arch/s390/Kconfig

   1 config MMU
   2         def_bool y
   3
   4 config ZONE_DMA
   5         def_bool y
   6
   7 config CPU_BIG_ENDIAN
   8         def_bool y
   9
  10 config LOCKDEP_SUPPORT
  11         def_bool y
  12
  13 config STACKTRACE_SUPPORT
  14         def_bool y
  15
  16 config RWSEM_GENERIC_SPINLOCK
  17         bool
  18
  19 config RWSEM_XCHGADD_ALGORITHM
  20         def_bool y
  21
  22 config ARCH_HAS_ILOG2_U32
  23         def_bool n
  24
  25 config ARCH_HAS_ILOG2_U64
  26         def_bool n
  27
  28 config GENERIC_HWEIGHT
  29         def_bool y
  30
  31 config GENERIC_BUG
  32         def_bool y if BUG
  33
  34 config GENERIC_BUG_RELATIVE_POINTERS
  35         def_bool y
  36
  37 config ARCH_DMA_ADDR_T_64BIT
  38         def_bool y
  39
  40 config GENERIC_LOCKBREAK
  41         def_bool y if SMP && PREEMPT
  42
  43 config PGSTE
  44         def_bool y if KVM
  45
  46 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  47         def_bool y
  48
  49 config KEXEC
  50         def_bool y
  51         select KEXEC_CORE
  52
  53 config AUDIT_ARCH
  54         def_bool y
  55
  56 config NO_IOPORT_MAP
  57         def_bool y
  58
  59 config PCI_QUIRKS
  60         def_bool n
  61
  62 config ARCH_SUPPORTS_UPROBES
  63         def_bool y
  64
  65 config DEBUG_RODATA
  66         def_bool y
  67
  68 config S390
  69         def_bool y
  70         select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  71         select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
  72         select ARCH_HAS_DEVMEM_IS_ALLOWED
  73         select ARCH_HAS_ELF_RANDOMIZE
  74         select ARCH_HAS_GCOV_PROFILE_ALL
  75         select ARCH_HAS_SG_CHAIN
  76         select ARCH_HAVE_NMI_SAFE_CMPXCHG
  77         select ARCH_INLINE_READ_LOCK
  78         select ARCH_INLINE_READ_LOCK_BH
  79         select ARCH_INLINE_READ_LOCK_IRQ
  80         select ARCH_INLINE_READ_LOCK_IRQSAVE
  81         select ARCH_INLINE_READ_TRYLOCK
  82         select ARCH_INLINE_READ_UNLOCK
  83         select ARCH_INLINE_READ_UNLOCK_BH
  84         select ARCH_INLINE_READ_UNLOCK_IRQ
  85         select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
  86         select ARCH_INLINE_SPIN_LOCK
  87         select ARCH_INLINE_SPIN_LOCK_BH
  88         select ARCH_INLINE_SPIN_LOCK_IRQ
  89         select ARCH_INLINE_SPIN_LOCK_IRQSAVE
  90         select ARCH_INLINE_SPIN_TRYLOCK
  91         select ARCH_INLINE_SPIN_TRYLOCK_BH
  92         select ARCH_INLINE_SPIN_UNLOCK
  93         select ARCH_INLINE_SPIN_UNLOCK_BH
  94         select ARCH_INLINE_SPIN_UNLOCK_IRQ
  95         select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
  96         select ARCH_INLINE_WRITE_LOCK
  97         select ARCH_INLINE_WRITE_LOCK_BH
  98         select ARCH_INLINE_WRITE_LOCK_IRQ
  99         select ARCH_INLINE_WRITE_LOCK_IRQSAVE
 100         select ARCH_INLINE_WRITE_TRYLOCK
 101         select ARCH_INLINE_WRITE_UNLOCK
 102         select ARCH_INLINE_WRITE_UNLOCK_BH
 103         select ARCH_INLINE_WRITE_UNLOCK_IRQ
 104         select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
 105         select ARCH_SAVE_PAGE_KEYS if HIBERNATION
 106         select ARCH_SUPPORTS_ATOMIC_RMW
 107         select ARCH_SUPPORTS_NUMA_BALANCING
 108         select ARCH_USE_BUILTIN_BSWAP
 109         select ARCH_USE_CMPXCHG_LOCKREF
 110         select ARCH_WANTS_PROT_NUMA_PROT_NONE
 111         select ARCH_WANT_IPC_PARSE_VERSION
 112         select BUILDTIME_EXTABLE_SORT
 113         select CLONE_BACKWARDS2
 114         select DYNAMIC_FTRACE if FUNCTION_TRACER
 115         select GENERIC_CLOCKEVENTS
 116         select GENERIC_CPU_AUTOPROBE
 117         select GENERIC_CPU_DEVICES if !SMP
 118         select GENERIC_FIND_FIRST_BIT
 119         select GENERIC_SMP_IDLE_THREAD
 120         select GENERIC_TIME_VSYSCALL
 121         select HAVE_ALIGNED_STRUCT_PAGE if SLUB
 122         select HAVE_ARCH_AUDITSYSCALL
 123         select HAVE_ARCH_EARLY_PFN_TO_NID
 124         select HAVE_ARCH_JUMP_LABEL
 125         select HAVE_ARCH_SECCOMP_FILTER
 126         select HAVE_ARCH_SOFT_DIRTY
 127         select HAVE_ARCH_TRACEHOOK
 128         select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 129         select HAVE_BPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
 130         select HAVE_CMPXCHG_DOUBLE
 131         select HAVE_CMPXCHG_LOCAL
 132         select HAVE_DEBUG_KMEMLEAK
 133         select HAVE_DMA_API_DEBUG
 134         select HAVE_DYNAMIC_FTRACE
 135         select HAVE_DYNAMIC_FTRACE_WITH_REGS
 136         select HAVE_FTRACE_MCOUNT_RECORD
 137         select HAVE_FUNCTION_GRAPH_TRACER
 138         select HAVE_FUNCTION_TRACER
 139         select HAVE_FUTEX_CMPXCHG if FUTEX
 140         select HAVE_KERNEL_BZIP2
 141         select HAVE_KERNEL_GZIP
 142         select HAVE_KERNEL_LZ4
 143         select HAVE_KERNEL_LZMA
 144         select HAVE_KERNEL_LZO
 145         select HAVE_KERNEL_XZ
 146         select HAVE_KPROBES
 147         select HAVE_KRETPROBES
 148         select HAVE_KVM
 149         select HAVE_LIVEPATCH
 150         select HAVE_MEMBLOCK
 151         select HAVE_MEMBLOCK_NODE_MAP
 152         select HAVE_MEMBLOCK_PHYS_MAP
 153         select HAVE_MOD_ARCH_SPECIFIC
 154         select HAVE_OPROFILE
 155         select HAVE_PERF_EVENTS
 156         select HAVE_REGS_AND_STACK_ACCESS_API
 157         select HAVE_SYSCALL_TRACEPOINTS
 158         select HAVE_VIRT_CPU_ACCOUNTING
 159         select MODULES_USE_ELF_RELA
 160         select NO_BOOTMEM
 161         select OLD_SIGACTION
 162         select OLD_SIGSUSPEND3
 163         select SYSCTL_EXCEPTION_TRACE
 164         select TTY
 165         select VIRT_CPU_ACCOUNTING
 166         select VIRT_TO_BUS
 167
 168
 169 config SCHED_OMIT_FRAME_POINTER
 170         def_bool y
 171
 172 config PGTABLE_LEVELS
 173         int
 174         default 4
 175
 176 source "init/Kconfig"
 177
 178 source "kernel/Kconfig.freezer"
 179
 180 source "kernel/livepatch/Kconfig"
 181
 182 menu "Processor type and features"
 183
 184 config HAVE_MARCH_Z900_FEATURES
 185         def_bool n
 186
 187 config HAVE_MARCH_Z990_FEATURES
 188         def_bool n
 189         select HAVE_MARCH_Z900_FEATURES
 190
 191 config HAVE_MARCH_Z9_109_FEATURES
 192         def_bool n
 193         select HAVE_MARCH_Z990_FEATURES
 194
 195 config HAVE_MARCH_Z10_FEATURES
 196         def_bool n
 197         select HAVE_MARCH_Z9_109_FEATURES
 198
 199 config HAVE_MARCH_Z196_FEATURES
 200         def_bool n
 201         select HAVE_MARCH_Z10_FEATURES
 202
 203 config HAVE_MARCH_ZEC12_FEATURES
 204         def_bool n
 205         select HAVE_MARCH_Z196_FEATURES
 206
 207 config HAVE_MARCH_Z13_FEATURES
 208         def_bool n
 209         select HAVE_MARCH_ZEC12_FEATURES
 210
 211 choice
 212         prompt "Processor type"
 213         default MARCH_Z900
 214
 215 config MARCH_Z900
 216         bool "IBM zSeries model z800 and z900"
 217         select HAVE_MARCH_Z900_FEATURES
 218         help
 219           Select this to enable optimizations for model z800/z900 (2064 and
 220           2066 series). This will enable some optimizations that are not
 221           available on older ESA/390 (31 Bit) only CPUs.
 222
 223 config MARCH_Z990
 224         bool "IBM zSeries model z890 and z990"
 225         select HAVE_MARCH_Z990_FEATURES
 226         help
 227           Select this to enable optimizations for model z890/z990 (2084 and
 228           2086 series). The kernel will be slightly faster but will not work
 229           on older machines.
 230
 231 config MARCH_Z9_109
 232         bool "IBM System z9"
 233         select HAVE_MARCH_Z9_109_FEATURES
 234         help
 235           Select this to enable optimizations for IBM System z9 (2094 and
 236           2096 series). The kernel will be slightly faster but will not work
 237           on older machines.
 238
 239 config MARCH_Z10
 240         bool "IBM System z10"
 241         select HAVE_MARCH_Z10_FEATURES
 242         help
 243           Select this to enable optimizations for IBM System z10 (2097 and
 244           2098 series). The kernel will be slightly faster but will not work
 245           on older machines.
 246
 247 config MARCH_Z196
 248         bool "IBM zEnterprise 114 and 196"
 249         select HAVE_MARCH_Z196_FEATURES
 250         help
 251           Select this to enable optimizations for IBM zEnterprise 114 and 196
 252           (2818 and 2817 series). The kernel will be slightly faster but will
 253           not work on older machines.
 254
 255 config MARCH_ZEC12
 256         bool "IBM zBC12 and zEC12"
 257         select HAVE_MARCH_ZEC12_FEATURES
 258         help
 259           Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
 260           2827 series). The kernel will be slightly faster but will not work on
 261           older machines.
 262
 263 config MARCH_Z13
 264         bool "IBM z13s and z13"
 265         select HAVE_MARCH_Z13_FEATURES
 266         help
 267           Select this to enable optimizations for IBM z13s and z13 (2965 and
 268           2964 series). The kernel will be slightly faster but will not work on
 269           older machines.
 270
 271 endchoice
 272
 273 config MARCH_Z900_TUNE
 274         def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
 275
 276 config MARCH_Z990_TUNE
 277         def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
 278
 279 config MARCH_Z9_109_TUNE
 280         def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
 281
 282 config MARCH_Z10_TUNE
 283         def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
 284
 285 config MARCH_Z196_TUNE
 286         def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
 287
 288 config MARCH_ZEC12_TUNE
 289         def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
 290
 291 config MARCH_Z13_TUNE
 292         def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
 293
 294 choice
 295         prompt "Tune code generation"
 296         default TUNE_DEFAULT
 297         help
 298           Cause the compiler to tune (-mtune) the generated code for a machine.
 299           This will make the code run faster on the selected machine but
 300           somewhat slower on other machines.
 301           This option only changes how the compiler emits instructions, not the
 302           selection of instructions itself, so the resulting kernel will run on
 303           all other machines.
 304
 305 config TUNE_DEFAULT
 306         bool "Default"
 307         help
 308           Tune the generated code for the target processor for which the kernel
 309           will be compiled.
 310
 311 config TUNE_Z900
 312         bool "IBM zSeries model z800 and z900"
 313
 314 config TUNE_Z990
 315         bool "IBM zSeries model z890 and z990"
 316
 317 config TUNE_Z9_109
 318         bool "IBM System z9"
 319
 320 config TUNE_Z10
 321         bool "IBM System z10"
 322
 323 config TUNE_Z196
 324         bool "IBM zEnterprise 114 and 196"
 325
 326 config TUNE_ZEC12
 327         bool "IBM zBC12 and zEC12"
 328
 329 config TUNE_Z13
 330         bool "IBM z13"
 331
 332 endchoice
 333
 334 config 64BIT
 335         def_bool y
 336
 337 config COMPAT
 338         def_bool y
 339         prompt "Kernel support for 31 bit emulation"
 340         select COMPAT_BINFMT_ELF if BINFMT_ELF
 341         select ARCH_WANT_OLD_COMPAT_IPC
 342         select COMPAT_OLD_SIGACTION
 343         depends on MULTIUSER
 344         help
 345           Select this option if you want to enable your system kernel to
 346           handle system-calls from ELF binaries for 31 bit ESA.  This option
 347           (and some other stuff like libraries and such) is needed for
 348           executing 31 bit applications.  It is safe to say "Y".
 349
 350 config SYSVIPC_COMPAT
 351         def_bool y if COMPAT && SYSVIPC
 352
 353 config KEYS_COMPAT
 354         def_bool y if COMPAT && KEYS
 355
 356 config SMP
 357         def_bool y
 358         prompt "Symmetric multi-processing support"
 359         ---help---
 360           This enables support for systems with more than one CPU. If you have
 361           a system with only one CPU, like most personal computers, say N. If
 362           you have a system with more than one CPU, say Y.
 363
 364           If you say N here, the kernel will run on uni- and multiprocessor
 365           machines, but will use only one CPU of a multiprocessor machine. If
 366           you say Y here, the kernel will run on many, but not all,
 367           uniprocessor machines. On a uniprocessor machine, the kernel
 368           will run faster if you say N here.
 369
 370           See also the SMP-HOWTO available at
 371           <http://www.tldp.org/docs.html#howto>.
 372
 373           Even if you don't know what to do here, say Y.
 374
 375 config NR_CPUS
 376         int "Maximum number of CPUs (2-512)"
 377         range 2 512
 378         depends on SMP
 379         default "64"
 380         help
 381           This allows you to specify the maximum number of CPUs which this
 382           kernel will support. The maximum supported value is 512 and the
 383           minimum value which makes sense is 2.
 384
 385           This is purely to save memory - each supported CPU adds
 386           approximately sixteen kilobytes to the kernel image.
 387
 388 config HOTPLUG_CPU
 389         def_bool y
 390         prompt "Support for hot-pluggable CPUs"
 391         depends on SMP
 392         help
 393           Say Y here to be able to turn CPUs off and on. CPUs
 394           can be controlled through /sys/devices/system/cpu/cpu#.
 395           Say N if you want to disable CPU hotplug.
 396
 397 # Some NUMA nodes have memory ranges that span
 398 # other nodes.  Even though a pfn is valid and
 399 # between a node's start and end pfns, it may not
 400 # reside on that node.  See memmap_init_zone()
 401 # for details. <- They meant memory holes!
 402 config NODES_SPAN_OTHER_NODES
 403         def_bool NUMA
 404
 405 config NUMA
 406         bool "NUMA support"
 407         depends on SMP && SCHED_TOPOLOGY
 408         default n
 409         help
 410           Enable NUMA support
 411
 412           This option adds NUMA support to the kernel.
 413
 414           An operation mode can be selected by appending
 415           numa=<method> to the kernel command line.
 416
 417           The default behaviour is identical to appending numa=plain to
 418           the command line. This will create just one node with all
 419           available memory and all CPUs in it.
 420
 421 config NODES_SHIFT
 422         int "Maximum NUMA nodes (as a power of 2)"
 423         range 1 10
 424         depends on NUMA
 425         default "4"
 426         help
 427           Specify the maximum number of NUMA nodes available on the target
 428           system. Increases memory reserved to accommodate various tables.
 429
 430 menu "Select NUMA modes"
 431         depends on NUMA
 432
 433 config NUMA_EMU
 434         bool "NUMA emulation"
 435         default y
 436         help
 437           Numa emulation mode will split the available system memory into
 438           equal chunks which then are distributed over the configured number
 439           of nodes in a round-robin manner.
 440
 441           The number of fake nodes is limited by the number of available memory
 442           chunks (i.e. memory size / fake size) and the number of supported
 443           nodes in the kernel.
 444
 445           The CPUs are assigned to the nodes in a way that partially respects
 446           the original machine topology (if supported by the machine).
 447           Fair distribution of the CPUs is not guaranteed.
 448
 449 config EMU_SIZE
 450         hex "NUMA emulation memory chunk size"
 451         default 0x10000000
 452         range 0x400000 0x100000000
 453         depends on NUMA_EMU
 454         help
 455           Select the default size by which the memory is chopped and then
 456           assigned to emulated NUMA nodes.
 457
 458           This can be overridden by specifying
 459
 460           emu_size=<n>
 461
 462           on the kernel command line where also suffixes K, M, G, and T are
 463           supported.
 464
 465 endmenu
 466
 467 config SCHED_SMT
 468         def_bool n
 469
 470 config SCHED_MC
 471         def_bool n
 472
 473 config SCHED_BOOK
 474         def_bool n
 475
 476 config SCHED_TOPOLOGY
 477         def_bool y
 478         prompt "Topology scheduler support"
 479         depends on SMP
 480         select SCHED_SMT
 481         select SCHED_MC
 482         select SCHED_BOOK
 483         help
 484           Topology scheduler support improves the CPU scheduler's decision
 485           making when dealing with machines that have multi-threading,
 486           multiple cores or multiple books.
 487
 488 source kernel/Kconfig.preempt
 489
 490 source kernel/Kconfig.hz
 491
 492 endmenu
 493
 494 menu "Memory setup"
 495
 496 config ARCH_SPARSEMEM_ENABLE
 497         def_bool y
 498         select SPARSEMEM_VMEMMAP_ENABLE
 499         select SPARSEMEM_VMEMMAP
 500
 501 config ARCH_SPARSEMEM_DEFAULT
 502         def_bool y
 503
 504 config ARCH_SELECT_MEMORY_MODEL
 505         def_bool y
 506
 507 config ARCH_ENABLE_MEMORY_HOTPLUG
 508         def_bool y if SPARSEMEM
 509
 510 config ARCH_ENABLE_MEMORY_HOTREMOVE
 511         def_bool y
 512
 513 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 514         def_bool y
 515
 516 config FORCE_MAX_ZONEORDER
 517         int
 518         default "9"
 519
 520 source "mm/Kconfig"
 521
 522 config PACK_STACK
 523         def_bool y
 524         prompt "Pack kernel stack"
 525         help
 526           This option enables the compiler option -mkernel-backchain if it
 527           is available. If the option is available the compiler supports
 528           the new stack layout which dramatically reduces the minimum stack
 529           frame size. With an old compiler a non-leaf function needs a
 530           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 531           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 532           and 24 byte on 64 bit.
 533
 534           Say Y if you are unsure.
 535
 536 config CHECK_STACK
 537         def_bool y
 538         prompt "Detect kernel stack overflow"
 539         help
 540           This option enables the compiler option -mstack-guard and
 541           -mstack-size if they are available. If the compiler supports them
 542           it will emit additional code to each function prolog to trigger
 543           an illegal operation if the kernel stack is about to overflow.
 544
 545           Say N if you are unsure.
 546
 547 config STACK_GUARD
 548         int "Size of the guard area (128-1024)"
 549         range 128 1024
 550         depends on CHECK_STACK
 551         default "256"
 552         help
 553           This allows you to specify the size of the guard area at the lower
 554           end of the kernel stack. If the kernel stack points into the guard
 555           area on function entry an illegal operation is triggered. The size
 556           needs to be a power of 2. Please keep in mind that the size of an
 557           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 558           The minimum size for the stack guard should be 256 for 31 bit and
 559           512 for 64 bit.
 560
 561 config WARN_DYNAMIC_STACK
 562         def_bool n
 563         prompt "Emit compiler warnings for function with dynamic stack usage"
 564         help
 565           This option enables the compiler option -mwarn-dynamicstack. If the
 566           compiler supports this options generates warnings for functions
 567           that dynamically allocate stack space using alloca.
 568
 569           Say N if you are unsure.
 570
 571 endmenu
 572
 573 menu "I/O subsystem"
 574
 575 config QDIO
 576         def_tristate y
 577         prompt "QDIO support"
 578         ---help---
 579           This driver provides the Queued Direct I/O base support for
 580           IBM System z.
 581
 582           To compile this driver as a module, choose M here: the
 583           module will be called qdio.
 584
 585           If unsure, say Y.
 586
 587 menuconfig PCI
 588         bool "PCI support"
 589         select PCI_MSI
 590         select IOMMU_SUPPORT
 591         help
 592           Enable PCI support.
 593
 594 if PCI
 595
 596 config PCI_NR_FUNCTIONS
 597         int "Maximum number of PCI functions (1-4096)"
 598         range 1 4096
 599         default "64"
 600         help
 601           This allows you to specify the maximum number of PCI functions which
 602           this kernel will support.
 603
 604 config PCI_NR_MSI
 605         int "Maximum number of MSI interrupts (64-32768)"
 606         range 64 32768
 607         default "256"
 608         help
 609           This defines the number of virtual interrupts the kernel will
 610           provide for MSI interrupts. If you configure your system to have
 611           too few drivers will fail to allocate MSI interrupts for all
 612           PCI devices.
 613
 614 source "drivers/pci/Kconfig"
 615
 616 endif   # PCI
 617
 618 config PCI_DOMAINS
 619         def_bool PCI
 620
 621 config HAS_IOMEM
 622         def_bool PCI
 623
 624 config IOMMU_HELPER
 625         def_bool PCI
 626
 627 config NEED_SG_DMA_LENGTH
 628         def_bool PCI
 629
 630 config NEED_DMA_MAP_STATE
 631         def_bool PCI
 632
 633 config CHSC_SCH
 634         def_tristate m
 635         prompt "Support for CHSC subchannels"
 636         help
 637           This driver allows usage of CHSC subchannels. A CHSC subchannel
 638           is usually present on LPAR only.
 639           The driver creates a device /dev/chsc, which may be used to
 640           obtain I/O configuration information about the machine and
 641           to issue asynchronous chsc commands (DANGEROUS).
 642           You will usually only want to use this interface on a special
 643           LPAR designated for system management.
 644
 645           To compile this driver as a module, choose M here: the
 646           module will be called chsc_sch.
 647
 648           If unsure, say N.
 649
 650 config SCM_BUS
 651         def_bool y
 652         prompt "SCM bus driver"
 653         help
 654           Bus driver for Storage Class Memory.
 655
 656 config EADM_SCH
 657         def_tristate m
 658         prompt "Support for EADM subchannels"
 659         depends on SCM_BUS
 660         help
 661           This driver allows usage of EADM subchannels. EADM subchannels act
 662           as a communication vehicle for SCM increments.
 663
 664           To compile this driver as a module, choose M here: the
 665           module will be called eadm_sch.
 666
 667 endmenu
 668
 669 menu "Dump support"
 670
 671 config CRASH_DUMP
 672         bool "kernel crash dumps"
 673         depends on SMP
 674         select KEXEC
 675         help
 676           Generate crash dump after being started by kexec.
 677           Crash dump kernels are loaded in the main kernel with kexec-tools
 678           into a specially reserved region and then later executed after
 679           a crash by kdump/kexec.
 680           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 681           This option also enables s390 zfcpdump.
 682           See also <file:Documentation/s390/zfcpdump.txt>
 683
 684 endmenu
 685
 686 menu "Executable file formats / Emulations"
 687
 688 source "fs/Kconfig.binfmt"
 689
 690 config SECCOMP
 691         def_bool y
 692         prompt "Enable seccomp to safely compute untrusted bytecode"
 693         depends on PROC_FS
 694         help
 695           This kernel feature is useful for number crunching applications
 696           that may need to compute untrusted bytecode during their
 697           execution. By using pipes or other transports made available to
 698           the process as file descriptors supporting the read/write
 699           syscalls, it's possible to isolate those applications in
 700           their own address space using seccomp. Once seccomp is
 701           enabled via /proc/<pid>/seccomp, it cannot be disabled
 702           and the task is only allowed to execute a few safe syscalls
 703           defined by each seccomp mode.
 704
 705           If unsure, say Y.
 706
 707 endmenu
 708
 709 menu "Power Management"
 710
 711 config ARCH_HIBERNATION_POSSIBLE
 712         def_bool y
 713
 714 source "kernel/power/Kconfig"
 715
 716 endmenu
 717
 718 source "net/Kconfig"
 719
 720 config PCMCIA
 721         def_bool n
 722
 723 config CCW
 724         def_bool y
 725
 726 source "drivers/Kconfig"
 727
 728 source "fs/Kconfig"
 729
 730 source "arch/s390/Kconfig.debug"
 731
 732 source "security/Kconfig"
 733
 734 source "crypto/Kconfig"
 735
 736 source "lib/Kconfig"
 737
 738 menu "Virtualization"
 739
 740 config PFAULT
 741         def_bool y
 742         prompt "Pseudo page fault support"
 743         help
 744           Select this option, if you want to use PFAULT pseudo page fault
 745           handling under VM. If running native or in LPAR, this option
 746           has no effect. If your VM does not support PFAULT, PAGEEX
 747           pseudo page fault handling will be used.
 748           Note that VM 4.2 supports PFAULT but has a bug in its
 749           implementation that causes some problems.
 750           Everybody who wants to run Linux under VM != VM4.2 should select
 751           this option.
 752
 753 config SHARED_KERNEL
 754         bool "VM shared kernel support"
 755         depends on !JUMP_LABEL
 756         help
 757           Select this option, if you want to share the text segment of the
 758           Linux kernel between different VM guests. This reduces memory
 759           usage with lots of guests but greatly increases kernel size.
 760           Also if a kernel was IPL'ed from a shared segment the kexec system
 761           call will not work.
 762           You should only select this option if you know what you are
 763           doing and want to exploit this feature.
 764
 765 config CMM
 766         def_tristate n
 767         prompt "Cooperative memory management"
 768         help
 769           Select this option, if you want to enable the kernel interface
 770           to reduce the memory size of the system. This is accomplished
 771           by allocating pages of memory and put them "on hold". This only
 772           makes sense for a system running under VM where the unused pages
 773           will be reused by VM for other guest systems. The interface
 774           allows an external monitor to balance memory of many systems.
 775           Everybody who wants to run Linux under VM should select this
 776           option.
 777
 778 config CMM_IUCV
 779         def_bool y
 780         prompt "IUCV special message interface to cooperative memory management"
 781         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 782         help
 783           Select this option to enable the special message interface to
 784           the cooperative memory management.
 785
 786 config APPLDATA_BASE
 787         def_bool n
 788         prompt "Linux - VM Monitor Stream, base infrastructure"
 789         depends on PROC_FS
 790         help
 791           This provides a kernel interface for creating and updating z/VM APPLDATA
 792           monitor records. The monitor records are updated at certain time
 793           intervals, once the timer is started.
 794           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 795           i.e. enables or disables monitoring on the Linux side.
 796           A custom interval value (in seconds) can be written to
 797           /proc/appldata/interval.
 798
 799           Defaults are 60 seconds interval and timer off.
 800           The /proc entries can also be read from, showing the current settings.
 801
 802 config APPLDATA_MEM
 803         def_tristate m
 804         prompt "Monitor memory management statistics"
 805         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 806         help
 807           This provides memory management related data to the Linux - VM Monitor
 808           Stream, like paging/swapping rate, memory utilisation, etc.
 809           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 810           APPLDATA monitor record, i.e. enables or disables monitoring this record
 811           on the z/VM side.
 812
 813           Default is disabled.
 814           The /proc entry can also be read from, showing the current settings.
 815
 816           This can also be compiled as a module, which will be called
 817           appldata_mem.o.
 818
 819 config APPLDATA_OS
 820         def_tristate m
 821         prompt "Monitor OS statistics"
 822         depends on APPLDATA_BASE
 823         help
 824           This provides OS related data to the Linux - VM Monitor Stream, like
 825           CPU utilisation, etc.
 826           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 827           APPLDATA monitor record, i.e. enables or disables monitoring this record
 828           on the z/VM side.
 829
 830           Default is disabled.
 831           This can also be compiled as a module, which will be called
 832           appldata_os.o.
 833
 834 config APPLDATA_NET_SUM
 835         def_tristate m
 836         prompt "Monitor overall network statistics"
 837         depends on APPLDATA_BASE && NET
 838         help
 839           This provides network related data to the Linux - VM Monitor Stream,
 840           currently there is only a total sum of network I/O statistics, no
 841           per-interface data.
 842           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 843           APPLDATA monitor record, i.e. enables or disables monitoring this record
 844           on the z/VM side.
 845
 846           Default is disabled.
 847           This can also be compiled as a module, which will be called
 848           appldata_net_sum.o.
 849
 850 config S390_HYPFS_FS
 851         def_bool y
 852         prompt "s390 hypervisor file system support"
 853         select SYS_HYPERVISOR
 854         help
 855           This is a virtual file system intended to provide accounting
 856           information in an s390 hypervisor environment.
 857
 858 source "arch/s390/kvm/Kconfig"
 859
 860 config S390_GUEST
 861         def_bool y
 862         prompt "s390 support for virtio devices"
 863         select TTY
 864         select VIRTUALIZATION
 865         select VIRTIO
 866         select VIRTIO_CONSOLE
 867         help
 868           Enabling this option adds support for virtio based paravirtual device
 869           drivers on s390.
 870
 871           Select this option if you want to run the kernel as a guest under
 872           the KVM hypervisor.
 873
 874 endmenu