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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
commit8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch)
treee9891aa6c295060d065adffd610c4f49ecf884f3 /arch/x86/Kconfig
parenta71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff)
Linux-libre 4.3.2-gnu
Diffstat (limited to 'arch/x86/Kconfig')
-rw-r--r--arch/x86/Kconfig98
1 files changed, 81 insertions, 17 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b3a1a5d77..a43ae1fa2 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -27,7 +27,8 @@ config X86
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FAST_MULTIPLIER
select ARCH_HAS_GCOV_PROFILE_ALL
- select ARCH_HAS_PMEM_API
+ select ARCH_HAS_PMEM_API if X86_64
+ select ARCH_HAS_MMIO_FLUSH
select ARCH_HAS_SG_CHAIN
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
@@ -41,6 +42,7 @@ config X86
select ARCH_USE_CMPXCHG_LOCKREF if X86_64
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
+ select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
select ARCH_WANTS_DYNAMIC_TASK_STRUCT
select ARCH_WANT_FRAME_POINTERS
select ARCH_WANT_IPC_PARSE_VERSION if X86_32
@@ -133,7 +135,7 @@ config X86
select HAVE_PERF_USER_STACK_DUMP
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_SYSCALL_TRACEPOINTS
- select HAVE_UID16 if X86_32
+ select HAVE_UID16 if X86_32 || IA32_EMULATION
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_USER_RETURN_NOTIFIER
select IRQ_FORCED_THREADING
@@ -875,10 +877,26 @@ config SCHED_SMT
depends on SMP
---help---
SMT scheduler support improves the CPU scheduler's decision making
- when dealing with Intel Pentium 4 chips with HyperThreading at a
+ when dealing with Intel P4/Core 2 chips with HyperThreading at a
cost of slightly increased overhead in some places. If unsure say
N here.
+config SMT_NICE
+ bool "SMT (Hyperthreading) aware nice priority and policy support"
+ depends on SCHED_BFS && SCHED_SMT
+ default y
+ ---help---
+ Enabling Hyperthreading on Intel CPUs decreases the effectiveness
+ of the use of 'nice' levels and different scheduling policies
+ (e.g. realtime) due to sharing of CPU power between hyperthreads.
+ SMT nice support makes each logical CPU aware of what is running on
+ its hyperthread siblings, maintaining appropriate distribution of
+ CPU according to nice levels and scheduling policies at the expense
+ of slightly increased overhead.
+
+ If unsure say Y here.
+
+
config SCHED_MC
def_bool y
prompt "Multi-core scheduler support"
@@ -955,6 +973,7 @@ config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
config X86_MCE
bool "Machine Check / overheating reporting"
+ select GENERIC_ALLOCATOR
default y
---help---
Machine Check support allows the processor to notify the
@@ -1002,19 +1021,42 @@ config X86_THERMAL_VECTOR
def_bool y
depends on X86_MCE_INTEL
-config VM86
- bool "Enable VM86 support" if EXPERT
- default y
+config X86_LEGACY_VM86
+ bool "Legacy VM86 support"
+ default n
depends on X86_32
---help---
- This option is required by programs like DOSEMU to run
- 16-bit real mode legacy code on x86 processors. It also may
- be needed by software like XFree86 to initialize some video
- cards via BIOS. Disabling this option saves about 6K.
+ This option allows user programs to put the CPU into V8086
+ mode, which is an 80286-era approximation of 16-bit real mode.
+
+ Some very old versions of X and/or vbetool require this option
+ for user mode setting. Similarly, DOSEMU will use it if
+ available to accelerate real mode DOS programs. However, any
+ recent version of DOSEMU, X, or vbetool should be fully
+ functional even without kernel VM86 support, as they will all
+ fall back to software emulation. Nevertheless, if you are using
+ a 16-bit DOS program where 16-bit performance matters, vm86
+ mode might be faster than emulation and you might want to
+ enable this option.
+
+ Note that any app that works on a 64-bit kernel is unlikely to
+ need this option, as 64-bit kernels don't, and can't, support
+ V8086 mode. This option is also unrelated to 16-bit protected
+ mode and is not needed to run most 16-bit programs under Wine.
+
+ Enabling this option increases the complexity of the kernel
+ and slows down exception handling a tiny bit.
+
+ If unsure, say N here.
+
+config VM86
+ bool
+ default X86_LEGACY_VM86
config X86_16BIT
bool "Enable support for 16-bit segments" if EXPERT
default y
+ depends on MODIFY_LDT_SYSCALL
---help---
This option is required by programs like Wine to run 16-bit
protected mode legacy code on x86 processors. Disabling
@@ -1282,6 +1324,7 @@ config HIGHMEM
config X86_PAE
bool "PAE (Physical Address Extension) Support"
depends on X86_32 && !HIGHMEM4G
+ select SWIOTLB
---help---
PAE is required for NX support, and furthermore enables
larger swapspace support for non-overcommit purposes. It
@@ -1426,10 +1469,14 @@ config ILLEGAL_POINTER_VALUE
source "mm/Kconfig"
+config X86_PMEM_LEGACY_DEVICE
+ bool
+
config X86_PMEM_LEGACY
- bool "Support non-standard NVDIMMs and ADR protected memory"
+ tristate "Support non-standard NVDIMMs and ADR protected memory"
depends on PHYS_ADDR_T_64BIT
depends on BLK_DEV
+ select X86_PMEM_LEGACY_DEVICE
select LIBNVDIMM
help
Treat memory marked using the non-standard e820 type of 12 as used
@@ -1509,6 +1556,7 @@ config X86_RESERVE_LOW
config MATH_EMULATION
bool
+ depends on MODIFY_LDT_SYSCALL
prompt "Math emulation" if X86_32
---help---
Linux can emulate a math coprocessor (used for floating point
@@ -1724,6 +1772,7 @@ source kernel/Kconfig.hz
config KEXEC
bool "kexec system call"
+ select KEXEC_CORE
---help---
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
@@ -1740,8 +1789,8 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
+ select KEXEC_CORE
select BUILD_BIN2C
- depends on KEXEC
depends on X86_64
depends on CRYPTO=y
depends on CRYPTO_SHA256=y
@@ -1944,7 +1993,7 @@ config HOTPLUG_CPU
config BOOTPARAM_HOTPLUG_CPU0
bool "Set default setting of cpu0_hotpluggable"
default n
- depends on HOTPLUG_CPU
+ depends on HOTPLUG_CPU && !SCHED_BFS
---help---
Set whether default state of cpu0_hotpluggable is on or off.
@@ -1973,7 +2022,7 @@ config BOOTPARAM_HOTPLUG_CPU0
config DEBUG_HOTPLUG_CPU0
def_bool n
prompt "Debug CPU0 hotplug"
- depends on HOTPLUG_CPU
+ depends on HOTPLUG_CPU && !SCHED_BFS
---help---
Enabling this option offlines CPU0 (if CPU0 can be offlined) as
soon as possible and boots up userspace with CPU0 offlined. User
@@ -2053,6 +2102,22 @@ config CMDLINE_OVERRIDE
This is used to work around broken boot loaders. This should
be set to 'N' under normal conditions.
+config MODIFY_LDT_SYSCALL
+ bool "Enable the LDT (local descriptor table)" if EXPERT
+ default y
+ ---help---
+ Linux can allow user programs to install a per-process x86
+ Local Descriptor Table (LDT) using the modify_ldt(2) system
+ call. This is required to run 16-bit or segmented code such as
+ DOSEMU or some Wine programs. It is also used by some very old
+ threading libraries.
+
+ Enabling this feature adds a small amount of overhead to
+ context switches and increases the low-level kernel attack
+ surface. Disabling it removes the modify_ldt(2) system call.
+
+ Saying 'N' here may make sense for embedded or server kernels.
+
source "kernel/livepatch/Kconfig"
endmenu
@@ -2522,7 +2587,7 @@ config IA32_EMULATION
depends on X86_64
select BINFMT_ELF
select COMPAT_BINFMT_ELF
- select HAVE_UID16
+ select ARCH_WANT_OLD_COMPAT_IPC
---help---
Include code to run legacy 32-bit programs under a
64-bit kernel. You should likely turn this on, unless you're
@@ -2536,7 +2601,7 @@ config IA32_AOUT
config X86_X32
bool "x32 ABI for 64-bit mode"
- depends on X86_64 && IA32_EMULATION
+ depends on X86_64
---help---
Include code to run binaries for the x32 native 32-bit ABI
for 64-bit processors. An x32 process gets access to the
@@ -2550,7 +2615,6 @@ config X86_X32
config COMPAT
def_bool y
depends on IA32_EMULATION || X86_X32
- select ARCH_WANT_OLD_COMPAT_IPC
if COMPAT
config COMPAT_FOR_U64_ALIGNMENT