1# 2# For a description of the syntax of this configuration file, 3# see Documentation/kbuild/kconfig-language.txt. 4# 5 6config SCHED_MC 7 def_bool y 8 depends on SMP 9 10config MMU 11 def_bool y 12 13config ZONE_DMA 14 def_bool y 15 depends on 64BIT 16 17config LOCKDEP_SUPPORT 18 def_bool y 19 20config STACKTRACE_SUPPORT 21 def_bool y 22 23config HAVE_LATENCYTOP_SUPPORT 24 def_bool y 25 26config RWSEM_GENERIC_SPINLOCK 27 bool 28 29config RWSEM_XCHGADD_ALGORITHM 30 def_bool y 31 32config ARCH_HAS_ILOG2_U32 33 bool 34 default n 35 36config ARCH_HAS_ILOG2_U64 37 bool 38 default n 39 40config GENERIC_HWEIGHT 41 def_bool y 42 43config GENERIC_TIME 44 def_bool y 45 46config GENERIC_CLOCKEVENTS 47 def_bool y 48 49config GENERIC_BUG 50 bool 51 depends on BUG 52 default y 53 54config NO_IOMEM 55 def_bool y 56 57config NO_DMA 58 def_bool y 59 60config GENERIC_LOCKBREAK 61 bool 62 default y 63 depends on SMP && PREEMPT 64 65config PGSTE 66 bool 67 default y if KVM 68 69mainmenu "Linux Kernel Configuration" 70 71config S390 72 def_bool y 73 select HAVE_OPROFILE 74 select HAVE_KPROBES 75 select HAVE_KRETPROBES 76 select HAVE_KVM if 64BIT 77 select HAVE_ARCH_TRACEHOOK 78 79source "init/Kconfig" 80 81source "kernel/Kconfig.freezer" 82 83menu "Base setup" 84 85comment "Processor type and features" 86 87source "kernel/time/Kconfig" 88 89config 64BIT 90 bool "64 bit kernel" 91 help 92 Select this option if you have a 64 bit IBM zSeries machine 93 and want to use the 64 bit addressing mode. 94 95config 32BIT 96 bool 97 default y if !64BIT 98 99config SMP 100 bool "Symmetric multi-processing support" 101 ---help--- 102 This enables support for systems with more than one CPU. If you have 103 a system with only one CPU, like most personal computers, say N. If 104 you have a system with more than one CPU, say Y. 105 106 If you say N here, the kernel will run on single and multiprocessor 107 machines, but will use only one CPU of a multiprocessor machine. If 108 you say Y here, the kernel will run on many, but not all, 109 singleprocessor machines. On a singleprocessor machine, the kernel 110 will run faster if you say N here. 111 112 See also the SMP-HOWTO available at 113 <http://www.tldp.org/docs.html#howto>. 114 115 Even if you don't know what to do here, say Y. 116 117config NR_CPUS 118 int "Maximum number of CPUs (2-64)" 119 range 2 64 120 depends on SMP 121 default "32" if !64BIT 122 default "64" if 64BIT 123 help 124 This allows you to specify the maximum number of CPUs which this 125 kernel will support. The maximum supported value is 64 and the 126 minimum value which makes sense is 2. 127 128 This is purely to save memory - each supported CPU adds 129 approximately sixteen kilobytes to the kernel image. 130 131config HOTPLUG_CPU 132 bool "Support for hot-pluggable CPUs" 133 depends on SMP 134 select HOTPLUG 135 default n 136 help 137 Say Y here to be able to turn CPUs off and on. CPUs 138 can be controlled through /sys/devices/system/cpu/cpu#. 139 Say N if you want to disable CPU hotplug. 140 141config MATHEMU 142 bool "IEEE FPU emulation" 143 depends on MARCH_G5 144 help 145 This option is required for IEEE compliant floating point arithmetic 146 on older S/390 machines. Say Y unless you know your machine doesn't 147 need this. 148 149config COMPAT 150 bool "Kernel support for 31 bit emulation" 151 depends on 64BIT 152 select COMPAT_BINFMT_ELF 153 help 154 Select this option if you want to enable your system kernel to 155 handle system-calls from ELF binaries for 31 bit ESA. This option 156 (and some other stuff like libraries and such) is needed for 157 executing 31 bit applications. It is safe to say "Y". 158 159config SYSVIPC_COMPAT 160 bool 161 depends on COMPAT && SYSVIPC 162 default y 163 164config AUDIT_ARCH 165 bool 166 default y 167 168config S390_SWITCH_AMODE 169 bool "Switch kernel/user addressing modes" 170 help 171 This option allows to switch the addressing modes of kernel and user 172 space. The kernel parameter switch_amode=on will enable this feature, 173 default is disabled. Enabling this (via kernel parameter) on machines 174 earlier than IBM System z9-109 EC/BC will reduce system performance. 175 176 Note that this option will also be selected by selecting the execute 177 protection option below. Enabling the execute protection via the 178 noexec kernel parameter will also switch the addressing modes, 179 independent of the switch_amode kernel parameter. 180 181 182config S390_EXEC_PROTECT 183 bool "Data execute protection" 184 select S390_SWITCH_AMODE 185 help 186 This option allows to enable a buffer overflow protection for user 187 space programs and it also selects the addressing mode option above. 188 The kernel parameter noexec=on will enable this feature and also 189 switch the addressing modes, default is disabled. Enabling this (via 190 kernel parameter) on machines earlier than IBM System z9-109 EC/BC 191 will reduce system performance. 192 193comment "Code generation options" 194 195choice 196 prompt "Processor type" 197 default MARCH_G5 198 199config MARCH_G5 200 bool "S/390 model G5 and G6" 201 depends on !64BIT 202 help 203 Select this to build a 31 bit kernel that works 204 on all S/390 and zSeries machines. 205 206config MARCH_Z900 207 bool "IBM eServer zSeries model z800 and z900" 208 help 209 Select this to optimize for zSeries machines. This 210 will enable some optimizations that are not available 211 on older 31 bit only CPUs. 212 213config MARCH_Z990 214 bool "IBM eServer zSeries model z890 and z990" 215 help 216 Select this enable optimizations for model z890/z990. 217 This will be slightly faster but does not work on 218 older machines such as the z900. 219 220config MARCH_Z9_109 221 bool "IBM System z9" 222 help 223 Select this to enable optimizations for IBM System z9-109, IBM 224 System z9 Enterprise Class (z9 EC), and IBM System z9 Business 225 Class (z9 BC). The kernel will be slightly faster but will not 226 work on older machines such as the z990, z890, z900, and z800. 227 228endchoice 229 230config PACK_STACK 231 bool "Pack kernel stack" 232 help 233 This option enables the compiler option -mkernel-backchain if it 234 is available. If the option is available the compiler supports 235 the new stack layout which dramatically reduces the minimum stack 236 frame size. With an old compiler a non-leaf function needs a 237 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With 238 -mkernel-backchain the minimum size drops to 16 byte on 31 bit 239 and 24 byte on 64 bit. 240 241 Say Y if you are unsure. 242 243config SMALL_STACK 244 bool "Use 8kb for kernel stack instead of 16kb" 245 depends on PACK_STACK && 64BIT && !LOCKDEP 246 help 247 If you say Y here and the compiler supports the -mkernel-backchain 248 option the kernel will use a smaller kernel stack size. The reduced 249 size is 8kb instead of 16kb. This allows to run more threads on a 250 system and reduces the pressure on the memory management for higher 251 order page allocations. 252 253 Say N if you are unsure. 254 255config CHECK_STACK 256 bool "Detect kernel stack overflow" 257 help 258 This option enables the compiler option -mstack-guard and 259 -mstack-size if they are available. If the compiler supports them 260 it will emit additional code to each function prolog to trigger 261 an illegal operation if the kernel stack is about to overflow. 262 263 Say N if you are unsure. 264 265config STACK_GUARD 266 int "Size of the guard area (128-1024)" 267 range 128 1024 268 depends on CHECK_STACK 269 default "256" 270 help 271 This allows you to specify the size of the guard area at the lower 272 end of the kernel stack. If the kernel stack points into the guard 273 area on function entry an illegal operation is triggered. The size 274 needs to be a power of 2. Please keep in mind that the size of an 275 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 276 The minimum size for the stack guard should be 256 for 31 bit and 277 512 for 64 bit. 278 279config WARN_STACK 280 bool "Emit compiler warnings for function with broken stack usage" 281 help 282 This option enables the compiler options -mwarn-framesize and 283 -mwarn-dynamicstack. If the compiler supports these options it 284 will generate warnings for function which either use alloca or 285 create a stack frame bigger then CONFIG_WARN_STACK_SIZE. 286 287 Say N if you are unsure. 288 289config WARN_STACK_SIZE 290 int "Maximum frame size considered safe (128-2048)" 291 range 128 2048 292 depends on WARN_STACK 293 default "2048" 294 help 295 This allows you to specify the maximum frame size a function may 296 have without the compiler complaining about it. 297 298config ARCH_POPULATES_NODE_MAP 299 def_bool y 300 301comment "Kernel preemption" 302 303source "kernel/Kconfig.preempt" 304 305config ARCH_SPARSEMEM_ENABLE 306 def_bool y 307 select SPARSEMEM_VMEMMAP_ENABLE 308 select SPARSEMEM_VMEMMAP 309 select SPARSEMEM_STATIC if !64BIT 310 311config ARCH_SPARSEMEM_DEFAULT 312 def_bool y 313 314config ARCH_SELECT_MEMORY_MODEL 315 def_bool y 316 317config ARCH_ENABLE_MEMORY_HOTPLUG 318 def_bool y 319 depends on SPARSEMEM 320 321config ARCH_ENABLE_MEMORY_HOTREMOVE 322 def_bool y 323 324source "mm/Kconfig" 325 326comment "I/O subsystem configuration" 327 328config MACHCHK_WARNING 329 bool "Process warning machine checks" 330 help 331 Select this option if you want the machine check handler on IBM S/390 or 332 zSeries to process warning machine checks (e.g. on power failures). 333 If unsure, say "Y". 334 335config QDIO 336 tristate "QDIO support" 337 ---help--- 338 This driver provides the Queued Direct I/O base support for 339 IBM System z. 340 341 To compile this driver as a module, choose M here: the 342 module will be called qdio. 343 344 If unsure, say Y. 345 346config QDIO_DEBUG 347 bool "Extended debugging information" 348 depends on QDIO 349 help 350 Say Y here to get extended debugging output in 351 /sys/kernel/debug/s390dbf/qdio... 352 Warning: this option reduces the performance of the QDIO module. 353 354 If unsure, say N. 355 356config CHSC_SCH 357 tristate "Support for CHSC subchannels" 358 help 359 This driver allows usage of CHSC subchannels. A CHSC subchannel 360 is usually present on LPAR only. 361 The driver creates a device /dev/chsc, which may be used to 362 obtain I/O configuration information about the machine and 363 to issue asynchronous chsc commands (DANGEROUS). 364 You will usually only want to use this interface on a special 365 LPAR designated for system management. 366 367 To compile this driver as a module, choose M here: the 368 module will be called chsc_sch. 369 370 If unsure, say N. 371 372comment "Misc" 373 374config IPL 375 bool "Builtin IPL record support" 376 help 377 If you want to use the produced kernel to IPL directly from a 378 device, you have to merge a bootsector specific to the device 379 into the first bytes of the kernel. You will have to select the 380 IPL device. 381 382choice 383 prompt "IPL method generated into head.S" 384 depends on IPL 385 default IPL_VM 386 help 387 Select "tape" if you want to IPL the image from a Tape. 388 389 Select "vm_reader" if you are running under VM/ESA and want 390 to IPL the image from the emulated card reader. 391 392config IPL_TAPE 393 bool "tape" 394 395config IPL_VM 396 bool "vm_reader" 397 398endchoice 399 400source "fs/Kconfig.binfmt" 401 402config FORCE_MAX_ZONEORDER 403 int 404 default "9" 405 406config PROCESS_DEBUG 407 bool "Show crashed user process info" 408 help 409 Say Y to print all process fault locations to the console. This is 410 a debugging option; you probably do not want to set it unless you 411 are an S390 port maintainer. 412 413config PFAULT 414 bool "Pseudo page fault support" 415 help 416 Select this option, if you want to use PFAULT pseudo page fault 417 handling under VM. If running native or in LPAR, this option 418 has no effect. If your VM does not support PFAULT, PAGEEX 419 pseudo page fault handling will be used. 420 Note that VM 4.2 supports PFAULT but has a bug in its 421 implementation that causes some problems. 422 Everybody who wants to run Linux under VM != VM4.2 should select 423 this option. 424 425config SHARED_KERNEL 426 bool "VM shared kernel support" 427 help 428 Select this option, if you want to share the text segment of the 429 Linux kernel between different VM guests. This reduces memory 430 usage with lots of guests but greatly increases kernel size. 431 Also if a kernel was IPL'ed from a shared segment the kexec system 432 call will not work. 433 You should only select this option if you know what you are 434 doing and want to exploit this feature. 435 436config CMM 437 tristate "Cooperative memory management" 438 help 439 Select this option, if you want to enable the kernel interface 440 to reduce the memory size of the system. This is accomplished 441 by allocating pages of memory and put them "on hold". This only 442 makes sense for a system running under VM where the unused pages 443 will be reused by VM for other guest systems. The interface 444 allows an external monitor to balance memory of many systems. 445 Everybody who wants to run Linux under VM should select this 446 option. 447 448config CMM_PROC 449 bool "/proc interface to cooperative memory management" 450 depends on CMM 451 help 452 Select this option to enable the /proc interface to the 453 cooperative memory management. 454 455config CMM_IUCV 456 bool "IUCV special message interface to cooperative memory management" 457 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 458 help 459 Select this option to enable the special message interface to 460 the cooperative memory management. 461 462config PAGE_STATES 463 bool "Unused page notification" 464 help 465 This enables the notification of unused pages to the 466 hypervisor. The ESSA instruction is used to do the states 467 changes between a page that has content and the unused state. 468 469config VIRT_TIMER 470 bool "Virtual CPU timer support" 471 help 472 This provides a kernel interface for virtual CPU timers. 473 Default is disabled. 474 475config VIRT_CPU_ACCOUNTING 476 bool "Base user process accounting on virtual cpu timer" 477 depends on VIRT_TIMER 478 help 479 Select this option to use CPU timer deltas to do user 480 process accounting. 481 482config APPLDATA_BASE 483 bool "Linux - VM Monitor Stream, base infrastructure" 484 depends on PROC_FS && VIRT_TIMER=y 485 help 486 This provides a kernel interface for creating and updating z/VM APPLDATA 487 monitor records. The monitor records are updated at certain time 488 intervals, once the timer is started. 489 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 490 i.e. enables or disables monitoring on the Linux side. 491 A custom interval value (in seconds) can be written to 492 /proc/appldata/interval. 493 494 Defaults are 60 seconds interval and timer off. 495 The /proc entries can also be read from, showing the current settings. 496 497config APPLDATA_MEM 498 tristate "Monitor memory management statistics" 499 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 500 help 501 This provides memory management related data to the Linux - VM Monitor 502 Stream, like paging/swapping rate, memory utilisation, etc. 503 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 504 APPLDATA monitor record, i.e. enables or disables monitoring this record 505 on the z/VM side. 506 507 Default is disabled. 508 The /proc entry can also be read from, showing the current settings. 509 510 This can also be compiled as a module, which will be called 511 appldata_mem.o. 512 513config APPLDATA_OS 514 tristate "Monitor OS statistics" 515 depends on APPLDATA_BASE 516 help 517 This provides OS related data to the Linux - VM Monitor Stream, like 518 CPU utilisation, etc. 519 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 520 APPLDATA monitor record, i.e. enables or disables monitoring this record 521 on the z/VM side. 522 523 Default is disabled. 524 This can also be compiled as a module, which will be called 525 appldata_os.o. 526 527config APPLDATA_NET_SUM 528 tristate "Monitor overall network statistics" 529 depends on APPLDATA_BASE 530 help 531 This provides network related data to the Linux - VM Monitor Stream, 532 currently there is only a total sum of network I/O statistics, no 533 per-interface data. 534 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 535 APPLDATA monitor record, i.e. enables or disables monitoring this record 536 on the z/VM side. 537 538 Default is disabled. 539 This can also be compiled as a module, which will be called 540 appldata_net_sum.o. 541 542source kernel/Kconfig.hz 543 544config S390_HYPFS_FS 545 bool "s390 hypervisor file system support" 546 select SYS_HYPERVISOR 547 default y 548 help 549 This is a virtual file system intended to provide accounting 550 information in an s390 hypervisor environment. 551 552config KEXEC 553 bool "kexec system call" 554 help 555 kexec is a system call that implements the ability to shutdown your 556 current kernel, and to start another kernel. It is like a reboot 557 but is independent of hardware/microcode support. 558 559config ZFCPDUMP 560 tristate "zfcpdump support" 561 select SMP 562 default n 563 help 564 Select this option if you want to build an zfcpdump enabled kernel. 565 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this. 566 567config S390_GUEST 568bool "s390 guest support for KVM (EXPERIMENTAL)" 569 depends on 64BIT && EXPERIMENTAL 570 select VIRTIO 571 select VIRTIO_RING 572 select VIRTIO_CONSOLE 573 help 574 Select this option if you want to run the kernel as a guest under 575 the KVM hypervisor. This will add detection for KVM as well as a 576 virtio transport. If KVM is detected, the virtio console will be 577 the default console. 578endmenu 579 580source "net/Kconfig" 581 582config PCMCIA 583 def_bool n 584 585config CCW 586 def_bool y 587 588source "drivers/Kconfig" 589 590source "fs/Kconfig" 591 592source "arch/s390/Kconfig.debug" 593 594source "security/Kconfig" 595 596source "crypto/Kconfig" 597 598source "lib/Kconfig" 599 600source "arch/s390/kvm/Kconfig" 601