Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
[linux-2.6-block.git] / arch / s390 / Kconfig
CommitLineData
b2441318 1# SPDX-License-Identifier: GPL-2.0
1da177e4 2config MMU
61d48c2c 3 def_bool y
1da177e4 4
66701b14 5config ZONE_DMA
69dbb2f7 6 def_bool y
66701b14 7
2fd92273
HC
8config CPU_BIG_ENDIAN
9 def_bool y
10
2b105ff9 11config LOCKDEP_SUPPORT
61d48c2c 12 def_bool y
2b105ff9 13
5bdc9b44 14config STACKTRACE_SUPPORT
61d48c2c 15 def_bool y
5bdc9b44 16
1da177e4
LT
17config RWSEM_GENERIC_SPINLOCK
18 bool
19
20config RWSEM_XCHGADD_ALGORITHM
61d48c2c 21 def_bool y
1da177e4 22
f0d1b0b3 23config ARCH_HAS_ILOG2_U32
6f9a3c33 24 def_bool n
f0d1b0b3
DH
25
26config ARCH_HAS_ILOG2_U64
6f9a3c33 27 def_bool n
f0d1b0b3 28
7e33db4e 29config GENERIC_HWEIGHT
61d48c2c 30 def_bool y
7e33db4e 31
c0007f1a 32config GENERIC_BUG
6f9a3c33 33 def_bool y if BUG
c0007f1a 34
52499f40
HC
35config GENERIC_BUG_RELATIVE_POINTERS
36 def_bool y
37
b6b40c53 38config GENERIC_LOCKBREAK
6f9a3c33 39 def_bool y if SMP && PREEMPT
b6b40c53 40
402b0862 41config PGSTE
6f9a3c33 42 def_bool y if KVM
402b0862 43
6a11f75b
AM
44config ARCH_SUPPORTS_DEBUG_PAGEALLOC
45 def_bool y
46
843c48fd
JG
47config AUDIT_ARCH
48 def_bool y
49
ce816fa8 50config NO_IOPORT_MAP
c8717a3d
JG
51 def_bool y
52
53config PCI_QUIRKS
54 def_bool n
55
2a0a5b22 56config ARCH_SUPPORTS_UPROBES
5a79859a 57 def_bool y
2a0a5b22 58
5e785963
VG
59config KASAN_SHADOW_OFFSET
60 hex
61 depends on KASAN
5dff0381 62 default 0x18000000000000 if KASAN_S390_4_LEVEL_PAGING
5e785963
VG
63 default 0x30000000000
64
347a8dc3 65config S390
61d48c2c 66 def_bool y
23fefe11 67 select ARCH_BINFMT_ELF_STATE
21266be9 68 select ARCH_HAS_DEVMEM_IS_ALLOWED
2b68f6ca 69 select ARCH_HAS_ELF_RANDOMIZE
79962038 70 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 71 select ARCH_HAS_GCOV_PROFILE_ALL
e1073d1e 72 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
907fa061 73 select ARCH_HAS_KCOV
3010a5ea 74 select ARCH_HAS_PTE_SPECIAL
d2852a22 75 select ARCH_HAS_SET_MEMORY
ad21fc4f
LA
76 select ARCH_HAS_STRICT_KERNEL_RWX
77 select ARCH_HAS_STRICT_MODULE_RWX
aa0d6e70 78 select ARCH_HAS_SYSCALL_WRAPPER
c42d8c7d 79 select ARCH_HAS_UBSAN_SANITIZE_ALL
0e0d04a8 80 select ARCH_HAVE_NMI_SAFE_CMPXCHG
6beb0009
TG
81 select ARCH_INLINE_READ_LOCK
82 select ARCH_INLINE_READ_LOCK_BH
83 select ARCH_INLINE_READ_LOCK_IRQ
84 select ARCH_INLINE_READ_LOCK_IRQSAVE
0e0d04a8 85 select ARCH_INLINE_READ_TRYLOCK
6beb0009
TG
86 select ARCH_INLINE_READ_UNLOCK
87 select ARCH_INLINE_READ_UNLOCK_BH
88 select ARCH_INLINE_READ_UNLOCK_IRQ
89 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
0e0d04a8
HC
90 select ARCH_INLINE_SPIN_LOCK
91 select ARCH_INLINE_SPIN_LOCK_BH
92 select ARCH_INLINE_SPIN_LOCK_IRQ
93 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
94 select ARCH_INLINE_SPIN_TRYLOCK
95 select ARCH_INLINE_SPIN_TRYLOCK_BH
96 select ARCH_INLINE_SPIN_UNLOCK
97 select ARCH_INLINE_SPIN_UNLOCK_BH
98 select ARCH_INLINE_SPIN_UNLOCK_IRQ
99 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
6beb0009
TG
100 select ARCH_INLINE_WRITE_LOCK
101 select ARCH_INLINE_WRITE_LOCK_BH
102 select ARCH_INLINE_WRITE_LOCK_IRQ
103 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
0e0d04a8 104 select ARCH_INLINE_WRITE_TRYLOCK
6beb0009
TG
105 select ARCH_INLINE_WRITE_UNLOCK
106 select ARCH_INLINE_WRITE_UNLOCK_BH
107 select ARCH_INLINE_WRITE_UNLOCK_IRQ
108 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
0e0d04a8 109 select ARCH_SAVE_PAGE_KEYS if HIBERNATION
36e7fdaa 110 select ARCH_SUPPORTS_ATOMIC_RMW
a763bc8b 111 select ARCH_SUPPORTS_NUMA_BALANCING
295d8fa9 112 select ARCH_USE_BUILTIN_BSWAP
efc1d23b 113 select ARCH_USE_CMPXCHG_LOCKREF
3f6813b9 114 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
c1d7e01d 115 select ARCH_WANT_IPC_PARSE_VERSION
0e0d04a8
HC
116 select BUILDTIME_EXTABLE_SORT
117 select CLONE_BACKWARDS2
5d6a0163 118 select DYNAMIC_FTRACE if FUNCTION_TRACER
0e0d04a8 119 select GENERIC_CLOCKEVENTS
8f00b3e2 120 select GENERIC_CPU_AUTOPROBE
0e0d04a8 121 select GENERIC_CPU_DEVICES if !SMP
d424986f 122 select GENERIC_CPU_VULNERABILITIES
746479cd 123 select GENERIC_FIND_FIRST_BIT
e80e7813 124 select GENERIC_SMP_IDLE_THREAD
79c74ecb 125 select GENERIC_TIME_VSYSCALL
0e0d04a8 126 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
7a017721 127 select HAVE_ARCH_AUDITSYSCALL
5a79859a 128 select HAVE_ARCH_JUMP_LABEL
13ddb52c 129 select HAVE_ARCH_JUMP_LABEL_RELATIVE
42db5ed8 130 select HAVE_ARCH_KASAN
fff7fb0b 131 select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
c63cb468 132 select HAVE_ARCH_SECCOMP_FILTER
5614dd92 133 select HAVE_ARCH_SOFT_DIRTY
0e0d04a8 134 select HAVE_ARCH_TRACEHOOK
5a79859a 135 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
ce3dc447 136 select HAVE_ARCH_VMAP_STACK
6077776b 137 select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
0e0d04a8
HC
138 select HAVE_CMPXCHG_DOUBLE
139 select HAVE_CMPXCHG_LOCAL
f50c0e63 140 select HAVE_COPY_THREAD_TLS
0e0d04a8 141 select HAVE_DEBUG_KMEMLEAK
e1231b0e 142 select HAVE_DMA_CONTIGUOUS
5a79859a
HC
143 select HAVE_DYNAMIC_FTRACE
144 select HAVE_DYNAMIC_FTRACE_WITH_REGS
9078a549 145 select HAVE_EFFICIENT_UNALIGNED_ACCESS
d983c89c 146 select HAVE_FENTRY
0e0d04a8 147 select HAVE_FTRACE_MCOUNT_RECORD
5a79859a
HC
148 select HAVE_FUNCTION_GRAPH_TRACER
149 select HAVE_FUNCTION_TRACER
03b8c7b6 150 select HAVE_FUTEX_CMPXCHG if FUTEX
bc00b3ec 151 select HAVE_GCC_PLUGINS
0e0d04a8
HC
152 select HAVE_KERNEL_BZIP2
153 select HAVE_KERNEL_GZIP
8e2872ce 154 select HAVE_KERNEL_LZ4
0e0d04a8
HC
155 select HAVE_KERNEL_LZMA
156 select HAVE_KERNEL_LZO
89b5202e 157 select HAVE_KERNEL_UNCOMPRESSED
0e0d04a8
HC
158 select HAVE_KERNEL_XZ
159 select HAVE_KPROBES
160 select HAVE_KRETPROBES
5a79859a 161 select HAVE_KVM
21042d43 162 select HAVE_LIVEPATCH
c33eff60
HC
163 select HAVE_PERF_REGS
164 select HAVE_PERF_USER_STACK_DUMP
0e0d04a8 165 select HAVE_MEMBLOCK_NODE_MAP
50be6345 166 select HAVE_MEMBLOCK_PHYS_MAP
786d35d4 167 select HAVE_MOD_ARCH_SPECIFIC
d983c89c 168 select HAVE_NOP_MCOUNT
0e0d04a8 169 select HAVE_OPROFILE
eb01d42a 170 select HAVE_PCI
0e0d04a8
HC
171 select HAVE_PERF_EVENTS
172 select HAVE_REGS_AND_STACK_ACCESS_API
9d6d99e3 173 select HAVE_RSEQ
0e0d04a8 174 select HAVE_SYSCALL_TRACEPOINTS
0e0d04a8 175 select HAVE_VIRT_CPU_ACCOUNTING
eb01d42a
CH
176 select IOMMU_HELPER if PCI
177 select IOMMU_SUPPORT if PCI
786d35d4 178 select MODULES_USE_ELF_RELA
eb01d42a
CH
179 select NEED_DMA_MAP_STATE if PCI
180 select NEED_SG_DMA_LENGTH if PCI
7eddd99c 181 select OLD_SIGACTION
93bead43 182 select OLD_SIGSUSPEND3
2eac9c2d 183 select PCI_DOMAINS if PCI
eb01d42a 184 select PCI_MSI if PCI
bb98f396 185 select SPARSE_IRQ
0e0d04a8 186 select SYSCTL_EXCEPTION_TRACE
d5c352cd 187 select THREAD_INFO_IN_TASK
0563416b 188 select TTY
0e0d04a8 189 select VIRT_CPU_ACCOUNTING
40565b5a 190 select ARCH_HAS_SCALED_CPUTIME
93bead43 191 select VIRT_TO_BUS
42a0bb3f 192 select HAVE_NMI
3a368f74 193
1da177e4 194
fca3e357 195config SCHED_OMIT_FRAME_POINTER
6f9a3c33 196 def_bool y
fca3e357 197
c81956c9
KS
198config PGTABLE_LEVELS
199 int
1aea9b3f 200 default 5
c81956c9 201
21042d43
JS
202source "kernel/livepatch/Kconfig"
203
843c48fd
JG
204menu "Processor type and features"
205
206config HAVE_MARCH_Z900_FEATURES
207 def_bool n
208
209config HAVE_MARCH_Z990_FEATURES
210 def_bool n
211 select HAVE_MARCH_Z900_FEATURES
212
213config HAVE_MARCH_Z9_109_FEATURES
214 def_bool n
215 select HAVE_MARCH_Z990_FEATURES
216
217config HAVE_MARCH_Z10_FEATURES
218 def_bool n
219 select HAVE_MARCH_Z9_109_FEATURES
220
221config HAVE_MARCH_Z196_FEATURES
222 def_bool n
223 select HAVE_MARCH_Z10_FEATURES
224
991c1505
HC
225config HAVE_MARCH_ZEC12_FEATURES
226 def_bool n
227 select HAVE_MARCH_Z196_FEATURES
228
f8b2dcbd
MS
229config HAVE_MARCH_Z13_FEATURES
230 def_bool n
231 select HAVE_MARCH_ZEC12_FEATURES
232
6997c323
MS
233config HAVE_MARCH_Z14_FEATURES
234 def_bool n
235 select HAVE_MARCH_Z13_FEATURES
236
843c48fd
JG
237choice
238 prompt "Processor type"
7072276e 239 default MARCH_Z196
1da177e4 240
843c48fd
JG
241config MARCH_Z900
242 bool "IBM zSeries model z800 and z900"
5a79859a 243 select HAVE_MARCH_Z900_FEATURES
843c48fd
JG
244 help
245 Select this to enable optimizations for model z800/z900 (2064 and
246 2066 series). This will enable some optimizations that are not
247 available on older ESA/390 (31 Bit) only CPUs.
248
249config MARCH_Z990
250 bool "IBM zSeries model z890 and z990"
5a79859a 251 select HAVE_MARCH_Z990_FEATURES
843c48fd
JG
252 help
253 Select this to enable optimizations for model z890/z990 (2084 and
254 2086 series). The kernel will be slightly faster but will not work
255 on older machines.
256
257config MARCH_Z9_109
258 bool "IBM System z9"
5a79859a 259 select HAVE_MARCH_Z9_109_FEATURES
843c48fd
JG
260 help
261 Select this to enable optimizations for IBM System z9 (2094 and
262 2096 series). The kernel will be slightly faster but will not work
263 on older machines.
264
265config MARCH_Z10
266 bool "IBM System z10"
5a79859a 267 select HAVE_MARCH_Z10_FEATURES
843c48fd
JG
268 help
269 Select this to enable optimizations for IBM System z10 (2097 and
270 2098 series). The kernel will be slightly faster but will not work
271 on older machines.
272
273config MARCH_Z196
274 bool "IBM zEnterprise 114 and 196"
5a79859a 275 select HAVE_MARCH_Z196_FEATURES
843c48fd
JG
276 help
277 Select this to enable optimizations for IBM zEnterprise 114 and 196
278 (2818 and 2817 series). The kernel will be slightly faster but will
279 not work on older machines.
1da177e4 280
991c1505 281config MARCH_ZEC12
59471227 282 bool "IBM zBC12 and zEC12"
5a79859a 283 select HAVE_MARCH_ZEC12_FEATURES
991c1505 284 help
59471227
HC
285 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
286 2827 series). The kernel will be slightly faster but will not work on
287 older machines.
991c1505 288
f8b2dcbd 289config MARCH_Z13
bb3aa614 290 bool "IBM z13s and z13"
5a79859a 291 select HAVE_MARCH_Z13_FEATURES
f8b2dcbd 292 help
bb3aa614
HC
293 Select this to enable optimizations for IBM z13s and z13 (2965 and
294 2964 series). The kernel will be slightly faster but will not work on
295 older machines.
f8b2dcbd 296
6997c323 297config MARCH_Z14
451239eb 298 bool "IBM z14 ZR1 and z14"
6997c323
MS
299 select HAVE_MARCH_Z14_FEATURES
300 help
451239eb
HC
301 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
302 and 3906 series). The kernel will be slightly faster but will not
303 work on older machines.
6997c323 304
843c48fd 305endchoice
1da177e4 306
1db9e051
HC
307config MARCH_Z900_TUNE
308 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
309
310config MARCH_Z990_TUNE
311 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
312
313config MARCH_Z9_109_TUNE
314 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
315
316config MARCH_Z10_TUNE
317 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
318
319config MARCH_Z196_TUNE
320 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
321
322config MARCH_ZEC12_TUNE
323 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
324
f8b2dcbd
MS
325config MARCH_Z13_TUNE
326 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
327
6997c323
MS
328config MARCH_Z14_TUNE
329 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
330
1db9e051
HC
331choice
332 prompt "Tune code generation"
333 default TUNE_DEFAULT
334 help
335 Cause the compiler to tune (-mtune) the generated code for a machine.
336 This will make the code run faster on the selected machine but
337 somewhat slower on other machines.
338 This option only changes how the compiler emits instructions, not the
339 selection of instructions itself, so the resulting kernel will run on
340 all other machines.
341
342config TUNE_DEFAULT
343 bool "Default"
344 help
345 Tune the generated code for the target processor for which the kernel
346 will be compiled.
347
1db9e051
HC
348config TUNE_Z900
349 bool "IBM zSeries model z800 and z900"
350
351config TUNE_Z990
352 bool "IBM zSeries model z890 and z990"
353
354config TUNE_Z9_109
355 bool "IBM System z9"
356
357config TUNE_Z10
358 bool "IBM System z10"
359
360config TUNE_Z196
361 bool "IBM zEnterprise 114 and 196"
362
363config TUNE_ZEC12
364 bool "IBM zBC12 and zEC12"
365
f8b2dcbd
MS
366config TUNE_Z13
367 bool "IBM z13"
368
6997c323
MS
369config TUNE_Z14
370 bool "IBM z14"
371
1db9e051
HC
372endchoice
373
347a8dc3 374config 64BIT
6f9a3c33 375 def_bool y
d9f7a745 376
843c48fd
JG
377config COMPAT
378 def_bool y
379 prompt "Kernel support for 31 bit emulation"
843c48fd
JG
380 select COMPAT_BINFMT_ELF if BINFMT_ELF
381 select ARCH_WANT_OLD_COMPAT_IPC
7eddd99c 382 select COMPAT_OLD_SIGACTION
fef747ba 383 select HAVE_UID16
2813893f 384 depends on MULTIUSER
843c48fd
JG
385 help
386 Select this option if you want to enable your system kernel to
387 handle system-calls from ELF binaries for 31 bit ESA. This option
388 (and some other stuff like libraries and such) is needed for
389 executing 31 bit applications. It is safe to say "Y".
390
391config SYSVIPC_COMPAT
392 def_bool y if COMPAT && SYSVIPC
393
1da177e4 394config SMP
6f9a3c33
MS
395 def_bool y
396 prompt "Symmetric multi-processing support"
1da177e4
LT
397 ---help---
398 This enables support for systems with more than one CPU. If you have
399 a system with only one CPU, like most personal computers, say N. If
400 you have a system with more than one CPU, say Y.
401
4a474157 402 If you say N here, the kernel will run on uni- and multiprocessor
1da177e4
LT
403 machines, but will use only one CPU of a multiprocessor machine. If
404 you say Y here, the kernel will run on many, but not all,
4a474157 405 uniprocessor machines. On a uniprocessor machine, the kernel
1da177e4
LT
406 will run faster if you say N here.
407
03502faa
AB
408 See also the SMP-HOWTO available at
409 <http://www.tldp.org/docs.html#howto>.
1da177e4
LT
410
411 Even if you don't know what to do here, say Y.
412
413config NR_CPUS
5c75a0da
HC
414 int "Maximum number of CPUs (2-512)"
415 range 2 512
1da177e4 416 depends on SMP
5a79859a 417 default "64"
1da177e4
LT
418 help
419 This allows you to specify the maximum number of CPUs which this
5c75a0da 420 kernel will support. The maximum supported value is 512 and the
1da177e4
LT
421 minimum value which makes sense is 2.
422
423 This is purely to save memory - each supported CPU adds
424 approximately sixteen kilobytes to the kernel image.
425
426config HOTPLUG_CPU
6f9a3c33
MS
427 def_bool y
428 prompt "Support for hot-pluggable CPUs"
1da177e4 429 depends on SMP
1da177e4
LT
430 help
431 Say Y here to be able to turn CPUs off and on. CPUs
432 can be controlled through /sys/devices/system/cpu/cpu#.
433 Say N if you want to disable CPU hotplug.
434
3a368f74
PH
435# Some NUMA nodes have memory ranges that span
436# other nodes. Even though a pfn is valid and
437# between a node's start and end pfns, it may not
438# reside on that node. See memmap_init_zone()
439# for details. <- They meant memory holes!
440config NODES_SPAN_OTHER_NODES
441 def_bool NUMA
442
443config NUMA
444 bool "NUMA support"
c095a949 445 depends on SMP && SCHED_TOPOLOGY
3a368f74
PH
446 default n
447 help
448 Enable NUMA support
449
450 This option adds NUMA support to the kernel.
451
452 An operation mode can be selected by appending
453 numa=<method> to the kernel command line.
454
455 The default behaviour is identical to appending numa=plain to
456 the command line. This will create just one node with all
457 available memory and all CPUs in it.
458
459config NODES_SHIFT
460 int "Maximum NUMA nodes (as a power of 2)"
461 range 1 10
462 depends on NUMA
463 default "4"
464 help
465 Specify the maximum number of NUMA nodes available on the target
466 system. Increases memory reserved to accommodate various tables.
467
c29a7baf
MH
468menu "Select NUMA modes"
469 depends on NUMA
470
471config NUMA_EMU
472 bool "NUMA emulation"
473 default y
474 help
475 Numa emulation mode will split the available system memory into
476 equal chunks which then are distributed over the configured number
477 of nodes in a round-robin manner.
478
479 The number of fake nodes is limited by the number of available memory
480 chunks (i.e. memory size / fake size) and the number of supported
481 nodes in the kernel.
482
483 The CPUs are assigned to the nodes in a way that partially respects
484 the original machine topology (if supported by the machine).
485 Fair distribution of the CPUs is not guaranteed.
486
487config EMU_SIZE
488 hex "NUMA emulation memory chunk size"
489 default 0x10000000
490 range 0x400000 0x100000000
491 depends on NUMA_EMU
492 help
493 Select the default size by which the memory is chopped and then
494 assigned to emulated NUMA nodes.
495
496 This can be overridden by specifying
497
498 emu_size=<n>
499
500 on the kernel command line where also suffixes K, M, G, and T are
501 supported.
502
503endmenu
9236b4dd
HC
504
505config SCHED_SMT
506 def_bool n
c29a7baf 507
8d11e021 508config SCHED_MC
83a24e32 509 def_bool n
8d11e021 510
4cb14bc8 511config SCHED_BOOK
10ad34bc
MS
512 def_bool n
513
adac0f1e
HC
514config SCHED_DRAWER
515 def_bool n
516
10ad34bc 517config SCHED_TOPOLOGY
6f9a3c33 518 def_bool y
10ad34bc 519 prompt "Topology scheduler support"
83a24e32 520 depends on SMP
10ad34bc 521 select SCHED_SMT
83a24e32 522 select SCHED_MC
10ad34bc 523 select SCHED_BOOK
adac0f1e 524 select SCHED_DRAWER
4cb14bc8 525 help
10ad34bc
MS
526 Topology scheduler support improves the CPU scheduler's decision
527 making when dealing with machines that have multi-threading,
528 multiple cores or multiple books.
4cb14bc8 529
8636a1f9 530source "kernel/Kconfig.hz"
1da177e4 531
bdea9f6f
PR
532config KEXEC
533 def_bool y
534 select KEXEC_CORE
535
536config KEXEC_FILE
537 bool "kexec file based system call"
538 select KEXEC_CORE
539 select BUILD_BIN2C
540 depends on CRYPTO
541 depends on CRYPTO_SHA256
542 depends on CRYPTO_SHA256_S390
543 help
544 Enable the kexec file based system call. In contrast to the normal
545 kexec system call this system call takes file descriptors for the
546 kernel and initramfs as arguments.
547
548config ARCH_HAS_KEXEC_PURGATORY
549 def_bool y
550 depends on KEXEC_FILE
551
4c637cd8
HF
552config ARCH_RANDOM
553 def_bool y
554 prompt "s390 architectural random number generation API"
555 help
556 Enable the s390 architectural random number generation API
557 to provide random data for all consumers within the Linux
558 kernel.
559
560 When enabled the arch_random_* functions declared in linux/random.h
561 are implemented. The implementation is based on the s390 CPACF
562 instruction subfunction TRNG which provides a real true random
563 number generator.
564
565 If unsure, say Y.
566
d768bd89
MS
567config KERNEL_NOBP
568 def_bool n
569 prompt "Enable modified branch prediction for the kernel by default"
570 help
571 If this option is selected the kernel will switch to a modified
572 branch prediction mode if the firmware interface is available.
573 The modified branch prediction mode improves the behaviour in
574 regard to speculative execution.
575
576 With the option enabled the kernel parameter "nobp=0" or "nospec"
577 can be used to run the kernel in the normal branch prediction mode.
578
579 With the option disabled the modified branch prediction mode is
580 enabled with the "nobp=1" kernel parameter.
581
582 If unsure, say N.
583
f19fbd5e
MS
584config EXPOLINE
585 def_bool n
586 prompt "Avoid speculative indirect branches in the kernel"
587 help
588 Compile the kernel with the expoline compiler options to guard
589 against kernel-to-user data leaks by avoiding speculative indirect
590 branches.
591 Requires a compiler with -mindirect-branch=thunk support for full
592 protection. The kernel may run slower.
593
594 If unsure, say N.
595
596choice
597 prompt "Expoline default"
598 depends on EXPOLINE
599 default EXPOLINE_FULL
600
601config EXPOLINE_OFF
602 bool "spectre_v2=off"
603
6e179d64 604config EXPOLINE_AUTO
f19fbd5e
MS
605 bool "spectre_v2=auto"
606
607config EXPOLINE_FULL
608 bool "spectre_v2=on"
609
610endchoice
611
843c48fd 612endmenu
1da177e4 613
843c48fd 614menu "Memory setup"
1d057720 615
843c48fd 616config ARCH_SPARSEMEM_ENABLE
6f9a3c33 617 def_bool y
843c48fd
JG
618 select SPARSEMEM_VMEMMAP_ENABLE
619 select SPARSEMEM_VMEMMAP
e65e1fc2 620
843c48fd
JG
621config ARCH_SPARSEMEM_DEFAULT
622 def_bool y
1da177e4 623
843c48fd
JG
624config ARCH_SELECT_MEMORY_MODEL
625 def_bool y
1da177e4 626
843c48fd
JG
627config ARCH_ENABLE_MEMORY_HOTPLUG
628 def_bool y if SPARSEMEM
0efa4703 629
843c48fd
JG
630config ARCH_ENABLE_MEMORY_HOTREMOVE
631 def_bool y
e37f50e1 632
ec66ad66
MS
633config ARCH_ENABLE_SPLIT_PMD_PTLOCK
634 def_bool y
ec66ad66 635
843c48fd
JG
636config FORCE_MAX_ZONEORDER
637 int
638 default "9"
f861e405 639
b8402b95
HC
640config MAX_PHYSMEM_BITS
641 int "Maximum size of supported physical memory in bits (42-53)"
642 range 42 53
643 default "46"
644 help
645 This option specifies the maximum supported size of physical memory
646 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
647 Increasing the number of bits also increases the kernel image size.
648 By default 46 bits (64TB) are supported.
649
1da177e4 650config PACK_STACK
6f9a3c33
MS
651 def_bool y
652 prompt "Pack kernel stack"
1da177e4
LT
653 help
654 This option enables the compiler option -mkernel-backchain if it
655 is available. If the option is available the compiler supports
656 the new stack layout which dramatically reduces the minimum stack
657 frame size. With an old compiler a non-leaf function needs a
658 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
659 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
660 and 24 byte on 64 bit.
661
662 Say Y if you are unsure.
663
1da177e4 664config CHECK_STACK
6f9a3c33 665 def_bool y
ce3dc447 666 depends on !VMAP_STACK
6f9a3c33 667 prompt "Detect kernel stack overflow"
1da177e4
LT
668 help
669 This option enables the compiler option -mstack-guard and
670 -mstack-size if they are available. If the compiler supports them
671 it will emit additional code to each function prolog to trigger
672 an illegal operation if the kernel stack is about to overflow.
673
674 Say N if you are unsure.
675
676config STACK_GUARD
677 int "Size of the guard area (128-1024)"
678 range 128 1024
679 depends on CHECK_STACK
680 default "256"
681 help
682 This allows you to specify the size of the guard area at the lower
683 end of the kernel stack. If the kernel stack points into the guard
684 area on function entry an illegal operation is triggered. The size
685 needs to be a power of 2. Please keep in mind that the size of an
686 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
687 The minimum size for the stack guard should be 256 for 31 bit and
688 512 for 64 bit.
689
2c190da4 690config WARN_DYNAMIC_STACK
6f9a3c33 691 def_bool n
2c190da4 692 prompt "Emit compiler warnings for function with dynamic stack usage"
1da177e4 693 help
2c190da4
JG
694 This option enables the compiler option -mwarn-dynamicstack. If the
695 compiler supports this options generates warnings for functions
696 that dynamically allocate stack space using alloca.
1da177e4
LT
697
698 Say N if you are unsure.
699
843c48fd 700endmenu
3f22ab27 701
843c48fd 702menu "I/O subsystem"
1da177e4 703
1da177e4 704config QDIO
6f9a3c33
MS
705 def_tristate y
706 prompt "QDIO support"
1da177e4 707 ---help---
8129ee16 708 This driver provides the Queued Direct I/O base support for
efca13bc 709 IBM System z.
1da177e4
LT
710
711 To compile this driver as a module, choose M here: the
712 module will be called qdio.
713
714 If unsure, say Y.
715
c8717a3d
JG
716if PCI
717
718config PCI_NR_FUNCTIONS
719 int "Maximum number of PCI functions (1-4096)"
720 range 1 4096
b18601b0 721 default "128"
c8717a3d
JG
722 help
723 This allows you to specify the maximum number of PCI functions which
724 this kernel will support.
725
c8717a3d
JG
726endif # PCI
727
c8717a3d
JG
728config HAS_IOMEM
729 def_bool PCI
730
9d92a7e1 731config CHSC_SCH
d9c11b1e 732 def_tristate m
6f9a3c33 733 prompt "Support for CHSC subchannels"
9d92a7e1
CH
734 help
735 This driver allows usage of CHSC subchannels. A CHSC subchannel
736 is usually present on LPAR only.
737 The driver creates a device /dev/chsc, which may be used to
738 obtain I/O configuration information about the machine and
739 to issue asynchronous chsc commands (DANGEROUS).
740 You will usually only want to use this interface on a special
741 LPAR designated for system management.
742
743 To compile this driver as a module, choose M here: the
744 module will be called chsc_sch.
745
746 If unsure, say N.
747
1d1c8f78
SO
748config SCM_BUS
749 def_bool y
1d1c8f78
SO
750 prompt "SCM bus driver"
751 help
752 Bus driver for Storage Class Memory.
753
eadb86ab
SO
754config EADM_SCH
755 def_tristate m
756 prompt "Support for EADM subchannels"
757 depends on SCM_BUS
758 help
759 This driver allows usage of EADM subchannels. EADM subchannels act
760 as a communication vehicle for SCM increments.
761
762 To compile this driver as a module, choose M here: the
763 module will be called eadm_sch.
764
63f1934d
DJS
765config VFIO_CCW
766 def_tristate n
767 prompt "Support for VFIO-CCW subchannels"
84cd8fc4 768 depends on S390_CCW_IOMMU && VFIO_MDEV
63f1934d
DJS
769 help
770 This driver allows usage of I/O subchannels via VFIO-CCW.
771
772 To compile this driver as a module, choose M here: the
773 module will be called vfio_ccw.
774
1fde5734
TK
775config VFIO_AP
776 def_tristate n
777 prompt "VFIO support for AP devices"
778 depends on S390_AP_IOMMU && VFIO_MDEV_DEVICE && KVM
779 help
780 This driver grants access to Adjunct Processor (AP) devices
781 via the VFIO mediated device interface.
782
783 To compile this driver as a module, choose M here: the module
784 will be called vfio_ap.
785
843c48fd
JG
786endmenu
787
788menu "Dump support"
789
790config CRASH_DUMP
791 bool "kernel crash dumps"
5a79859a 792 depends on SMP
843c48fd
JG
793 select KEXEC
794 help
795 Generate crash dump after being started by kexec.
796 Crash dump kernels are loaded in the main kernel with kexec-tools
797 into a specially reserved region and then later executed after
798 a crash by kdump/kexec.
843c48fd 799 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
bf28a597
MH
800 This option also enables s390 zfcpdump.
801 See also <file:Documentation/s390/zfcpdump.txt>
843c48fd
JG
802
803endmenu
804
843c48fd
JG
805config SECCOMP
806 def_bool y
807 prompt "Enable seccomp to safely compute untrusted bytecode"
808 depends on PROC_FS
809 help
810 This kernel feature is useful for number crunching applications
811 that may need to compute untrusted bytecode during their
812 execution. By using pipes or other transports made available to
813 the process as file descriptors supporting the read/write
814 syscalls, it's possible to isolate those applications in
815 their own address space using seccomp. Once seccomp is
816 enabled via /proc/<pid>/seccomp, it cannot be disabled
817 and the task is only allowed to execute a few safe syscalls
818 defined by each seccomp mode.
819
820 If unsure, say Y.
821
843c48fd
JG
822menu "Power Management"
823
824config ARCH_HIBERNATION_POSSIBLE
5a79859a 825 def_bool y
843c48fd
JG
826
827source "kernel/power/Kconfig"
828
829endmenu
830
843c48fd
JG
831config CCW
832 def_bool y
833
b6ef86e9
UB
834config HAVE_PNETID
835 tristate
836 default (SMC || CCWGROUP)
837
843c48fd 838menu "Virtualization"
684de39b 839
1da177e4 840config PFAULT
6f9a3c33
MS
841 def_bool y
842 prompt "Pseudo page fault support"
1da177e4
LT
843 help
844 Select this option, if you want to use PFAULT pseudo page fault
845 handling under VM. If running native or in LPAR, this option
846 has no effect. If your VM does not support PFAULT, PAGEEX
847 pseudo page fault handling will be used.
848 Note that VM 4.2 supports PFAULT but has a bug in its
849 implementation that causes some problems.
850 Everybody who wants to run Linux under VM != VM4.2 should select
851 this option.
852
1da177e4 853config CMM
6f9a3c33
MS
854 def_tristate n
855 prompt "Cooperative memory management"
1da177e4
LT
856 help
857 Select this option, if you want to enable the kernel interface
858 to reduce the memory size of the system. This is accomplished
859 by allocating pages of memory and put them "on hold". This only
860 makes sense for a system running under VM where the unused pages
861 will be reused by VM for other guest systems. The interface
862 allows an external monitor to balance memory of many systems.
863 Everybody who wants to run Linux under VM should select this
864 option.
865
1da177e4 866config CMM_IUCV
6f9a3c33
MS
867 def_bool y
868 prompt "IUCV special message interface to cooperative memory management"
1da177e4
LT
869 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
870 help
871 Select this option to enable the special message interface to
872 the cooperative memory management.
873
1da177e4 874config APPLDATA_BASE
6f9a3c33
MS
875 def_bool n
876 prompt "Linux - VM Monitor Stream, base infrastructure"
c185b783 877 depends on PROC_FS
1da177e4
LT
878 help
879 This provides a kernel interface for creating and updating z/VM APPLDATA
880 monitor records. The monitor records are updated at certain time
881 intervals, once the timer is started.
882 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
883 i.e. enables or disables monitoring on the Linux side.
884 A custom interval value (in seconds) can be written to
885 /proc/appldata/interval.
886
887 Defaults are 60 seconds interval and timer off.
888 The /proc entries can also be read from, showing the current settings.
889
890config APPLDATA_MEM
6f9a3c33
MS
891 def_tristate m
892 prompt "Monitor memory management statistics"
62fb2ba3 893 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
1da177e4
LT
894 help
895 This provides memory management related data to the Linux - VM Monitor
896 Stream, like paging/swapping rate, memory utilisation, etc.
897 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
898 APPLDATA monitor record, i.e. enables or disables monitoring this record
899 on the z/VM side.
900
901 Default is disabled.
902 The /proc entry can also be read from, showing the current settings.
903
904 This can also be compiled as a module, which will be called
905 appldata_mem.o.
906
907config APPLDATA_OS
6f9a3c33
MS
908 def_tristate m
909 prompt "Monitor OS statistics"
1da177e4
LT
910 depends on APPLDATA_BASE
911 help
912 This provides OS related data to the Linux - VM Monitor Stream, like
913 CPU utilisation, etc.
914 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
915 APPLDATA monitor record, i.e. enables or disables monitoring this record
916 on the z/VM side.
917
918 Default is disabled.
919 This can also be compiled as a module, which will be called
920 appldata_os.o.
921
922config APPLDATA_NET_SUM
6f9a3c33
MS
923 def_tristate m
924 prompt "Monitor overall network statistics"
70193af9 925 depends on APPLDATA_BASE && NET
1da177e4
LT
926 help
927 This provides network related data to the Linux - VM Monitor Stream,
928 currently there is only a total sum of network I/O statistics, no
929 per-interface data.
930 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
931 APPLDATA monitor record, i.e. enables or disables monitoring this record
932 on the z/VM side.
933
934 Default is disabled.
935 This can also be compiled as a module, which will be called
936 appldata_net_sum.o.
937
24bbb1fa 938config S390_HYPFS_FS
6f9a3c33
MS
939 def_bool y
940 prompt "s390 hypervisor file system support"
24bbb1fa 941 select SYS_HYPERVISOR
24bbb1fa
MH
942 help
943 This is a virtual file system intended to provide accounting
944 information in an s390 hypervisor environment.
945
843c48fd 946source "arch/s390/kvm/Kconfig"
411ed322 947
fa587743 948config S390_GUEST
6f9a3c33 949 def_bool y
510cf5a6 950 prompt "s390 support for virtio devices"
79b6f7fb 951 select TTY
80629b0b 952 select VIRTUALIZATION
fa587743 953 select VIRTIO
faeba830 954 select VIRTIO_CONSOLE
fa587743 955 help
bdd1fc27
CH
956 Enabling this option adds support for virtio based paravirtual device
957 drivers on s390.
1da177e4 958
20766c08 959 Select this option if you want to run the kernel as a guest under
bdd1fc27 960 the KVM hypervisor.
155af2f9
HJP
961
962endmenu