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-rw-r--r--arch/arm64/Kconfig48
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9af67474016..4b94ed4aad9 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -12,6 +12,7 @@ config ARM64
select ARM_ARCH_TIMER
select ARM_GIC
select BUILDTIME_EXTABLE_SORT
+ select AUDIT_ARCH_COMPAT_GENERIC
select CLONE_BACKWARDS
select COMMON_CLK
select CPU_PM if (SUSPEND || CPU_IDLE)
@@ -30,6 +31,7 @@ config ARM64
select HARDIRQS_SW_RESEND
select HAVE_ARCH_JUMP_LABEL
select HAVE_ARCH_KGDB
+ select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_TRACEHOOK
select HAVE_C_RECORDMCOUNT
select HAVE_DEBUG_BUGVERBOSE
@@ -304,6 +306,31 @@ config HOTPLUG_CPU
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
+config SWP_EMULATE
+ bool "Emulate SWP/SWPB instructions"
+ help
+ ARMv6 architecture deprecates use of the SWP/SWPB instructions. ARMv8
+ oblosetes the use of SWP/SWPB instructions. ARMv7 multiprocessing
+ extensions introduce the ability to disable these instructions,
+ triggering an undefined instruction exception when executed. Say Y
+ here to enable software emulation of these instructions for userspace
+ (not kernel) using LDREX/STREX. Also creates /proc/cpu/swp_emulation
+ for statistics.
+
+ In some older versions of glibc [<=2.8] SWP is used during futex
+ trylock() operations with the assumption that the code will not
+ be preempted. This invalid assumption may be more likely to fail
+ with SWP emulation enabled, leading to deadlock of the user
+ application.
+
+ NOTE: when accessing uncached shared regions, LDREX/STREX rely
+ on an external transaction monitoring block called a global
+ monitor to maintain update atomicity. If your system does not
+ implement a global monitor, this option can cause programs that
+ perform SWP operations to uncached memory to deadlock.
+
+ If unsure, say Y.
+
source kernel/Kconfig.preempt
config HZ
@@ -346,6 +373,27 @@ config ARCH_WANT_HUGE_PMD_SHARE
config HAVE_ARCH_TRANSPARENT_HUGEPAGE
def_bool y
+config ARMV7_COMPAT
+ bool "Kernel support for ARMv7 applications"
+ depends on COMPAT
+ select SWP_EMULATE
+ help
+ This option enables features that allow that ran on an ARMv7 or older
+ processor to continue functioning.
+
+ If you want to execute ARMv7 applications, say Y
+
+config ARMV7_COMPAT_CPUINFO
+ bool "Report backwards compatible cpu features in /proc/cpuinfo"
+ depends on ARMV7_COMPAT
+ default y
+ help
+ This option makes /proc/cpuinfo list CPU features that an ARMv7 or
+ earlier kernel would report, but are not optional on an ARMv8 or later
+ processor.
+
+ If you want to execute ARMv7 applications, say Y
+
source "mm/Kconfig"
config FORCE_MAX_ZONEORDER