arch/s390/Kconfig

   1 config MMU
   2         def_bool y
   3
   4 config ZONE_DMA
   5         def_bool y
   6
   7 config CPU_BIG_ENDIAN
   8         def_bool y
   9
  10 config LOCKDEP_SUPPORT
  11         def_bool y
  12
  13 config STACKTRACE_SUPPORT
  14         def_bool y
  15
  16 config RWSEM_GENERIC_SPINLOCK
  17         bool
  18
  19 config RWSEM_XCHGADD_ALGORITHM
  20         def_bool y
  21
  22 config ARCH_HAS_ILOG2_U32
  23         def_bool n
  24
  25 config ARCH_HAS_ILOG2_U64
  26         def_bool n
  27
  28 config GENERIC_HWEIGHT
  29         def_bool y
  30
  31 config GENERIC_BUG
  32         def_bool y if BUG
  33
  34 config GENERIC_BUG_RELATIVE_POINTERS
  35         def_bool y
  36
  37 config ARCH_DMA_ADDR_T_64BIT
  38         def_bool y
  39
  40 config GENERIC_LOCKBREAK
  41         def_bool y if SMP && PREEMPT
  42
  43 config PGSTE
  44         def_bool y if KVM
  45
  46 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  47         def_bool y
  48
  49 config KEXEC
  50         def_bool y
  51         select KEXEC_CORE
  52
  53 config AUDIT_ARCH
  54         def_bool y
  55
  56 config NO_IOPORT_MAP
  57         def_bool y
  58
  59 config PCI_QUIRKS
  60         def_bool n
  61
  62 config ARCH_SUPPORTS_UPROBES
  63         def_bool y
  64
  65 config S390
  66         def_bool y
  67         select ARCH_BINFMT_ELF_STATE
  68         select ARCH_HAS_DEVMEM_IS_ALLOWED
  69         select ARCH_HAS_ELF_RANDOMIZE
  70         select ARCH_HAS_GCOV_PROFILE_ALL
  71         select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
  72         select ARCH_HAS_KCOV
  73         select ARCH_HAS_SET_MEMORY
  74         select ARCH_HAS_SG_CHAIN
  75         select ARCH_HAS_STRICT_KERNEL_RWX
  76         select ARCH_HAS_STRICT_MODULE_RWX
  77         select ARCH_HAS_UBSAN_SANITIZE_ALL
  78         select ARCH_HAVE_NMI_SAFE_CMPXCHG
  79         select ARCH_INLINE_READ_LOCK
  80         select ARCH_INLINE_READ_LOCK_BH
  81         select ARCH_INLINE_READ_LOCK_IRQ
  82         select ARCH_INLINE_READ_LOCK_IRQSAVE
  83         select ARCH_INLINE_READ_TRYLOCK
  84         select ARCH_INLINE_READ_UNLOCK
  85         select ARCH_INLINE_READ_UNLOCK_BH
  86         select ARCH_INLINE_READ_UNLOCK_IRQ
  87         select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
  88         select ARCH_INLINE_SPIN_LOCK
  89         select ARCH_INLINE_SPIN_LOCK_BH
  90         select ARCH_INLINE_SPIN_LOCK_IRQ
  91         select ARCH_INLINE_SPIN_LOCK_IRQSAVE
  92         select ARCH_INLINE_SPIN_TRYLOCK
  93         select ARCH_INLINE_SPIN_TRYLOCK_BH
  94         select ARCH_INLINE_SPIN_UNLOCK
  95         select ARCH_INLINE_SPIN_UNLOCK_BH
  96         select ARCH_INLINE_SPIN_UNLOCK_IRQ
  97         select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
  98         select ARCH_INLINE_WRITE_LOCK
  99         select ARCH_INLINE_WRITE_LOCK_BH
 100         select ARCH_INLINE_WRITE_LOCK_IRQ
 101         select ARCH_INLINE_WRITE_LOCK_IRQSAVE
 102         select ARCH_INLINE_WRITE_TRYLOCK
 103         select ARCH_INLINE_WRITE_UNLOCK
 104         select ARCH_INLINE_WRITE_UNLOCK_BH
 105         select ARCH_INLINE_WRITE_UNLOCK_IRQ
 106         select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
 107         select ARCH_SAVE_PAGE_KEYS if HIBERNATION
 108         select ARCH_SUPPORTS_ATOMIC_RMW
 109         select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
 110         select ARCH_SUPPORTS_NUMA_BALANCING
 111         select ARCH_USE_BUILTIN_BSWAP
 112         select ARCH_USE_CMPXCHG_LOCKREF
 113         select ARCH_WANTS_DYNAMIC_TASK_STRUCT
 114         select ARCH_WANTS_PROT_NUMA_PROT_NONE
 115         select ARCH_WANTS_UBSAN_NO_NULL
 116         select ARCH_WANT_IPC_PARSE_VERSION
 117         select BUILDTIME_EXTABLE_SORT
 118         select CLONE_BACKWARDS2
 119         select DYNAMIC_FTRACE if FUNCTION_TRACER
 120         select GENERIC_CLOCKEVENTS
 121         select GENERIC_CPU_AUTOPROBE
 122         select GENERIC_CPU_DEVICES if !SMP
 123         select GENERIC_FIND_FIRST_BIT
 124         select GENERIC_SMP_IDLE_THREAD
 125         select GENERIC_TIME_VSYSCALL
 126         select HAVE_ALIGNED_STRUCT_PAGE if SLUB
 127         select HAVE_ARCH_AUDITSYSCALL
 128         select HAVE_ARCH_JUMP_LABEL
 129         select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
 130         select HAVE_ARCH_SECCOMP_FILTER
 131         select HAVE_ARCH_SOFT_DIRTY
 132         select HAVE_ARCH_TRACEHOOK
 133         select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 134         select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
 135         select HAVE_CMPXCHG_DOUBLE
 136         select HAVE_CMPXCHG_LOCAL
 137         select HAVE_COPY_THREAD_TLS
 138         select HAVE_DEBUG_KMEMLEAK
 139         select HAVE_DMA_API_DEBUG
 140         select HAVE_DMA_CONTIGUOUS
 141         select DMA_NOOP_OPS
 142         select HAVE_DYNAMIC_FTRACE
 143         select HAVE_DYNAMIC_FTRACE_WITH_REGS
 144         select HAVE_EFFICIENT_UNALIGNED_ACCESS
 145         select HAVE_EXIT_THREAD
 146         select HAVE_FTRACE_MCOUNT_RECORD
 147         select HAVE_FUNCTION_GRAPH_TRACER
 148         select HAVE_FUNCTION_TRACER
 149         select HAVE_FUTEX_CMPXCHG if FUTEX
 150         select HAVE_KERNEL_BZIP2
 151         select HAVE_KERNEL_GZIP
 152         select HAVE_KERNEL_LZ4
 153         select HAVE_KERNEL_LZMA
 154         select HAVE_KERNEL_LZO
 155         select HAVE_KERNEL_XZ
 156         select HAVE_KPROBES
 157         select HAVE_KRETPROBES
 158         select HAVE_KVM
 159         select HAVE_LIVEPATCH
 160         select HAVE_MEMBLOCK
 161         select HAVE_MEMBLOCK_NODE_MAP
 162         select HAVE_MEMBLOCK_PHYS_MAP
 163         select HAVE_MOD_ARCH_SPECIFIC
 164         select HAVE_OPROFILE
 165         select HAVE_PERF_EVENTS
 166         select HAVE_REGS_AND_STACK_ACCESS_API
 167         select HAVE_SYSCALL_TRACEPOINTS
 168         select HAVE_VIRT_CPU_ACCOUNTING
 169         select MODULES_USE_ELF_RELA
 170         select NO_BOOTMEM
 171         select OLD_SIGACTION
 172         select OLD_SIGSUSPEND3
 173         select SPARSE_IRQ
 174         select SYSCTL_EXCEPTION_TRACE
 175         select THREAD_INFO_IN_TASK
 176         select TTY
 177         select VIRT_CPU_ACCOUNTING
 178         select ARCH_HAS_SCALED_CPUTIME
 179         select VIRT_TO_BUS
 180         select HAVE_NMI
 181
 182
 183 config SCHED_OMIT_FRAME_POINTER
 184         def_bool y
 185
 186 config PGTABLE_LEVELS
 187         int
 188         default 5
 189
 190 source "init/Kconfig"
 191
 192 source "kernel/Kconfig.freezer"
 193
 194 source "kernel/livepatch/Kconfig"
 195
 196 menu "Processor type and features"
 197
 198 config HAVE_MARCH_Z900_FEATURES
 199         def_bool n
 200
 201 config HAVE_MARCH_Z990_FEATURES
 202         def_bool n
 203         select HAVE_MARCH_Z900_FEATURES
 204
 205 config HAVE_MARCH_Z9_109_FEATURES
 206         def_bool n
 207         select HAVE_MARCH_Z990_FEATURES
 208
 209 config HAVE_MARCH_Z10_FEATURES
 210         def_bool n
 211         select HAVE_MARCH_Z9_109_FEATURES
 212
 213 config HAVE_MARCH_Z196_FEATURES
 214         def_bool n
 215         select HAVE_MARCH_Z10_FEATURES
 216
 217 config HAVE_MARCH_ZEC12_FEATURES
 218         def_bool n
 219         select HAVE_MARCH_Z196_FEATURES
 220
 221 config HAVE_MARCH_Z13_FEATURES
 222         def_bool n
 223         select HAVE_MARCH_ZEC12_FEATURES
 224
 225 choice
 226         prompt "Processor type"
 227         default MARCH_Z196
 228
 229 config MARCH_Z900
 230         bool "IBM zSeries model z800 and z900"
 231         select HAVE_MARCH_Z900_FEATURES
 232         help
 233           Select this to enable optimizations for model z800/z900 (2064 and
 234           2066 series). This will enable some optimizations that are not
 235           available on older ESA/390 (31 Bit) only CPUs.
 236
 237 config MARCH_Z990
 238         bool "IBM zSeries model z890 and z990"
 239         select HAVE_MARCH_Z990_FEATURES
 240         help
 241           Select this to enable optimizations for model z890/z990 (2084 and
 242           2086 series). The kernel will be slightly faster but will not work
 243           on older machines.
 244
 245 config MARCH_Z9_109
 246         bool "IBM System z9"
 247         select HAVE_MARCH_Z9_109_FEATURES
 248         help
 249           Select this to enable optimizations for IBM System z9 (2094 and
 250           2096 series). The kernel will be slightly faster but will not work
 251           on older machines.
 252
 253 config MARCH_Z10
 254         bool "IBM System z10"
 255         select HAVE_MARCH_Z10_FEATURES
 256         help
 257           Select this to enable optimizations for IBM System z10 (2097 and
 258           2098 series). The kernel will be slightly faster but will not work
 259           on older machines.
 260
 261 config MARCH_Z196
 262         bool "IBM zEnterprise 114 and 196"
 263         select HAVE_MARCH_Z196_FEATURES
 264         help
 265           Select this to enable optimizations for IBM zEnterprise 114 and 196
 266           (2818 and 2817 series). The kernel will be slightly faster but will
 267           not work on older machines.
 268
 269 config MARCH_ZEC12
 270         bool "IBM zBC12 and zEC12"
 271         select HAVE_MARCH_ZEC12_FEATURES
 272         help
 273           Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
 274           2827 series). The kernel will be slightly faster but will not work on
 275           older machines.
 276
 277 config MARCH_Z13
 278         bool "IBM z13s and z13"
 279         select HAVE_MARCH_Z13_FEATURES
 280         help
 281           Select this to enable optimizations for IBM z13s and z13 (2965 and
 282           2964 series). The kernel will be slightly faster but will not work on
 283           older machines.
 284
 285 endchoice
 286
 287 config MARCH_Z900_TUNE
 288         def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
 289
 290 config MARCH_Z990_TUNE
 291         def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
 292
 293 config MARCH_Z9_109_TUNE
 294         def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
 295
 296 config MARCH_Z10_TUNE
 297         def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
 298
 299 config MARCH_Z196_TUNE
 300         def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
 301
 302 config MARCH_ZEC12_TUNE
 303         def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
 304
 305 config MARCH_Z13_TUNE
 306         def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
 307
 308 choice
 309         prompt "Tune code generation"
 310         default TUNE_DEFAULT
 311         help
 312           Cause the compiler to tune (-mtune) the generated code for a machine.
 313           This will make the code run faster on the selected machine but
 314           somewhat slower on other machines.
 315           This option only changes how the compiler emits instructions, not the
 316           selection of instructions itself, so the resulting kernel will run on
 317           all other machines.
 318
 319 config TUNE_DEFAULT
 320         bool "Default"
 321         help
 322           Tune the generated code for the target processor for which the kernel
 323           will be compiled.
 324
 325 config TUNE_Z900
 326         bool "IBM zSeries model z800 and z900"
 327
 328 config TUNE_Z990
 329         bool "IBM zSeries model z890 and z990"
 330
 331 config TUNE_Z9_109
 332         bool "IBM System z9"
 333
 334 config TUNE_Z10
 335         bool "IBM System z10"
 336
 337 config TUNE_Z196
 338         bool "IBM zEnterprise 114 and 196"
 339
 340 config TUNE_ZEC12
 341         bool "IBM zBC12 and zEC12"
 342
 343 config TUNE_Z13
 344         bool "IBM z13"
 345
 346 endchoice
 347
 348 config 64BIT
 349         def_bool y
 350
 351 config COMPAT
 352         def_bool y
 353         prompt "Kernel support for 31 bit emulation"
 354         select COMPAT_BINFMT_ELF if BINFMT_ELF
 355         select ARCH_WANT_OLD_COMPAT_IPC
 356         select COMPAT_OLD_SIGACTION
 357         depends on MULTIUSER
 358         help
 359           Select this option if you want to enable your system kernel to
 360           handle system-calls from ELF binaries for 31 bit ESA.  This option
 361           (and some other stuff like libraries and such) is needed for
 362           executing 31 bit applications.  It is safe to say "Y".
 363
 364 config SYSVIPC_COMPAT
 365         def_bool y if COMPAT && SYSVIPC
 366
 367 config SMP
 368         def_bool y
 369         prompt "Symmetric multi-processing support"
 370         ---help---
 371           This enables support for systems with more than one CPU. If you have
 372           a system with only one CPU, like most personal computers, say N. If
 373           you have a system with more than one CPU, say Y.
 374
 375           If you say N here, the kernel will run on uni- and multiprocessor
 376           machines, but will use only one CPU of a multiprocessor machine. If
 377           you say Y here, the kernel will run on many, but not all,
 378           uniprocessor machines. On a uniprocessor machine, the kernel
 379           will run faster if you say N here.
 380
 381           See also the SMP-HOWTO available at
 382           <http://www.tldp.org/docs.html#howto>.
 383
 384           Even if you don't know what to do here, say Y.
 385
 386 config NR_CPUS
 387         int "Maximum number of CPUs (2-512)"
 388         range 2 512
 389         depends on SMP
 390         default "64"
 391         help
 392           This allows you to specify the maximum number of CPUs which this
 393           kernel will support. The maximum supported value is 512 and the
 394           minimum value which makes sense is 2.
 395
 396           This is purely to save memory - each supported CPU adds
 397           approximately sixteen kilobytes to the kernel image.
 398
 399 config HOTPLUG_CPU
 400         def_bool y
 401         prompt "Support for hot-pluggable CPUs"
 402         depends on SMP
 403         help
 404           Say Y here to be able to turn CPUs off and on. CPUs
 405           can be controlled through /sys/devices/system/cpu/cpu#.
 406           Say N if you want to disable CPU hotplug.
 407
 408 # Some NUMA nodes have memory ranges that span
 409 # other nodes.  Even though a pfn is valid and
 410 # between a node's start and end pfns, it may not
 411 # reside on that node.  See memmap_init_zone()
 412 # for details. <- They meant memory holes!
 413 config NODES_SPAN_OTHER_NODES
 414         def_bool NUMA
 415
 416 config NUMA
 417         bool "NUMA support"
 418         depends on SMP && SCHED_TOPOLOGY
 419         default n
 420         help
 421           Enable NUMA support
 422
 423           This option adds NUMA support to the kernel.
 424
 425           An operation mode can be selected by appending
 426           numa=<method> to the kernel command line.
 427
 428           The default behaviour is identical to appending numa=plain to
 429           the command line. This will create just one node with all
 430           available memory and all CPUs in it.
 431
 432 config NODES_SHIFT
 433         int "Maximum NUMA nodes (as a power of 2)"
 434         range 1 10
 435         depends on NUMA
 436         default "4"
 437         help
 438           Specify the maximum number of NUMA nodes available on the target
 439           system. Increases memory reserved to accommodate various tables.
 440
 441 menu "Select NUMA modes"
 442         depends on NUMA
 443
 444 config NUMA_EMU
 445         bool "NUMA emulation"
 446         default y
 447         help
 448           Numa emulation mode will split the available system memory into
 449           equal chunks which then are distributed over the configured number
 450           of nodes in a round-robin manner.
 451
 452           The number of fake nodes is limited by the number of available memory
 453           chunks (i.e. memory size / fake size) and the number of supported
 454           nodes in the kernel.
 455
 456           The CPUs are assigned to the nodes in a way that partially respects
 457           the original machine topology (if supported by the machine).
 458           Fair distribution of the CPUs is not guaranteed.
 459
 460 config EMU_SIZE
 461         hex "NUMA emulation memory chunk size"
 462         default 0x10000000
 463         range 0x400000 0x100000000
 464         depends on NUMA_EMU
 465         help
 466           Select the default size by which the memory is chopped and then
 467           assigned to emulated NUMA nodes.
 468
 469           This can be overridden by specifying
 470
 471           emu_size=<n>
 472
 473           on the kernel command line where also suffixes K, M, G, and T are
 474           supported.
 475
 476 endmenu
 477
 478 config SCHED_SMT
 479         def_bool n
 480
 481 config SCHED_MC
 482         def_bool n
 483
 484 config SCHED_BOOK
 485         def_bool n
 486
 487 config SCHED_DRAWER
 488         def_bool n
 489
 490 config SCHED_TOPOLOGY
 491         def_bool y
 492         prompt "Topology scheduler support"
 493         depends on SMP
 494         select SCHED_SMT
 495         select SCHED_MC
 496         select SCHED_BOOK
 497         select SCHED_DRAWER
 498         help
 499           Topology scheduler support improves the CPU scheduler's decision
 500           making when dealing with machines that have multi-threading,
 501           multiple cores or multiple books.
 502
 503 source kernel/Kconfig.preempt
 504
 505 source kernel/Kconfig.hz
 506
 507 config ARCH_RANDOM
 508         def_bool y
 509         prompt "s390 architectural random number generation API"
 510         help
 511           Enable the s390 architectural random number generation API
 512           to provide random data for all consumers within the Linux
 513           kernel.
 514
 515           When enabled the arch_random_* functions declared in linux/random.h
 516           are implemented. The implementation is based on the s390 CPACF
 517           instruction subfunction TRNG which provides a real true random
 518           number generator.
 519
 520           If unsure, say Y.
 521
 522 config KERNEL_NOBP
 523        def_bool n
 524        prompt "Enable modified branch prediction for the kernel by default"
 525        help
 526          If this option is selected the kernel will switch to a modified
 527          branch prediction mode if the firmware interface is available.
 528          The modified branch prediction mode improves the behaviour in
 529          regard to speculative execution.
 530
 531          With the option enabled the kernel parameter "nobp=0" or "nospec"
 532          can be used to run the kernel in the normal branch prediction mode.
 533
 534          With the option disabled the modified branch prediction mode is
 535          enabled with the "nobp=1" kernel parameter.
 536
 537          If unsure, say N.
 538
 539 endmenu
 540
 541 menu "Memory setup"
 542
 543 config ARCH_SPARSEMEM_ENABLE
 544         def_bool y
 545         select SPARSEMEM_VMEMMAP_ENABLE
 546         select SPARSEMEM_VMEMMAP
 547
 548 config ARCH_SPARSEMEM_DEFAULT
 549         def_bool y
 550
 551 config ARCH_SELECT_MEMORY_MODEL
 552         def_bool y
 553
 554 config ARCH_ENABLE_MEMORY_HOTPLUG
 555         def_bool y if SPARSEMEM
 556
 557 config ARCH_ENABLE_MEMORY_HOTREMOVE
 558         def_bool y
 559
 560 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
 561         def_bool y
 562
 563 config FORCE_MAX_ZONEORDER
 564         int
 565         default "9"
 566
 567 source "mm/Kconfig"
 568
 569 config MAX_PHYSMEM_BITS
 570         int "Maximum size of supported physical memory in bits (42-53)"
 571         range 42 53
 572         default "46"
 573         help
 574           This option specifies the maximum supported size of physical memory
 575           in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
 576           Increasing the number of bits also increases the kernel image size.
 577           By default 46 bits (64TB) are supported.
 578
 579 config PACK_STACK
 580         def_bool y
 581         prompt "Pack kernel stack"
 582         help
 583           This option enables the compiler option -mkernel-backchain if it
 584           is available. If the option is available the compiler supports
 585           the new stack layout which dramatically reduces the minimum stack
 586           frame size. With an old compiler a non-leaf function needs a
 587           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 588           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 589           and 24 byte on 64 bit.
 590
 591           Say Y if you are unsure.
 592
 593 config CHECK_STACK
 594         def_bool y
 595         prompt "Detect kernel stack overflow"
 596         help
 597           This option enables the compiler option -mstack-guard and
 598           -mstack-size if they are available. If the compiler supports them
 599           it will emit additional code to each function prolog to trigger
 600           an illegal operation if the kernel stack is about to overflow.
 601
 602           Say N if you are unsure.
 603
 604 config STACK_GUARD
 605         int "Size of the guard area (128-1024)"
 606         range 128 1024
 607         depends on CHECK_STACK
 608         default "256"
 609         help
 610           This allows you to specify the size of the guard area at the lower
 611           end of the kernel stack. If the kernel stack points into the guard
 612           area on function entry an illegal operation is triggered. The size
 613           needs to be a power of 2. Please keep in mind that the size of an
 614           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 615           The minimum size for the stack guard should be 256 for 31 bit and
 616           512 for 64 bit.
 617
 618 config WARN_DYNAMIC_STACK
 619         def_bool n
 620         prompt "Emit compiler warnings for function with dynamic stack usage"
 621         help
 622           This option enables the compiler option -mwarn-dynamicstack. If the
 623           compiler supports this options generates warnings for functions
 624           that dynamically allocate stack space using alloca.
 625
 626           Say N if you are unsure.
 627
 628 endmenu
 629
 630 menu "I/O subsystem"
 631
 632 config QDIO
 633         def_tristate y
 634         prompt "QDIO support"
 635         ---help---
 636           This driver provides the Queued Direct I/O base support for
 637           IBM System z.
 638
 639           To compile this driver as a module, choose M here: the
 640           module will be called qdio.
 641
 642           If unsure, say Y.
 643
 644 menuconfig PCI
 645         bool "PCI support"
 646         select PCI_MSI
 647         select IOMMU_SUPPORT
 648         help
 649           Enable PCI support.
 650
 651 if PCI
 652
 653 config PCI_NR_FUNCTIONS
 654         int "Maximum number of PCI functions (1-4096)"
 655         range 1 4096
 656         default "128"
 657         help
 658           This allows you to specify the maximum number of PCI functions which
 659           this kernel will support.
 660
 661 source "drivers/pci/Kconfig"
 662
 663 endif   # PCI
 664
 665 config PCI_DOMAINS
 666         def_bool PCI
 667
 668 config HAS_IOMEM
 669         def_bool PCI
 670
 671 config IOMMU_HELPER
 672         def_bool PCI
 673
 674 config NEED_SG_DMA_LENGTH
 675         def_bool PCI
 676
 677 config NEED_DMA_MAP_STATE
 678         def_bool PCI
 679
 680 config CHSC_SCH
 681         def_tristate m
 682         prompt "Support for CHSC subchannels"
 683         help
 684           This driver allows usage of CHSC subchannels. A CHSC subchannel
 685           is usually present on LPAR only.
 686           The driver creates a device /dev/chsc, which may be used to
 687           obtain I/O configuration information about the machine and
 688           to issue asynchronous chsc commands (DANGEROUS).
 689           You will usually only want to use this interface on a special
 690           LPAR designated for system management.
 691
 692           To compile this driver as a module, choose M here: the
 693           module will be called chsc_sch.
 694
 695           If unsure, say N.
 696
 697 config SCM_BUS
 698         def_bool y
 699         prompt "SCM bus driver"
 700         help
 701           Bus driver for Storage Class Memory.
 702
 703 config EADM_SCH
 704         def_tristate m
 705         prompt "Support for EADM subchannels"
 706         depends on SCM_BUS
 707         help
 708           This driver allows usage of EADM subchannels. EADM subchannels act
 709           as a communication vehicle for SCM increments.
 710
 711           To compile this driver as a module, choose M here: the
 712           module will be called eadm_sch.
 713
 714 config VFIO_CCW
 715         def_tristate n
 716         prompt "Support for VFIO-CCW subchannels"
 717         depends on S390_CCW_IOMMU && VFIO_MDEV
 718         help
 719           This driver allows usage of I/O subchannels via VFIO-CCW.
 720
 721           To compile this driver as a module, choose M here: the
 722           module will be called vfio_ccw.
 723
 724 endmenu
 725
 726 menu "Dump support"
 727
 728 config CRASH_DUMP
 729         bool "kernel crash dumps"
 730         depends on SMP
 731         select KEXEC
 732         help
 733           Generate crash dump after being started by kexec.
 734           Crash dump kernels are loaded in the main kernel with kexec-tools
 735           into a specially reserved region and then later executed after
 736           a crash by kdump/kexec.
 737           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 738           This option also enables s390 zfcpdump.
 739           See also <file:Documentation/s390/zfcpdump.txt>
 740
 741 endmenu
 742
 743 menu "Executable file formats / Emulations"
 744
 745 source "fs/Kconfig.binfmt"
 746
 747 config SECCOMP
 748         def_bool y
 749         prompt "Enable seccomp to safely compute untrusted bytecode"
 750         depends on PROC_FS
 751         help
 752           This kernel feature is useful for number crunching applications
 753           that may need to compute untrusted bytecode during their
 754           execution. By using pipes or other transports made available to
 755           the process as file descriptors supporting the read/write
 756           syscalls, it's possible to isolate those applications in
 757           their own address space using seccomp. Once seccomp is
 758           enabled via /proc/<pid>/seccomp, it cannot be disabled
 759           and the task is only allowed to execute a few safe syscalls
 760           defined by each seccomp mode.
 761
 762           If unsure, say Y.
 763
 764 endmenu
 765
 766 menu "Power Management"
 767
 768 config ARCH_HIBERNATION_POSSIBLE
 769         def_bool y
 770
 771 source "kernel/power/Kconfig"
 772
 773 endmenu
 774
 775 source "net/Kconfig"
 776
 777 config PCMCIA
 778         def_bool n
 779
 780 config CCW
 781         def_bool y
 782
 783 source "drivers/Kconfig"
 784
 785 source "fs/Kconfig"
 786
 787 source "arch/s390/Kconfig.debug"
 788
 789 source "security/Kconfig"
 790
 791 source "crypto/Kconfig"
 792
 793 source "lib/Kconfig"
 794
 795 menu "Virtualization"
 796
 797 config PFAULT
 798         def_bool y
 799         prompt "Pseudo page fault support"
 800         help
 801           Select this option, if you want to use PFAULT pseudo page fault
 802           handling under VM. If running native or in LPAR, this option
 803           has no effect. If your VM does not support PFAULT, PAGEEX
 804           pseudo page fault handling will be used.
 805           Note that VM 4.2 supports PFAULT but has a bug in its
 806           implementation that causes some problems.
 807           Everybody who wants to run Linux under VM != VM4.2 should select
 808           this option.
 809
 810 config SHARED_KERNEL
 811         bool "VM shared kernel support"
 812         depends on !JUMP_LABEL
 813         help
 814           Select this option, if you want to share the text segment of the
 815           Linux kernel between different VM guests. This reduces memory
 816           usage with lots of guests but greatly increases kernel size.
 817           Also if a kernel was IPL'ed from a shared segment the kexec system
 818           call will not work.
 819           You should only select this option if you know what you are
 820           doing and want to exploit this feature.
 821
 822 config CMM
 823         def_tristate n
 824         prompt "Cooperative memory management"
 825         help
 826           Select this option, if you want to enable the kernel interface
 827           to reduce the memory size of the system. This is accomplished
 828           by allocating pages of memory and put them "on hold". This only
 829           makes sense for a system running under VM where the unused pages
 830           will be reused by VM for other guest systems. The interface
 831           allows an external monitor to balance memory of many systems.
 832           Everybody who wants to run Linux under VM should select this
 833           option.
 834
 835 config CMM_IUCV
 836         def_bool y
 837         prompt "IUCV special message interface to cooperative memory management"
 838         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 839         help
 840           Select this option to enable the special message interface to
 841           the cooperative memory management.
 842
 843 config APPLDATA_BASE
 844         def_bool n
 845         prompt "Linux - VM Monitor Stream, base infrastructure"
 846         depends on PROC_FS
 847         help
 848           This provides a kernel interface for creating and updating z/VM APPLDATA
 849           monitor records. The monitor records are updated at certain time
 850           intervals, once the timer is started.
 851           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 852           i.e. enables or disables monitoring on the Linux side.
 853           A custom interval value (in seconds) can be written to
 854           /proc/appldata/interval.
 855
 856           Defaults are 60 seconds interval and timer off.
 857           The /proc entries can also be read from, showing the current settings.
 858
 859 config APPLDATA_MEM
 860         def_tristate m
 861         prompt "Monitor memory management statistics"
 862         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 863         help
 864           This provides memory management related data to the Linux - VM Monitor
 865           Stream, like paging/swapping rate, memory utilisation, etc.
 866           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 867           APPLDATA monitor record, i.e. enables or disables monitoring this record
 868           on the z/VM side.
 869
 870           Default is disabled.
 871           The /proc entry can also be read from, showing the current settings.
 872
 873           This can also be compiled as a module, which will be called
 874           appldata_mem.o.
 875
 876 config APPLDATA_OS
 877         def_tristate m
 878         prompt "Monitor OS statistics"
 879         depends on APPLDATA_BASE
 880         help
 881           This provides OS related data to the Linux - VM Monitor Stream, like
 882           CPU utilisation, etc.
 883           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 884           APPLDATA monitor record, i.e. enables or disables monitoring this record
 885           on the z/VM side.
 886
 887           Default is disabled.
 888           This can also be compiled as a module, which will be called
 889           appldata_os.o.
 890
 891 config APPLDATA_NET_SUM
 892         def_tristate m
 893         prompt "Monitor overall network statistics"
 894         depends on APPLDATA_BASE && NET
 895         help
 896           This provides network related data to the Linux - VM Monitor Stream,
 897           currently there is only a total sum of network I/O statistics, no
 898           per-interface data.
 899           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 900           APPLDATA monitor record, i.e. enables or disables monitoring this record
 901           on the z/VM side.
 902
 903           Default is disabled.
 904           This can also be compiled as a module, which will be called
 905           appldata_net_sum.o.
 906
 907 config S390_HYPFS_FS
 908         def_bool y
 909         prompt "s390 hypervisor file system support"
 910         select SYS_HYPERVISOR
 911         help
 912           This is a virtual file system intended to provide accounting
 913           information in an s390 hypervisor environment.
 914
 915 source "arch/s390/kvm/Kconfig"
 916
 917 config S390_GUEST
 918         def_bool y
 919         prompt "s390 support for virtio devices"
 920         select TTY
 921         select VIRTUALIZATION
 922         select VIRTIO
 923         select VIRTIO_CONSOLE
 924         help
 925           Enabling this option adds support for virtio based paravirtual device
 926           drivers on s390.
 927
 928           Select this option if you want to run the kernel as a guest under
 929           the KVM hypervisor.
 930
 931 config S390_GUEST_OLD_TRANSPORT
 932         def_bool y
 933         prompt "Guest support for old s390 virtio transport (DEPRECATED)"
 934         depends on S390_GUEST
 935         help
 936           Enable this option to add support for the old s390-virtio
 937           transport (i.e. virtio devices NOT based on virtio-ccw). This
 938           type of virtio devices is only available on the experimental
 939           kuli userspace or with old (< 2.6) qemu. If you are running
 940           with a modern version of qemu (which supports virtio-ccw since
 941           1.4 and uses it by default since version 2.4), you probably won't
 942           need this.
 943
 944 endmenu
 945
 946 config KMSG_IDS
 947         def_bool y
 948         prompt "Kernel message numbers"
 949         help
 950           Select this option if you want to include a message number to the
 951           prefix for kernel messages issued by the s390 architecture and
 952           driver code. See "Documentation/s390/kmsg.txt" for more details.