xref: /linux/arch/s390/Kconfig (revision c574fb2ed7c96f87fc0e5295e910e646a7ee4dfa)
1# SPDX-License-Identifier: GPL-2.0
2config MMU
3	def_bool y
4
5config CPU_BIG_ENDIAN
6	def_bool y
7
8config LOCKDEP_SUPPORT
9	def_bool y
10
11config STACKTRACE_SUPPORT
12	def_bool y
13
14config ARCH_HAS_ILOG2_U32
15	def_bool n
16
17config ARCH_HAS_ILOG2_U64
18	def_bool n
19
20config ARCH_PROC_KCORE_TEXT
21	def_bool y
22
23config GENERIC_HWEIGHT
24	def_bool !HAVE_MARCH_Z196_FEATURES
25
26config GENERIC_BUG
27	def_bool y if BUG
28
29config GENERIC_BUG_RELATIVE_POINTERS
30	def_bool y
31
32config GENERIC_LOCKBREAK
33	def_bool y if PREEMPTION
34
35config PGSTE
36	def_bool y if KVM
37
38config AUDIT_ARCH
39	def_bool y
40
41config NO_IOPORT_MAP
42	def_bool y
43
44config ARCH_SUPPORTS_UPROBES
45	def_bool y
46
47config KASAN_SHADOW_OFFSET
48	hex
49	depends on KASAN
50	default 0x1C000000000000
51
52config CC_HAS_BUILTIN_FFS
53	def_bool !(CC_IS_GCC && GCC_VERSION < 160000)
54	help
55	  GCC versions before 16.0.0 generate library calls to ffs()
56	  for __builtin_ffs() even when __has_builtin(__builtin_ffs)
57	  is true.
58
59config CC_ASM_FLAG_OUTPUT_BROKEN
60	def_bool CC_IS_GCC && GCC_VERSION < 140200
61	help
62	  GCC versions before 14.2.0 may die with an internal
63	  compiler error in some configurations if flag output
64	  operands are used within inline assemblies.
65
66config CC_HAS_ASM_AOR_FORMAT_FLAGS
67	def_bool !(CC_IS_CLANG && CLANG_VERSION < 190100)
68	help
69	  Clang versions before 19.1.0 do not support A,
70	  O, and R inline assembly format flags.
71
72config S390
73	def_bool y
74	#
75	# Note: keep this list sorted alphabetically
76	#
77	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
78	select ALTERNATE_USER_ADDRESS_SPACE
79	select ARCH_32BIT_USTAT_F_TINODE
80	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
81	select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM
82	select ARCH_ENABLE_MEMORY_HOTREMOVE
83	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
84	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
85	select ARCH_HAS_CPU_FINALIZE_INIT
86	select ARCH_HAS_CURRENT_STACK_POINTER
87	select ARCH_HAS_DEBUG_VIRTUAL
88	select ARCH_HAS_DEBUG_VM_PGTABLE
89	select ARCH_HAS_DEBUG_WX
90	select ARCH_HAS_DEVMEM_IS_ALLOWED
91	select ARCH_HAS_DMA_OPS if PCI
92	select ARCH_HAS_ELF_RANDOMIZE
93	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
94	select ARCH_HAS_FORTIFY_SOURCE
95	select ARCH_HAS_GCOV_PROFILE_ALL
96	select ARCH_HAS_GIGANTIC_PAGE
97	select ARCH_HAS_KCOV
98	select ARCH_HAS_MEMBARRIER_SYNC_CORE
99	select ARCH_HAS_MEM_ENCRYPT
100	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
101	select ARCH_HAS_PREEMPT_LAZY
102	select ARCH_HAS_PTDUMP
103	select ARCH_HAS_PTE_SPECIAL
104	select ARCH_HAS_SCALED_CPUTIME
105	select ARCH_HAS_SET_DIRECT_MAP
106	select ARCH_HAS_SET_MEMORY
107	select ARCH_HAS_STRICT_KERNEL_RWX
108	select ARCH_HAS_STRICT_MODULE_RWX
109	select ARCH_HAS_SYSCALL_WRAPPER
110	select ARCH_HAS_UBSAN
111	select ARCH_HAS_VDSO_TIME_DATA
112	select ARCH_HAVE_NMI_SAFE_CMPXCHG
113	select ARCH_HAVE_TRACE_MMIO_ACCESS
114	select ARCH_INLINE_READ_LOCK
115	select ARCH_INLINE_READ_LOCK_BH
116	select ARCH_INLINE_READ_LOCK_IRQ
117	select ARCH_INLINE_READ_LOCK_IRQSAVE
118	select ARCH_INLINE_READ_TRYLOCK
119	select ARCH_INLINE_READ_UNLOCK
120	select ARCH_INLINE_READ_UNLOCK_BH
121	select ARCH_INLINE_READ_UNLOCK_IRQ
122	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
123	select ARCH_INLINE_SPIN_LOCK
124	select ARCH_INLINE_SPIN_LOCK_BH
125	select ARCH_INLINE_SPIN_LOCK_IRQ
126	select ARCH_INLINE_SPIN_LOCK_IRQSAVE
127	select ARCH_INLINE_SPIN_TRYLOCK
128	select ARCH_INLINE_SPIN_TRYLOCK_BH
129	select ARCH_INLINE_SPIN_UNLOCK
130	select ARCH_INLINE_SPIN_UNLOCK_BH
131	select ARCH_INLINE_SPIN_UNLOCK_IRQ
132	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
133	select ARCH_INLINE_WRITE_LOCK
134	select ARCH_INLINE_WRITE_LOCK_BH
135	select ARCH_INLINE_WRITE_LOCK_IRQ
136	select ARCH_INLINE_WRITE_LOCK_IRQSAVE
137	select ARCH_INLINE_WRITE_TRYLOCK
138	select ARCH_INLINE_WRITE_UNLOCK
139	select ARCH_INLINE_WRITE_UNLOCK_BH
140	select ARCH_INLINE_WRITE_UNLOCK_IRQ
141	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
142	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
143	select ARCH_MODULE_NEEDS_WEAK_PER_CPU
144	select ARCH_STACKWALK
145	select ARCH_SUPPORTS_ATOMIC_RMW
146	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
147	select ARCH_SUPPORTS_HUGETLBFS
148	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG
149	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
150	select ARCH_SUPPORTS_NUMA_BALANCING
151	select ARCH_SUPPORTS_PER_VMA_LOCK
152	select ARCH_USE_BUILTIN_BSWAP
153	select ARCH_USE_CMPXCHG_LOCKREF
154	select ARCH_USE_SYM_ANNOTATIONS
155	select ARCH_WANTS_NO_INSTR
156	select ARCH_WANT_DEFAULT_BPF_JIT
157	select ARCH_WANT_IPC_PARSE_VERSION
158	select ARCH_WANT_IRQS_OFF_ACTIVATE_MM
159	select ARCH_WANT_KERNEL_PMD_MKWRITE
160	select ARCH_WANT_LD_ORPHAN_WARN
161	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
162	select ARCH_WANTS_THP_SWAP
163	select BUILDTIME_TABLE_SORT
164	select CLONE_BACKWARDS2
165	select DCACHE_WORD_ACCESS if !KMSAN
166	select DYNAMIC_FTRACE if FUNCTION_TRACER
167	select FUNCTION_ALIGNMENT_8B if CC_IS_GCC
168	select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC
169	select GENERIC_ALLOCATOR
170	select GENERIC_CPU_DEVICES
171	select GENERIC_CPU_AUTOPROBE
172	select GENERIC_CPU_VULNERABILITIES
173	select GENERIC_ENTRY
174	select GENERIC_GETTIMEOFDAY
175	select GENERIC_SMP_IDLE_THREAD
176	select GENERIC_TIME_VSYSCALL
177	select GENERIC_VDSO_DATA_STORE
178	select GENERIC_VDSO_TIME_NS
179	select GENERIC_IOREMAP if PCI
180	select HAVE_ALIGNED_STRUCT_PAGE
181	select HAVE_ARCH_AUDITSYSCALL
182	select HAVE_ARCH_JUMP_LABEL
183	select HAVE_ARCH_JUMP_LABEL_RELATIVE
184	select HAVE_ARCH_KASAN
185	select HAVE_ARCH_KASAN_VMALLOC
186	select HAVE_ARCH_KCSAN
187	select HAVE_ARCH_KMSAN
188	select HAVE_ARCH_KFENCE
189	select HAVE_ARCH_KSTACK_ERASE
190	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
191	select HAVE_ARCH_SECCOMP_FILTER
192	select HAVE_ARCH_SOFT_DIRTY
193	select HAVE_ARCH_TRACEHOOK
194	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
195	select HAVE_ARCH_VMAP_STACK
196	select HAVE_ASM_MODVERSIONS
197	select HAVE_BUILDTIME_MCOUNT_SORT
198	select HAVE_CMPXCHG_DOUBLE
199	select HAVE_CMPXCHG_LOCAL
200	select HAVE_DEBUG_KMEMLEAK
201	select HAVE_DMA_CONTIGUOUS
202	select HAVE_DYNAMIC_FTRACE
203	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
204	select HAVE_FTRACE_REGS_HAVING_PT_REGS
205	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
206	select HAVE_DYNAMIC_FTRACE_WITH_REGS
207	select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES
208	select HAVE_EFFICIENT_UNALIGNED_ACCESS
209	select HAVE_GENERIC_TIF_BITS
210	select HAVE_GUP_FAST
211	select HAVE_FENTRY
212	select HAVE_FTRACE_GRAPH_FUNC
213	select HAVE_FUNCTION_ARG_ACCESS_API
214	select HAVE_FUNCTION_ERROR_INJECTION
215	select HAVE_FUNCTION_GRAPH_FREGS
216	select HAVE_FUNCTION_GRAPH_TRACER
217	select HAVE_FUNCTION_TRACER
218	select HAVE_GCC_PLUGINS
219	select HAVE_GENERIC_VDSO
220	select HAVE_IOREMAP_PROT if PCI
221	select HAVE_KERNEL_BZIP2
222	select HAVE_KERNEL_GZIP
223	select HAVE_KERNEL_LZ4
224	select HAVE_KERNEL_LZMA
225	select HAVE_KERNEL_LZO
226	select HAVE_KERNEL_UNCOMPRESSED
227	select HAVE_KERNEL_XZ
228	select HAVE_KERNEL_ZSTD
229	select HAVE_KPROBES
230	select HAVE_KPROBES_ON_FTRACE
231	select HAVE_KRETPROBES
232	select HAVE_LIVEPATCH
233	select HAVE_MEMBLOCK_PHYS_MAP
234	select HAVE_MOD_ARCH_SPECIFIC
235	select HAVE_NMI
236	select HAVE_NOP_MCOUNT
237	select HAVE_PAGE_SIZE_4KB
238	select HAVE_PCI
239	select HAVE_PERF_EVENTS
240	select HAVE_PERF_REGS
241	select HAVE_PERF_USER_STACK_DUMP
242	select HAVE_PREEMPT_DYNAMIC_KEY
243	select HAVE_REGS_AND_STACK_ACCESS_API
244	select HAVE_RELIABLE_STACKTRACE
245	select HAVE_RETHOOK
246	select HAVE_RSEQ
247	select HAVE_SAMPLE_FTRACE_DIRECT
248	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
249	select HAVE_SETUP_PER_CPU_AREA
250	select HAVE_SOFTIRQ_ON_OWN_STACK
251	select HAVE_SYSCALL_TRACEPOINTS
252	select HAVE_VIRT_CPU_ACCOUNTING
253	select HAVE_VIRT_CPU_ACCOUNTING_IDLE
254	select HOTPLUG_SMT
255	select IOMMU_HELPER		if PCI
256	select IOMMU_SUPPORT		if PCI
257	select KASAN_VMALLOC if KASAN
258	select LOCK_MM_AND_FIND_VMA
259	select MMU_GATHER_MERGE_VMAS
260	select MMU_GATHER_NO_GATHER
261	select MMU_GATHER_RCU_TABLE_FREE
262	select MODULES_USE_ELF_RELA
263	select NEED_DMA_MAP_STATE	if PCI
264	select NEED_PER_CPU_EMBED_FIRST_CHUNK
265	select NEED_PROC_VMCORE_DEVICE_RAM if PROC_VMCORE
266	select NEED_SG_DMA_LENGTH	if PCI
267	select OLD_SIGACTION
268	select OLD_SIGSUSPEND3
269	select PCI_DOMAINS		if PCI
270	select PCI_MSI			if PCI
271	select PCI_MSI_ARCH_FALLBACKS	if PCI_MSI
272	select PCI_QUIRKS		if PCI
273	select SPARSE_IRQ
274	select SWIOTLB
275	select SYSCTL_EXCEPTION_TRACE
276	select THREAD_INFO_IN_TASK
277	select TRACE_IRQFLAGS_SUPPORT
278	select TTY
279	select USER_STACKTRACE_SUPPORT
280	select VDSO_GETRANDOM
281	select VIRT_CPU_ACCOUNTING
282	select VMAP_STACK
283	select ZONE_DMA
284	# Note: keep the above list sorted alphabetically
285
286config SCHED_OMIT_FRAME_POINTER
287	def_bool y
288
289config PGTABLE_LEVELS
290	int
291	default 5
292
293source "kernel/livepatch/Kconfig"
294
295config ARCH_SUPPORTS_KEXEC
296	def_bool y
297
298config ARCH_SUPPORTS_KEXEC_FILE
299	def_bool y
300
301config ARCH_SUPPORTS_KEXEC_SIG
302	def_bool MODULE_SIG_FORMAT
303
304config ARCH_SUPPORTS_KEXEC_PURGATORY
305	def_bool y
306
307config ARCH_SUPPORTS_CRASH_DUMP
308	def_bool y
309	help
310	  Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this.
311	  This option also enables s390 zfcpdump.
312	  See also <file:Documentation/arch/s390/zfcpdump.rst>
313
314config ARCH_DEFAULT_CRASH_DUMP
315	def_bool y
316
317menu "Processor type and features"
318
319config HAVE_MARCH_Z10_FEATURES
320	def_bool n
321
322config HAVE_MARCH_Z196_FEATURES
323	def_bool n
324	select HAVE_MARCH_Z10_FEATURES
325
326config HAVE_MARCH_ZEC12_FEATURES
327	def_bool n
328	select HAVE_MARCH_Z196_FEATURES
329
330config HAVE_MARCH_Z13_FEATURES
331	def_bool n
332	select HAVE_MARCH_ZEC12_FEATURES
333
334config HAVE_MARCH_Z14_FEATURES
335	def_bool n
336	select HAVE_MARCH_Z13_FEATURES
337
338config HAVE_MARCH_Z15_FEATURES
339	def_bool n
340	select HAVE_MARCH_Z14_FEATURES
341
342config HAVE_MARCH_Z16_FEATURES
343	def_bool n
344	select HAVE_MARCH_Z15_FEATURES
345
346config HAVE_MARCH_Z17_FEATURES
347	def_bool n
348	select HAVE_MARCH_Z16_FEATURES
349
350choice
351	prompt "Processor type"
352	default MARCH_Z196
353
354config MARCH_Z10
355	bool "IBM System z10"
356	select HAVE_MARCH_Z10_FEATURES
357	depends on $(cc-option,-march=z10)
358	help
359	  Select this to enable optimizations for IBM System z10 (2097 and 2098
360	  series). This is the oldest machine generation currently supported.
361
362config MARCH_Z196
363	bool "IBM zEnterprise 114 and 196"
364	select HAVE_MARCH_Z196_FEATURES
365	depends on $(cc-option,-march=z196)
366	help
367	  Select this to enable optimizations for IBM zEnterprise 114 and 196
368	  (2818 and 2817 series). The kernel will be slightly faster but will
369	  not work on older machines.
370
371config MARCH_ZEC12
372	bool "IBM zBC12 and zEC12"
373	select HAVE_MARCH_ZEC12_FEATURES
374	depends on $(cc-option,-march=zEC12)
375	help
376	  Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
377	  2827 series). The kernel will be slightly faster but will not work on
378	  older machines.
379
380config MARCH_Z13
381	bool "IBM z13s and z13"
382	select HAVE_MARCH_Z13_FEATURES
383	depends on $(cc-option,-march=z13)
384	help
385	  Select this to enable optimizations for IBM z13s and z13 (2965 and
386	  2964 series). The kernel will be slightly faster but will not work on
387	  older machines.
388
389config MARCH_Z14
390	bool "IBM z14 ZR1 and z14"
391	select HAVE_MARCH_Z14_FEATURES
392	depends on $(cc-option,-march=z14)
393	help
394	  Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
395	  and 3906 series). The kernel will be slightly faster but will not
396	  work on older machines.
397
398config MARCH_Z15
399	bool "IBM z15"
400	select HAVE_MARCH_Z15_FEATURES
401	depends on $(cc-option,-march=z15)
402	help
403	  Select this to enable optimizations for IBM z15 (8562
404	  and 8561 series). The kernel will be slightly faster but will not
405	  work on older machines.
406
407config MARCH_Z16
408	bool "IBM z16"
409	select HAVE_MARCH_Z16_FEATURES
410	depends on $(cc-option,-march=z16)
411	help
412	  Select this to enable optimizations for IBM z16 (3931 and
413	  3932 series).
414
415config MARCH_Z17
416	bool "IBM z17"
417	select HAVE_MARCH_Z17_FEATURES
418	depends on $(cc-option,-march=z17)
419	help
420	  Select this to enable optimizations for IBM z17 (9175 and
421	  9176 series).
422
423endchoice
424
425config MARCH_Z10_TUNE
426	def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
427
428config MARCH_Z196_TUNE
429	def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
430
431config MARCH_ZEC12_TUNE
432	def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
433
434config MARCH_Z13_TUNE
435	def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
436
437config MARCH_Z14_TUNE
438	def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
439
440config MARCH_Z15_TUNE
441	def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
442
443config MARCH_Z16_TUNE
444	def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT
445
446config MARCH_Z17_TUNE
447	def_bool TUNE_Z17 || MARCH_Z17 && TUNE_DEFAULT
448
449choice
450	prompt "Tune code generation"
451	default TUNE_DEFAULT
452	help
453	  Cause the compiler to tune (-mtune) the generated code for a machine.
454	  This will make the code run faster on the selected machine but
455	  somewhat slower on other machines.
456	  This option only changes how the compiler emits instructions, not the
457	  selection of instructions itself, so the resulting kernel will run on
458	  all other machines.
459
460config TUNE_DEFAULT
461	bool "Default"
462	help
463	  Tune the generated code for the target processor for which the kernel
464	  will be compiled.
465
466config TUNE_Z10
467	bool "IBM System z10"
468
469config TUNE_Z196
470	bool "IBM zEnterprise 114 and 196"
471	depends on $(cc-option,-mtune=z196)
472
473config TUNE_ZEC12
474	bool "IBM zBC12 and zEC12"
475	depends on $(cc-option,-mtune=zEC12)
476
477config TUNE_Z13
478	bool "IBM z13s and z13"
479	depends on $(cc-option,-mtune=z13)
480
481config TUNE_Z14
482	bool "IBM z14 ZR1 and z14"
483	depends on $(cc-option,-mtune=z14)
484
485config TUNE_Z15
486	bool "IBM z15"
487	depends on $(cc-option,-mtune=z15)
488
489config TUNE_Z16
490	bool "IBM z16"
491	depends on $(cc-option,-mtune=z16)
492
493config TUNE_Z17
494	bool "IBM z17"
495	depends on $(cc-option,-mtune=z17)
496
497endchoice
498
499config 64BIT
500	def_bool y
501
502config COMMAND_LINE_SIZE
503	int "Maximum size of kernel command line"
504	default 4096
505	range 896 1048576
506	help
507	  This allows you to specify the maximum length of the kernel command
508	  line.
509
510config COMPAT
511	def_bool n
512	prompt "Kernel support for 31 bit emulation"
513	select ARCH_WANT_OLD_COMPAT_IPC
514	select COMPAT_OLD_SIGACTION
515	select HAVE_UID16
516	depends on MULTIUSER
517	depends on !CC_IS_CLANG && !LD_IS_LLD
518	help
519	  Select this option if you want to enable your system kernel to
520	  handle system-calls from ELF binaries for 31 bit ESA.  This option
521	  (and some other stuff like libraries and such) is needed for
522	  executing 31 bit applications.
523
524	  If unsure say N.
525
526config SMP
527	def_bool y
528
529config NR_CPUS
530	int "Maximum number of CPUs (2-512)"
531	range 2 512
532	default "64"
533	help
534	  This allows you to specify the maximum number of CPUs which this
535	  kernel will support. The maximum supported value is 512 and the
536	  minimum value which makes sense is 2.
537
538	  This is purely to save memory - each supported CPU adds
539	  approximately sixteen kilobytes to the kernel image.
540
541config HOTPLUG_CPU
542	def_bool y
543
544config NUMA
545	bool "NUMA support"
546	depends on SCHED_TOPOLOGY
547	default n
548	help
549	  Enable NUMA support
550
551	  This option adds NUMA support to the kernel.
552
553config NODES_SHIFT
554	int
555	depends on NUMA
556	default "1"
557
558config SCHED_TOPOLOGY
559	def_bool y
560	prompt "Topology scheduler support"
561	select ARCH_SUPPORTS_SCHED_SMT
562	select ARCH_SUPPORTS_SCHED_MC
563	select SCHED_SMT
564	select SCHED_MC
565	help
566	  Topology scheduler support improves the CPU scheduler's decision
567	  making when dealing with machines that have multi-threading,
568	  multiple cores or multiple books.
569
570config SCHED_TOPOLOGY_VERTICAL
571	def_bool y
572	bool "Use vertical CPU polarization by default"
573	depends on SCHED_TOPOLOGY
574	help
575	  Use vertical CPU polarization by default if available.
576	  The default CPU polarization is horizontal.
577
578config HIPERDISPATCH_ON
579	def_bool y
580	bool "Use hiperdispatch on vertical polarization by default"
581	depends on SCHED_TOPOLOGY
582	depends on PROC_SYSCTL
583	help
584	  Hiperdispatch aims to improve the CPU scheduler's decision
585	  making when using vertical polarization by adjusting CPU
586	  capacities dynamically. Set this option to use hiperdispatch
587	  on vertical polarization by default. This can be overwritten
588	  by sysctl's s390.hiperdispatch attribute later on.
589
590source "kernel/Kconfig.hz"
591
592config CERT_STORE
593	bool "Get user certificates via DIAG320"
594	depends on KEYS
595	select CRYPTO_LIB_SHA256
596	help
597	  Enable this option if you want to access user-provided secure boot
598	  certificates via DIAG 0x320.
599
600	  These certificates will be made available via the keyring named
601	  'cert_store'.
602
603config KERNEL_NOBP
604	def_bool n
605	prompt "Enable modified branch prediction for the kernel by default"
606	help
607	  If this option is selected the kernel will switch to a modified
608	  branch prediction mode if the firmware interface is available.
609	  The modified branch prediction mode improves the behaviour in
610	  regard to speculative execution.
611
612	  With the option enabled the kernel parameter "nobp=0" or "nospec"
613	  can be used to run the kernel in the normal branch prediction mode.
614
615	  With the option disabled the modified branch prediction mode is
616	  enabled with the "nobp=1" kernel parameter.
617
618	  If unsure, say N.
619
620config EXPOLINE
621	def_bool n
622	depends on $(cc-option,-mindirect-branch=thunk)
623	prompt "Avoid speculative indirect branches in the kernel"
624	help
625	  Compile the kernel with the expoline compiler options to guard
626	  against kernel-to-user data leaks by avoiding speculative indirect
627	  branches.
628	  Requires a compiler with -mindirect-branch=thunk support for full
629	  protection. The kernel may run slower.
630
631	  If unsure, say N.
632
633config EXPOLINE_EXTERN
634	def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \
635		 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))
636	help
637	  Generate expolines as external functions if the compiler supports it.
638	  This option is required for some tooling like kpatch, if expolines
639	  are enabled. The kernel is compiled with
640	  -mindirect-branch=thunk-extern, which requires a newer compiler.
641
642choice
643	prompt "Expoline default"
644	depends on EXPOLINE
645	default EXPOLINE_FULL
646
647config EXPOLINE_OFF
648	bool "spectre_v2=off"
649
650config EXPOLINE_AUTO
651	bool "spectre_v2=auto"
652
653config EXPOLINE_FULL
654	bool "spectre_v2=on"
655
656endchoice
657
658config RELOCATABLE
659	def_bool y
660	select ARCH_VMLINUX_NEEDS_RELOCS
661	help
662	  This builds a kernel image that retains relocation information
663	  so it can be loaded at an arbitrary address.
664	  The relocations make the kernel image about 15% larger (compressed
665	  10%), but are discarded at runtime.
666	  Note: this option exists only for documentation purposes, please do
667	  not remove it.
668
669config RANDOMIZE_BASE
670	bool "Randomize the address of the kernel image (KASLR)"
671	default y
672	help
673	  In support of Kernel Address Space Layout Randomization (KASLR),
674	  this randomizes the address at which the kernel image is loaded,
675	  as a security feature that deters exploit attempts relying on
676	  knowledge of the location of kernel internals.
677
678config RANDOMIZE_IDENTITY_BASE
679	bool "Randomize the address of the identity mapping base"
680	depends on RANDOMIZE_BASE
681	default DEBUG_VM
682	help
683	  The identity mapping base address is pinned to zero by default.
684	  Allow randomization of that base to expose otherwise missed
685	  notion of physical and virtual addresses of data structures.
686	  That does not have any impact on the base address at which the
687	  kernel image is loaded.
688
689	  If unsure, say N
690
691config KERNEL_IMAGE_BASE
692	hex "Kernel image base address"
693	range 0x100000 0x1FFFFFE0000000 if !KASAN
694	range 0x100000 0x1BFFFFE0000000 if KASAN
695	default 0x3FFE0000000 if !KASAN
696	default 0x7FFFE0000000 if KASAN
697	help
698	  This is the address at which the kernel image is loaded in case
699	  Kernel Address Space Layout Randomization (KASLR) is disabled.
700
701	  In case the Protected virtualization guest support is enabled the
702	  Ultravisor imposes a virtual address limit. If the value of this
703	  option leads to the kernel image exceeding the Ultravisor limit,
704	  this option is ignored and the image is loaded below the limit.
705
706	  If the value of this option leads to the kernel image overlapping
707	  the virtual memory where other data structures are located, this
708	  option is ignored and the image is loaded above the structures.
709
710endmenu
711
712menu "Memory setup"
713
714config ARCH_SPARSEMEM_ENABLE
715	def_bool y
716	select SPARSEMEM_VMEMMAP_ENABLE
717	select SPARSEMEM_VMEMMAP
718
719config ARCH_SPARSEMEM_DEFAULT
720	def_bool y
721
722config MAX_PHYSMEM_BITS
723	int "Maximum size of supported physical memory in bits (42-53)"
724	range 42 53
725	default "46"
726	help
727	  This option specifies the maximum supported size of physical memory
728	  in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
729	  Increasing the number of bits also increases the kernel image size.
730	  By default 46 bits (64TB) are supported.
731
732endmenu
733
734menu "I/O subsystem"
735
736config QDIO
737	def_tristate y
738	prompt "QDIO support"
739	help
740	  This driver provides the Queued Direct I/O base support for
741	  IBM System z.
742
743	  To compile this driver as a module, choose M here: the
744	  module will be called qdio.
745
746	  If unsure, say Y.
747
748if PCI
749
750config PCI_NR_FUNCTIONS
751	int "Maximum number of PCI functions (1-4096)"
752	range 1 4096
753	default "512"
754	help
755	  This allows you to specify the maximum number of PCI functions which
756	  this kernel will support.
757
758endif # PCI
759
760config HAS_IOMEM
761	def_bool PCI
762
763config CHSC_SCH
764	def_tristate m
765	prompt "Support for CHSC subchannels"
766	help
767	  This driver allows usage of CHSC subchannels. A CHSC subchannel
768	  is usually present on LPAR only.
769	  The driver creates a device /dev/chsc, which may be used to
770	  obtain I/O configuration information about the machine and
771	  to issue asynchronous chsc commands (DANGEROUS).
772	  You will usually only want to use this interface on a special
773	  LPAR designated for system management.
774
775	  To compile this driver as a module, choose M here: the
776	  module will be called chsc_sch.
777
778	  If unsure, say N.
779
780config SCM_BUS
781	def_bool y
782	prompt "SCM bus driver"
783	help
784	  Bus driver for Storage Class Memory.
785
786config EADM_SCH
787	def_tristate m
788	prompt "Support for EADM subchannels"
789	depends on SCM_BUS
790	help
791	  This driver allows usage of EADM subchannels. EADM subchannels act
792	  as a communication vehicle for SCM increments.
793
794	  To compile this driver as a module, choose M here: the
795	  module will be called eadm_sch.
796
797config AP
798	def_tristate y
799	prompt "Support for Adjunct Processors (ap)"
800	help
801	  This driver allows usage to Adjunct Processor (AP) devices via
802	  the ap bus, cards and queues. Supported Adjunct Processors are
803	  the CryptoExpress Cards (CEX).
804
805	  To compile this driver as a module, choose M here: the
806	  module will be called ap.
807
808	  If unsure, say Y (default).
809
810config AP_DEBUG
811	def_bool n
812	prompt "Enable debug features for Adjunct Processor (ap) devices"
813	depends on AP
814	help
815	  Say 'Y' here to enable some additional debug features for Adjunct
816	  Processor (ap) devices.
817
818	  There will be some more sysfs attributes displayed for ap queues.
819
820	  Do not enable on production level kernel build.
821
822	  If unsure, say N.
823
824config VFIO_CCW
825	def_tristate n
826	prompt "Support for VFIO-CCW subchannels"
827	depends on VFIO
828	select VFIO_MDEV
829	help
830	  This driver allows usage of I/O subchannels via VFIO-CCW.
831
832	  To compile this driver as a module, choose M here: the
833	  module will be called vfio_ccw.
834
835config VFIO_AP
836	def_tristate n
837	prompt "VFIO support for AP devices"
838	depends on KVM
839	depends on VFIO
840	depends on AP
841	select VFIO_MDEV
842	help
843	  This driver grants access to Adjunct Processor (AP) devices
844	  via the VFIO mediated device interface.
845
846	  To compile this driver as a module, choose M here: the module
847	  will be called vfio_ap.
848
849endmenu
850
851config CCW
852	def_bool y
853
854config HAVE_PNETID
855	tristate
856	default (SMC || CCWGROUP)
857
858menu "Virtualization"
859
860config PFAULT
861	def_bool y
862	prompt "Pseudo page fault support"
863	help
864	  Select this option, if you want to use PFAULT pseudo page fault
865	  handling under VM. If running native or in LPAR, this option
866	  has no effect. If your VM does not support PFAULT, PAGEEX
867	  pseudo page fault handling will be used.
868	  Note that VM 4.2 supports PFAULT but has a bug in its
869	  implementation that causes some problems.
870	  Everybody who wants to run Linux under VM != VM4.2 should select
871	  this option.
872
873config CMM
874	def_tristate n
875	prompt "Cooperative memory management"
876	help
877	  Select this option, if you want to enable the kernel interface
878	  to reduce the memory size of the system. This is accomplished
879	  by allocating pages of memory and put them "on hold". This only
880	  makes sense for a system running under VM where the unused pages
881	  will be reused by VM for other guest systems. The interface
882	  allows an external monitor to balance memory of many systems.
883	  Everybody who wants to run Linux under VM should select this
884	  option.
885
886config CMM_IUCV
887	def_bool y
888	prompt "IUCV special message interface to cooperative memory management"
889	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
890	help
891	  Select this option to enable the special message interface to
892	  the cooperative memory management.
893
894config APPLDATA_BASE
895	def_bool n
896	prompt "Linux - VM Monitor Stream, base infrastructure"
897	depends on PROC_SYSCTL
898	help
899	  This provides a kernel interface for creating and updating z/VM APPLDATA
900	  monitor records. The monitor records are updated at certain time
901	  intervals, once the timer is started.
902	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
903	  i.e. enables or disables monitoring on the Linux side.
904	  A custom interval value (in seconds) can be written to
905	  /proc/appldata/interval.
906
907	  Defaults are 60 seconds interval and timer off.
908	  The /proc entries can also be read from, showing the current settings.
909
910config APPLDATA_MEM
911	def_tristate m
912	prompt "Monitor memory management statistics"
913	depends on APPLDATA_BASE && VM_EVENT_COUNTERS
914	help
915	  This provides memory management related data to the Linux - VM Monitor
916	  Stream, like paging/swapping rate, memory utilisation, etc.
917	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
918	  APPLDATA monitor record, i.e. enables or disables monitoring this record
919	  on the z/VM side.
920
921	  Default is disabled.
922	  The /proc entry can also be read from, showing the current settings.
923
924	  This can also be compiled as a module, which will be called
925	  appldata_mem.o.
926
927config APPLDATA_OS
928	def_tristate m
929	prompt "Monitor OS statistics"
930	depends on APPLDATA_BASE
931	help
932	  This provides OS related data to the Linux - VM Monitor Stream, like
933	  CPU utilisation, etc.
934	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
935	  APPLDATA monitor record, i.e. enables or disables monitoring this record
936	  on the z/VM side.
937
938	  Default is disabled.
939	  This can also be compiled as a module, which will be called
940	  appldata_os.o.
941
942config APPLDATA_NET_SUM
943	def_tristate m
944	prompt "Monitor overall network statistics"
945	depends on APPLDATA_BASE && NET
946	help
947	  This provides network related data to the Linux - VM Monitor Stream,
948	  currently there is only a total sum of network I/O statistics, no
949	  per-interface data.
950	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
951	  APPLDATA monitor record, i.e. enables or disables monitoring this record
952	  on the z/VM side.
953
954	  Default is disabled.
955	  This can also be compiled as a module, which will be called
956	  appldata_net_sum.o.
957
958config S390_HYPFS
959	def_bool y
960	prompt "s390 hypervisor information"
961	help
962	  This provides several binary files at (debugfs)/s390_hypfs/ to
963	  provide accounting information in an s390 hypervisor environment.
964
965config S390_HYPFS_FS
966	def_bool n
967	prompt "s390 hypervisor file system support"
968	select SYS_HYPERVISOR
969	depends on S390_HYPFS
970	help
971	  This is a virtual file system intended to provide accounting
972	  information in an s390 hypervisor environment. This file system
973	  is deprecated and should not be used.
974
975	  Say N if you are unsure.
976
977source "arch/s390/kvm/Kconfig"
978
979config S390_GUEST
980	def_bool y
981	prompt "s390 support for virtio devices"
982	select TTY
983	select VIRTUALIZATION
984	select VIRTIO
985	help
986	  Enabling this option adds support for virtio based paravirtual device
987	  drivers on s390.
988
989	  Select this option if you want to run the kernel as a guest under
990	  the KVM hypervisor.
991
992endmenu
993
994config S390_MODULES_SANITY_TEST_HELPERS
995	def_bool n
996
997menu "Selftests"
998
999config S390_UNWIND_SELFTEST
1000	def_tristate n
1001	depends on KUNIT
1002	default KUNIT_ALL_TESTS
1003	prompt "Test unwind functions"
1004	help
1005	  This option enables s390 specific stack unwinder testing kernel
1006	  module. This option is not useful for distributions or general
1007	  kernels, but only for kernel developers working on architecture code.
1008
1009	  Say N if you are unsure.
1010
1011config S390_KPROBES_SANITY_TEST
1012	def_tristate n
1013	prompt "Enable s390 specific kprobes tests"
1014	depends on KPROBES
1015	depends on KUNIT
1016	help
1017	  This option enables an s390 specific kprobes test module. This option
1018	  is not useful for distributions or general kernels, but only for kernel
1019	  developers working on architecture code.
1020
1021	  Say N if you are unsure.
1022
1023config S390_MODULES_SANITY_TEST
1024	def_tristate n
1025	depends on KUNIT
1026	default KUNIT_ALL_TESTS
1027	prompt "Enable s390 specific modules tests"
1028	select S390_MODULES_SANITY_TEST_HELPERS
1029	help
1030	  This option enables an s390 specific modules test. This option is
1031	  not useful for distributions or general kernels, but only for
1032	  kernel developers working on architecture code.
1033
1034	  Say N if you are unsure.
1035endmenu
1036