mm: remove CONFIG_NO_BOOTMEM
[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
47523c98 76 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
77 select ARCH_HAS_STRICT_KERNEL_RWX
78 select ARCH_HAS_STRICT_MODULE_RWX
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
002e6745 143 select DMA_DIRECT_OPS
5a79859a
HC
144 select HAVE_DYNAMIC_FTRACE
145 select HAVE_DYNAMIC_FTRACE_WITH_REGS
9078a549 146 select HAVE_EFFICIENT_UNALIGNED_ACCESS
d983c89c 147 select HAVE_FENTRY
0e0d04a8 148 select HAVE_FTRACE_MCOUNT_RECORD
5a79859a
HC
149 select HAVE_FUNCTION_GRAPH_TRACER
150 select HAVE_FUNCTION_TRACER
03b8c7b6 151 select HAVE_FUTEX_CMPXCHG if FUTEX
bc00b3ec 152 select HAVE_GCC_PLUGINS
0e0d04a8
HC
153 select HAVE_KERNEL_BZIP2
154 select HAVE_KERNEL_GZIP
8e2872ce 155 select HAVE_KERNEL_LZ4
0e0d04a8
HC
156 select HAVE_KERNEL_LZMA
157 select HAVE_KERNEL_LZO
89b5202e 158 select HAVE_KERNEL_UNCOMPRESSED
0e0d04a8
HC
159 select HAVE_KERNEL_XZ
160 select HAVE_KPROBES
161 select HAVE_KRETPROBES
5a79859a 162 select HAVE_KVM
21042d43 163 select HAVE_LIVEPATCH
c33eff60
HC
164 select HAVE_PERF_REGS
165 select HAVE_PERF_USER_STACK_DUMP
0e0d04a8
HC
166 select HAVE_MEMBLOCK
167 select HAVE_MEMBLOCK_NODE_MAP
50be6345 168 select HAVE_MEMBLOCK_PHYS_MAP
786d35d4 169 select HAVE_MOD_ARCH_SPECIFIC
d983c89c 170 select HAVE_NOP_MCOUNT
0e0d04a8
HC
171 select HAVE_OPROFILE
172 select HAVE_PERF_EVENTS
173 select HAVE_REGS_AND_STACK_ACCESS_API
9d6d99e3 174 select HAVE_RSEQ
0e0d04a8 175 select HAVE_SYSCALL_TRACEPOINTS
0e0d04a8 176 select HAVE_VIRT_CPU_ACCOUNTING
786d35d4 177 select MODULES_USE_ELF_RELA
7eddd99c 178 select OLD_SIGACTION
93bead43 179 select OLD_SIGSUSPEND3
bb98f396 180 select SPARSE_IRQ
0e0d04a8 181 select SYSCTL_EXCEPTION_TRACE
d5c352cd 182 select THREAD_INFO_IN_TASK
0563416b 183 select TTY
0e0d04a8 184 select VIRT_CPU_ACCOUNTING
40565b5a 185 select ARCH_HAS_SCALED_CPUTIME
93bead43 186 select VIRT_TO_BUS
42a0bb3f 187 select HAVE_NMI
3a368f74 188
1da177e4 189
fca3e357 190config SCHED_OMIT_FRAME_POINTER
6f9a3c33 191 def_bool y
fca3e357 192
c81956c9
KS
193config PGTABLE_LEVELS
194 int
1aea9b3f 195 default 5
c81956c9 196
21042d43
JS
197source "kernel/livepatch/Kconfig"
198
843c48fd
JG
199menu "Processor type and features"
200
201config HAVE_MARCH_Z900_FEATURES
202 def_bool n
203
204config HAVE_MARCH_Z990_FEATURES
205 def_bool n
206 select HAVE_MARCH_Z900_FEATURES
207
208config HAVE_MARCH_Z9_109_FEATURES
209 def_bool n
210 select HAVE_MARCH_Z990_FEATURES
211
212config HAVE_MARCH_Z10_FEATURES
213 def_bool n
214 select HAVE_MARCH_Z9_109_FEATURES
215
216config HAVE_MARCH_Z196_FEATURES
217 def_bool n
218 select HAVE_MARCH_Z10_FEATURES
219
991c1505
HC
220config HAVE_MARCH_ZEC12_FEATURES
221 def_bool n
222 select HAVE_MARCH_Z196_FEATURES
223
f8b2dcbd
MS
224config HAVE_MARCH_Z13_FEATURES
225 def_bool n
226 select HAVE_MARCH_ZEC12_FEATURES
227
6997c323
MS
228config HAVE_MARCH_Z14_FEATURES
229 def_bool n
230 select HAVE_MARCH_Z13_FEATURES
231
843c48fd
JG
232choice
233 prompt "Processor type"
7072276e 234 default MARCH_Z196
1da177e4 235
843c48fd
JG
236config MARCH_Z900
237 bool "IBM zSeries model z800 and z900"
5a79859a 238 select HAVE_MARCH_Z900_FEATURES
843c48fd
JG
239 help
240 Select this to enable optimizations for model z800/z900 (2064 and
241 2066 series). This will enable some optimizations that are not
242 available on older ESA/390 (31 Bit) only CPUs.
243
244config MARCH_Z990
245 bool "IBM zSeries model z890 and z990"
5a79859a 246 select HAVE_MARCH_Z990_FEATURES
843c48fd
JG
247 help
248 Select this to enable optimizations for model z890/z990 (2084 and
249 2086 series). The kernel will be slightly faster but will not work
250 on older machines.
251
252config MARCH_Z9_109
253 bool "IBM System z9"
5a79859a 254 select HAVE_MARCH_Z9_109_FEATURES
843c48fd
JG
255 help
256 Select this to enable optimizations for IBM System z9 (2094 and
257 2096 series). The kernel will be slightly faster but will not work
258 on older machines.
259
260config MARCH_Z10
261 bool "IBM System z10"
5a79859a 262 select HAVE_MARCH_Z10_FEATURES
843c48fd
JG
263 help
264 Select this to enable optimizations for IBM System z10 (2097 and
265 2098 series). The kernel will be slightly faster but will not work
266 on older machines.
267
268config MARCH_Z196
269 bool "IBM zEnterprise 114 and 196"
5a79859a 270 select HAVE_MARCH_Z196_FEATURES
843c48fd
JG
271 help
272 Select this to enable optimizations for IBM zEnterprise 114 and 196
273 (2818 and 2817 series). The kernel will be slightly faster but will
274 not work on older machines.
1da177e4 275
991c1505 276config MARCH_ZEC12
59471227 277 bool "IBM zBC12 and zEC12"
5a79859a 278 select HAVE_MARCH_ZEC12_FEATURES
991c1505 279 help
59471227
HC
280 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
281 2827 series). The kernel will be slightly faster but will not work on
282 older machines.
991c1505 283
f8b2dcbd 284config MARCH_Z13
bb3aa614 285 bool "IBM z13s and z13"
5a79859a 286 select HAVE_MARCH_Z13_FEATURES
f8b2dcbd 287 help
bb3aa614
HC
288 Select this to enable optimizations for IBM z13s and z13 (2965 and
289 2964 series). The kernel will be slightly faster but will not work on
290 older machines.
f8b2dcbd 291
6997c323 292config MARCH_Z14
451239eb 293 bool "IBM z14 ZR1 and z14"
6997c323
MS
294 select HAVE_MARCH_Z14_FEATURES
295 help
451239eb
HC
296 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
297 and 3906 series). The kernel will be slightly faster but will not
298 work on older machines.
6997c323 299
843c48fd 300endchoice
1da177e4 301
1db9e051
HC
302config MARCH_Z900_TUNE
303 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
304
305config MARCH_Z990_TUNE
306 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
307
308config MARCH_Z9_109_TUNE
309 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
310
311config MARCH_Z10_TUNE
312 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
313
314config MARCH_Z196_TUNE
315 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
316
317config MARCH_ZEC12_TUNE
318 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
319
f8b2dcbd
MS
320config MARCH_Z13_TUNE
321 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
322
6997c323
MS
323config MARCH_Z14_TUNE
324 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
325
1db9e051
HC
326choice
327 prompt "Tune code generation"
328 default TUNE_DEFAULT
329 help
330 Cause the compiler to tune (-mtune) the generated code for a machine.
331 This will make the code run faster on the selected machine but
332 somewhat slower on other machines.
333 This option only changes how the compiler emits instructions, not the
334 selection of instructions itself, so the resulting kernel will run on
335 all other machines.
336
337config TUNE_DEFAULT
338 bool "Default"
339 help
340 Tune the generated code for the target processor for which the kernel
341 will be compiled.
342
1db9e051
HC
343config TUNE_Z900
344 bool "IBM zSeries model z800 and z900"
345
346config TUNE_Z990
347 bool "IBM zSeries model z890 and z990"
348
349config TUNE_Z9_109
350 bool "IBM System z9"
351
352config TUNE_Z10
353 bool "IBM System z10"
354
355config TUNE_Z196
356 bool "IBM zEnterprise 114 and 196"
357
358config TUNE_ZEC12
359 bool "IBM zBC12 and zEC12"
360
f8b2dcbd
MS
361config TUNE_Z13
362 bool "IBM z13"
363
6997c323
MS
364config TUNE_Z14
365 bool "IBM z14"
366
1db9e051
HC
367endchoice
368
347a8dc3 369config 64BIT
6f9a3c33 370 def_bool y
d9f7a745 371
843c48fd
JG
372config COMPAT
373 def_bool y
374 prompt "Kernel support for 31 bit emulation"
843c48fd
JG
375 select COMPAT_BINFMT_ELF if BINFMT_ELF
376 select ARCH_WANT_OLD_COMPAT_IPC
7eddd99c 377 select COMPAT_OLD_SIGACTION
2813893f 378 depends on MULTIUSER
843c48fd
JG
379 help
380 Select this option if you want to enable your system kernel to
381 handle system-calls from ELF binaries for 31 bit ESA. This option
382 (and some other stuff like libraries and such) is needed for
383 executing 31 bit applications. It is safe to say "Y".
384
385config SYSVIPC_COMPAT
386 def_bool y if COMPAT && SYSVIPC
387
1da177e4 388config SMP
6f9a3c33
MS
389 def_bool y
390 prompt "Symmetric multi-processing support"
1da177e4
LT
391 ---help---
392 This enables support for systems with more than one CPU. If you have
393 a system with only one CPU, like most personal computers, say N. If
394 you have a system with more than one CPU, say Y.
395
4a474157 396 If you say N here, the kernel will run on uni- and multiprocessor
1da177e4
LT
397 machines, but will use only one CPU of a multiprocessor machine. If
398 you say Y here, the kernel will run on many, but not all,
4a474157 399 uniprocessor machines. On a uniprocessor machine, the kernel
1da177e4
LT
400 will run faster if you say N here.
401
03502faa
AB
402 See also the SMP-HOWTO available at
403 <http://www.tldp.org/docs.html#howto>.
1da177e4
LT
404
405 Even if you don't know what to do here, say Y.
406
407config NR_CPUS
5c75a0da
HC
408 int "Maximum number of CPUs (2-512)"
409 range 2 512
1da177e4 410 depends on SMP
5a79859a 411 default "64"
1da177e4
LT
412 help
413 This allows you to specify the maximum number of CPUs which this
5c75a0da 414 kernel will support. The maximum supported value is 512 and the
1da177e4
LT
415 minimum value which makes sense is 2.
416
417 This is purely to save memory - each supported CPU adds
418 approximately sixteen kilobytes to the kernel image.
419
420config HOTPLUG_CPU
6f9a3c33
MS
421 def_bool y
422 prompt "Support for hot-pluggable CPUs"
1da177e4 423 depends on SMP
1da177e4
LT
424 help
425 Say Y here to be able to turn CPUs off and on. CPUs
426 can be controlled through /sys/devices/system/cpu/cpu#.
427 Say N if you want to disable CPU hotplug.
428
3a368f74
PH
429# Some NUMA nodes have memory ranges that span
430# other nodes. Even though a pfn is valid and
431# between a node's start and end pfns, it may not
432# reside on that node. See memmap_init_zone()
433# for details. <- They meant memory holes!
434config NODES_SPAN_OTHER_NODES
435 def_bool NUMA
436
437config NUMA
438 bool "NUMA support"
c095a949 439 depends on SMP && SCHED_TOPOLOGY
3a368f74
PH
440 default n
441 help
442 Enable NUMA support
443
444 This option adds NUMA support to the kernel.
445
446 An operation mode can be selected by appending
447 numa=<method> to the kernel command line.
448
449 The default behaviour is identical to appending numa=plain to
450 the command line. This will create just one node with all
451 available memory and all CPUs in it.
452
453config NODES_SHIFT
454 int "Maximum NUMA nodes (as a power of 2)"
455 range 1 10
456 depends on NUMA
457 default "4"
458 help
459 Specify the maximum number of NUMA nodes available on the target
460 system. Increases memory reserved to accommodate various tables.
461
c29a7baf
MH
462menu "Select NUMA modes"
463 depends on NUMA
464
465config NUMA_EMU
466 bool "NUMA emulation"
467 default y
468 help
469 Numa emulation mode will split the available system memory into
470 equal chunks which then are distributed over the configured number
471 of nodes in a round-robin manner.
472
473 The number of fake nodes is limited by the number of available memory
474 chunks (i.e. memory size / fake size) and the number of supported
475 nodes in the kernel.
476
477 The CPUs are assigned to the nodes in a way that partially respects
478 the original machine topology (if supported by the machine).
479 Fair distribution of the CPUs is not guaranteed.
480
481config EMU_SIZE
482 hex "NUMA emulation memory chunk size"
483 default 0x10000000
484 range 0x400000 0x100000000
485 depends on NUMA_EMU
486 help
487 Select the default size by which the memory is chopped and then
488 assigned to emulated NUMA nodes.
489
490 This can be overridden by specifying
491
492 emu_size=<n>
493
494 on the kernel command line where also suffixes K, M, G, and T are
495 supported.
496
497endmenu
9236b4dd
HC
498
499config SCHED_SMT
500 def_bool n
c29a7baf 501
8d11e021 502config SCHED_MC
83a24e32 503 def_bool n
8d11e021 504
4cb14bc8 505config SCHED_BOOK
10ad34bc
MS
506 def_bool n
507
adac0f1e
HC
508config SCHED_DRAWER
509 def_bool n
510
10ad34bc 511config SCHED_TOPOLOGY
6f9a3c33 512 def_bool y
10ad34bc 513 prompt "Topology scheduler support"
83a24e32 514 depends on SMP
10ad34bc 515 select SCHED_SMT
83a24e32 516 select SCHED_MC
10ad34bc 517 select SCHED_BOOK
adac0f1e 518 select SCHED_DRAWER
4cb14bc8 519 help
10ad34bc
MS
520 Topology scheduler support improves the CPU scheduler's decision
521 making when dealing with machines that have multi-threading,
522 multiple cores or multiple books.
4cb14bc8 523
843c48fd 524source kernel/Kconfig.hz
1da177e4 525
bdea9f6f
PR
526config KEXEC
527 def_bool y
528 select KEXEC_CORE
529
530config KEXEC_FILE
531 bool "kexec file based system call"
532 select KEXEC_CORE
533 select BUILD_BIN2C
534 depends on CRYPTO
535 depends on CRYPTO_SHA256
536 depends on CRYPTO_SHA256_S390
537 help
538 Enable the kexec file based system call. In contrast to the normal
539 kexec system call this system call takes file descriptors for the
540 kernel and initramfs as arguments.
541
542config ARCH_HAS_KEXEC_PURGATORY
543 def_bool y
544 depends on KEXEC_FILE
545
4c637cd8
HF
546config ARCH_RANDOM
547 def_bool y
548 prompt "s390 architectural random number generation API"
549 help
550 Enable the s390 architectural random number generation API
551 to provide random data for all consumers within the Linux
552 kernel.
553
554 When enabled the arch_random_* functions declared in linux/random.h
555 are implemented. The implementation is based on the s390 CPACF
556 instruction subfunction TRNG which provides a real true random
557 number generator.
558
559 If unsure, say Y.
560
d768bd89
MS
561config KERNEL_NOBP
562 def_bool n
563 prompt "Enable modified branch prediction for the kernel by default"
564 help
565 If this option is selected the kernel will switch to a modified
566 branch prediction mode if the firmware interface is available.
567 The modified branch prediction mode improves the behaviour in
568 regard to speculative execution.
569
570 With the option enabled the kernel parameter "nobp=0" or "nospec"
571 can be used to run the kernel in the normal branch prediction mode.
572
573 With the option disabled the modified branch prediction mode is
574 enabled with the "nobp=1" kernel parameter.
575
576 If unsure, say N.
577
f19fbd5e
MS
578config EXPOLINE
579 def_bool n
580 prompt "Avoid speculative indirect branches in the kernel"
581 help
582 Compile the kernel with the expoline compiler options to guard
583 against kernel-to-user data leaks by avoiding speculative indirect
584 branches.
585 Requires a compiler with -mindirect-branch=thunk support for full
586 protection. The kernel may run slower.
587
588 If unsure, say N.
589
590choice
591 prompt "Expoline default"
592 depends on EXPOLINE
593 default EXPOLINE_FULL
594
595config EXPOLINE_OFF
596 bool "spectre_v2=off"
597
6e179d64 598config EXPOLINE_AUTO
f19fbd5e
MS
599 bool "spectre_v2=auto"
600
601config EXPOLINE_FULL
602 bool "spectre_v2=on"
603
604endchoice
605
843c48fd 606endmenu
1da177e4 607
843c48fd 608menu "Memory setup"
1d057720 609
843c48fd 610config ARCH_SPARSEMEM_ENABLE
6f9a3c33 611 def_bool y
843c48fd
JG
612 select SPARSEMEM_VMEMMAP_ENABLE
613 select SPARSEMEM_VMEMMAP
e65e1fc2 614
843c48fd
JG
615config ARCH_SPARSEMEM_DEFAULT
616 def_bool y
1da177e4 617
843c48fd
JG
618config ARCH_SELECT_MEMORY_MODEL
619 def_bool y
1da177e4 620
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JG
621config ARCH_ENABLE_MEMORY_HOTPLUG
622 def_bool y if SPARSEMEM
0efa4703 623
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JG
624config ARCH_ENABLE_MEMORY_HOTREMOVE
625 def_bool y
e37f50e1 626
ec66ad66
MS
627config ARCH_ENABLE_SPLIT_PMD_PTLOCK
628 def_bool y
ec66ad66 629
843c48fd
JG
630config FORCE_MAX_ZONEORDER
631 int
632 default "9"
f861e405 633
b8402b95
HC
634config MAX_PHYSMEM_BITS
635 int "Maximum size of supported physical memory in bits (42-53)"
636 range 42 53
637 default "46"
638 help
639 This option specifies the maximum supported size of physical memory
640 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
641 Increasing the number of bits also increases the kernel image size.
642 By default 46 bits (64TB) are supported.
643
1da177e4 644config PACK_STACK
6f9a3c33
MS
645 def_bool y
646 prompt "Pack kernel stack"
1da177e4
LT
647 help
648 This option enables the compiler option -mkernel-backchain if it
649 is available. If the option is available the compiler supports
650 the new stack layout which dramatically reduces the minimum stack
651 frame size. With an old compiler a non-leaf function needs a
652 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
653 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
654 and 24 byte on 64 bit.
655
656 Say Y if you are unsure.
657
1da177e4 658config CHECK_STACK
6f9a3c33 659 def_bool y
ce3dc447 660 depends on !VMAP_STACK
6f9a3c33 661 prompt "Detect kernel stack overflow"
1da177e4
LT
662 help
663 This option enables the compiler option -mstack-guard and
664 -mstack-size if they are available. If the compiler supports them
665 it will emit additional code to each function prolog to trigger
666 an illegal operation if the kernel stack is about to overflow.
667
668 Say N if you are unsure.
669
670config STACK_GUARD
671 int "Size of the guard area (128-1024)"
672 range 128 1024
673 depends on CHECK_STACK
674 default "256"
675 help
676 This allows you to specify the size of the guard area at the lower
677 end of the kernel stack. If the kernel stack points into the guard
678 area on function entry an illegal operation is triggered. The size
679 needs to be a power of 2. Please keep in mind that the size of an
680 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
681 The minimum size for the stack guard should be 256 for 31 bit and
682 512 for 64 bit.
683
2c190da4 684config WARN_DYNAMIC_STACK
6f9a3c33 685 def_bool n
2c190da4 686 prompt "Emit compiler warnings for function with dynamic stack usage"
1da177e4 687 help
2c190da4
JG
688 This option enables the compiler option -mwarn-dynamicstack. If the
689 compiler supports this options generates warnings for functions
690 that dynamically allocate stack space using alloca.
1da177e4
LT
691
692 Say N if you are unsure.
693
843c48fd 694endmenu
3f22ab27 695
843c48fd 696menu "I/O subsystem"
1da177e4 697
1da177e4 698config QDIO
6f9a3c33
MS
699 def_tristate y
700 prompt "QDIO support"
1da177e4 701 ---help---
8129ee16 702 This driver provides the Queued Direct I/O base support for
efca13bc 703 IBM System z.
1da177e4
LT
704
705 To compile this driver as a module, choose M here: the
706 module will be called qdio.
707
708 If unsure, say Y.
709
c8717a3d
JG
710menuconfig PCI
711 bool "PCI support"
c8717a3d 712 select PCI_MSI
a4ce5a48 713 select IOMMU_HELPER
8128f23c 714 select IOMMU_SUPPORT
f616ab59 715 select NEED_DMA_MAP_STATE
86596f0a 716 select NEED_SG_DMA_LENGTH
a4ce5a48 717
c8717a3d
JG
718 help
719 Enable PCI support.
720
721if PCI
722
723config PCI_NR_FUNCTIONS
724 int "Maximum number of PCI functions (1-4096)"
725 range 1 4096
b18601b0 726 default "128"
c8717a3d
JG
727 help
728 This allows you to specify the maximum number of PCI functions which
729 this kernel will support.
730
731source "drivers/pci/Kconfig"
c8717a3d
JG
732
733endif # PCI
734
735config PCI_DOMAINS
736 def_bool PCI
737
738config HAS_IOMEM
739 def_bool PCI
740
9d92a7e1 741config CHSC_SCH
d9c11b1e 742 def_tristate m
6f9a3c33 743 prompt "Support for CHSC subchannels"
9d92a7e1
CH
744 help
745 This driver allows usage of CHSC subchannels. A CHSC subchannel
746 is usually present on LPAR only.
747 The driver creates a device /dev/chsc, which may be used to
748 obtain I/O configuration information about the machine and
749 to issue asynchronous chsc commands (DANGEROUS).
750 You will usually only want to use this interface on a special
751 LPAR designated for system management.
752
753 To compile this driver as a module, choose M here: the
754 module will be called chsc_sch.
755
756 If unsure, say N.
757
1d1c8f78
SO
758config SCM_BUS
759 def_bool y
1d1c8f78
SO
760 prompt "SCM bus driver"
761 help
762 Bus driver for Storage Class Memory.
763
eadb86ab
SO
764config EADM_SCH
765 def_tristate m
766 prompt "Support for EADM subchannels"
767 depends on SCM_BUS
768 help
769 This driver allows usage of EADM subchannels. EADM subchannels act
770 as a communication vehicle for SCM increments.
771
772 To compile this driver as a module, choose M here: the
773 module will be called eadm_sch.
774
63f1934d
DJS
775config VFIO_CCW
776 def_tristate n
777 prompt "Support for VFIO-CCW subchannels"
84cd8fc4 778 depends on S390_CCW_IOMMU && VFIO_MDEV
63f1934d
DJS
779 help
780 This driver allows usage of I/O subchannels via VFIO-CCW.
781
782 To compile this driver as a module, choose M here: the
783 module will be called vfio_ccw.
784
1fde5734
TK
785config VFIO_AP
786 def_tristate n
787 prompt "VFIO support for AP devices"
788 depends on S390_AP_IOMMU && VFIO_MDEV_DEVICE && KVM
789 help
790 This driver grants access to Adjunct Processor (AP) devices
791 via the VFIO mediated device interface.
792
793 To compile this driver as a module, choose M here: the module
794 will be called vfio_ap.
795
843c48fd
JG
796endmenu
797
798menu "Dump support"
799
800config CRASH_DUMP
801 bool "kernel crash dumps"
5a79859a 802 depends on SMP
843c48fd
JG
803 select KEXEC
804 help
805 Generate crash dump after being started by kexec.
806 Crash dump kernels are loaded in the main kernel with kexec-tools
807 into a specially reserved region and then later executed after
808 a crash by kdump/kexec.
843c48fd 809 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
bf28a597
MH
810 This option also enables s390 zfcpdump.
811 See also <file:Documentation/s390/zfcpdump.txt>
843c48fd
JG
812
813endmenu
814
843c48fd
JG
815config SECCOMP
816 def_bool y
817 prompt "Enable seccomp to safely compute untrusted bytecode"
818 depends on PROC_FS
819 help
820 This kernel feature is useful for number crunching applications
821 that may need to compute untrusted bytecode during their
822 execution. By using pipes or other transports made available to
823 the process as file descriptors supporting the read/write
824 syscalls, it's possible to isolate those applications in
825 their own address space using seccomp. Once seccomp is
826 enabled via /proc/<pid>/seccomp, it cannot be disabled
827 and the task is only allowed to execute a few safe syscalls
828 defined by each seccomp mode.
829
830 If unsure, say Y.
831
843c48fd
JG
832menu "Power Management"
833
834config ARCH_HIBERNATION_POSSIBLE
5a79859a 835 def_bool y
843c48fd
JG
836
837source "kernel/power/Kconfig"
838
839endmenu
840
843c48fd
JG
841config PCMCIA
842 def_bool n
843
844config CCW
845 def_bool y
846
b6ef86e9
UB
847config HAVE_PNETID
848 tristate
849 default (SMC || CCWGROUP)
850
843c48fd 851menu "Virtualization"
684de39b 852
1da177e4 853config PFAULT
6f9a3c33
MS
854 def_bool y
855 prompt "Pseudo page fault support"
1da177e4
LT
856 help
857 Select this option, if you want to use PFAULT pseudo page fault
858 handling under VM. If running native or in LPAR, this option
859 has no effect. If your VM does not support PFAULT, PAGEEX
860 pseudo page fault handling will be used.
861 Note that VM 4.2 supports PFAULT but has a bug in its
862 implementation that causes some problems.
863 Everybody who wants to run Linux under VM != VM4.2 should select
864 this option.
865
1da177e4 866config CMM
6f9a3c33
MS
867 def_tristate n
868 prompt "Cooperative memory management"
1da177e4
LT
869 help
870 Select this option, if you want to enable the kernel interface
871 to reduce the memory size of the system. This is accomplished
872 by allocating pages of memory and put them "on hold". This only
873 makes sense for a system running under VM where the unused pages
874 will be reused by VM for other guest systems. The interface
875 allows an external monitor to balance memory of many systems.
876 Everybody who wants to run Linux under VM should select this
877 option.
878
1da177e4 879config CMM_IUCV
6f9a3c33
MS
880 def_bool y
881 prompt "IUCV special message interface to cooperative memory management"
1da177e4
LT
882 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
883 help
884 Select this option to enable the special message interface to
885 the cooperative memory management.
886
1da177e4 887config APPLDATA_BASE
6f9a3c33
MS
888 def_bool n
889 prompt "Linux - VM Monitor Stream, base infrastructure"
c185b783 890 depends on PROC_FS
1da177e4
LT
891 help
892 This provides a kernel interface for creating and updating z/VM APPLDATA
893 monitor records. The monitor records are updated at certain time
894 intervals, once the timer is started.
895 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
896 i.e. enables or disables monitoring on the Linux side.
897 A custom interval value (in seconds) can be written to
898 /proc/appldata/interval.
899
900 Defaults are 60 seconds interval and timer off.
901 The /proc entries can also be read from, showing the current settings.
902
903config APPLDATA_MEM
6f9a3c33
MS
904 def_tristate m
905 prompt "Monitor memory management statistics"
62fb2ba3 906 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
1da177e4
LT
907 help
908 This provides memory management related data to the Linux - VM Monitor
909 Stream, like paging/swapping rate, memory utilisation, etc.
910 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
911 APPLDATA monitor record, i.e. enables or disables monitoring this record
912 on the z/VM side.
913
914 Default is disabled.
915 The /proc entry can also be read from, showing the current settings.
916
917 This can also be compiled as a module, which will be called
918 appldata_mem.o.
919
920config APPLDATA_OS
6f9a3c33
MS
921 def_tristate m
922 prompt "Monitor OS statistics"
1da177e4
LT
923 depends on APPLDATA_BASE
924 help
925 This provides OS related data to the Linux - VM Monitor Stream, like
926 CPU utilisation, etc.
927 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
928 APPLDATA monitor record, i.e. enables or disables monitoring this record
929 on the z/VM side.
930
931 Default is disabled.
932 This can also be compiled as a module, which will be called
933 appldata_os.o.
934
935config APPLDATA_NET_SUM
6f9a3c33
MS
936 def_tristate m
937 prompt "Monitor overall network statistics"
70193af9 938 depends on APPLDATA_BASE && NET
1da177e4
LT
939 help
940 This provides network related data to the Linux - VM Monitor Stream,
941 currently there is only a total sum of network I/O statistics, no
942 per-interface data.
943 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
944 APPLDATA monitor record, i.e. enables or disables monitoring this record
945 on the z/VM side.
946
947 Default is disabled.
948 This can also be compiled as a module, which will be called
949 appldata_net_sum.o.
950
24bbb1fa 951config S390_HYPFS_FS
6f9a3c33
MS
952 def_bool y
953 prompt "s390 hypervisor file system support"
24bbb1fa 954 select SYS_HYPERVISOR
24bbb1fa
MH
955 help
956 This is a virtual file system intended to provide accounting
957 information in an s390 hypervisor environment.
958
843c48fd 959source "arch/s390/kvm/Kconfig"
411ed322 960
fa587743 961config S390_GUEST
6f9a3c33 962 def_bool y
510cf5a6 963 prompt "s390 support for virtio devices"
79b6f7fb 964 select TTY
80629b0b 965 select VIRTUALIZATION
fa587743 966 select VIRTIO
faeba830 967 select VIRTIO_CONSOLE
fa587743 968 help
bdd1fc27
CH
969 Enabling this option adds support for virtio based paravirtual device
970 drivers on s390.
1da177e4 971
20766c08 972 Select this option if you want to run the kernel as a guest under
bdd1fc27 973 the KVM hypervisor.
155af2f9
HJP
974
975endmenu