |  4 +-
 25 files changed, 247 insertions(+), 87 deletions(-)
 create mode 100644 Documentation/arm64/kasan-offsets.sh

-- 
2.20.1

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