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 config PGSTE
  66         bool
  67         default y if KVM
  68
  69 mainmenu "Linux Kernel Configuration"
  70
  71 config S390
  72         def_bool y
  73         select HAVE_OPROFILE
  74         select HAVE_KPROBES
  75         select HAVE_KRETPROBES
  76         select HAVE_KVM if 64BIT
  77
  78 source "init/Kconfig"
  79
  80 menu "Base setup"
  81
  82 comment "Processor type and features"
  83
  84 source "kernel/time/Kconfig"
  85
  86 config 64BIT
  87         bool "64 bit kernel"
  88         help
  89           Select this option if you have a 64 bit IBM zSeries machine
  90           and want to use the 64 bit addressing mode.
  91
  92 config 32BIT
  93         bool
  94         default y if !64BIT
  95
  96 config SMP
  97         bool "Symmetric multi-processing support"
  98         ---help---
  99           This enables support for systems with more than one CPU. If you have
 100           a system with only one CPU, like most personal computers, say N. If
 101           you have a system with more than one CPU, say Y.
 102
 103           If you say N here, the kernel will run on single and multiprocessor
 104           machines, but will use only one CPU of a multiprocessor machine. If
 105           you say Y here, the kernel will run on many, but not all,
 106           singleprocessor machines. On a singleprocessor machine, the kernel
 107           will run faster if you say N here.
 108
 109           See also the SMP-HOWTO available at
 110           <http://www.tldp.org/docs.html#howto>.
 111
 112           Even if you don't know what to do here, say Y.
 113
 114 config NR_CPUS
 115         int "Maximum number of CPUs (2-64)"
 116         range 2 64
 117         depends on SMP
 118         default "32" if !64BIT
 119         default "64" if 64BIT
 120         help
 121           This allows you to specify the maximum number of CPUs which this
 122           kernel will support.  The maximum supported value is 64 and the
 123           minimum value which makes sense is 2.
 124
 125           This is purely to save memory - each supported CPU adds
 126           approximately sixteen kilobytes to the kernel image.
 127
 128 config HOTPLUG_CPU
 129         bool "Support for hot-pluggable CPUs"
 130         depends on SMP
 131         select HOTPLUG
 132         default n
 133         help
 134           Say Y here to be able to turn CPUs off and on. CPUs
 135           can be controlled through /sys/devices/system/cpu/cpu#.
 136           Say N if you want to disable CPU hotplug.
 137
 138 config MATHEMU
 139         bool "IEEE FPU emulation"
 140         depends on MARCH_G5
 141         help
 142           This option is required for IEEE compliant floating point arithmetic
 143           on older S/390 machines. Say Y unless you know your machine doesn't
 144           need this.
 145
 146 config COMPAT
 147         bool "Kernel support for 31 bit emulation"
 148         depends on 64BIT
 149         select COMPAT_BINFMT_ELF
 150         help
 151           Select this option if you want to enable your system kernel to
 152           handle system-calls from ELF binaries for 31 bit ESA.  This option
 153           (and some other stuff like libraries and such) is needed for
 154           executing 31 bit applications.  It is safe to say "Y".
 155
 156 config SYSVIPC_COMPAT
 157         bool
 158         depends on COMPAT && SYSVIPC
 159         default y
 160
 161 config AUDIT_ARCH
 162         bool
 163         default y
 164
 165 config S390_SWITCH_AMODE
 166         bool "Switch kernel/user addressing modes"
 167         help
 168           This option allows to switch the addressing modes of kernel and user
 169           space. The kernel parameter switch_amode=on will enable this feature,
 170           default is disabled. Enabling this (via kernel parameter) on machines
 171           earlier than IBM System z9-109 EC/BC will reduce system performance.
 172
 173           Note that this option will also be selected by selecting the execute
 174           protection option below. Enabling the execute protection via the
 175           noexec kernel parameter will also switch the addressing modes,
 176           independent of the switch_amode kernel parameter.
 177
 178
 179 config S390_EXEC_PROTECT
 180         bool "Data execute protection"
 181         select S390_SWITCH_AMODE
 182         help
 183           This option allows to enable a buffer overflow protection for user
 184           space programs and it also selects the addressing mode option above.
 185           The kernel parameter noexec=on will enable this feature and also
 186           switch the addressing modes, default is disabled. Enabling this (via
 187           kernel parameter) on machines earlier than IBM System z9-109 EC/BC
 188           will reduce system performance.
 189
 190 comment "Code generation options"
 191
 192 choice
 193         prompt "Processor type"
 194         default MARCH_G5
 195
 196 config MARCH_G5
 197         bool "S/390 model G5 and G6"
 198         depends on !64BIT
 199         help
 200           Select this to build a 31 bit kernel that works
 201           on all S/390 and zSeries machines.
 202
 203 config MARCH_Z900
 204         bool "IBM eServer zSeries model z800 and z900"
 205         help
 206           Select this to optimize for zSeries machines. This
 207           will enable some optimizations that are not available
 208           on older 31 bit only CPUs.
 209
 210 config MARCH_Z990
 211         bool "IBM eServer zSeries model z890 and z990"
 212         help
 213           Select this enable optimizations for model z890/z990.
 214           This will be slightly faster but does not work on
 215           older machines such as the z900.
 216
 217 config MARCH_Z9_109
 218         bool "IBM System z9"
 219         help
 220           Select this to enable optimizations for IBM System z9-109, IBM
 221           System z9 Enterprise Class (z9 EC), and IBM System z9 Business
 222           Class (z9 BC). The kernel will be slightly faster but will not
 223           work on older machines such as the z990, z890, z900, and z800.
 224
 225 endchoice
 226
 227 config PACK_STACK
 228         bool "Pack kernel stack"
 229         help
 230           This option enables the compiler option -mkernel-backchain if it
 231           is available. If the option is available the compiler supports
 232           the new stack layout which dramatically reduces the minimum stack
 233           frame size. With an old compiler a non-leaf function needs a
 234           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 235           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 236           and 24 byte on 64 bit.
 237
 238           Say Y if you are unsure.
 239
 240 config SMALL_STACK
 241         bool "Use 4kb/8kb for kernel stack instead of 8kb/16kb"
 242         depends on PACK_STACK && !LOCKDEP
 243         help
 244           If you say Y here and the compiler supports the -mkernel-backchain
 245           option the kernel will use a smaller kernel stack size. For 31 bit
 246           the reduced size is 4kb instead of 8kb and for 64 bit it is 8kb
 247           instead of 16kb. This allows to run more thread on a system and
 248           reduces the pressure on the memory management for higher order
 249           page allocations.
 250
 251           Say N if you are unsure.
 252
 253
 254 config CHECK_STACK
 255         bool "Detect kernel stack overflow"
 256         help
 257           This option enables the compiler option -mstack-guard and
 258           -mstack-size if they are available. If the compiler supports them
 259           it will emit additional code to each function prolog to trigger
 260           an illegal operation if the kernel stack is about to overflow.
 261
 262           Say N if you are unsure.
 263
 264 config STACK_GUARD
 265         int "Size of the guard area (128-1024)"
 266         range 128 1024
 267         depends on CHECK_STACK
 268         default "256"
 269         help
 270           This allows you to specify the size of the guard area at the lower
 271           end of the kernel stack. If the kernel stack points into the guard
 272           area on function entry an illegal operation is triggered. The size
 273           needs to be a power of 2. Please keep in mind that the size of an
 274           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 275           The minimum size for the stack guard should be 256 for 31 bit and
 276           512 for 64 bit.
 277
 278 config WARN_STACK
 279         bool "Emit compiler warnings for function with broken stack usage"
 280         help
 281           This option enables the compiler options -mwarn-framesize and
 282           -mwarn-dynamicstack. If the compiler supports these options it
 283           will generate warnings for function which either use alloca or
 284           create a stack frame bigger then CONFIG_WARN_STACK_SIZE.
 285
 286           Say N if you are unsure.
 287
 288 config WARN_STACK_SIZE
 289         int "Maximum frame size considered safe (128-2048)"
 290         range 128 2048
 291         depends on WARN_STACK
 292         default "256"
 293         help
 294           This allows you to specify the maximum frame size a function may
 295           have without the compiler complaining about it.
 296
 297 config ARCH_POPULATES_NODE_MAP
 298         def_bool y
 299
 300 comment "Kernel preemption"
 301
 302 source "kernel/Kconfig.preempt"
 303
 304 config ARCH_SPARSEMEM_ENABLE
 305         def_bool y
 306         select SPARSEMEM_VMEMMAP_ENABLE
 307         select SPARSEMEM_VMEMMAP
 308         select SPARSEMEM_STATIC if !64BIT
 309
 310 config ARCH_SPARSEMEM_DEFAULT
 311         def_bool y
 312
 313 config ARCH_SELECT_MEMORY_MODEL
 314        def_bool y
 315
 316 source "mm/Kconfig"
 317
 318 comment "I/O subsystem configuration"
 319
 320 config MACHCHK_WARNING
 321         bool "Process warning machine checks"
 322         help
 323           Select this option if you want the machine check handler on IBM S/390 or
 324           zSeries to process warning machine checks (e.g. on power failures).
 325           If unsure, say "Y".
 326
 327 config QDIO
 328         tristate "QDIO support"
 329         ---help---
 330           This driver provides the Queued Direct I/O base support for
 331           IBM System z.
 332
 333           To compile this driver as a module, choose M here: the
 334           module will be called qdio.
 335
 336           If unsure, say Y.
 337
 338 config QDIO_DEBUG
 339         bool "Extended debugging information"
 340         depends on QDIO
 341         help
 342           Say Y here to get extended debugging output in
 343             /sys/kernel/debug/s390dbf/qdio...
 344           Warning: this option reduces the performance of the QDIO module.
 345
 346           If unsure, say N.
 347
 348 config CHSC_SCH
 349         tristate "Support for CHSC subchannels"
 350         help
 351           This driver allows usage of CHSC subchannels. A CHSC subchannel
 352           is usually present on LPAR only.
 353           The driver creates a device /dev/chsc, which may be used to
 354           obtain I/O configuration information about the machine and
 355           to issue asynchronous chsc commands (DANGEROUS).
 356           You will usually only want to use this interface on a special
 357           LPAR designated for system management.
 358
 359           To compile this driver as a module, choose M here: the
 360           module will be called chsc_sch.
 361
 362           If unsure, say N.
 363
 364 comment "Misc"
 365
 366 config IPL
 367         bool "Builtin IPL record support"
 368         help
 369           If you want to use the produced kernel to IPL directly from a
 370           device, you have to merge a bootsector specific to the device
 371           into the first bytes of the kernel. You will have to select the
 372           IPL device.
 373
 374 choice
 375         prompt "IPL method generated into head.S"
 376         depends on IPL
 377         default IPL_TAPE
 378         help
 379           Select "tape" if you want to IPL the image from a Tape.
 380
 381           Select "vm_reader" if you are running under VM/ESA and want
 382           to IPL the image from the emulated card reader.
 383
 384 config IPL_TAPE
 385         bool "tape"
 386
 387 config IPL_VM
 388         bool "vm_reader"
 389
 390 endchoice
 391
 392 source "fs/Kconfig.binfmt"
 393
 394 config FORCE_MAX_ZONEORDER
 395         int
 396         default "9"
 397
 398 config PROCESS_DEBUG
 399         bool "Show crashed user process info"
 400         help
 401           Say Y to print all process fault locations to the console.  This is
 402           a debugging option; you probably do not want to set it unless you
 403           are an S390 port maintainer.
 404
 405 config PFAULT
 406         bool "Pseudo page fault support"
 407         help
 408           Select this option, if you want to use PFAULT pseudo page fault
 409           handling under VM. If running native or in LPAR, this option
 410           has no effect. If your VM does not support PFAULT, PAGEEX
 411           pseudo page fault handling will be used.
 412           Note that VM 4.2 supports PFAULT but has a bug in its
 413           implementation that causes some problems.
 414           Everybody who wants to run Linux under VM != VM4.2 should select
 415           this option.
 416
 417 config SHARED_KERNEL
 418         bool "VM shared kernel support"
 419         help
 420           Select this option, if you want to share the text segment of the
 421           Linux kernel between different VM guests. This reduces memory
 422           usage with lots of guests but greatly increases kernel size.
 423           Also if a kernel was IPL'ed from a shared segment the kexec system
 424           call will not work.
 425           You should only select this option if you know what you are
 426           doing and want to exploit this feature.
 427
 428 config CMM
 429         tristate "Cooperative memory management"
 430         help
 431           Select this option, if you want to enable the kernel interface
 432           to reduce the memory size of the system. This is accomplished
 433           by allocating pages of memory and put them "on hold". This only
 434           makes sense for a system running under VM where the unused pages
 435           will be reused by VM for other guest systems. The interface
 436           allows an external monitor to balance memory of many systems.
 437           Everybody who wants to run Linux under VM should select this
 438           option.
 439
 440 config CMM_PROC
 441         bool "/proc interface to cooperative memory management"
 442         depends on CMM
 443         help
 444           Select this option to enable the /proc interface to the
 445           cooperative memory management.
 446
 447 config CMM_IUCV
 448         bool "IUCV special message interface to cooperative memory management"
 449         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 450         help
 451           Select this option to enable the special message interface to
 452           the cooperative memory management.
 453
 454 config PAGE_STATES
 455         bool "Unused page notification"
 456         help
 457           This enables the notification of unused pages to the
 458           hypervisor. The ESSA instruction is used to do the states
 459           changes between a page that has content and the unused state.
 460
 461 config VIRT_TIMER
 462         bool "Virtual CPU timer support"
 463         help
 464           This provides a kernel interface for virtual CPU timers.
 465           Default is disabled.
 466
 467 config VIRT_CPU_ACCOUNTING
 468         bool "Base user process accounting on virtual cpu timer"
 469         depends on VIRT_TIMER
 470         help
 471           Select this option to use CPU timer deltas to do user
 472           process accounting.
 473
 474 config APPLDATA_BASE
 475         bool "Linux - VM Monitor Stream, base infrastructure"
 476         depends on PROC_FS && VIRT_TIMER=y
 477         help
 478           This provides a kernel interface for creating and updating z/VM APPLDATA
 479           monitor records. The monitor records are updated at certain time
 480           intervals, once the timer is started.
 481           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 482           i.e. enables or disables monitoring on the Linux side.
 483           A custom interval value (in seconds) can be written to
 484           /proc/appldata/interval.
 485
 486           Defaults are 60 seconds interval and timer off.
 487           The /proc entries can also be read from, showing the current settings.
 488
 489 config APPLDATA_MEM
 490         tristate "Monitor memory management statistics"
 491         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 492         help
 493           This provides memory management related data to the Linux - VM Monitor
 494           Stream, like paging/swapping rate, memory utilisation, etc.
 495           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 496           APPLDATA monitor record, i.e. enables or disables monitoring this record
 497           on the z/VM side.
 498
 499           Default is disabled.
 500           The /proc entry can also be read from, showing the current settings.
 501
 502           This can also be compiled as a module, which will be called
 503           appldata_mem.o.
 504
 505 config APPLDATA_OS
 506         tristate "Monitor OS statistics"
 507         depends on APPLDATA_BASE
 508         help
 509           This provides OS related data to the Linux - VM Monitor Stream, like
 510           CPU utilisation, etc.
 511           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 512           APPLDATA monitor record, i.e. enables or disables monitoring this record
 513           on the z/VM side.
 514
 515           Default is disabled.
 516           This can also be compiled as a module, which will be called
 517           appldata_os.o.
 518
 519 config APPLDATA_NET_SUM
 520         tristate "Monitor overall network statistics"
 521         depends on APPLDATA_BASE
 522         help
 523           This provides network related data to the Linux - VM Monitor Stream,
 524           currently there is only a total sum of network I/O statistics, no
 525           per-interface data.
 526           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 527           APPLDATA monitor record, i.e. enables or disables monitoring this record
 528           on the z/VM side.
 529
 530           Default is disabled.
 531           This can also be compiled as a module, which will be called
 532           appldata_net_sum.o.
 533
 534 source kernel/Kconfig.hz
 535
 536 config S390_HYPFS_FS
 537         bool "s390 hypervisor file system support"
 538         select SYS_HYPERVISOR
 539         default y
 540         help
 541           This is a virtual file system intended to provide accounting
 542           information in an s390 hypervisor environment.
 543
 544 config KEXEC
 545         bool "kexec system call"
 546         help
 547           kexec is a system call that implements the ability to shutdown your
 548           current kernel, and to start another kernel.  It is like a reboot
 549           but is independent of hardware/microcode support.
 550
 551 config ZFCPDUMP
 552         tristate "zfcpdump support"
 553         select SMP
 554         default n
 555         help
 556           Select this option if you want to build an zfcpdump enabled kernel.
 557           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 558
 559 config S390_GUEST
 560 bool "s390 guest support (EXPERIMENTAL)"
 561         depends on 64BIT && EXPERIMENTAL
 562         select VIRTIO
 563         select VIRTIO_RING
 564         help
 565           Select this option if you want to run the kernel under s390 linux
 566 endmenu
 567
 568 source "net/Kconfig"
 569
 570 config PCMCIA
 571         def_bool n
 572
 573 config CCW
 574         def_bool y
 575
 576 source "drivers/Kconfig"
 577
 578 source "fs/Kconfig"
 579
 580 source "arch/s390/Kconfig.debug"
 581
 582 source "security/Kconfig"
 583
 584 source "crypto/Kconfig"
 585
 586 source "lib/Kconfig"
 587
 588 source "arch/s390/kvm/Kconfig"