[PATCH v5 00/25] arm64: Memory Tagging Extension user-space support

Catalin Marinas
2020-06-24T17:52:49Z

This is the 5th version (4th version here [1]) of the series adding
user-space support for the ARMv8.5 Memory Tagging Extension ([2], [3]).
The patches are also available on this branch:

git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux devel/mte-v5

There are no user ABI changes from v4 and I do not anticipate further
updates affecting the ABI. Subsequent ABI improvements, if needed, will
be done in a backwards-compatible manner. The glibc counterpart is also
under discussion [4].

My plan is to push these patches into linux-next for wider coverage,
with an aim for merging into 5.9 unless major reworking is needed. I
would be grateful if mm folks review/ack/nak those patches touching mm/
(and, of course, any other patch in this series, feedback always
welcomed). Thank you.

Changes in this version:

- Removed the Device Tree memory node description requirement after
agreement with the hardware architects that the CPUID should reflect
the features supported by the general purpose memory.

- Dropped the command line argument to disable MTE at boot in the
absence of a strong argument in its favour.

- Fixed handling of compound pages (inadvertently clearing valid tags in
previously mapped small pages).

- Some reworking of the copy_{user,}highpage() functions.

- Rebased to 5.8-rc2

[1] https://lore.kernel.org/linux-arm-kernel/20200515171612.1020-1-catalin.marinas@arm.com/
[2] https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/enhancing-memory-safety
[3] https://developer.arm.com/-/media/Arm%20Developer%20Community/PDF/Arm_Memory_Tagging_Extension_Whitepaper.pdf
[4] https://sourceware.org/pipermail/libc-alpha/2020-June/115039.html

Catalin Marinas (13):
arm64: mte: Use Normal Tagged attributes for the linear map
arm64: mte: Clear the tags when a page is mapped in user-space with
PROT_MTE
arm64: Avoid unnecessary clear_user_page() indirection
arm64: mte: Tags-aware aware memcmp_pages() implementation
arm64: mte: Add PROT_MTE support to mmap() and mprotect()
mm: Introduce arch_validate_flags()
arm64: mte: Validate the PROT_MTE request via arch_validate_flags()
mm: Allow arm64 mmap(PROT_MTE) on RAM-based files
arm64: mte: Allow user control of the tag check mode via prctl()
arm64: mte: Allow user control of the generated random tags via
prctl()
arm64: mte: Restore the GCR_EL1 register after a suspend
arm64: mte: Add PTRACE_{PEEK,POKE}MTETAGS support
fs: Handle intra-page faults in copy_mount_options()

Kevin Brodsky (1):
mm: Introduce arch_calc_vm_flag_bits()

Steven Price (4):
mm: Add PG_ARCH_2 page flag
mm: Add arch hooks for saving/restoring tags
arm64: mte: Enable swap of tagged pages
arm64: mte: Save tags when hibernating

Vincenzo Frascino (7):
arm64: mte: system register definitions
arm64: mte: CPU feature detection and initial sysreg configuration
arm64: mte: Add specific SIGSEGV codes
arm64: mte: Handle synchronous and asynchronous tag check faults
arm64: mte: Tags-aware copy_{user_,}highpage() implementations
arm64: mte: Kconfig entry
arm64: mte: Add Memory Tagging Extension documentation

Documentation/arm64/cpu-feature-registers.rst | 2 +
Documentation/arm64/elf_hwcaps.rst | 4 +
Documentation/arm64/index.rst | 1 +
.../arm64/memory-tagging-extension.rst | 297 ++++++++++++++++
arch/arm64/Kconfig | 29 ++
arch/arm64/include/asm/cpucaps.h | 3 +-
arch/arm64/include/asm/cpufeature.h | 6 +
arch/arm64/include/asm/hwcap.h | 1 +
arch/arm64/include/asm/kvm_arm.h | 3 +-
arch/arm64/include/asm/memory.h | 17 +-
arch/arm64/include/asm/mman.h | 56 ++-
arch/arm64/include/asm/mte.h | 86 +++++
arch/arm64/include/asm/page.h | 19 +-
arch/arm64/include/asm/pgtable-prot.h | 2 +
arch/arm64/include/asm/pgtable.h | 46 ++-
arch/arm64/include/asm/processor.h | 4 +
arch/arm64/include/asm/sysreg.h | 61 ++++
arch/arm64/include/asm/thread_info.h | 4 +-
arch/arm64/include/uapi/asm/hwcap.h | 1 +
arch/arm64/include/uapi/asm/mman.h | 1 +
arch/arm64/include/uapi/asm/ptrace.h | 4 +
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/cpufeature.c | 61 ++++
arch/arm64/kernel/cpuinfo.c | 1 +
arch/arm64/kernel/entry.S | 37 ++
arch/arm64/kernel/hibernate.c | 118 +++++++
arch/arm64/kernel/mte.c | 331 ++++++++++++++++++
arch/arm64/kernel/process.c | 31 +-
arch/arm64/kernel/ptrace.c | 9 +-
arch/arm64/kernel/signal.c | 8 +
arch/arm64/kernel/suspend.c | 4 +
arch/arm64/kernel/syscall.c | 10 +
arch/arm64/lib/Makefile | 2 +
arch/arm64/lib/mte.S | 151 ++++++++
arch/arm64/mm/Makefile | 1 +
arch/arm64/mm/copypage.c | 25 +-
arch/arm64/mm/dump.c | 4 +
arch/arm64/mm/fault.c | 9 +-
arch/arm64/mm/mmu.c | 22 +-
arch/arm64/mm/mteswap.c | 82 +++++
arch/arm64/mm/proc.S | 8 +-
arch/x86/kernel/signal_compat.c | 2 +-
fs/namespace.c | 24 +-
fs/proc/page.c | 3 +
fs/proc/task_mmu.c | 4 +
include/{linux => asm-generic}/pgtable.h | 222 ++----------
include/linux/kernel-page-flags.h | 1 +
include/linux/mm.h | 8 +
include/linux/mman.h | 22 +-
include/linux/page-flags.h | 3 +
include/linux/pgtable.h | 23 ++
include/trace/events/mmflags.h | 9 +-
include/uapi/asm-generic/siginfo.h | 4 +-
include/uapi/linux/prctl.h | 9 +
mm/Kconfig | 3 +
mm/mmap.c | 9 +
mm/mprotect.c | 6 +
mm/page_io.c | 10 +
mm/shmem.c | 9 +
mm/swapfile.c | 2 +
mm/util.c | 2 +-
tools/vm/page-types.c | 2 +
62 files changed, 1704 insertions(+), 235 deletions(-)
create mode 100644 Documentation/arm64/memory-tagging-extension.rst
create mode 100644 arch/arm64/include/asm/mte.h
create mode 100644 arch/arm64/kernel/mte.c
create mode 100644 arch/arm64/lib/mte.S
create mode 100644 arch/arm64/mm/mteswap.c
copy include/{linux => asm-generic}/pgtable.h (85%)