[PATCH v8 0/2] arm64 tagged address ABI

From: Catalin Marinas <catalin.marinas@arm.com>
To: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	Andrey Konovalov <andreyknvl@google.com>,
	Szabolcs Nagy <szabolcs.nagy@arm.com>,
	Kevin Brodsky <kevin.brodsky@arm.com>,
	Dave P Martin <Dave.Martin@arm.com>,
	Dave Hansen <dave.hansen@intel.com>,
	linux-doc@vger.kernel.org, linux-arch@vger.kernel.org
Subject: [PATCH v8 0/2] arm64 tagged address ABI
Date: Thu, 15 Aug 2019 16:43:58 +0100	[thread overview]
Message-ID: <20190815154403.16473-1-catalin.marinas@arm.com> (raw)

Hi,

This series contains an update to the arm64 tagged address ABI
documentation posted here (v7):

http://lkml.kernel.org/r/20190807155321.9648-1-catalin.marinas@arm.com

together some adjustments to Andrey's patches (already queued through
different trees) following the discussions on the ABI documents:

http://lkml.kernel.org/r/cover.1563904656.git.andreyknvl@google.com

If there are not objections, I propose that that patch 1 (mm: untag user
pointers in mmap...) goes via the mm tree while the other 4 are routed
via the arm64 tree.

Changes in v8:

- removed mmap/munmap/mremap/brk from the list of syscalls not accepting
  tagged pointers

- added ioctl() to the list of syscalls not accepting tagged pointers

- added shmat/shmdt to a list of syscalls not accepting tagged pointers

- prctl() now requires all unused arguments to be 0

- note about two-stage ABI relaxation since even without the prctl()
  opt-in, the tag is still ignored on a few syscalls (untagged_addr() in
  the kernel is unconditional)

- compilable example code together with syscall use

- added a note on tag preservation in the tagged-pointers.rst document

- various rewordings and cleanups

Catalin Marinas (3):
  mm: untag user pointers in mmap/munmap/mremap/brk
  arm64: Tighten the PR_{SET,GET}_TAGGED_ADDR_CTRL prctl() unused
    arguments
  arm64: Change the tagged_addr sysctl control semantics to only prevent
    the opt-in

Vincenzo Frascino (2):
  arm64: Define Documentation/arm64/tagged-address-abi.rst
  arm64: Relax Documentation/arm64/tagged-pointers.rst

 Documentation/arm64/tagged-address-abi.rst | 155 +++++++++++++++++++++
 Documentation/arm64/tagged-pointers.rst    |  23 ++-
 arch/arm64/kernel/process.c                |  17 ++-
 kernel/sys.c                               |   4 +
 mm/mmap.c                                  |   5 +
 mm/mremap.c                                |   6 +-
 6 files changed, 191 insertions(+), 19 deletions(-)
 create mode 100644 Documentation/arm64/tagged-address-abi.rst