arch/s390/Kconfig - arm/linux - Git at Google


            
            # SPDX-License-Identifier: GPL-2.0

            
            config MMU

            
            	def_bool y


            config ZONE_DMA

            
            	def_bool y


            config CPU_BIG_ENDIAN

            
            	def_bool y


            config LOCKDEP_SUPPORT

            
            	def_bool y


            config STACKTRACE_SUPPORT

            
            	def_bool y


            config RWSEM_GENERIC_SPINLOCK

            
            	bool


            config RWSEM_XCHGADD_ALGORITHM

            
            	def_bool y


            config ARCH_HAS_ILOG2_U32

            
            	def_bool n


            config ARCH_HAS_ILOG2_U64

            
            	def_bool n


            config GENERIC_HWEIGHT

            
            	def_bool y


            config GENERIC_BUG

            
            	def_bool y if BUG


            config GENERIC_BUG_RELATIVE_POINTERS

            
            	def_bool y


            config ARCH_DMA_ADDR_T_64BIT

            
            	def_bool y


            config GENERIC_LOCKBREAK

            
            	def_bool y if SMP && PREEMPT


            config PGSTE

            
            	def_bool y if KVM


            config ARCH_SUPPORTS_DEBUG_PAGEALLOC

            
            	def_bool y


            config KEXEC

            
            	def_bool y

            
            	select KEXEC_CORE


            config AUDIT_ARCH

            
            	def_bool y


            config NO_IOPORT_MAP

            
            	def_bool y


            config PCI_QUIRKS

            
            	def_bool n


            config ARCH_SUPPORTS_UPROBES

            
            	def_bool y


            config S390

            
            	def_bool y

            
            	select ARCH_BINFMT_ELF_STATE

            
            	select ARCH_HAS_DEVMEM_IS_ALLOWED

            
            	select ARCH_HAS_ELF_RANDOMIZE

            
            	select ARCH_HAS_GCOV_PROFILE_ALL

            
            	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA

            
            	select ARCH_HAS_KCOV

            
            	select ARCH_HAS_SET_MEMORY

            
            	select ARCH_HAS_SG_CHAIN

            
            	select ARCH_HAS_STRICT_KERNEL_RWX

            
            	select ARCH_HAS_STRICT_MODULE_RWX

            
            	select ARCH_HAS_UBSAN_SANITIZE_ALL

            
            	select ARCH_HAVE_NMI_SAFE_CMPXCHG

            
            	select ARCH_INLINE_READ_LOCK

            
            	select ARCH_INLINE_READ_LOCK_BH

            
            	select ARCH_INLINE_READ_LOCK_IRQ

            
            	select ARCH_INLINE_READ_LOCK_IRQSAVE

            
            	select ARCH_INLINE_READ_TRYLOCK

            
            	select ARCH_INLINE_READ_UNLOCK

            
            	select ARCH_INLINE_READ_UNLOCK_BH

            
            	select ARCH_INLINE_READ_UNLOCK_IRQ

            
            	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE

            
            	select ARCH_INLINE_SPIN_LOCK

            
            	select ARCH_INLINE_SPIN_LOCK_BH

            
            	select ARCH_INLINE_SPIN_LOCK_IRQ

            
            	select ARCH_INLINE_SPIN_LOCK_IRQSAVE

            
            	select ARCH_INLINE_SPIN_TRYLOCK

            
            	select ARCH_INLINE_SPIN_TRYLOCK_BH

            
            	select ARCH_INLINE_SPIN_UNLOCK

            
            	select ARCH_INLINE_SPIN_UNLOCK_BH

            
            	select ARCH_INLINE_SPIN_UNLOCK_IRQ

            
            	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE

            
            	select ARCH_INLINE_WRITE_LOCK

            
            	select ARCH_INLINE_WRITE_LOCK_BH

            
            	select ARCH_INLINE_WRITE_LOCK_IRQ

            
            	select ARCH_INLINE_WRITE_LOCK_IRQSAVE

            
            	select ARCH_INLINE_WRITE_TRYLOCK

            
            	select ARCH_INLINE_WRITE_UNLOCK

            
            	select ARCH_INLINE_WRITE_UNLOCK_BH

            
            	select ARCH_INLINE_WRITE_UNLOCK_IRQ

            
            	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE

            
            	select ARCH_SAVE_PAGE_KEYS if HIBERNATION

            
            	select ARCH_SUPPORTS_ATOMIC_RMW

            
            	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT

            
            	select ARCH_SUPPORTS_NUMA_BALANCING

            
            	select ARCH_USE_BUILTIN_BSWAP

            
            	select ARCH_USE_CMPXCHG_LOCKREF

            
            	select ARCH_WANTS_DYNAMIC_TASK_STRUCT

            
            	select ARCH_WANTS_PROT_NUMA_PROT_NONE

            
            	select ARCH_WANTS_UBSAN_NO_NULL

            
            	select ARCH_WANT_IPC_PARSE_VERSION

            
            	select BUILDTIME_EXTABLE_SORT

            
            	select CLONE_BACKWARDS2

            
            	select DYNAMIC_FTRACE if FUNCTION_TRACER

            
            	select GENERIC_CLOCKEVENTS

            
            	select GENERIC_CPU_AUTOPROBE

            
            	select GENERIC_CPU_DEVICES if !SMP

            
            	select GENERIC_FIND_FIRST_BIT

            
            	select GENERIC_SMP_IDLE_THREAD

            
            	select GENERIC_TIME_VSYSCALL

            
            	select HAVE_ALIGNED_STRUCT_PAGE if SLUB

            
            	select HAVE_ARCH_AUDITSYSCALL

            
            	select HAVE_ARCH_JUMP_LABEL

            
            	select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES

            
            	select HAVE_ARCH_SECCOMP_FILTER

            
            	select HAVE_ARCH_SOFT_DIRTY

            
            	select HAVE_ARCH_TRACEHOOK

            
            	select HAVE_ARCH_TRANSPARENT_HUGEPAGE

            
            	select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES

            
            	select HAVE_CMPXCHG_DOUBLE

            
            	select HAVE_CMPXCHG_LOCAL

            
            	select HAVE_COPY_THREAD_TLS

            
            	select HAVE_DEBUG_KMEMLEAK

            
            	select HAVE_DMA_API_DEBUG

            
            	select HAVE_DMA_CONTIGUOUS

            
            	select DMA_NOOP_OPS

            
            	select HAVE_DYNAMIC_FTRACE

            
            	select HAVE_DYNAMIC_FTRACE_WITH_REGS

            
            	select HAVE_EFFICIENT_UNALIGNED_ACCESS

            
            	select HAVE_EXIT_THREAD

            
            	select HAVE_FTRACE_MCOUNT_RECORD

            
            	select HAVE_FUNCTION_GRAPH_TRACER

            
            	select HAVE_FUNCTION_TRACER

            
            	select HAVE_FUTEX_CMPXCHG if FUTEX

            
            	select HAVE_KERNEL_BZIP2

            
            	select HAVE_KERNEL_GZIP

            
            	select HAVE_KERNEL_LZ4

            
            	select HAVE_KERNEL_LZMA

            
            	select HAVE_KERNEL_LZO

            
            	select HAVE_KERNEL_XZ

            
            	select HAVE_KPROBES

            
            	select HAVE_KRETPROBES

            
            	select HAVE_KVM

            
            	select HAVE_LIVEPATCH

            
            	select HAVE_MEMBLOCK

            
            	select HAVE_MEMBLOCK_NODE_MAP

            
            	select HAVE_MEMBLOCK_PHYS_MAP

            
            	select HAVE_MOD_ARCH_SPECIFIC

            
            	select HAVE_OPROFILE

            
            	select HAVE_PERF_EVENTS

            
            	select HAVE_REGS_AND_STACK_ACCESS_API

            
            	select HAVE_SYSCALL_TRACEPOINTS

            
            	select HAVE_VIRT_CPU_ACCOUNTING

            
            	select MODULES_USE_ELF_RELA

            
            	select NO_BOOTMEM

            
            	select OLD_SIGACTION

            
            	select OLD_SIGSUSPEND3

            
            	select SPARSE_IRQ

            
            	select SYSCTL_EXCEPTION_TRACE

            
            	select THREAD_INFO_IN_TASK

            
            	select TTY

            
            	select VIRT_CPU_ACCOUNTING

            
            	select ARCH_HAS_SCALED_CPUTIME

            
            	select VIRT_TO_BUS

            
            	select HAVE_NMI


            config SCHED_OMIT_FRAME_POINTER

            
            	def_bool y


            config PGTABLE_LEVELS

            
            	int

            
            	default 5


            source "init/Kconfig"


            source "kernel/Kconfig.freezer"


            source "kernel/livepatch/Kconfig"


            menu "Processor type and features"


            config HAVE_MARCH_Z900_FEATURES

            
            	def_bool n


            config HAVE_MARCH_Z990_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z900_FEATURES


            config HAVE_MARCH_Z9_109_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z990_FEATURES


            config HAVE_MARCH_Z10_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z9_109_FEATURES


            config HAVE_MARCH_Z196_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z10_FEATURES


            config HAVE_MARCH_ZEC12_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z196_FEATURES


            config HAVE_MARCH_Z13_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_ZEC12_FEATURES


            config HAVE_MARCH_Z14_FEATURES

            
            	def_bool n

            
            	select HAVE_MARCH_Z13_FEATURES


            choice

            
            	prompt "Processor type"

            
            	default MARCH_Z196


            config MARCH_Z900

            
            	bool "IBM zSeries model z800 and z900"

            
            	select HAVE_MARCH_Z900_FEATURES

            
            	help

            
            	  Select this to enable optimizations for model z800/z900 (2064 and

            
            	  2066 series). This will enable some optimizations that are not

            
            	  available on older ESA/390 (31 Bit) only CPUs.


            config MARCH_Z990

            
            	bool "IBM zSeries model z890 and z990"

            
            	select HAVE_MARCH_Z990_FEATURES

            
            	help

            
            	  Select this to enable optimizations for model z890/z990 (2084 and

            
            	  2086 series). The kernel will be slightly faster but will not work

            
            	  on older machines.


            config MARCH_Z9_109

            
            	bool "IBM System z9"

            
            	select HAVE_MARCH_Z9_109_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM System z9 (2094 and

            
            	  2096 series). The kernel will be slightly faster but will not work

            
            	  on older machines.


            config MARCH_Z10

            
            	bool "IBM System z10"

            
            	select HAVE_MARCH_Z10_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM System z10 (2097 and

            
            	  2098 series). The kernel will be slightly faster but will not work

            
            	  on older machines.


            config MARCH_Z196

            
            	bool "IBM zEnterprise 114 and 196"

            
            	select HAVE_MARCH_Z196_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM zEnterprise 114 and 196

            
            	  (2818 and 2817 series). The kernel will be slightly faster but will

            
            	  not work on older machines.


            config MARCH_ZEC12

            
            	bool "IBM zBC12 and zEC12"

            
            	select HAVE_MARCH_ZEC12_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and

            
            	  2827 series). The kernel will be slightly faster but will not work on

            
            	  older machines.


            config MARCH_Z13

            
            	bool "IBM z13s and z13"

            
            	select HAVE_MARCH_Z13_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM z13s and z13 (2965 and

            
            	  2964 series). The kernel will be slightly faster but will not work on

            
            	  older machines.


            config MARCH_Z14

            
            	bool "IBM z14"

            
            	select HAVE_MARCH_Z14_FEATURES

            
            	help

            
            	  Select this to enable optimizations for IBM z14 (3906 series).

            
            	  The kernel will be slightly faster but will not work on older

            
            	  machines.


            endchoice


            config MARCH_Z900_TUNE

            
            	def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT


            config MARCH_Z990_TUNE

            
            	def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT


            config MARCH_Z9_109_TUNE

            
            	def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT


            config MARCH_Z10_TUNE

            
            	def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT


            config MARCH_Z196_TUNE

            
            	def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT


            config MARCH_ZEC12_TUNE

            
            	def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT


            config MARCH_Z13_TUNE

            
            	def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT


            config MARCH_Z14_TUNE

            
            	def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT


            choice

            
            	prompt "Tune code generation"

            
            	default TUNE_DEFAULT

            
            	help

            
            	  Cause the compiler to tune (-mtune) the generated code for a machine.

            
            	  This will make the code run faster on the selected machine but

            
            	  somewhat slower on other machines.

            
            	  This option only changes how the compiler emits instructions, not the

            
            	  selection of instructions itself, so the resulting kernel will run on

            
            	  all other machines.


            config TUNE_DEFAULT

            
            	bool "Default"

            
            	help

            
            	  Tune the generated code for the target processor for which the kernel

            
            	  will be compiled.


            config TUNE_Z900

            
            	bool "IBM zSeries model z800 and z900"


            config TUNE_Z990

            
            	bool "IBM zSeries model z890 and z990"


            config TUNE_Z9_109

            
            	bool "IBM System z9"


            config TUNE_Z10

            
            	bool "IBM System z10"


            config TUNE_Z196

            
            	bool "IBM zEnterprise 114 and 196"


            config TUNE_ZEC12

            
            	bool "IBM zBC12 and zEC12"


            config TUNE_Z13

            
            	bool "IBM z13"


            config TUNE_Z14

            
            	bool "IBM z14"


            endchoice


            config 64BIT

            
            	def_bool y


            config COMPAT

            
            	def_bool y

            
            	prompt "Kernel support for 31 bit emulation"

            
            	select COMPAT_BINFMT_ELF if BINFMT_ELF

            
            	select ARCH_WANT_OLD_COMPAT_IPC

            
            	select COMPAT_OLD_SIGACTION

            
            	depends on MULTIUSER

            
            	help

            
            	  Select this option if you want to enable your system kernel to

            
            	  handle system-calls from ELF binaries for 31 bit ESA.  This option

            
            	  (and some other stuff like libraries and such) is needed for

            
            	  executing 31 bit applications.  It is safe to say "Y".


            config SYSVIPC_COMPAT

            
            	def_bool y if COMPAT && SYSVIPC


            config SMP

            
            	def_bool y

            
            	prompt "Symmetric multi-processing support"

            
            	---help---

            
            	  This enables support for systems with more than one CPU. If you have

            
            	  a system with only one CPU, like most personal computers, say N. If

            
            	  you have a system with more than one CPU, say Y.


            	  If you say N here, the kernel will run on uni- 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,

            
            	  uniprocessor machines. On a uniprocessor machine, the kernel

            
            	  will run faster if you say N here.


            	  See also the SMP-HOWTO available at

            
            	  <http://www.tldp.org/docs.html#howto>.


            	  Even if you don't know what to do here, say Y.


            config NR_CPUS

            
            	int "Maximum number of CPUs (2-512)"

            
            	range 2 512

            
            	depends on SMP

            
            	default "64"

            
            	help

            
            	  This allows you to specify the maximum number of CPUs which this

            
            	  kernel will support. The maximum supported value is 512 and the

            
            	  minimum value which makes sense is 2.


            	  This is purely to save memory - each supported CPU adds

            
            	  approximately sixteen kilobytes to the kernel image.


            config HOTPLUG_CPU

            
            	def_bool y

            
            	prompt "Support for hot-pluggable CPUs"

            
            	depends on SMP

            
            	help

            
            	  Say Y here to be able to turn CPUs off and on. CPUs

            
            	  can be controlled through /sys/devices/system/cpu/cpu#.

            
            	  Say N if you want to disable CPU hotplug.


            # Some NUMA nodes have memory ranges that span

            
            # other nodes.	Even though a pfn is valid and

            
            # between a node's start and end pfns, it may not

            
            # reside on that node.	See memmap_init_zone()

            
            # for details. <- They meant memory holes!

            
            config NODES_SPAN_OTHER_NODES

            
            	def_bool NUMA


            config NUMA

            
            	bool "NUMA support"

            
            	depends on SMP && SCHED_TOPOLOGY

            
            	default n

            
            	help

            
            	  Enable NUMA support


            	  This option adds NUMA support to the kernel.


            	  An operation mode can be selected by appending

            
            	  numa=<method> to the kernel command line.


            	  The default behaviour is identical to appending numa=plain to

            
            	  the command line. This will create just one node with all

            
            	  available memory and all CPUs in it.


            config NODES_SHIFT

            
            	int "Maximum NUMA nodes (as a power of 2)"

            
            	range 1 10

            
            	depends on NUMA

            
            	default "4"

            
            	help

            
            	  Specify the maximum number of NUMA nodes available on the target

            
            	  system. Increases memory reserved to accommodate various tables.


            menu "Select NUMA modes"

            
            	depends on NUMA


            config NUMA_EMU

            
            	bool "NUMA emulation"

            
            	default y

            
            	help

            
            	  Numa emulation mode will split the available system memory into

            
            	  equal chunks which then are distributed over the configured number

            
            	  of nodes in a round-robin manner.


            	  The number of fake nodes is limited by the number of available memory

            
            	  chunks (i.e. memory size / fake size) and the number of supported

            
            	  nodes in the kernel.


            	  The CPUs are assigned to the nodes in a way that partially respects

            
            	  the original machine topology (if supported by the machine).

            
            	  Fair distribution of the CPUs is not guaranteed.


            config EMU_SIZE

            
            	hex "NUMA emulation memory chunk size"

            
            	default 0x10000000

            
            	range 0x400000 0x100000000

            
            	depends on NUMA_EMU

            
            	help

            
            	  Select the default size by which the memory is chopped and then

            
            	  assigned to emulated NUMA nodes.


            	  This can be overridden by specifying


            	  emu_size=<n>


            	  on the kernel command line where also suffixes K, M, G, and T are

            
            	  supported.


            endmenu


            config SCHED_SMT

            
            	def_bool n


            config SCHED_MC

            
            	def_bool n


            config SCHED_BOOK

            
            	def_bool n


            config SCHED_DRAWER

            
            	def_bool n


            config SCHED_TOPOLOGY

            
            	def_bool y

            
            	prompt "Topology scheduler support"

            
            	depends on SMP

            
            	select SCHED_SMT

            
            	select SCHED_MC

            
            	select SCHED_BOOK

            
            	select SCHED_DRAWER

            
            	help

            
            	  Topology scheduler support improves the CPU scheduler's decision

            
            	  making when dealing with machines that have multi-threading,

            
            	  multiple cores or multiple books.


            source kernel/Kconfig.preempt


            source kernel/Kconfig.hz


            config ARCH_RANDOM

            
            	def_bool y

            
            	prompt "s390 architectural random number generation API"

            
            	help

            
            	  Enable the s390 architectural random number generation API

            
            	  to provide random data for all consumers within the Linux

            
            	  kernel.


            	  When enabled the arch_random_* functions declared in linux/random.h

            
            	  are implemented. The implementation is based on the s390 CPACF

            
            	  instruction subfunction TRNG which provides a real true random

            
            	  number generator.


            	  If unsure, say Y.


            endmenu


            menu "Memory setup"


            config ARCH_SPARSEMEM_ENABLE

            
            	def_bool y

            
            	select SPARSEMEM_VMEMMAP_ENABLE

            
            	select SPARSEMEM_VMEMMAP


            config ARCH_SPARSEMEM_DEFAULT

            
            	def_bool y


            config ARCH_SELECT_MEMORY_MODEL

            
            	def_bool y


            config ARCH_ENABLE_MEMORY_HOTPLUG

            
            	def_bool y if SPARSEMEM


            config ARCH_ENABLE_MEMORY_HOTREMOVE

            
            	def_bool y


            config ARCH_ENABLE_SPLIT_PMD_PTLOCK

            
            	def_bool y


            config FORCE_MAX_ZONEORDER

            
            	int

            
            	default "9"


            source "mm/Kconfig"


            config MAX_PHYSMEM_BITS

            
            	int "Maximum size of supported physical memory in bits (42-53)"

            
            	range 42 53

            
            	default "46"

            
            	help

            
            	  This option specifies the maximum supported size of physical memory

            
            	  in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).

            
            	  Increasing the number of bits also increases the kernel image size.

            
            	  By default 46 bits (64TB) are supported.


            config PACK_STACK

            
            	def_bool y

            
            	prompt "Pack kernel stack"

            
            	help

            
            	  This option enables the compiler option -mkernel-backchain if it

            
            	  is available. If the option is available the compiler supports

            
            	  the new stack layout which dramatically reduces the minimum stack

            
            	  frame size. With an old compiler a non-leaf function needs a

            
            	  minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With

            
            	  -mkernel-backchain the minimum size drops to 16 byte on 31 bit

            
            	  and 24 byte on 64 bit.


            	  Say Y if you are unsure.


            config CHECK_STACK

            
            	def_bool y

            
            	prompt "Detect kernel stack overflow"

            
            	help

            
            	  This option enables the compiler option -mstack-guard and

            
            	  -mstack-size if they are available. If the compiler supports them

            
            	  it will emit additional code to each function prolog to trigger

            
            	  an illegal operation if the kernel stack is about to overflow.


            	  Say N if you are unsure.


            config STACK_GUARD

            
            	int "Size of the guard area (128-1024)"

            
            	range 128 1024

            
            	depends on CHECK_STACK

            
            	default "256"

            
            	help

            
            	  This allows you to specify the size of the guard area at the lower

            
            	  end of the kernel stack. If the kernel stack points into the guard

            
            	  area on function entry an illegal operation is triggered. The size

            
            	  needs to be a power of 2. Please keep in mind that the size of an

            
            	  interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.

            
            	  The minimum size for the stack guard should be 256 for 31 bit and

            
            	  512 for 64 bit.


            config WARN_DYNAMIC_STACK

            
            	def_bool n

            
            	prompt "Emit compiler warnings for function with dynamic stack usage"

            
            	help

            
            	  This option enables the compiler option -mwarn-dynamicstack. If the

            
            	  compiler supports this options generates warnings for functions

            
            	  that dynamically allocate stack space using alloca.


            	  Say N if you are unsure.


            endmenu


            menu "I/O subsystem"


            config QDIO

            
            	def_tristate y

            
            	prompt "QDIO support"

            
            	---help---

            
            	  This driver provides the Queued Direct I/O base support for

            
            	  IBM System z.


            	  To compile this driver as a module, choose M here: the

            
            	  module will be called qdio.


            	  If unsure, say Y.


            menuconfig PCI

            
            	bool "PCI support"

            
            	select PCI_MSI

            
            	select IOMMU_SUPPORT

            
            	help

            
            	  Enable PCI support.


            if PCI


            config PCI_NR_FUNCTIONS

            
            	int "Maximum number of PCI functions (1-4096)"

            
            	range 1 4096

            
            	default "128"

            
            	help

            
            	  This allows you to specify the maximum number of PCI functions which

            
            	  this kernel will support.


            source "drivers/pci/Kconfig"


            endif	# PCI


            config PCI_DOMAINS

            
            	def_bool PCI


            config HAS_IOMEM

            
            	def_bool PCI


            config IOMMU_HELPER

            
            	def_bool PCI


            config NEED_SG_DMA_LENGTH

            
            	def_bool PCI


            config NEED_DMA_MAP_STATE

            
            	def_bool PCI


            config CHSC_SCH

            
            	def_tristate m

            
            	prompt "Support for CHSC subchannels"

            
            	help

            
            	  This driver allows usage of CHSC subchannels. A CHSC subchannel

            
            	  is usually present on LPAR only.

            
            	  The driver creates a device /dev/chsc, which may be used to

            
            	  obtain I/O configuration information about the machine and

            
            	  to issue asynchronous chsc commands (DANGEROUS).

            
            	  You will usually only want to use this interface on a special

            
            	  LPAR designated for system management.


            	  To compile this driver as a module, choose M here: the

            
            	  module will be called chsc_sch.


            	  If unsure, say N.


            config SCM_BUS

            
            	def_bool y

            
            	prompt "SCM bus driver"

            
            	help

            
            	  Bus driver for Storage Class Memory.


            config EADM_SCH

            
            	def_tristate m

            
            	prompt "Support for EADM subchannels"

            
            	depends on SCM_BUS

            
            	help

            
            	  This driver allows usage of EADM subchannels. EADM subchannels act

            
            	  as a communication vehicle for SCM increments.


            	  To compile this driver as a module, choose M here: the

            
            	  module will be called eadm_sch.


            config VFIO_CCW

            
            	def_tristate n

            
            	prompt "Support for VFIO-CCW subchannels"

            
            	depends on S390_CCW_IOMMU && VFIO_MDEV

            
            	help

            
            	  This driver allows usage of I/O subchannels via VFIO-CCW.


            	  To compile this driver as a module, choose M here: the

            
            	  module will be called vfio_ccw.


            endmenu


            menu "Dump support"


            config CRASH_DUMP

            
            	bool "kernel crash dumps"

            
            	depends on SMP

            
            	select KEXEC

            
            	help

            
            	  Generate crash dump after being started by kexec.

            
            	  Crash dump kernels are loaded in the main kernel with kexec-tools

            
            	  into a specially reserved region and then later executed after

            
            	  a crash by kdump/kexec.

            
            	  Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.

            
            	  This option also enables s390 zfcpdump.

            
            	  See also <file:Documentation/s390/zfcpdump.txt>


            endmenu


            menu "Executable file formats / Emulations"


            source "fs/Kconfig.binfmt"


            config SECCOMP

            
            	def_bool y

            
            	prompt "Enable seccomp to safely compute untrusted bytecode"

            
            	depends on PROC_FS

            
            	help

            
            	  This kernel feature is useful for number crunching applications

            
            	  that may need to compute untrusted bytecode during their

            
            	  execution. By using pipes or other transports made available to

            
            	  the process as file descriptors supporting the read/write

            
            	  syscalls, it's possible to isolate those applications in

            
            	  their own address space using seccomp. Once seccomp is

            
            	  enabled via /proc/<pid>/seccomp, it cannot be disabled

            
            	  and the task is only allowed to execute a few safe syscalls

            
            	  defined by each seccomp mode.


            	  If unsure, say Y.


            endmenu


            menu "Power Management"


            config ARCH_HIBERNATION_POSSIBLE

            
            	def_bool y


            source "kernel/power/Kconfig"


            endmenu


            source "net/Kconfig"


            config PCMCIA

            
            	def_bool n


            config CCW

            
            	def_bool y


            source "drivers/Kconfig"


            source "fs/Kconfig"


            source "arch/s390/Kconfig.debug"


            source "security/Kconfig"


            source "crypto/Kconfig"


            source "lib/Kconfig"


            menu "Virtualization"


            config PFAULT

            
            	def_bool y

            
            	prompt "Pseudo page fault support"

            
            	help

            
            	  Select this option, if you want to use PFAULT pseudo page fault

            
            	  handling under VM. If running native or in LPAR, this option

            
            	  has no effect. If your VM does not support PFAULT, PAGEEX

            
            	  pseudo page fault handling will be used.

            
            	  Note that VM 4.2 supports PFAULT but has a bug in its

            
            	  implementation that causes some problems.

            
            	  Everybody who wants to run Linux under VM != VM4.2 should select

            
            	  this option.


            config SHARED_KERNEL

            
            	bool "VM shared kernel support"

            
            	depends on !JUMP_LABEL

            
            	help

            
            	  Select this option, if you want to share the text segment of the

            
            	  Linux kernel between different VM guests. This reduces memory

            
            	  usage with lots of guests but greatly increases kernel size.

            
            	  Also if a kernel was IPL'ed from a shared segment the kexec system

            
            	  call will not work.

            
            	  You should only select this option if you know what you are

            
            	  doing and want to exploit this feature.


            config CMM

            
            	def_tristate n

            
            	prompt "Cooperative memory management"

            
            	help

            
            	  Select this option, if you want to enable the kernel interface

            
            	  to reduce the memory size of the system. This is accomplished

            
            	  by allocating pages of memory and put them "on hold". This only

            
            	  makes sense for a system running under VM where the unused pages

            
            	  will be reused by VM for other guest systems. The interface

            
            	  allows an external monitor to balance memory of many systems.

            
            	  Everybody who wants to run Linux under VM should select this

            
            	  option.


            config CMM_IUCV

            
            	def_bool y

            
            	prompt "IUCV special message interface to cooperative memory management"

            
            	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)

            
            	help

            
            	  Select this option to enable the special message interface to

            
            	  the cooperative memory management.


            config APPLDATA_BASE

            
            	def_bool n

            
            	prompt "Linux - VM Monitor Stream, base infrastructure"

            
            	depends on PROC_FS

            
            	help

            
            	  This provides a kernel interface for creating and updating z/VM APPLDATA

            
            	  monitor records. The monitor records are updated at certain time

            
            	  intervals, once the timer is started.

            
            	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,

            
            	  i.e. enables or disables monitoring on the Linux side.

            
            	  A custom interval value (in seconds) can be written to

            
            	  /proc/appldata/interval.


            	  Defaults are 60 seconds interval and timer off.

            
            	  The /proc entries can also be read from, showing the current settings.


            config APPLDATA_MEM

            
            	def_tristate m

            
            	prompt "Monitor memory management statistics"

            
            	depends on APPLDATA_BASE && VM_EVENT_COUNTERS

            
            	help

            
            	  This provides memory management related data to the Linux - VM Monitor

            
            	  Stream, like paging/swapping rate, memory utilisation, etc.

            
            	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM

            
            	  APPLDATA monitor record, i.e. enables or disables monitoring this record

            
            	  on the z/VM side.


            	  Default is disabled.

            
            	  The /proc entry can also be read from, showing the current settings.


            	  This can also be compiled as a module, which will be called

            
            	  appldata_mem.o.


            config APPLDATA_OS

            
            	def_tristate m

            
            	prompt "Monitor OS statistics"

            
            	depends on APPLDATA_BASE

            
            	help

            
            	  This provides OS related data to the Linux - VM Monitor Stream, like

            
            	  CPU utilisation, etc.

            
            	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM

            
            	  APPLDATA monitor record, i.e. enables or disables monitoring this record

            
            	  on the z/VM side.


            	  Default is disabled.

            
            	  This can also be compiled as a module, which will be called

            
            	  appldata_os.o.


            config APPLDATA_NET_SUM

            
            	def_tristate m

            
            	prompt "Monitor overall network statistics"

            
            	depends on APPLDATA_BASE && NET

            
            	help

            
            	  This provides network related data to the Linux - VM Monitor Stream,

            
            	  currently there is only a total sum of network I/O statistics, no

            
            	  per-interface data.

            
            	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM

            
            	  APPLDATA monitor record, i.e. enables or disables monitoring this record

            
            	  on the z/VM side.


            	  Default is disabled.

            
            	  This can also be compiled as a module, which will be called

            
            	  appldata_net_sum.o.


            config S390_HYPFS_FS

            
            	def_bool y

            
            	prompt "s390 hypervisor file system support"

            
            	select SYS_HYPERVISOR

            
            	help

            
            	  This is a virtual file system intended to provide accounting

            
            	  information in an s390 hypervisor environment.


            source "arch/s390/kvm/Kconfig"


            config S390_GUEST

            
            	def_bool y

            
            	prompt "s390 support for virtio devices"

            
            	select TTY

            
            	select VIRTUALIZATION

            
            	select VIRTIO

            
            	select VIRTIO_CONSOLE

            
            	help

            
            	  Enabling this option adds support for virtio based paravirtual device

            
            	  drivers on s390.


            	  Select this option if you want to run the kernel as a guest under

            
            	  the KVM hypervisor.


            config S390_GUEST_OLD_TRANSPORT

            
            	def_bool y

            
            	prompt "Guest support for old s390 virtio transport (DEPRECATED)"

            
            	depends on S390_GUEST

            
            	help

            
            	  Enable this option to add support for the old s390-virtio

            
            	  transport (i.e. virtio devices NOT based on virtio-ccw). This

            
            	  type of virtio devices is only available on the experimental

            
            	  kuli userspace or with old (< 2.6) qemu. If you are running

            
            	  with a modern version of qemu (which supports virtio-ccw since

            
            	  1.4 and uses it by default since version 2.4), you probably won't

            
            	  need this.


            endmenu