[v2,0/3] Change default pointer authentication algorithm on aarch64 to impdef

Message

Pierrick Bouvier Dec. 19, 2024, 6:32 p.m. UTC

qemu-system-aarch64 default pointer authentication (QARMA5) is expensive, we
spent up to 50% of the emulation time running it (when using TCG).

Switching to pauth-impdef=on is often given as a solution to speed up execution.
Thus we talked about making it the new default.

The first patch introduce a new property (pauth-qarma5) to allow to select
current default algorithm.
The second one change the default.
The third one updates documentation.

v2:
- ensure we don't break migration compatibility, by using a specific backward
  compatible property.
- added some documentation about migration for arm virt machine model.

Pierrick Bouvier (3):
  target/arm: add new property to select pauth-qarma5
  target/arm: change default pauth algorithm to impdef
  docs/system/arm/virt: mention specific migration information

 docs/system/arm/cpu-features.rst |  7 ++++--
 docs/system/arm/virt.rst         | 14 +++++++++---
 docs/system/introduction.rst     |  2 +-
 target/arm/cpu.h                 |  4 ++++
 hw/core/machine.c                |  4 +++-
 target/arm/arm-qmp-cmds.c        |  2 +-
 target/arm/cpu.c                 |  2 ++
 target/arm/cpu64.c               | 38 +++++++++++++++++++++++---------
 tests/qtest/arm-cpu-features.c   | 15 +++++++++----
 9 files changed, 66 insertions(+), 22 deletions(-)