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