diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2021-01-11 13:57:39 -1000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2021-01-19 14:38:51 +0000 |
| commit | eb94284d0812b4e7c11c5d075b584100ac1c1b9a (patch) | |
| tree | ad205638a5b69b2bfce54899472934b4179db904 /docs | |
| parent | 283fc52ade85eb50141f3b8b85f82b07d016cb17 (diff) | |
target/arm: Add cpu properties to control pauth
The crypto overhead of emulating pauth can be significant for
some workloads. Add two boolean properties that allows the
feature to be turned off, on with the architected algorithm,
or on with an implementation defined algorithm.
We need two intermediate booleans to control the state while
parsing properties lest we clobber ID_AA64ISAR1 into an invalid
intermediate state.
Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210111235740.462469-3-richard.henderson@linaro.org
[PMM: fixed docs typo, tweaked text to clarify that the impdef
algorithm is specific to QEMU]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/system/arm/cpu-features.rst | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst index 35196a6b75..c455442eaf 100644 --- a/docs/system/arm/cpu-features.rst +++ b/docs/system/arm/cpu-features.rst @@ -211,6 +211,27 @@ the list of KVM VCPU features and their descriptions. influence the guest scheduler behavior and/or be exposed to the guest userspace. +TCG VCPU Features +================= + +TCG VCPU features are CPU features that are specific to TCG. +Below is the list of TCG VCPU features and their descriptions. + + pauth Enable or disable `FEAT_Pauth`, pointer + authentication. By default, the feature is + enabled with `-cpu max`. + + pauth-impdef When `FEAT_Pauth` is enabled, either the + *impdef* (Implementation Defined) algorithm + is enabled or the *architected* QARMA algorithm + is enabled. By default the impdef algorithm + is disabled, and QARMA is enabled. + + The architected QARMA algorithm has good + cryptographic properties, but can be quite slow + to emulate. The impdef algorithm used by QEMU + is non-cryptographic but significantly faster. + SVE CPU Properties ================== |