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