arch/s390/Kconfig

   1 #
   2 # For a description of the syntax of this configuration file,
   3 # see Documentation/kbuild/kconfig-language.txt.
   4 #
   5
   6 config SCHED_MC
   7         def_bool y
   8         depends on SMP
   9
  10 config MMU
  11         def_bool y
  12
  13 config ZONE_DMA
  14         def_bool y
  15         depends on 64BIT
  16
  17 config LOCKDEP_SUPPORT
  18         def_bool y
  19
  20 config STACKTRACE_SUPPORT
  21         def_bool y
  22
  23 config HAVE_LATENCYTOP_SUPPORT
  24         def_bool y
  25
  26 config RWSEM_GENERIC_SPINLOCK
  27         bool
  28
  29 config RWSEM_XCHGADD_ALGORITHM
  30         def_bool y
  31
  32 config ARCH_HAS_ILOG2_U32
  33         bool
  34         default n
  35
  36 config ARCH_HAS_ILOG2_U64
  37         bool
  38         default n
  39
  40 config GENERIC_HWEIGHT
  41         def_bool y
  42
  43 config GENERIC_TIME
  44         def_bool y
  45
  46 config GENERIC_TIME_VSYSCALL
  47         def_bool y
  48
  49 config GENERIC_CLOCKEVENTS
  50         def_bool y
  51
  52 config GENERIC_BUG
  53         bool
  54         depends on BUG
  55         default y
  56
  57 config NO_IOMEM
  58         def_bool y
  59
  60 config NO_DMA
  61         def_bool y
  62
  63 config GENERIC_LOCKBREAK
  64         bool
  65         default y
  66         depends on SMP && PREEMPT
  67
  68 config PGSTE
  69         bool
  70         default y if KVM
  71
  72 config VIRT_CPU_ACCOUNTING
  73         def_bool y
  74
  75 mainmenu "Linux Kernel Configuration"
  76
  77 config S390
  78         def_bool y
  79         select USE_GENERIC_SMP_HELPERS if SMP
  80         select HAVE_FUNCTION_TRACER
  81         select HAVE_OPROFILE
  82         select HAVE_KPROBES
  83         select HAVE_KRETPROBES
  84         select HAVE_KVM if 64BIT
  85         select HAVE_ARCH_TRACEHOOK
  86         select INIT_ALL_POSSIBLE
  87
  88 source "init/Kconfig"
  89
  90 source "kernel/Kconfig.freezer"
  91
  92 menu "Base setup"
  93
  94 comment "Processor type and features"
  95
  96 source "kernel/time/Kconfig"
  97
  98 config 64BIT
  99         bool "64 bit kernel"
 100         help
 101           Select this option if you have a 64 bit IBM zSeries machine
 102           and want to use the 64 bit addressing mode.
 103
 104 config 32BIT
 105         bool
 106         default y if !64BIT
 107
 108 config SMP
 109         bool "Symmetric multi-processing support"
 110         ---help---
 111           This enables support for systems with more than one CPU. If you have
 112           a system with only one CPU, like most personal computers, say N. If
 113           you have a system with more than one CPU, say Y.
 114
 115           If you say N here, the kernel will run on single and multiprocessor
 116           machines, but will use only one CPU of a multiprocessor machine. If
 117           you say Y here, the kernel will run on many, but not all,
 118           singleprocessor machines. On a singleprocessor machine, the kernel
 119           will run faster if you say N here.
 120
 121           See also the SMP-HOWTO available at
 122           <http://www.tldp.org/docs.html#howto>.
 123
 124           Even if you don't know what to do here, say Y.
 125
 126 config NR_CPUS
 127         int "Maximum number of CPUs (2-64)"
 128         range 2 64
 129         depends on SMP
 130         default "32" if !64BIT
 131         default "64" if 64BIT
 132         help
 133           This allows you to specify the maximum number of CPUs which this
 134           kernel will support.  The maximum supported value is 64 and the
 135           minimum value which makes sense is 2.
 136
 137           This is purely to save memory - each supported CPU adds
 138           approximately sixteen kilobytes to the kernel image.
 139
 140 config HOTPLUG_CPU
 141         bool "Support for hot-pluggable CPUs"
 142         depends on SMP
 143         select HOTPLUG
 144         default n
 145         help
 146           Say Y here to be able to turn CPUs off and on. CPUs
 147           can be controlled through /sys/devices/system/cpu/cpu#.
 148           Say N if you want to disable CPU hotplug.
 149
 150 config MATHEMU
 151         bool "IEEE FPU emulation"
 152         depends on MARCH_G5
 153         help
 154           This option is required for IEEE compliant floating point arithmetic
 155           on older S/390 machines. Say Y unless you know your machine doesn't
 156           need this.
 157
 158 config COMPAT
 159         bool "Kernel support for 31 bit emulation"
 160         depends on 64BIT
 161         select COMPAT_BINFMT_ELF
 162         help
 163           Select this option if you want to enable your system kernel to
 164           handle system-calls from ELF binaries for 31 bit ESA.  This option
 165           (and some other stuff like libraries and such) is needed for
 166           executing 31 bit applications.  It is safe to say "Y".
 167
 168 config SYSVIPC_COMPAT
 169         bool
 170         depends on COMPAT && SYSVIPC
 171         default y
 172
 173 config AUDIT_ARCH
 174         bool
 175         default y
 176
 177 config S390_SWITCH_AMODE
 178         bool "Switch kernel/user addressing modes"
 179         help
 180           This option allows to switch the addressing modes of kernel and user
 181           space. The kernel parameter switch_amode=on will enable this feature,
 182           default is disabled. Enabling this (via kernel parameter) on machines
 183           earlier than IBM System z9-109 EC/BC will reduce system performance.
 184
 185           Note that this option will also be selected by selecting the execute
 186           protection option below. Enabling the execute protection via the
 187           noexec kernel parameter will also switch the addressing modes,
 188           independent of the switch_amode kernel parameter.
 189
 190
 191 config S390_EXEC_PROTECT
 192         bool "Data execute protection"
 193         select S390_SWITCH_AMODE
 194         help
 195           This option allows to enable a buffer overflow protection for user
 196           space programs and it also selects the addressing mode option above.
 197           The kernel parameter noexec=on will enable this feature and also
 198           switch the addressing modes, default is disabled. Enabling this (via
 199           kernel parameter) on machines earlier than IBM System z9-109 EC/BC
 200           will reduce system performance.
 201
 202 comment "Code generation options"
 203
 204 choice
 205         prompt "Processor type"
 206         default MARCH_G5
 207
 208 config MARCH_G5
 209         bool "S/390 model G5 and G6"
 210         depends on !64BIT
 211         help
 212           Select this to build a 31 bit kernel that works
 213           on all S/390 and zSeries machines.
 214
 215 config MARCH_Z900
 216         bool "IBM eServer zSeries model z800 and z900"
 217         help
 218           Select this to optimize for zSeries machines. This
 219           will enable some optimizations that are not available
 220           on older 31 bit only CPUs.
 221
 222 config MARCH_Z990
 223         bool "IBM eServer zSeries model z890 and z990"
 224         help
 225           Select this enable optimizations for model z890/z990.
 226           This will be slightly faster but does not work on
 227           older machines such as the z900.
 228
 229 config MARCH_Z9_109
 230         bool "IBM System z9"
 231         help
 232           Select this to enable optimizations for IBM System z9-109, IBM
 233           System z9 Enterprise Class (z9 EC), and IBM System z9 Business
 234           Class (z9 BC). The kernel will be slightly faster but will not
 235           work on older machines such as the z990, z890, z900, and z800.
 236
 237 config MARCH_Z10
 238         bool "IBM System z10"
 239         help
 240           Select this to enable optimizations for IBM System z10. The
 241           kernel will be slightly faster but will not work on older
 242           machines such as the z990, z890, z900, z800, z9-109, z9-ec
 243           and z9-bc.
 244
 245 endchoice
 246
 247 config PACK_STACK
 248         bool "Pack kernel stack"
 249         help
 250           This option enables the compiler option -mkernel-backchain if it
 251           is available. If the option is available the compiler supports
 252           the new stack layout which dramatically reduces the minimum stack
 253           frame size. With an old compiler a non-leaf function needs a
 254           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 255           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 256           and 24 byte on 64 bit.
 257
 258           Say Y if you are unsure.
 259
 260 config SMALL_STACK
 261         bool "Use 8kb for kernel stack instead of 16kb"
 262         depends on PACK_STACK && 64BIT && !LOCKDEP
 263         help
 264           If you say Y here and the compiler supports the -mkernel-backchain
 265           option the kernel will use a smaller kernel stack size. The reduced
 266           size is 8kb instead of 16kb. This allows to run more threads on a
 267           system and reduces the pressure on the memory management for higher
 268           order page allocations.
 269
 270           Say N if you are unsure.
 271
 272 config CHECK_STACK
 273         bool "Detect kernel stack overflow"
 274         help
 275           This option enables the compiler option -mstack-guard and
 276           -mstack-size if they are available. If the compiler supports them
 277           it will emit additional code to each function prolog to trigger
 278           an illegal operation if the kernel stack is about to overflow.
 279
 280           Say N if you are unsure.
 281
 282 config STACK_GUARD
 283         int "Size of the guard area (128-1024)"
 284         range 128 1024
 285         depends on CHECK_STACK
 286         default "256"
 287         help
 288           This allows you to specify the size of the guard area at the lower
 289           end of the kernel stack. If the kernel stack points into the guard
 290           area on function entry an illegal operation is triggered. The size
 291           needs to be a power of 2. Please keep in mind that the size of an
 292           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 293           The minimum size for the stack guard should be 256 for 31 bit and
 294           512 for 64 bit.
 295
 296 config WARN_STACK
 297         bool "Emit compiler warnings for function with broken stack usage"
 298         help
 299           This option enables the compiler options -mwarn-framesize and
 300           -mwarn-dynamicstack. If the compiler supports these options it
 301           will generate warnings for function which either use alloca or
 302           create a stack frame bigger than CONFIG_WARN_STACK_SIZE.
 303
 304           Say N if you are unsure.
 305
 306 config WARN_STACK_SIZE
 307         int "Maximum frame size considered safe (128-2048)"
 308         range 128 2048
 309         depends on WARN_STACK
 310         default "2048"
 311         help
 312           This allows you to specify the maximum frame size a function may
 313           have without the compiler complaining about it.
 314
 315 config ARCH_POPULATES_NODE_MAP
 316         def_bool y
 317
 318 comment "Kernel preemption"
 319
 320 source "kernel/Kconfig.preempt"
 321
 322 config ARCH_SPARSEMEM_ENABLE
 323         def_bool y
 324         select SPARSEMEM_VMEMMAP_ENABLE
 325         select SPARSEMEM_VMEMMAP
 326         select SPARSEMEM_STATIC if !64BIT
 327
 328 config ARCH_SPARSEMEM_DEFAULT
 329         def_bool y
 330
 331 config ARCH_SELECT_MEMORY_MODEL
 332        def_bool y
 333
 334 config ARCH_ENABLE_MEMORY_HOTPLUG
 335         def_bool y
 336         depends on SPARSEMEM
 337
 338 config ARCH_ENABLE_MEMORY_HOTREMOVE
 339         def_bool y
 340
 341 source "mm/Kconfig"
 342
 343 comment "I/O subsystem configuration"
 344
 345 config MACHCHK_WARNING
 346         bool "Process warning machine checks"
 347         help
 348           Select this option if you want the machine check handler on IBM S/390 or
 349           zSeries to process warning machine checks (e.g. on power failures).
 350           If unsure, say "Y".
 351
 352 config QDIO
 353         tristate "QDIO support"
 354         ---help---
 355           This driver provides the Queued Direct I/O base support for
 356           IBM System z.
 357
 358           To compile this driver as a module, choose M here: the
 359           module will be called qdio.
 360
 361           If unsure, say Y.
 362
 363 config CHSC_SCH
 364         tristate "Support for CHSC subchannels"
 365         help
 366           This driver allows usage of CHSC subchannels. A CHSC subchannel
 367           is usually present on LPAR only.
 368           The driver creates a device /dev/chsc, which may be used to
 369           obtain I/O configuration information about the machine and
 370           to issue asynchronous chsc commands (DANGEROUS).
 371           You will usually only want to use this interface on a special
 372           LPAR designated for system management.
 373
 374           To compile this driver as a module, choose M here: the
 375           module will be called chsc_sch.
 376
 377           If unsure, say N.
 378
 379 comment "Misc"
 380
 381 config IPL
 382         bool "Builtin IPL record support"
 383         help
 384           If you want to use the produced kernel to IPL directly from a
 385           device, you have to merge a bootsector specific to the device
 386           into the first bytes of the kernel. You will have to select the
 387           IPL device.
 388
 389 choice
 390         prompt "IPL method generated into head.S"
 391         depends on IPL
 392         default IPL_VM
 393         help
 394           Select "tape" if you want to IPL the image from a Tape.
 395
 396           Select "vm_reader" if you are running under VM/ESA and want
 397           to IPL the image from the emulated card reader.
 398
 399 config IPL_TAPE
 400         bool "tape"
 401
 402 config IPL_VM
 403         bool "vm_reader"
 404
 405 endchoice
 406
 407 source "fs/Kconfig.binfmt"
 408
 409 config FORCE_MAX_ZONEORDER
 410         int
 411         default "9"
 412
 413 config PROCESS_DEBUG
 414         bool "Show crashed user process info"
 415         help
 416           Say Y to print all process fault locations to the console.  This is
 417           a debugging option; you probably do not want to set it unless you
 418           are an S390 port maintainer.
 419
 420 config PFAULT
 421         bool "Pseudo page fault support"
 422         help
 423           Select this option, if you want to use PFAULT pseudo page fault
 424           handling under VM. If running native or in LPAR, this option
 425           has no effect. If your VM does not support PFAULT, PAGEEX
 426           pseudo page fault handling will be used.
 427           Note that VM 4.2 supports PFAULT but has a bug in its
 428           implementation that causes some problems.
 429           Everybody who wants to run Linux under VM != VM4.2 should select
 430           this option.
 431
 432 config SHARED_KERNEL
 433         bool "VM shared kernel support"
 434         help
 435           Select this option, if you want to share the text segment of the
 436           Linux kernel between different VM guests. This reduces memory
 437           usage with lots of guests but greatly increases kernel size.
 438           Also if a kernel was IPL'ed from a shared segment the kexec system
 439           call will not work.
 440           You should only select this option if you know what you are
 441           doing and want to exploit this feature.
 442
 443 config CMM
 444         tristate "Cooperative memory management"
 445         help
 446           Select this option, if you want to enable the kernel interface
 447           to reduce the memory size of the system. This is accomplished
 448           by allocating pages of memory and put them "on hold". This only
 449           makes sense for a system running under VM where the unused pages
 450           will be reused by VM for other guest systems. The interface
 451           allows an external monitor to balance memory of many systems.
 452           Everybody who wants to run Linux under VM should select this
 453           option.
 454
 455 config CMM_PROC
 456         bool "/proc interface to cooperative memory management"
 457         depends on CMM
 458         help
 459           Select this option to enable the /proc interface to the
 460           cooperative memory management.
 461
 462 config CMM_IUCV
 463         bool "IUCV special message interface to cooperative memory management"
 464         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 465         help
 466           Select this option to enable the special message interface to
 467           the cooperative memory management.
 468
 469 config PAGE_STATES
 470         bool "Unused page notification"
 471         help
 472           This enables the notification of unused pages to the
 473           hypervisor. The ESSA instruction is used to do the states
 474           changes between a page that has content and the unused state.
 475
 476 config APPLDATA_BASE
 477         bool "Linux - VM Monitor Stream, base infrastructure"
 478         depends on PROC_FS
 479         help
 480           This provides a kernel interface for creating and updating z/VM APPLDATA
 481           monitor records. The monitor records are updated at certain time
 482           intervals, once the timer is started.
 483           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 484           i.e. enables or disables monitoring on the Linux side.
 485           A custom interval value (in seconds) can be written to
 486           /proc/appldata/interval.
 487
 488           Defaults are 60 seconds interval and timer off.
 489           The /proc entries can also be read from, showing the current settings.
 490
 491 config APPLDATA_MEM
 492         tristate "Monitor memory management statistics"
 493         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 494         help
 495           This provides memory management related data to the Linux - VM Monitor
 496           Stream, like paging/swapping rate, memory utilisation, etc.
 497           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 498           APPLDATA monitor record, i.e. enables or disables monitoring this record
 499           on the z/VM side.
 500
 501           Default is disabled.
 502           The /proc entry can also be read from, showing the current settings.
 503
 504           This can also be compiled as a module, which will be called
 505           appldata_mem.o.
 506
 507 config APPLDATA_OS
 508         tristate "Monitor OS statistics"
 509         depends on APPLDATA_BASE
 510         help
 511           This provides OS related data to the Linux - VM Monitor Stream, like
 512           CPU utilisation, etc.
 513           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 514           APPLDATA monitor record, i.e. enables or disables monitoring this record
 515           on the z/VM side.
 516
 517           Default is disabled.
 518           This can also be compiled as a module, which will be called
 519           appldata_os.o.
 520
 521 config APPLDATA_NET_SUM
 522         tristate "Monitor overall network statistics"
 523         depends on APPLDATA_BASE
 524         help
 525           This provides network related data to the Linux - VM Monitor Stream,
 526           currently there is only a total sum of network I/O statistics, no
 527           per-interface data.
 528           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 529           APPLDATA monitor record, i.e. enables or disables monitoring this record
 530           on the z/VM side.
 531
 532           Default is disabled.
 533           This can also be compiled as a module, which will be called
 534           appldata_net_sum.o.
 535
 536 source kernel/Kconfig.hz
 537
 538 config S390_HYPFS_FS
 539         bool "s390 hypervisor file system support"
 540         select SYS_HYPERVISOR
 541         default y
 542         help
 543           This is a virtual file system intended to provide accounting
 544           information in an s390 hypervisor environment.
 545
 546 config KEXEC
 547         bool "kexec system call"
 548         help
 549           kexec is a system call that implements the ability to shutdown your
 550           current kernel, and to start another kernel.  It is like a reboot
 551           but is independent of hardware/microcode support.
 552
 553 config ZFCPDUMP
 554         tristate "zfcpdump support"
 555         select SMP
 556         default n
 557         help
 558           Select this option if you want to build an zfcpdump enabled kernel.
 559           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 560
 561 config S390_GUEST
 562 bool "s390 guest support for KVM (EXPERIMENTAL)"
 563         depends on 64BIT && EXPERIMENTAL
 564         select VIRTIO
 565         select VIRTIO_RING
 566         select VIRTIO_CONSOLE
 567         help
 568           Select this option if you want to run the kernel as a guest under
 569           the KVM hypervisor. This will add detection for KVM as well  as a
 570           virtio transport. If KVM is detected, the virtio console will be
 571           the default console.
 572 endmenu
 573
 574 source "net/Kconfig"
 575
 576 config PCMCIA
 577         def_bool n
 578
 579 config CCW
 580         def_bool y
 581
 582 source "drivers/Kconfig"
 583
 584 source "fs/Kconfig"
 585
 586 source "arch/s390/Kconfig.debug"
 587
 588 source "security/Kconfig"
 589
 590 source "crypto/Kconfig"
 591
 592 source "lib/Kconfig"
 593
 594 source "arch/s390/kvm/Kconfig"