[v2,0/4] arm64: add Armv8.6 pointer authentication

Message

Amit Daniel Kachhap April 14, 2020, 5:31 a.m. UTC

Hi all,

These patch series adds support for Armv8.6 pointer authentication
enhanced mandatory features. These features are,

 * Enhanced PAC generation algorithm.
 * Generate fault when authenticate instruction fails.

For the first feature no code change is done and for the second feature
a ptrauth fault handler is added.
More details can be found here [1].

Changes since v1:
* Patch 1 is newly added and fixes a meta cpucapability check.
* Patch 3 is forked out from earlier patch 1 ("arm64: ptrauth: add pointer
  authentication Armv8.6 enhanced feature"). This was suggested by Will
  [2].

This series is based on kernel version v5.7-rc1.

Note: patch 4 may need some changes with Mark Brown's work on whitelisting
of hint instructions [3].

Regards,
Amit

[1]: https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a
[2]: http://lists.infradead.org/pipermail/linux-arm-kernel/2020-March/715443.html
[3]: http://lists.infradead.org/pipermail/linux-arm-kernel/2020-March/720280.html

Amit Daniel Kachhap (4):
  arm64: cpufeature: Extract meta-capability scope from list
  arm64: ptrauth: add pointer authentication Armv8.6 enhanced feature
  arm64: cpufeature: Modify address authentication cpufeature to exact
  arm64: kprobe: disable probe of fault prone ptrauth instruction

 arch/arm64/include/asm/esr.h           |  4 +++-
 arch/arm64/include/asm/exception.h     |  1 +
 arch/arm64/include/asm/insn.h          | 13 +++++++------
 arch/arm64/include/asm/sysreg.h        | 24 ++++++++++++++++--------
 arch/arm64/kernel/cpufeature.c         | 22 +++++++++++-----------
 arch/arm64/kernel/entry-common.c       | 25 +++++++++++++++++++++++++
 arch/arm64/kernel/insn.c               |  1 +
 arch/arm64/kernel/probes/decode-insn.c |  2 +-
 arch/arm64/kernel/traps.c              | 18 ++++++++++++++++++
 9 files changed, 83 insertions(+), 27 deletions(-)