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 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  76         def_bool y
  77
  78 mainmenu "Linux Kernel Configuration"
  79
  80 config S390
  81         def_bool y
  82         select USE_GENERIC_SMP_HELPERS if SMP
  83         select HAVE_SYSCALL_WRAPPERS
  84         select HAVE_FUNCTION_TRACER
  85         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  86         select HAVE_FTRACE_MCOUNT_RECORD
  87         select HAVE_FTRACE_SYSCALLS
  88         select HAVE_DYNAMIC_FTRACE
  89         select HAVE_FUNCTION_GRAPH_TRACER
  90         select HAVE_DEFAULT_NO_SPIN_MUTEXES
  91         select HAVE_OPROFILE
  92         select HAVE_KPROBES
  93         select HAVE_KRETPROBES
  94         select HAVE_KVM if 64BIT
  95         select HAVE_ARCH_TRACEHOOK
  96         select INIT_ALL_POSSIBLE
  97
  98 source "init/Kconfig"
  99
 100 source "kernel/Kconfig.freezer"
 101
 102 menu "Base setup"
 103
 104 comment "Processor type and features"
 105
 106 source "kernel/time/Kconfig"
 107
 108 config 64BIT
 109         bool "64 bit kernel"
 110         help
 111           Select this option if you have a 64 bit IBM zSeries machine
 112           and want to use the 64 bit addressing mode.
 113
 114 config 32BIT
 115         bool
 116         default y if !64BIT
 117
 118 config SMP
 119         bool "Symmetric multi-processing support"
 120         ---help---
 121           This enables support for systems with more than one CPU. If you have
 122           a system with only one CPU, like most personal computers, say N. If
 123           you have a system with more than one CPU, say Y.
 124
 125           If you say N here, the kernel will run on single and multiprocessor
 126           machines, but will use only one CPU of a multiprocessor machine. If
 127           you say Y here, the kernel will run on many, but not all,
 128           singleprocessor machines. On a singleprocessor machine, the kernel
 129           will run faster if you say N here.
 130
 131           See also the SMP-HOWTO available at
 132           <http://www.tldp.org/docs.html#howto>.
 133
 134           Even if you don't know what to do here, say Y.
 135
 136 config NR_CPUS
 137         int "Maximum number of CPUs (2-64)"
 138         range 2 64
 139         depends on SMP
 140         default "32" if !64BIT
 141         default "64" if 64BIT
 142         help
 143           This allows you to specify the maximum number of CPUs which this
 144           kernel will support.  The maximum supported value is 64 and the
 145           minimum value which makes sense is 2.
 146
 147           This is purely to save memory - each supported CPU adds
 148           approximately sixteen kilobytes to the kernel image.
 149
 150 config HOTPLUG_CPU
 151         bool "Support for hot-pluggable CPUs"
 152         depends on SMP
 153         select HOTPLUG
 154         default n
 155         help
 156           Say Y here to be able to turn CPUs off and on. CPUs
 157           can be controlled through /sys/devices/system/cpu/cpu#.
 158           Say N if you want to disable CPU hotplug.
 159
 160 config MATHEMU
 161         bool "IEEE FPU emulation"
 162         depends on MARCH_G5
 163         help
 164           This option is required for IEEE compliant floating point arithmetic
 165           on older S/390 machines. Say Y unless you know your machine doesn't
 166           need this.
 167
 168 config COMPAT
 169         bool "Kernel support for 31 bit emulation"
 170         depends on 64BIT
 171         select COMPAT_BINFMT_ELF
 172         help
 173           Select this option if you want to enable your system kernel to
 174           handle system-calls from ELF binaries for 31 bit ESA.  This option
 175           (and some other stuff like libraries and such) is needed for
 176           executing 31 bit applications.  It is safe to say "Y".
 177
 178 config SYSVIPC_COMPAT
 179         bool
 180         depends on COMPAT && SYSVIPC
 181         default y
 182
 183 config AUDIT_ARCH
 184         bool
 185         default y
 186
 187 config S390_SWITCH_AMODE
 188         bool "Switch kernel/user addressing modes"
 189         help
 190           This option allows to switch the addressing modes of kernel and user
 191           space. The kernel parameter switch_amode=on will enable this feature,
 192           default is disabled. Enabling this (via kernel parameter) on machines
 193           earlier than IBM System z9-109 EC/BC will reduce system performance.
 194
 195           Note that this option will also be selected by selecting the execute
 196           protection option below. Enabling the execute protection via the
 197           noexec kernel parameter will also switch the addressing modes,
 198           independent of the switch_amode kernel parameter.
 199
 200
 201 config S390_EXEC_PROTECT
 202         bool "Data execute protection"
 203         select S390_SWITCH_AMODE
 204         help
 205           This option allows to enable a buffer overflow protection for user
 206           space programs and it also selects the addressing mode option above.
 207           The kernel parameter noexec=on will enable this feature and also
 208           switch the addressing modes, default is disabled. Enabling this (via
 209           kernel parameter) on machines earlier than IBM System z9-109 EC/BC
 210           will reduce system performance.
 211
 212 comment "Code generation options"
 213
 214 choice
 215         prompt "Processor type"
 216         default MARCH_G5
 217
 218 config MARCH_G5
 219         bool "S/390 model G5 and G6"
 220         depends on !64BIT
 221         help
 222           Select this to build a 31 bit kernel that works
 223           on all S/390 and zSeries machines.
 224
 225 config MARCH_Z900
 226         bool "IBM eServer zSeries model z800 and z900"
 227         help
 228           Select this to optimize for zSeries machines. This
 229           will enable some optimizations that are not available
 230           on older 31 bit only CPUs.
 231
 232 config MARCH_Z990
 233         bool "IBM eServer zSeries model z890 and z990"
 234         help
 235           Select this enable optimizations for model z890/z990.
 236           This will be slightly faster but does not work on
 237           older machines such as the z900.
 238
 239 config MARCH_Z9_109
 240         bool "IBM System z9"
 241         help
 242           Select this to enable optimizations for IBM System z9-109, IBM
 243           System z9 Enterprise Class (z9 EC), and IBM System z9 Business
 244           Class (z9 BC). The kernel will be slightly faster but will not
 245           work on older machines such as the z990, z890, z900, and z800.
 246
 247 config MARCH_Z10
 248         bool "IBM System z10"
 249         help
 250           Select this to enable optimizations for IBM System z10. The
 251           kernel will be slightly faster but will not work on older
 252           machines such as the z990, z890, z900, z800, z9-109, z9-ec
 253           and z9-bc.
 254
 255 endchoice
 256
 257 config PACK_STACK
 258         bool "Pack kernel stack"
 259         help
 260           This option enables the compiler option -mkernel-backchain if it
 261           is available. If the option is available the compiler supports
 262           the new stack layout which dramatically reduces the minimum stack
 263           frame size. With an old compiler a non-leaf function needs a
 264           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 265           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 266           and 24 byte on 64 bit.
 267
 268           Say Y if you are unsure.
 269
 270 config SMALL_STACK
 271         bool "Use 8kb for kernel stack instead of 16kb"
 272         depends on PACK_STACK && 64BIT && !LOCKDEP
 273         help
 274           If you say Y here and the compiler supports the -mkernel-backchain
 275           option the kernel will use a smaller kernel stack size. The reduced
 276           size is 8kb instead of 16kb. This allows to run more threads on a
 277           system and reduces the pressure on the memory management for higher
 278           order page allocations.
 279
 280           Say N if you are unsure.
 281
 282 config CHECK_STACK
 283         bool "Detect kernel stack overflow"
 284         help
 285           This option enables the compiler option -mstack-guard and
 286           -mstack-size if they are available. If the compiler supports them
 287           it will emit additional code to each function prolog to trigger
 288           an illegal operation if the kernel stack is about to overflow.
 289
 290           Say N if you are unsure.
 291
 292 config STACK_GUARD
 293         int "Size of the guard area (128-1024)"
 294         range 128 1024
 295         depends on CHECK_STACK
 296         default "256"
 297         help
 298           This allows you to specify the size of the guard area at the lower
 299           end of the kernel stack. If the kernel stack points into the guard
 300           area on function entry an illegal operation is triggered. The size
 301           needs to be a power of 2. Please keep in mind that the size of an
 302           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 303           The minimum size for the stack guard should be 256 for 31 bit and
 304           512 for 64 bit.
 305
 306 config WARN_STACK
 307         bool "Emit compiler warnings for function with broken stack usage"
 308         help
 309           This option enables the compiler options -mwarn-framesize and
 310           -mwarn-dynamicstack. If the compiler supports these options it
 311           will generate warnings for function which either use alloca or
 312           create a stack frame bigger than CONFIG_WARN_STACK_SIZE.
 313
 314           Say N if you are unsure.
 315
 316 config WARN_STACK_SIZE
 317         int "Maximum frame size considered safe (128-2048)"
 318         range 128 2048
 319         depends on WARN_STACK
 320         default "2048"
 321         help
 322           This allows you to specify the maximum frame size a function may
 323           have without the compiler complaining about it.
 324
 325 config ARCH_POPULATES_NODE_MAP
 326         def_bool y
 327
 328 comment "Kernel preemption"
 329
 330 source "kernel/Kconfig.preempt"
 331
 332 config ARCH_SPARSEMEM_ENABLE
 333         def_bool y
 334         select SPARSEMEM_VMEMMAP_ENABLE
 335         select SPARSEMEM_VMEMMAP
 336         select SPARSEMEM_STATIC if !64BIT
 337
 338 config ARCH_SPARSEMEM_DEFAULT
 339         def_bool y
 340
 341 config ARCH_SELECT_MEMORY_MODEL
 342        def_bool y
 343
 344 config ARCH_ENABLE_MEMORY_HOTPLUG
 345         def_bool y
 346         depends on SPARSEMEM
 347
 348 config ARCH_ENABLE_MEMORY_HOTREMOVE
 349         def_bool y
 350
 351 source "mm/Kconfig"
 352
 353 comment "I/O subsystem configuration"
 354
 355 config QDIO
 356         tristate "QDIO support"
 357         ---help---
 358           This driver provides the Queued Direct I/O base support for
 359           IBM System z.
 360
 361           To compile this driver as a module, choose M here: the
 362           module will be called qdio.
 363
 364           If unsure, say Y.
 365
 366 config CHSC_SCH
 367         tristate "Support for CHSC subchannels"
 368         help
 369           This driver allows usage of CHSC subchannels. A CHSC subchannel
 370           is usually present on LPAR only.
 371           The driver creates a device /dev/chsc, which may be used to
 372           obtain I/O configuration information about the machine and
 373           to issue asynchronous chsc commands (DANGEROUS).
 374           You will usually only want to use this interface on a special
 375           LPAR designated for system management.
 376
 377           To compile this driver as a module, choose M here: the
 378           module will be called chsc_sch.
 379
 380           If unsure, say N.
 381
 382 comment "Misc"
 383
 384 config IPL
 385         bool "Builtin IPL record support"
 386         help
 387           If you want to use the produced kernel to IPL directly from a
 388           device, you have to merge a bootsector specific to the device
 389           into the first bytes of the kernel. You will have to select the
 390           IPL device.
 391
 392 choice
 393         prompt "IPL method generated into head.S"
 394         depends on IPL
 395         default IPL_VM
 396         help
 397           Select "tape" if you want to IPL the image from a Tape.
 398
 399           Select "vm_reader" if you are running under VM/ESA and want
 400           to IPL the image from the emulated card reader.
 401
 402 config IPL_TAPE
 403         bool "tape"
 404
 405 config IPL_VM
 406         bool "vm_reader"
 407
 408 endchoice
 409
 410 source "fs/Kconfig.binfmt"
 411
 412 config FORCE_MAX_ZONEORDER
 413         int
 414         default "9"
 415
 416 config PROCESS_DEBUG
 417         bool "Show crashed user process info"
 418         help
 419           Say Y to print all process fault locations to the console.  This is
 420           a debugging option; you probably do not want to set it unless you
 421           are an S390 port maintainer.
 422
 423 config PFAULT
 424         bool "Pseudo page fault support"
 425         help
 426           Select this option, if you want to use PFAULT pseudo page fault
 427           handling under VM. If running native or in LPAR, this option
 428           has no effect. If your VM does not support PFAULT, PAGEEX
 429           pseudo page fault handling will be used.
 430           Note that VM 4.2 supports PFAULT but has a bug in its
 431           implementation that causes some problems.
 432           Everybody who wants to run Linux under VM != VM4.2 should select
 433           this option.
 434
 435 config SHARED_KERNEL
 436         bool "VM shared kernel support"
 437         help
 438           Select this option, if you want to share the text segment of the
 439           Linux kernel between different VM guests. This reduces memory
 440           usage with lots of guests but greatly increases kernel size.
 441           Also if a kernel was IPL'ed from a shared segment the kexec system
 442           call will not work.
 443           You should only select this option if you know what you are
 444           doing and want to exploit this feature.
 445
 446 config CMM
 447         tristate "Cooperative memory management"
 448         help
 449           Select this option, if you want to enable the kernel interface
 450           to reduce the memory size of the system. This is accomplished
 451           by allocating pages of memory and put them "on hold". This only
 452           makes sense for a system running under VM where the unused pages
 453           will be reused by VM for other guest systems. The interface
 454           allows an external monitor to balance memory of many systems.
 455           Everybody who wants to run Linux under VM should select this
 456           option.
 457
 458 config CMM_PROC
 459         bool "/proc interface to cooperative memory management"
 460         depends on CMM
 461         help
 462           Select this option to enable the /proc interface to the
 463           cooperative memory management.
 464
 465 config CMM_IUCV
 466         bool "IUCV special message interface to cooperative memory management"
 467         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 468         help
 469           Select this option to enable the special message interface to
 470           the cooperative memory management.
 471
 472 config PAGE_STATES
 473         bool "Unused page notification"
 474         help
 475           This enables the notification of unused pages to the
 476           hypervisor. The ESSA instruction is used to do the states
 477           changes between a page that has content and the unused state.
 478
 479 config APPLDATA_BASE
 480         bool "Linux - VM Monitor Stream, base infrastructure"
 481         depends on PROC_FS
 482         help
 483           This provides a kernel interface for creating and updating z/VM APPLDATA
 484           monitor records. The monitor records are updated at certain time
 485           intervals, once the timer is started.
 486           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 487           i.e. enables or disables monitoring on the Linux side.
 488           A custom interval value (in seconds) can be written to
 489           /proc/appldata/interval.
 490
 491           Defaults are 60 seconds interval and timer off.
 492           The /proc entries can also be read from, showing the current settings.
 493
 494 config APPLDATA_MEM
 495         tristate "Monitor memory management statistics"
 496         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 497         help
 498           This provides memory management related data to the Linux - VM Monitor
 499           Stream, like paging/swapping rate, memory utilisation, etc.
 500           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 501           APPLDATA monitor record, i.e. enables or disables monitoring this record
 502           on the z/VM side.
 503
 504           Default is disabled.
 505           The /proc entry can also be read from, showing the current settings.
 506
 507           This can also be compiled as a module, which will be called
 508           appldata_mem.o.
 509
 510 config APPLDATA_OS
 511         tristate "Monitor OS statistics"
 512         depends on APPLDATA_BASE
 513         help
 514           This provides OS related data to the Linux - VM Monitor Stream, like
 515           CPU utilisation, etc.
 516           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 517           APPLDATA monitor record, i.e. enables or disables monitoring this record
 518           on the z/VM side.
 519
 520           Default is disabled.
 521           This can also be compiled as a module, which will be called
 522           appldata_os.o.
 523
 524 config APPLDATA_NET_SUM
 525         tristate "Monitor overall network statistics"
 526         depends on APPLDATA_BASE && NET
 527         help
 528           This provides network related data to the Linux - VM Monitor Stream,
 529           currently there is only a total sum of network I/O statistics, no
 530           per-interface data.
 531           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 532           APPLDATA monitor record, i.e. enables or disables monitoring this record
 533           on the z/VM side.
 534
 535           Default is disabled.
 536           This can also be compiled as a module, which will be called
 537           appldata_net_sum.o.
 538
 539 source kernel/Kconfig.hz
 540
 541 config S390_HYPFS_FS
 542         bool "s390 hypervisor file system support"
 543         select SYS_HYPERVISOR
 544         default y
 545         help
 546           This is a virtual file system intended to provide accounting
 547           information in an s390 hypervisor environment.
 548
 549 config KEXEC
 550         bool "kexec system call"
 551         help
 552           kexec is a system call that implements the ability to shutdown your
 553           current kernel, and to start another kernel.  It is like a reboot
 554           but is independent of hardware/microcode support.
 555
 556 config ZFCPDUMP
 557         bool "zfcpdump support"
 558         select SMP
 559         default n
 560         help
 561           Select this option if you want to build an zfcpdump enabled kernel.
 562           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 563
 564 config S390_GUEST
 565 bool "s390 guest support for KVM (EXPERIMENTAL)"
 566         depends on 64BIT && EXPERIMENTAL
 567         select VIRTIO
 568         select VIRTIO_RING
 569         select VIRTIO_CONSOLE
 570         help
 571           Select this option if you want to run the kernel as a guest under
 572           the KVM hypervisor. This will add detection for KVM as well  as a
 573           virtio transport. If KVM is detected, the virtio console will be
 574           the default console.
 575
 576 config SECCOMP
 577         bool "Enable seccomp to safely compute untrusted bytecode"
 578         depends on PROC_FS
 579         default y
 580         help
 581           This kernel feature is useful for number crunching applications
 582           that may need to compute untrusted bytecode during their
 583           execution. By using pipes or other transports made available to
 584           the process as file descriptors supporting the read/write
 585           syscalls, it's possible to isolate those applications in
 586           their own address space using seccomp. Once seccomp is
 587           enabled via /proc/<pid>/seccomp, it cannot be disabled
 588           and the task is only allowed to execute a few safe syscalls
 589           defined by each seccomp mode.
 590
 591           If unsure, say Y.
 592
 593 endmenu
 594
 595 source "net/Kconfig"
 596
 597 config PCMCIA
 598         def_bool n
 599
 600 config CCW
 601         def_bool y
 602
 603 source "drivers/Kconfig"
 604
 605 source "fs/Kconfig"
 606
 607 source "arch/s390/Kconfig.debug"
 608
 609 source "security/Kconfig"
 610
 611 source "crypto/Kconfig"
 612
 613 source "lib/Kconfig"
 614
 615 source "arch/s390/kvm/Kconfig"