diff options
| -rw-r--r-- | arch/arm64/Kconfig | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 66dc41fd49f2..6c560caf9503 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1327,6 +1327,8 @@ config SWP_EMULATION ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that they are always undefined. Say Y here to enable software emulation of these instructions for userspace using LDXR/STXR. + This feature can be controlled at runtime with the abi.swp + sysctl which is disabled by default. In some older versions of glibc [<=2.8] SWP is used during futex trylock() operations with the assumption that the code will not @@ -1353,7 +1355,8 @@ config CP15_BARRIER_EMULATION Say Y here to enable software emulation of these instructions for AArch32 userspace code. When this option is enabled, CP15 barrier usage is traced which can help - identify software that needs updating. + identify software that needs updating. This feature can be + controlled at runtime with the abi.cp15_barrier sysctl. If unsure, say Y @@ -1364,7 +1367,8 @@ config SETEND_EMULATION AArch32 EL0, and is deprecated in ARMv8. Say Y here to enable software emulation of the instruction - for AArch32 userspace code. + for AArch32 userspace code. This feature can be controlled + at runtime with the abi.setend sysctl. Note: All the cpus on the system must have mixed endian support at EL0 for this feature to be enabled. If a new CPU - which doesn't support mixed |