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-rw-r--r--arch/arm64/Kconfig86
1 files changed, 64 insertions, 22 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 51832ad33fa9..7d95663c0160 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -29,7 +29,7 @@ config ARM64
select EDAC_SUPPORT
select GENERIC_ALLOCATOR
select GENERIC_CLOCKEVENTS
- select GENERIC_CLOCKEVENTS_BROADCAST if SMP
+ select GENERIC_CLOCKEVENTS_BROADCAST
select GENERIC_CPU_AUTOPROBE
select GENERIC_EARLY_IOREMAP
select GENERIC_IRQ_PROBE
@@ -54,6 +54,7 @@ config ARM64
select HAVE_C_RECORDMCOUNT
select HAVE_CC_STACKPROTECTOR
select HAVE_CMPXCHG_DOUBLE
+ select HAVE_CMPXCHG_LOCAL
select HAVE_DEBUG_BUGVERBOSE
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_API_DEBUG
@@ -105,6 +106,10 @@ config NO_IOPORT_MAP
config STACKTRACE_SUPPORT
def_bool y
+config ILLEGAL_POINTER_VALUE
+ hex
+ default 0xdead000000000000
+
config LOCKDEP_SUPPORT
def_bool y
@@ -114,6 +119,14 @@ config TRACE_IRQFLAGS_SUPPORT
config RWSEM_XCHGADD_ALGORITHM
def_bool y
+config GENERIC_BUG
+ def_bool y
+ depends on BUG
+
+config GENERIC_BUG_RELATIVE_POINTERS
+ def_bool y
+ depends on GENERIC_BUG
+
config GENERIC_HWEIGHT
def_bool y
@@ -138,6 +151,9 @@ config NEED_DMA_MAP_STATE
config NEED_SG_DMA_LENGTH
def_bool y
+config SMP
+ def_bool y
+
config SWIOTLB
def_bool y
@@ -372,22 +388,8 @@ config CPU_BIG_ENDIAN
help
Say Y if you plan on running a kernel in big-endian mode.
-config SMP
- bool "Symmetric Multi-Processing"
- help
- This enables support for systems with more than one CPU. If
- you say N here, the kernel will run on single and
- multiprocessor machines, but will use only one CPU of a
- multiprocessor machine. If you say Y here, the kernel will run
- on many, but not all, single processor machines. On a single
- processor machine, the kernel will run faster if you say N
- here.
-
- If you don't know what to do here, say N.
-
config SCHED_MC
bool "Multi-core scheduler support"
- depends on SMP
help
Multi-core scheduler support improves the CPU scheduler's decision
making when dealing with multi-core CPU chips at a cost of slightly
@@ -395,7 +397,6 @@ config SCHED_MC
config SCHED_SMT
bool "SMT scheduler support"
- depends on SMP
help
Improves the CPU scheduler's decision making when dealing with
MultiThreading at a cost of slightly increased overhead in some
@@ -404,23 +405,17 @@ config SCHED_SMT
config NR_CPUS
int "Maximum number of CPUs (2-4096)"
range 2 4096
- depends on SMP
# These have to remain sorted largest to smallest
default "64"
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
- depends on SMP
help
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
source kernel/Kconfig.preempt
-config UP_LATE_INIT
- def_bool y
- depends on !SMP
-
config HZ
int
default 100
@@ -562,6 +557,53 @@ config SETEND_EMULATION
If unsure, say Y
endif
+menu "ARMv8.1 architectural features"
+
+config ARM64_HW_AFDBM
+ bool "Support for hardware updates of the Access and Dirty page flags"
+ default y
+ help
+ The ARMv8.1 architecture extensions introduce support for
+ hardware updates of the access and dirty information in page
+ table entries. When enabled in TCR_EL1 (HA and HD bits) on
+ capable processors, accesses to pages with PTE_AF cleared will
+ set this bit instead of raising an access flag fault.
+ Similarly, writes to read-only pages with the DBM bit set will
+ clear the read-only bit (AP[2]) instead of raising a
+ permission fault.
+
+ Kernels built with this configuration option enabled continue
+ to work on pre-ARMv8.1 hardware and the performance impact is
+ minimal. If unsure, say Y.
+
+config ARM64_PAN
+ bool "Enable support for Privileged Access Never (PAN)"
+ default y
+ help
+ Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
+ prevents the kernel or hypervisor from accessing user-space (EL0)
+ memory directly.
+
+ Choosing this option will cause any unprotected (not using
+ copy_to_user et al) memory access to fail with a permission fault.
+
+ The feature is detected at runtime, and will remain as a 'nop'
+ instruction if the cpu does not implement the feature.
+
+config ARM64_LSE_ATOMICS
+ bool "Atomic instructions"
+ help
+ As part of the Large System Extensions, ARMv8.1 introduces new
+ atomic instructions that are designed specifically to scale in
+ very large systems.
+
+ Say Y here to make use of these instructions for the in-kernel
+ atomic routines. This incurs a small overhead on CPUs that do
+ not support these instructions and requires the kernel to be
+ built with binutils >= 2.25.
+
+endmenu
+
endmenu
menu "Boot options"