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_CLOCKEVENTS
  47         def_bool y
  48
  49 config GENERIC_BUG
  50         bool
  51         depends on BUG
  52         default y
  53
  54 config NO_IOMEM
  55         def_bool y
  56
  57 config NO_DMA
  58         def_bool y
  59
  60 config GENERIC_LOCKBREAK
  61         bool
  62         default y
  63         depends on SMP && PREEMPT
  64
  65 mainmenu "Linux Kernel Configuration"
  66
  67 config S390
  68         def_bool y
  69         select HAVE_OPROFILE
  70         select HAVE_KPROBES
  71         select HAVE_KRETPROBES
  72
  73 source "init/Kconfig"
  74
  75 menu "Base setup"
  76
  77 comment "Processor type and features"
  78
  79 source "kernel/time/Kconfig"
  80
  81 config 64BIT
  82         bool "64 bit kernel"
  83         help
  84           Select this option if you have a 64 bit IBM zSeries machine
  85           and want to use the 64 bit addressing mode.
  86
  87 config 32BIT
  88         bool
  89         default y if !64BIT
  90
  91 config SMP
  92         bool "Symmetric multi-processing support"
  93         ---help---
  94           This enables support for systems with more than one CPU. If you have
  95           a system with only one CPU, like most personal computers, say N. If
  96           you have a system with more than one CPU, say Y.
  97
  98           If you say N here, the kernel will run on single and multiprocessor
  99           machines, but will use only one CPU of a multiprocessor machine. If
 100           you say Y here, the kernel will run on many, but not all,
 101           singleprocessor machines. On a singleprocessor machine, the kernel
 102           will run faster if you say N here.
 103
 104           See also the SMP-HOWTO available at
 105           <http://www.tldp.org/docs.html#howto>.
 106
 107           Even if you don't know what to do here, say Y.
 108
 109 config NR_CPUS
 110         int "Maximum number of CPUs (2-64)"
 111         range 2 64
 112         depends on SMP
 113         default "32" if !64BIT
 114         default "64" if 64BIT
 115         help
 116           This allows you to specify the maximum number of CPUs which this
 117           kernel will support.  The maximum supported value is 64 and the
 118           minimum value which makes sense is 2.
 119
 120           This is purely to save memory - each supported CPU adds
 121           approximately sixteen kilobytes to the kernel image.
 122
 123 config HOTPLUG_CPU
 124         bool "Support for hot-pluggable CPUs"
 125         depends on SMP
 126         select HOTPLUG
 127         default n
 128         help
 129           Say Y here to be able to turn CPUs off and on. CPUs
 130           can be controlled through /sys/devices/system/cpu/cpu#.
 131           Say N if you want to disable CPU hotplug.
 132
 133 config MATHEMU
 134         bool "IEEE FPU emulation"
 135         depends on MARCH_G5
 136         help
 137           This option is required for IEEE compliant floating point arithmetic
 138           on older S/390 machines. Say Y unless you know your machine doesn't
 139           need this.
 140
 141 config COMPAT
 142         bool "Kernel support for 31 bit emulation"
 143         depends on 64BIT
 144         help
 145           Select this option if you want to enable your system kernel to
 146           handle system-calls from ELF binaries for 31 bit ESA.  This option
 147           (and some other stuff like libraries and such) is needed for
 148           executing 31 bit applications.  It is safe to say "Y".
 149
 150 config SYSVIPC_COMPAT
 151         bool
 152         depends on COMPAT && SYSVIPC
 153         default y
 154
 155 config AUDIT_ARCH
 156         bool
 157         default y
 158
 159 config S390_SWITCH_AMODE
 160         bool "Switch kernel/user addressing modes"
 161         help
 162           This option allows to switch the addressing modes of kernel and user
 163           space. The kernel parameter switch_amode=on will enable this feature,
 164           default is disabled. Enabling this (via kernel parameter) on machines
 165           earlier than IBM System z9-109 EC/BC will reduce system performance.
 166
 167           Note that this option will also be selected by selecting the execute
 168           protection option below. Enabling the execute protection via the
 169           noexec kernel parameter will also switch the addressing modes,
 170           independent of the switch_amode kernel parameter.
 171
 172
 173 config S390_EXEC_PROTECT
 174         bool "Data execute protection"
 175         select S390_SWITCH_AMODE
 176         help
 177           This option allows to enable a buffer overflow protection for user
 178           space programs and it also selects the addressing mode option above.
 179           The kernel parameter noexec=on will enable this feature and also
 180           switch the addressing modes, default is disabled. Enabling this (via
 181           kernel parameter) on machines earlier than IBM System z9-109 EC/BC
 182           will reduce system performance.
 183
 184 comment "Code generation options"
 185
 186 choice
 187         prompt "Processor type"
 188         default MARCH_G5
 189
 190 config MARCH_G5
 191         bool "S/390 model G5 and G6"
 192         depends on !64BIT
 193         help
 194           Select this to build a 31 bit kernel that works
 195           on all S/390 and zSeries machines.
 196
 197 config MARCH_Z900
 198         bool "IBM eServer zSeries model z800 and z900"
 199         help
 200           Select this to optimize for zSeries machines. This
 201           will enable some optimizations that are not available
 202           on older 31 bit only CPUs.
 203
 204 config MARCH_Z990
 205         bool "IBM eServer zSeries model z890 and z990"
 206         help
 207           Select this enable optimizations for model z890/z990.
 208           This will be slightly faster but does not work on
 209           older machines such as the z900.
 210
 211 config MARCH_Z9_109
 212         bool "IBM System z9"
 213         help
 214           Select this to enable optimizations for IBM System z9-109, IBM
 215           System z9 Enterprise Class (z9 EC), and IBM System z9 Business
 216           Class (z9 BC). The kernel will be slightly faster but will not
 217           work on older machines such as the z990, z890, z900, and z800.
 218
 219 endchoice
 220
 221 config PACK_STACK
 222         bool "Pack kernel stack"
 223         help
 224           This option enables the compiler option -mkernel-backchain if it
 225           is available. If the option is available the compiler supports
 226           the new stack layout which dramatically reduces the minimum stack
 227           frame size. With an old compiler a non-leaf function needs a
 228           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 229           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 230           and 24 byte on 64 bit.
 231
 232           Say Y if you are unsure.
 233
 234 config SMALL_STACK
 235         bool "Use 4kb/8kb for kernel stack instead of 8kb/16kb"
 236         depends on PACK_STACK && !LOCKDEP
 237         help
 238           If you say Y here and the compiler supports the -mkernel-backchain
 239           option the kernel will use a smaller kernel stack size. For 31 bit
 240           the reduced size is 4kb instead of 8kb and for 64 bit it is 8kb
 241           instead of 16kb. This allows to run more thread on a system and
 242           reduces the pressure on the memory management for higher order
 243           page allocations.
 244
 245           Say N if you are unsure.
 246
 247
 248 config CHECK_STACK
 249         bool "Detect kernel stack overflow"
 250         help
 251           This option enables the compiler option -mstack-guard and
 252           -mstack-size if they are available. If the compiler supports them
 253           it will emit additional code to each function prolog to trigger
 254           an illegal operation if the kernel stack is about to overflow.
 255
 256           Say N if you are unsure.
 257
 258 config STACK_GUARD
 259         int "Size of the guard area (128-1024)"
 260         range 128 1024
 261         depends on CHECK_STACK
 262         default "256"
 263         help
 264           This allows you to specify the size of the guard area at the lower
 265           end of the kernel stack. If the kernel stack points into the guard
 266           area on function entry an illegal operation is triggered. The size
 267           needs to be a power of 2. Please keep in mind that the size of an
 268           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 269           The minimum size for the stack guard should be 256 for 31 bit and
 270           512 for 64 bit.
 271
 272 config WARN_STACK
 273         bool "Emit compiler warnings for function with broken stack usage"
 274         help
 275           This option enables the compiler options -mwarn-framesize and
 276           -mwarn-dynamicstack. If the compiler supports these options it
 277           will generate warnings for function which either use alloca or
 278           create a stack frame bigger then CONFIG_WARN_STACK_SIZE.
 279
 280           Say N if you are unsure.
 281
 282 config WARN_STACK_SIZE
 283         int "Maximum frame size considered safe (128-2048)"
 284         range 128 2048
 285         depends on WARN_STACK
 286         default "256"
 287         help
 288           This allows you to specify the maximum frame size a function may
 289           have without the compiler complaining about it.
 290
 291 config ARCH_POPULATES_NODE_MAP
 292         def_bool y
 293
 294 comment "Kernel preemption"
 295
 296 source "kernel/Kconfig.preempt"
 297
 298 source "mm/Kconfig"
 299
 300 comment "I/O subsystem configuration"
 301
 302 config MACHCHK_WARNING
 303         bool "Process warning machine checks"
 304         help
 305           Select this option if you want the machine check handler on IBM S/390 or
 306           zSeries to process warning machine checks (e.g. on power failures).
 307           If unsure, say "Y".
 308
 309 config QDIO
 310         tristate "QDIO support"
 311         ---help---
 312           This driver provides the Queued Direct I/O base support for
 313           IBM System z.
 314
 315           To compile this driver as a module, choose M here: the
 316           module will be called qdio.
 317
 318           If unsure, say Y.
 319
 320 config QDIO_DEBUG
 321         bool "Extended debugging information"
 322         depends on QDIO
 323         help
 324           Say Y here to get extended debugging output in
 325             /sys/kernel/debug/s390dbf/qdio...
 326           Warning: this option reduces the performance of the QDIO module.
 327
 328           If unsure, say N.
 329
 330 comment "Misc"
 331
 332 config IPL
 333         bool "Builtin IPL record support"
 334         help
 335           If you want to use the produced kernel to IPL directly from a
 336           device, you have to merge a bootsector specific to the device
 337           into the first bytes of the kernel. You will have to select the
 338           IPL device.
 339
 340 choice
 341         prompt "IPL method generated into head.S"
 342         depends on IPL
 343         default IPL_TAPE
 344         help
 345           Select "tape" if you want to IPL the image from a Tape.
 346
 347           Select "vm_reader" if you are running under VM/ESA and want
 348           to IPL the image from the emulated card reader.
 349
 350 config IPL_TAPE
 351         bool "tape"
 352
 353 config IPL_VM
 354         bool "vm_reader"
 355
 356 endchoice
 357
 358 source "fs/Kconfig.binfmt"
 359
 360 config FORCE_MAX_ZONEORDER
 361         int
 362         default "9"
 363
 364 config PROCESS_DEBUG
 365         bool "Show crashed user process info"
 366         help
 367           Say Y to print all process fault locations to the console.  This is
 368           a debugging option; you probably do not want to set it unless you
 369           are an S390 port maintainer.
 370
 371 config PFAULT
 372         bool "Pseudo page fault support"
 373         help
 374           Select this option, if you want to use PFAULT pseudo page fault
 375           handling under VM. If running native or in LPAR, this option
 376           has no effect. If your VM does not support PFAULT, PAGEEX
 377           pseudo page fault handling will be used.
 378           Note that VM 4.2 supports PFAULT but has a bug in its
 379           implementation that causes some problems.
 380           Everybody who wants to run Linux under VM != VM4.2 should select
 381           this option.
 382
 383 config SHARED_KERNEL
 384         bool "VM shared kernel support"
 385         help
 386           Select this option, if you want to share the text segment of the
 387           Linux kernel between different VM guests. This reduces memory
 388           usage with lots of guests but greatly increases kernel size.
 389           Also if a kernel was IPL'ed from a shared segment the kexec system
 390           call will not work.
 391           You should only select this option if you know what you are
 392           doing and want to exploit this feature.
 393
 394 config CMM
 395         tristate "Cooperative memory management"
 396         help
 397           Select this option, if you want to enable the kernel interface
 398           to reduce the memory size of the system. This is accomplished
 399           by allocating pages of memory and put them "on hold". This only
 400           makes sense for a system running under VM where the unused pages
 401           will be reused by VM for other guest systems. The interface
 402           allows an external monitor to balance memory of many systems.
 403           Everybody who wants to run Linux under VM should select this
 404           option.
 405
 406 config CMM_PROC
 407         bool "/proc interface to cooperative memory management"
 408         depends on CMM
 409         help
 410           Select this option to enable the /proc interface to the
 411           cooperative memory management.
 412
 413 config CMM_IUCV
 414         bool "IUCV special message interface to cooperative memory management"
 415         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 416         help
 417           Select this option to enable the special message interface to
 418           the cooperative memory management.
 419
 420 config VIRT_TIMER
 421         bool "Virtual CPU timer support"
 422         help
 423           This provides a kernel interface for virtual CPU timers.
 424           Default is disabled.
 425
 426 config VIRT_CPU_ACCOUNTING
 427         bool "Base user process accounting on virtual cpu timer"
 428         depends on VIRT_TIMER
 429         help
 430           Select this option to use CPU timer deltas to do user
 431           process accounting.
 432
 433 config APPLDATA_BASE
 434         bool "Linux - VM Monitor Stream, base infrastructure"
 435         depends on PROC_FS && VIRT_TIMER=y
 436         help
 437           This provides a kernel interface for creating and updating z/VM APPLDATA
 438           monitor records. The monitor records are updated at certain time
 439           intervals, once the timer is started.
 440           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 441           i.e. enables or disables monitoring on the Linux side.
 442           A custom interval value (in seconds) can be written to
 443           /proc/appldata/interval.
 444
 445           Defaults are 60 seconds interval and timer off.
 446           The /proc entries can also be read from, showing the current settings.
 447
 448 config APPLDATA_MEM
 449         tristate "Monitor memory management statistics"
 450         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 451         help
 452           This provides memory management related data to the Linux - VM Monitor
 453           Stream, like paging/swapping rate, memory utilisation, etc.
 454           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 455           APPLDATA monitor record, i.e. enables or disables monitoring this record
 456           on the z/VM side.
 457
 458           Default is disabled.
 459           The /proc entry can also be read from, showing the current settings.
 460
 461           This can also be compiled as a module, which will be called
 462           appldata_mem.o.
 463
 464 config APPLDATA_OS
 465         tristate "Monitor OS statistics"
 466         depends on APPLDATA_BASE
 467         help
 468           This provides OS related data to the Linux - VM Monitor Stream, like
 469           CPU utilisation, etc.
 470           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 471           APPLDATA monitor record, i.e. enables or disables monitoring this record
 472           on the z/VM side.
 473
 474           Default is disabled.
 475           This can also be compiled as a module, which will be called
 476           appldata_os.o.
 477
 478 config APPLDATA_NET_SUM
 479         tristate "Monitor overall network statistics"
 480         depends on APPLDATA_BASE
 481         help
 482           This provides network related data to the Linux - VM Monitor Stream,
 483           currently there is only a total sum of network I/O statistics, no
 484           per-interface data.
 485           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 486           APPLDATA monitor record, i.e. enables or disables monitoring this record
 487           on the z/VM side.
 488
 489           Default is disabled.
 490           This can also be compiled as a module, which will be called
 491           appldata_net_sum.o.
 492
 493 source kernel/Kconfig.hz
 494
 495 config S390_HYPFS_FS
 496         bool "s390 hypervisor file system support"
 497         select SYS_HYPERVISOR
 498         default y
 499         help
 500           This is a virtual file system intended to provide accounting
 501           information in an s390 hypervisor environment.
 502
 503 config KEXEC
 504         bool "kexec system call"
 505         help
 506           kexec is a system call that implements the ability to shutdown your
 507           current kernel, and to start another kernel.  It is like a reboot
 508           but is independent of hardware/microcode support.
 509
 510 config ZFCPDUMP
 511         tristate "zfcpdump support"
 512         select SMP
 513         default n
 514         help
 515           Select this option if you want to build an zfcpdump enabled kernel.
 516           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 517
 518 endmenu
 519
 520 source "net/Kconfig"
 521
 522 config PCMCIA
 523         def_bool n
 524
 525 config CCW
 526         def_bool y
 527
 528 source "drivers/Kconfig"
 529
 530 source "fs/Kconfig"
 531
 532 source "arch/s390/Kconfig.debug"
 533
 534 source "security/Kconfig"
 535
 536 source "crypto/Kconfig"
 537
 538 source "lib/Kconfig"