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KVM: s390: refactor crypto initialization
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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
347a8dc3 59config S390
61d48c2c 60 def_bool y
23fefe11 61 select ARCH_BINFMT_ELF_STATE
21266be9 62 select ARCH_HAS_DEVMEM_IS_ALLOWED
2b68f6ca 63 select ARCH_HAS_ELF_RANDOMIZE
79962038 64 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 65 select ARCH_HAS_GCOV_PROFILE_ALL
e1073d1e 66 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
907fa061 67 select ARCH_HAS_KCOV
3010a5ea 68 select ARCH_HAS_PTE_SPECIAL
d2852a22 69 select ARCH_HAS_SET_MEMORY
47523c98 70 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
71 select ARCH_HAS_STRICT_KERNEL_RWX
72 select ARCH_HAS_STRICT_MODULE_RWX
c42d8c7d 73 select ARCH_HAS_UBSAN_SANITIZE_ALL
0e0d04a8 74 select ARCH_HAVE_NMI_SAFE_CMPXCHG
6beb0009
TG
75 select ARCH_INLINE_READ_LOCK
76 select ARCH_INLINE_READ_LOCK_BH
77 select ARCH_INLINE_READ_LOCK_IRQ
78 select ARCH_INLINE_READ_LOCK_IRQSAVE
0e0d04a8 79 select ARCH_INLINE_READ_TRYLOCK
6beb0009
TG
80 select ARCH_INLINE_READ_UNLOCK
81 select ARCH_INLINE_READ_UNLOCK_BH
82 select ARCH_INLINE_READ_UNLOCK_IRQ
83 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
0e0d04a8
HC
84 select ARCH_INLINE_SPIN_LOCK
85 select ARCH_INLINE_SPIN_LOCK_BH
86 select ARCH_INLINE_SPIN_LOCK_IRQ
87 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
88 select ARCH_INLINE_SPIN_TRYLOCK
89 select ARCH_INLINE_SPIN_TRYLOCK_BH
90 select ARCH_INLINE_SPIN_UNLOCK
91 select ARCH_INLINE_SPIN_UNLOCK_BH
92 select ARCH_INLINE_SPIN_UNLOCK_IRQ
93 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
6beb0009
TG
94 select ARCH_INLINE_WRITE_LOCK
95 select ARCH_INLINE_WRITE_LOCK_BH
96 select ARCH_INLINE_WRITE_LOCK_IRQ
97 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
0e0d04a8 98 select ARCH_INLINE_WRITE_TRYLOCK
6beb0009
TG
99 select ARCH_INLINE_WRITE_UNLOCK
100 select ARCH_INLINE_WRITE_UNLOCK_BH
101 select ARCH_INLINE_WRITE_UNLOCK_IRQ
102 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
0e0d04a8 103 select ARCH_SAVE_PAGE_KEYS if HIBERNATION
36e7fdaa 104 select ARCH_SUPPORTS_ATOMIC_RMW
a763bc8b 105 select ARCH_SUPPORTS_NUMA_BALANCING
295d8fa9 106 select ARCH_USE_BUILTIN_BSWAP
efc1d23b 107 select ARCH_USE_CMPXCHG_LOCKREF
3f6813b9 108 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
c1d7e01d 109 select ARCH_WANT_IPC_PARSE_VERSION
0e0d04a8
HC
110 select BUILDTIME_EXTABLE_SORT
111 select CLONE_BACKWARDS2
5d6a0163 112 select DYNAMIC_FTRACE if FUNCTION_TRACER
0e0d04a8 113 select GENERIC_CLOCKEVENTS
8f00b3e2 114 select GENERIC_CPU_AUTOPROBE
0e0d04a8 115 select GENERIC_CPU_DEVICES if !SMP
d424986f 116 select GENERIC_CPU_VULNERABILITIES
746479cd 117 select GENERIC_FIND_FIRST_BIT
e80e7813 118 select GENERIC_SMP_IDLE_THREAD
79c74ecb 119 select GENERIC_TIME_VSYSCALL
0e0d04a8 120 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
7a017721 121 select HAVE_ARCH_AUDITSYSCALL
5a79859a 122 select HAVE_ARCH_JUMP_LABEL
fff7fb0b 123 select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
c63cb468 124 select HAVE_ARCH_SECCOMP_FILTER
5614dd92 125 select HAVE_ARCH_SOFT_DIRTY
0e0d04a8 126 select HAVE_ARCH_TRACEHOOK
5a79859a 127 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
6077776b 128 select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
0e0d04a8
HC
129 select HAVE_CMPXCHG_DOUBLE
130 select HAVE_CMPXCHG_LOCAL
f50c0e63 131 select HAVE_COPY_THREAD_TLS
0e0d04a8 132 select HAVE_DEBUG_KMEMLEAK
e1231b0e 133 select HAVE_DMA_CONTIGUOUS
002e6745 134 select DMA_DIRECT_OPS
5a79859a
HC
135 select HAVE_DYNAMIC_FTRACE
136 select HAVE_DYNAMIC_FTRACE_WITH_REGS
9078a549 137 select HAVE_EFFICIENT_UNALIGNED_ACCESS
d983c89c 138 select HAVE_FENTRY
0e0d04a8 139 select HAVE_FTRACE_MCOUNT_RECORD
5a79859a
HC
140 select HAVE_FUNCTION_GRAPH_TRACER
141 select HAVE_FUNCTION_TRACER
03b8c7b6 142 select HAVE_FUTEX_CMPXCHG if FUTEX
bc00b3ec 143 select HAVE_GCC_PLUGINS
0e0d04a8
HC
144 select HAVE_KERNEL_BZIP2
145 select HAVE_KERNEL_GZIP
8e2872ce 146 select HAVE_KERNEL_LZ4
0e0d04a8
HC
147 select HAVE_KERNEL_LZMA
148 select HAVE_KERNEL_LZO
89b5202e 149 select HAVE_KERNEL_UNCOMPRESSED
0e0d04a8
HC
150 select HAVE_KERNEL_XZ
151 select HAVE_KPROBES
152 select HAVE_KRETPROBES
5a79859a 153 select HAVE_KVM
21042d43 154 select HAVE_LIVEPATCH
c33eff60
HC
155 select HAVE_PERF_REGS
156 select HAVE_PERF_USER_STACK_DUMP
0e0d04a8
HC
157 select HAVE_MEMBLOCK
158 select HAVE_MEMBLOCK_NODE_MAP
50be6345 159 select HAVE_MEMBLOCK_PHYS_MAP
786d35d4 160 select HAVE_MOD_ARCH_SPECIFIC
d983c89c 161 select HAVE_NOP_MCOUNT
0e0d04a8
HC
162 select HAVE_OPROFILE
163 select HAVE_PERF_EVENTS
164 select HAVE_REGS_AND_STACK_ACCESS_API
9d6d99e3 165 select HAVE_RSEQ
0e0d04a8 166 select HAVE_SYSCALL_TRACEPOINTS
0e0d04a8 167 select HAVE_VIRT_CPU_ACCOUNTING
786d35d4 168 select MODULES_USE_ELF_RELA
50be6345 169 select NO_BOOTMEM
7eddd99c 170 select OLD_SIGACTION
93bead43 171 select OLD_SIGSUSPEND3
bb98f396 172 select SPARSE_IRQ
0e0d04a8 173 select SYSCTL_EXCEPTION_TRACE
d5c352cd 174 select THREAD_INFO_IN_TASK
0563416b 175 select TTY
0e0d04a8 176 select VIRT_CPU_ACCOUNTING
40565b5a 177 select ARCH_HAS_SCALED_CPUTIME
93bead43 178 select VIRT_TO_BUS
42a0bb3f 179 select HAVE_NMI
3a368f74 180
1da177e4 181
fca3e357 182config SCHED_OMIT_FRAME_POINTER
6f9a3c33 183 def_bool y
fca3e357 184
c81956c9
KS
185config PGTABLE_LEVELS
186 int
1aea9b3f 187 default 5
c81956c9 188
21042d43
JS
189source "kernel/livepatch/Kconfig"
190
843c48fd
JG
191menu "Processor type and features"
192
193config HAVE_MARCH_Z900_FEATURES
194 def_bool n
195
196config HAVE_MARCH_Z990_FEATURES
197 def_bool n
198 select HAVE_MARCH_Z900_FEATURES
199
200config HAVE_MARCH_Z9_109_FEATURES
201 def_bool n
202 select HAVE_MARCH_Z990_FEATURES
203
204config HAVE_MARCH_Z10_FEATURES
205 def_bool n
206 select HAVE_MARCH_Z9_109_FEATURES
207
208config HAVE_MARCH_Z196_FEATURES
209 def_bool n
210 select HAVE_MARCH_Z10_FEATURES
211
991c1505
HC
212config HAVE_MARCH_ZEC12_FEATURES
213 def_bool n
214 select HAVE_MARCH_Z196_FEATURES
215
f8b2dcbd
MS
216config HAVE_MARCH_Z13_FEATURES
217 def_bool n
218 select HAVE_MARCH_ZEC12_FEATURES
219
6997c323
MS
220config HAVE_MARCH_Z14_FEATURES
221 def_bool n
222 select HAVE_MARCH_Z13_FEATURES
223
843c48fd
JG
224choice
225 prompt "Processor type"
7072276e 226 default MARCH_Z196
1da177e4 227
843c48fd
JG
228config MARCH_Z900
229 bool "IBM zSeries model z800 and z900"
5a79859a 230 select HAVE_MARCH_Z900_FEATURES
843c48fd
JG
231 help
232 Select this to enable optimizations for model z800/z900 (2064 and
233 2066 series). This will enable some optimizations that are not
234 available on older ESA/390 (31 Bit) only CPUs.
235
236config MARCH_Z990
237 bool "IBM zSeries model z890 and z990"
5a79859a 238 select HAVE_MARCH_Z990_FEATURES
843c48fd
JG
239 help
240 Select this to enable optimizations for model z890/z990 (2084 and
241 2086 series). The kernel will be slightly faster but will not work
242 on older machines.
243
244config MARCH_Z9_109
245 bool "IBM System z9"
5a79859a 246 select HAVE_MARCH_Z9_109_FEATURES
843c48fd
JG
247 help
248 Select this to enable optimizations for IBM System z9 (2094 and
249 2096 series). The kernel will be slightly faster but will not work
250 on older machines.
251
252config MARCH_Z10
253 bool "IBM System z10"
5a79859a 254 select HAVE_MARCH_Z10_FEATURES
843c48fd
JG
255 help
256 Select this to enable optimizations for IBM System z10 (2097 and
257 2098 series). The kernel will be slightly faster but will not work
258 on older machines.
259
260config MARCH_Z196
261 bool "IBM zEnterprise 114 and 196"
5a79859a 262 select HAVE_MARCH_Z196_FEATURES
843c48fd
JG
263 help
264 Select this to enable optimizations for IBM zEnterprise 114 and 196
265 (2818 and 2817 series). The kernel will be slightly faster but will
266 not work on older machines.
1da177e4 267
991c1505 268config MARCH_ZEC12
59471227 269 bool "IBM zBC12 and zEC12"
5a79859a 270 select HAVE_MARCH_ZEC12_FEATURES
991c1505 271 help
59471227
HC
272 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
273 2827 series). The kernel will be slightly faster but will not work on
274 older machines.
991c1505 275
f8b2dcbd 276config MARCH_Z13
bb3aa614 277 bool "IBM z13s and z13"
5a79859a 278 select HAVE_MARCH_Z13_FEATURES
f8b2dcbd 279 help
bb3aa614
HC
280 Select this to enable optimizations for IBM z13s and z13 (2965 and
281 2964 series). The kernel will be slightly faster but will not work on
282 older machines.
f8b2dcbd 283
6997c323 284config MARCH_Z14
451239eb 285 bool "IBM z14 ZR1 and z14"
6997c323
MS
286 select HAVE_MARCH_Z14_FEATURES
287 help
451239eb
HC
288 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
289 and 3906 series). The kernel will be slightly faster but will not
290 work on older machines.
6997c323 291
843c48fd 292endchoice
1da177e4 293
1db9e051
HC
294config MARCH_Z900_TUNE
295 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
296
297config MARCH_Z990_TUNE
298 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
299
300config MARCH_Z9_109_TUNE
301 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
302
303config MARCH_Z10_TUNE
304 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
305
306config MARCH_Z196_TUNE
307 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
308
309config MARCH_ZEC12_TUNE
310 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
311
f8b2dcbd
MS
312config MARCH_Z13_TUNE
313 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
314
6997c323
MS
315config MARCH_Z14_TUNE
316 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
317
1db9e051
HC
318choice
319 prompt "Tune code generation"
320 default TUNE_DEFAULT
321 help
322 Cause the compiler to tune (-mtune) the generated code for a machine.
323 This will make the code run faster on the selected machine but
324 somewhat slower on other machines.
325 This option only changes how the compiler emits instructions, not the
326 selection of instructions itself, so the resulting kernel will run on
327 all other machines.
328
329config TUNE_DEFAULT
330 bool "Default"
331 help
332 Tune the generated code for the target processor for which the kernel
333 will be compiled.
334
1db9e051
HC
335config TUNE_Z900
336 bool "IBM zSeries model z800 and z900"
337
338config TUNE_Z990
339 bool "IBM zSeries model z890 and z990"
340
341config TUNE_Z9_109
342 bool "IBM System z9"
343
344config TUNE_Z10
345 bool "IBM System z10"
346
347config TUNE_Z196
348 bool "IBM zEnterprise 114 and 196"
349
350config TUNE_ZEC12
351 bool "IBM zBC12 and zEC12"
352
f8b2dcbd
MS
353config TUNE_Z13
354 bool "IBM z13"
355
6997c323
MS
356config TUNE_Z14
357 bool "IBM z14"
358
1db9e051
HC
359endchoice
360
347a8dc3 361config 64BIT
6f9a3c33 362 def_bool y
d9f7a745 363
843c48fd
JG
364config COMPAT
365 def_bool y
366 prompt "Kernel support for 31 bit emulation"
843c48fd
JG
367 select COMPAT_BINFMT_ELF if BINFMT_ELF
368 select ARCH_WANT_OLD_COMPAT_IPC
7eddd99c 369 select COMPAT_OLD_SIGACTION
2813893f 370 depends on MULTIUSER
843c48fd
JG
371 help
372 Select this option if you want to enable your system kernel to
373 handle system-calls from ELF binaries for 31 bit ESA. This option
374 (and some other stuff like libraries and such) is needed for
375 executing 31 bit applications. It is safe to say "Y".
376
377config SYSVIPC_COMPAT
378 def_bool y if COMPAT && SYSVIPC
379
1da177e4 380config SMP
6f9a3c33
MS
381 def_bool y
382 prompt "Symmetric multi-processing support"
1da177e4
LT
383 ---help---
384 This enables support for systems with more than one CPU. If you have
385 a system with only one CPU, like most personal computers, say N. If
386 you have a system with more than one CPU, say Y.
387
4a474157 388 If you say N here, the kernel will run on uni- and multiprocessor
1da177e4
LT
389 machines, but will use only one CPU of a multiprocessor machine. If
390 you say Y here, the kernel will run on many, but not all,
4a474157 391 uniprocessor machines. On a uniprocessor machine, the kernel
1da177e4
LT
392 will run faster if you say N here.
393
03502faa
AB
394 See also the SMP-HOWTO available at
395 <http://www.tldp.org/docs.html#howto>.
1da177e4
LT
396
397 Even if you don't know what to do here, say Y.
398
399config NR_CPUS
5c75a0da
HC
400 int "Maximum number of CPUs (2-512)"
401 range 2 512
1da177e4 402 depends on SMP
5a79859a 403 default "64"
1da177e4
LT
404 help
405 This allows you to specify the maximum number of CPUs which this
5c75a0da 406 kernel will support. The maximum supported value is 512 and the
1da177e4
LT
407 minimum value which makes sense is 2.
408
409 This is purely to save memory - each supported CPU adds
410 approximately sixteen kilobytes to the kernel image.
411
412config HOTPLUG_CPU
6f9a3c33
MS
413 def_bool y
414 prompt "Support for hot-pluggable CPUs"
1da177e4 415 depends on SMP
1da177e4
LT
416 help
417 Say Y here to be able to turn CPUs off and on. CPUs
418 can be controlled through /sys/devices/system/cpu/cpu#.
419 Say N if you want to disable CPU hotplug.
420
3a368f74
PH
421# Some NUMA nodes have memory ranges that span
422# other nodes. Even though a pfn is valid and
423# between a node's start and end pfns, it may not
424# reside on that node. See memmap_init_zone()
425# for details. <- They meant memory holes!
426config NODES_SPAN_OTHER_NODES
427 def_bool NUMA
428
429config NUMA
430 bool "NUMA support"
c095a949 431 depends on SMP && SCHED_TOPOLOGY
3a368f74
PH
432 default n
433 help
434 Enable NUMA support
435
436 This option adds NUMA support to the kernel.
437
438 An operation mode can be selected by appending
439 numa=<method> to the kernel command line.
440
441 The default behaviour is identical to appending numa=plain to
442 the command line. This will create just one node with all
443 available memory and all CPUs in it.
444
445config NODES_SHIFT
446 int "Maximum NUMA nodes (as a power of 2)"
447 range 1 10
448 depends on NUMA
449 default "4"
450 help
451 Specify the maximum number of NUMA nodes available on the target
452 system. Increases memory reserved to accommodate various tables.
453
c29a7baf
MH
454menu "Select NUMA modes"
455 depends on NUMA
456
457config NUMA_EMU
458 bool "NUMA emulation"
459 default y
460 help
461 Numa emulation mode will split the available system memory into
462 equal chunks which then are distributed over the configured number
463 of nodes in a round-robin manner.
464
465 The number of fake nodes is limited by the number of available memory
466 chunks (i.e. memory size / fake size) and the number of supported
467 nodes in the kernel.
468
469 The CPUs are assigned to the nodes in a way that partially respects
470 the original machine topology (if supported by the machine).
471 Fair distribution of the CPUs is not guaranteed.
472
473config EMU_SIZE
474 hex "NUMA emulation memory chunk size"
475 default 0x10000000
476 range 0x400000 0x100000000
477 depends on NUMA_EMU
478 help
479 Select the default size by which the memory is chopped and then
480 assigned to emulated NUMA nodes.
481
482 This can be overridden by specifying
483
484 emu_size=<n>
485
486 on the kernel command line where also suffixes K, M, G, and T are
487 supported.
488
489endmenu
9236b4dd
HC
490
491config SCHED_SMT
492 def_bool n
c29a7baf 493
8d11e021 494config SCHED_MC
83a24e32 495 def_bool n
8d11e021 496
4cb14bc8 497config SCHED_BOOK
10ad34bc
MS
498 def_bool n
499
adac0f1e
HC
500config SCHED_DRAWER
501 def_bool n
502
10ad34bc 503config SCHED_TOPOLOGY
6f9a3c33 504 def_bool y
10ad34bc 505 prompt "Topology scheduler support"
83a24e32 506 depends on SMP
10ad34bc 507 select SCHED_SMT
83a24e32 508 select SCHED_MC
10ad34bc 509 select SCHED_BOOK
adac0f1e 510 select SCHED_DRAWER
4cb14bc8 511 help
10ad34bc
MS
512 Topology scheduler support improves the CPU scheduler's decision
513 making when dealing with machines that have multi-threading,
514 multiple cores or multiple books.
4cb14bc8 515
843c48fd 516source kernel/Kconfig.hz
1da177e4 517
bdea9f6f
PR
518config KEXEC
519 def_bool y
520 select KEXEC_CORE
521
522config KEXEC_FILE
523 bool "kexec file based system call"
524 select KEXEC_CORE
525 select BUILD_BIN2C
526 depends on CRYPTO
527 depends on CRYPTO_SHA256
528 depends on CRYPTO_SHA256_S390
529 help
530 Enable the kexec file based system call. In contrast to the normal
531 kexec system call this system call takes file descriptors for the
532 kernel and initramfs as arguments.
533
534config ARCH_HAS_KEXEC_PURGATORY
535 def_bool y
536 depends on KEXEC_FILE
537
4c637cd8
HF
538config ARCH_RANDOM
539 def_bool y
540 prompt "s390 architectural random number generation API"
541 help
542 Enable the s390 architectural random number generation API
543 to provide random data for all consumers within the Linux
544 kernel.
545
546 When enabled the arch_random_* functions declared in linux/random.h
547 are implemented. The implementation is based on the s390 CPACF
548 instruction subfunction TRNG which provides a real true random
549 number generator.
550
551 If unsure, say Y.
552
d768bd89
MS
553config KERNEL_NOBP
554 def_bool n
555 prompt "Enable modified branch prediction for the kernel by default"
556 help
557 If this option is selected the kernel will switch to a modified
558 branch prediction mode if the firmware interface is available.
559 The modified branch prediction mode improves the behaviour in
560 regard to speculative execution.
561
562 With the option enabled the kernel parameter "nobp=0" or "nospec"
563 can be used to run the kernel in the normal branch prediction mode.
564
565 With the option disabled the modified branch prediction mode is
566 enabled with the "nobp=1" kernel parameter.
567
568 If unsure, say N.
569
f19fbd5e
MS
570config EXPOLINE
571 def_bool n
572 prompt "Avoid speculative indirect branches in the kernel"
573 help
574 Compile the kernel with the expoline compiler options to guard
575 against kernel-to-user data leaks by avoiding speculative indirect
576 branches.
577 Requires a compiler with -mindirect-branch=thunk support for full
578 protection. The kernel may run slower.
579
580 If unsure, say N.
581
582choice
583 prompt "Expoline default"
584 depends on EXPOLINE
585 default EXPOLINE_FULL
586
587config EXPOLINE_OFF
588 bool "spectre_v2=off"
589
6e179d64 590config EXPOLINE_AUTO
f19fbd5e
MS
591 bool "spectre_v2=auto"
592
593config EXPOLINE_FULL
594 bool "spectre_v2=on"
595
596endchoice
597
843c48fd 598endmenu
1da177e4 599
843c48fd 600menu "Memory setup"
1d057720 601
843c48fd 602config ARCH_SPARSEMEM_ENABLE
6f9a3c33 603 def_bool y
843c48fd
JG
604 select SPARSEMEM_VMEMMAP_ENABLE
605 select SPARSEMEM_VMEMMAP
e65e1fc2 606
843c48fd
JG
607config ARCH_SPARSEMEM_DEFAULT
608 def_bool y
1da177e4 609
843c48fd
JG
610config ARCH_SELECT_MEMORY_MODEL
611 def_bool y
1da177e4 612
843c48fd
JG
613config ARCH_ENABLE_MEMORY_HOTPLUG
614 def_bool y if SPARSEMEM
0efa4703 615
843c48fd
JG
616config ARCH_ENABLE_MEMORY_HOTREMOVE
617 def_bool y
e37f50e1 618
ec66ad66
MS
619config ARCH_ENABLE_SPLIT_PMD_PTLOCK
620 def_bool y
ec66ad66 621
843c48fd
JG
622config FORCE_MAX_ZONEORDER
623 int
624 default "9"
f861e405 625
b8402b95
HC
626config MAX_PHYSMEM_BITS
627 int "Maximum size of supported physical memory in bits (42-53)"
628 range 42 53
629 default "46"
630 help
631 This option specifies the maximum supported size of physical memory
632 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
633 Increasing the number of bits also increases the kernel image size.
634 By default 46 bits (64TB) are supported.
635
1da177e4 636config PACK_STACK
6f9a3c33
MS
637 def_bool y
638 prompt "Pack kernel stack"
1da177e4
LT
639 help
640 This option enables the compiler option -mkernel-backchain if it
641 is available. If the option is available the compiler supports
642 the new stack layout which dramatically reduces the minimum stack
643 frame size. With an old compiler a non-leaf function needs a
644 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
645 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
646 and 24 byte on 64 bit.
647
648 Say Y if you are unsure.
649
1da177e4 650config CHECK_STACK
6f9a3c33
MS
651 def_bool y
652 prompt "Detect kernel stack overflow"
1da177e4
LT
653 help
654 This option enables the compiler option -mstack-guard and
655 -mstack-size if they are available. If the compiler supports them
656 it will emit additional code to each function prolog to trigger
657 an illegal operation if the kernel stack is about to overflow.
658
659 Say N if you are unsure.
660
661config STACK_GUARD
662 int "Size of the guard area (128-1024)"
663 range 128 1024
664 depends on CHECK_STACK
665 default "256"
666 help
667 This allows you to specify the size of the guard area at the lower
668 end of the kernel stack. If the kernel stack points into the guard
669 area on function entry an illegal operation is triggered. The size
670 needs to be a power of 2. Please keep in mind that the size of an
671 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
672 The minimum size for the stack guard should be 256 for 31 bit and
673 512 for 64 bit.
674
2c190da4 675config WARN_DYNAMIC_STACK
6f9a3c33 676 def_bool n
2c190da4 677 prompt "Emit compiler warnings for function with dynamic stack usage"
1da177e4 678 help
2c190da4
JG
679 This option enables the compiler option -mwarn-dynamicstack. If the
680 compiler supports this options generates warnings for functions
681 that dynamically allocate stack space using alloca.
1da177e4
LT
682
683 Say N if you are unsure.
684
843c48fd 685endmenu
3f22ab27 686
843c48fd 687menu "I/O subsystem"
1da177e4 688
1da177e4 689config QDIO
6f9a3c33
MS
690 def_tristate y
691 prompt "QDIO support"
1da177e4 692 ---help---
8129ee16 693 This driver provides the Queued Direct I/O base support for
efca13bc 694 IBM System z.
1da177e4
LT
695
696 To compile this driver as a module, choose M here: the
697 module will be called qdio.
698
699 If unsure, say Y.
700
c8717a3d
JG
701menuconfig PCI
702 bool "PCI support"
c8717a3d 703 select PCI_MSI
a4ce5a48 704 select IOMMU_HELPER
8128f23c 705 select IOMMU_SUPPORT
f616ab59 706 select NEED_DMA_MAP_STATE
86596f0a 707 select NEED_SG_DMA_LENGTH
a4ce5a48 708
c8717a3d
JG
709 help
710 Enable PCI support.
711
712if PCI
713
714config PCI_NR_FUNCTIONS
715 int "Maximum number of PCI functions (1-4096)"
716 range 1 4096
b18601b0 717 default "128"
c8717a3d
JG
718 help
719 This allows you to specify the maximum number of PCI functions which
720 this kernel will support.
721
722source "drivers/pci/Kconfig"
c8717a3d
JG
723
724endif # PCI
725
726config PCI_DOMAINS
727 def_bool PCI
728
729config HAS_IOMEM
730 def_bool PCI
731
9d92a7e1 732config CHSC_SCH
d9c11b1e 733 def_tristate m
6f9a3c33 734 prompt "Support for CHSC subchannels"
9d92a7e1
CH
735 help
736 This driver allows usage of CHSC subchannels. A CHSC subchannel
737 is usually present on LPAR only.
738 The driver creates a device /dev/chsc, which may be used to
739 obtain I/O configuration information about the machine and
740 to issue asynchronous chsc commands (DANGEROUS).
741 You will usually only want to use this interface on a special
742 LPAR designated for system management.
743
744 To compile this driver as a module, choose M here: the
745 module will be called chsc_sch.
746
747 If unsure, say N.
748
1d1c8f78
SO
749config SCM_BUS
750 def_bool y
1d1c8f78
SO
751 prompt "SCM bus driver"
752 help
753 Bus driver for Storage Class Memory.
754
eadb86ab
SO
755config EADM_SCH
756 def_tristate m
757 prompt "Support for EADM subchannels"
758 depends on SCM_BUS
759 help
760 This driver allows usage of EADM subchannels. EADM subchannels act
761 as a communication vehicle for SCM increments.
762
763 To compile this driver as a module, choose M here: the
764 module will be called eadm_sch.
765
63f1934d
DJS
766config VFIO_CCW
767 def_tristate n
768 prompt "Support for VFIO-CCW subchannels"
84cd8fc4 769 depends on S390_CCW_IOMMU && VFIO_MDEV
63f1934d
DJS
770 help
771 This driver allows usage of I/O subchannels via VFIO-CCW.
772
773 To compile this driver as a module, choose M here: the
774 module will be called vfio_ccw.
775
843c48fd
JG
776endmenu
777
778menu "Dump support"
779
780config CRASH_DUMP
781 bool "kernel crash dumps"
5a79859a 782 depends on SMP
843c48fd
JG
783 select KEXEC
784 help
785 Generate crash dump after being started by kexec.
786 Crash dump kernels are loaded in the main kernel with kexec-tools
787 into a specially reserved region and then later executed after
788 a crash by kdump/kexec.
843c48fd 789 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
bf28a597
MH
790 This option also enables s390 zfcpdump.
791 See also <file:Documentation/s390/zfcpdump.txt>
843c48fd
JG
792
793endmenu
794
843c48fd
JG
795config SECCOMP
796 def_bool y
797 prompt "Enable seccomp to safely compute untrusted bytecode"
798 depends on PROC_FS
799 help
800 This kernel feature is useful for number crunching applications
801 that may need to compute untrusted bytecode during their
802 execution. By using pipes or other transports made available to
803 the process as file descriptors supporting the read/write
804 syscalls, it's possible to isolate those applications in
805 their own address space using seccomp. Once seccomp is
806 enabled via /proc/<pid>/seccomp, it cannot be disabled
807 and the task is only allowed to execute a few safe syscalls
808 defined by each seccomp mode.
809
810 If unsure, say Y.
811
843c48fd
JG
812menu "Power Management"
813
814config ARCH_HIBERNATION_POSSIBLE
5a79859a 815 def_bool y
843c48fd
JG
816
817source "kernel/power/Kconfig"
818
819endmenu
820
843c48fd
JG
821config PCMCIA
822 def_bool n
823
824config CCW
825 def_bool y
826
b6ef86e9
UB
827config HAVE_PNETID
828 tristate
829 default (SMC || CCWGROUP)
830
843c48fd 831menu "Virtualization"
684de39b 832
1da177e4 833config PFAULT
6f9a3c33
MS
834 def_bool y
835 prompt "Pseudo page fault support"
1da177e4
LT
836 help
837 Select this option, if you want to use PFAULT pseudo page fault
838 handling under VM. If running native or in LPAR, this option
839 has no effect. If your VM does not support PFAULT, PAGEEX
840 pseudo page fault handling will be used.
841 Note that VM 4.2 supports PFAULT but has a bug in its
842 implementation that causes some problems.
843 Everybody who wants to run Linux under VM != VM4.2 should select
844 this option.
845
1da177e4 846config CMM
6f9a3c33
MS
847 def_tristate n
848 prompt "Cooperative memory management"
1da177e4
LT
849 help
850 Select this option, if you want to enable the kernel interface
851 to reduce the memory size of the system. This is accomplished
852 by allocating pages of memory and put them "on hold". This only
853 makes sense for a system running under VM where the unused pages
854 will be reused by VM for other guest systems. The interface
855 allows an external monitor to balance memory of many systems.
856 Everybody who wants to run Linux under VM should select this
857 option.
858
1da177e4 859config CMM_IUCV
6f9a3c33
MS
860 def_bool y
861 prompt "IUCV special message interface to cooperative memory management"
1da177e4
LT
862 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
863 help
864 Select this option to enable the special message interface to
865 the cooperative memory management.
866
1da177e4 867config APPLDATA_BASE
6f9a3c33
MS
868 def_bool n
869 prompt "Linux - VM Monitor Stream, base infrastructure"
c185b783 870 depends on PROC_FS
1da177e4
LT
871 help
872 This provides a kernel interface for creating and updating z/VM APPLDATA
873 monitor records. The monitor records are updated at certain time
874 intervals, once the timer is started.
875 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
876 i.e. enables or disables monitoring on the Linux side.
877 A custom interval value (in seconds) can be written to
878 /proc/appldata/interval.
879
880 Defaults are 60 seconds interval and timer off.
881 The /proc entries can also be read from, showing the current settings.
882
883config APPLDATA_MEM
6f9a3c33
MS
884 def_tristate m
885 prompt "Monitor memory management statistics"
62fb2ba3 886 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
1da177e4
LT
887 help
888 This provides memory management related data to the Linux - VM Monitor
889 Stream, like paging/swapping rate, memory utilisation, etc.
890 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
891 APPLDATA monitor record, i.e. enables or disables monitoring this record
892 on the z/VM side.
893
894 Default is disabled.
895 The /proc entry can also be read from, showing the current settings.
896
897 This can also be compiled as a module, which will be called
898 appldata_mem.o.
899
900config APPLDATA_OS
6f9a3c33
MS
901 def_tristate m
902 prompt "Monitor OS statistics"
1da177e4
LT
903 depends on APPLDATA_BASE
904 help
905 This provides OS related data to the Linux - VM Monitor Stream, like
906 CPU utilisation, etc.
907 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
908 APPLDATA monitor record, i.e. enables or disables monitoring this record
909 on the z/VM side.
910
911 Default is disabled.
912 This can also be compiled as a module, which will be called
913 appldata_os.o.
914
915config APPLDATA_NET_SUM
6f9a3c33
MS
916 def_tristate m
917 prompt "Monitor overall network statistics"
70193af9 918 depends on APPLDATA_BASE && NET
1da177e4
LT
919 help
920 This provides network related data to the Linux - VM Monitor Stream,
921 currently there is only a total sum of network I/O statistics, no
922 per-interface data.
923 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
924 APPLDATA monitor record, i.e. enables or disables monitoring this record
925 on the z/VM side.
926
927 Default is disabled.
928 This can also be compiled as a module, which will be called
929 appldata_net_sum.o.
930
24bbb1fa 931config S390_HYPFS_FS
6f9a3c33
MS
932 def_bool y
933 prompt "s390 hypervisor file system support"
24bbb1fa 934 select SYS_HYPERVISOR
24bbb1fa
MH
935 help
936 This is a virtual file system intended to provide accounting
937 information in an s390 hypervisor environment.
938
843c48fd 939source "arch/s390/kvm/Kconfig"
411ed322 940
fa587743 941config S390_GUEST
6f9a3c33 942 def_bool y
510cf5a6 943 prompt "s390 support for virtio devices"
79b6f7fb 944 select TTY
80629b0b 945 select VIRTUALIZATION
fa587743 946 select VIRTIO
faeba830 947 select VIRTIO_CONSOLE
fa587743 948 help
bdd1fc27
CH
949 Enabling this option adds support for virtio based paravirtual device
950 drivers on s390.
1da177e4 951
20766c08 952 Select this option if you want to run the kernel as a guest under
bdd1fc27 953 the KVM hypervisor.
155af2f9
HJP
954
955endmenu