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 GENERIC_HWEIGHT
21	def_bool y
22
23config GENERIC_BUG
24	def_bool y if BUG
25
26config GENERIC_BUG_RELATIVE_POINTERS
27	def_bool y
28
29config GENERIC_LOCKBREAK
30	def_bool y if PREEMPTION
31
32config PGSTE
33	def_bool y if KVM
34
35config AUDIT_ARCH
36	def_bool y
37
38config NO_IOPORT_MAP
39	def_bool y
40
41config PCI_QUIRKS
42	def_bool n
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 S390
53	def_bool y
54	#
55	# Note: keep this list sorted alphabetically
56	#
57	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
58	select ALTERNATE_USER_ADDRESS_SPACE
59	select ARCH_32BIT_USTAT_F_TINODE
60	select ARCH_BINFMT_ELF_STATE
61	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
62	select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM
63	select ARCH_ENABLE_MEMORY_HOTREMOVE
64	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
65	select ARCH_HAS_CURRENT_STACK_POINTER
66	select ARCH_HAS_DEBUG_VM_PGTABLE
67	select ARCH_HAS_DEBUG_WX
68	select ARCH_HAS_DEVMEM_IS_ALLOWED
69	select ARCH_HAS_ELF_RANDOMIZE
70	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
71	select ARCH_HAS_FORTIFY_SOURCE
72	select ARCH_HAS_GCOV_PROFILE_ALL
73	select ARCH_HAS_GIGANTIC_PAGE
74	select ARCH_HAS_KCOV
75	select ARCH_HAS_MEM_ENCRYPT
76	select ARCH_HAS_PTE_SPECIAL
77	select ARCH_HAS_SCALED_CPUTIME
78	select ARCH_HAS_SET_MEMORY
79	select ARCH_HAS_STRICT_KERNEL_RWX
80	select ARCH_HAS_STRICT_MODULE_RWX
81	select ARCH_HAS_SYSCALL_WRAPPER
82	select ARCH_HAS_UBSAN_SANITIZE_ALL
83	select ARCH_HAS_VDSO_DATA
84	select ARCH_HAVE_NMI_SAFE_CMPXCHG
85	select ARCH_INLINE_READ_LOCK
86	select ARCH_INLINE_READ_LOCK_BH
87	select ARCH_INLINE_READ_LOCK_IRQ
88	select ARCH_INLINE_READ_LOCK_IRQSAVE
89	select ARCH_INLINE_READ_TRYLOCK
90	select ARCH_INLINE_READ_UNLOCK
91	select ARCH_INLINE_READ_UNLOCK_BH
92	select ARCH_INLINE_READ_UNLOCK_IRQ
93	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
94	select ARCH_INLINE_SPIN_LOCK
95	select ARCH_INLINE_SPIN_LOCK_BH
96	select ARCH_INLINE_SPIN_LOCK_IRQ
97	select ARCH_INLINE_SPIN_LOCK_IRQSAVE
98	select ARCH_INLINE_SPIN_TRYLOCK
99	select ARCH_INLINE_SPIN_TRYLOCK_BH
100	select ARCH_INLINE_SPIN_UNLOCK
101	select ARCH_INLINE_SPIN_UNLOCK_BH
102	select ARCH_INLINE_SPIN_UNLOCK_IRQ
103	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
104	select ARCH_INLINE_WRITE_LOCK
105	select ARCH_INLINE_WRITE_LOCK_BH
106	select ARCH_INLINE_WRITE_LOCK_IRQ
107	select ARCH_INLINE_WRITE_LOCK_IRQSAVE
108	select ARCH_INLINE_WRITE_TRYLOCK
109	select ARCH_INLINE_WRITE_UNLOCK
110	select ARCH_INLINE_WRITE_UNLOCK_BH
111	select ARCH_INLINE_WRITE_UNLOCK_IRQ
112	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
113	select ARCH_STACKWALK
114	select ARCH_SUPPORTS_ATOMIC_RMW
115	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
116	select ARCH_SUPPORTS_HUGETLBFS
117	select ARCH_SUPPORTS_NUMA_BALANCING
118	select ARCH_USE_BUILTIN_BSWAP
119	select ARCH_USE_CMPXCHG_LOCKREF
120	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
121	select ARCH_WANTS_NO_INSTR
122	select ARCH_WANT_DEFAULT_BPF_JIT
123	select ARCH_WANT_IPC_PARSE_VERSION
124	select BUILDTIME_TABLE_SORT
125	select CLONE_BACKWARDS2
126	select DMA_OPS if PCI
127	select DYNAMIC_FTRACE if FUNCTION_TRACER
128	select GENERIC_ALLOCATOR
129	select GENERIC_CPU_AUTOPROBE
130	select GENERIC_CPU_VULNERABILITIES
131	select GENERIC_ENTRY
132	select GENERIC_GETTIMEOFDAY
133	select GENERIC_PTDUMP
134	select GENERIC_SMP_IDLE_THREAD
135	select GENERIC_TIME_VSYSCALL
136	select GENERIC_VDSO_TIME_NS
137	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
138	select HAVE_ARCH_AUDITSYSCALL
139	select HAVE_ARCH_JUMP_LABEL
140	select HAVE_ARCH_JUMP_LABEL_RELATIVE
141	select HAVE_ARCH_KASAN
142	select HAVE_ARCH_KASAN_VMALLOC
143	select HAVE_ARCH_KCSAN
144	select HAVE_ARCH_KFENCE
145	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
146	select HAVE_ARCH_SECCOMP_FILTER
147	select HAVE_ARCH_SOFT_DIRTY
148	select HAVE_ARCH_TRACEHOOK
149	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
150	select HAVE_ARCH_VMAP_STACK
151	select HAVE_ASM_MODVERSIONS
152	select HAVE_CMPXCHG_DOUBLE
153	select HAVE_CMPXCHG_LOCAL
154	select HAVE_DEBUG_KMEMLEAK
155	select HAVE_DMA_CONTIGUOUS
156	select HAVE_DYNAMIC_FTRACE
157	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
158	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
159	select HAVE_DYNAMIC_FTRACE_WITH_REGS
160	select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES
161	select HAVE_EFFICIENT_UNALIGNED_ACCESS
162	select HAVE_FAST_GUP
163	select HAVE_FENTRY
164	select HAVE_FTRACE_MCOUNT_RECORD
165	select HAVE_FUNCTION_ARG_ACCESS_API
166	select HAVE_FUNCTION_ERROR_INJECTION
167	select HAVE_FUNCTION_GRAPH_TRACER
168	select HAVE_FUNCTION_TRACER
169	select HAVE_GCC_PLUGINS
170	select HAVE_GENERIC_VDSO
171	select HAVE_IOREMAP_PROT if PCI
172	select HAVE_KERNEL_BZIP2
173	select HAVE_KERNEL_GZIP
174	select HAVE_KERNEL_LZ4
175	select HAVE_KERNEL_LZMA
176	select HAVE_KERNEL_LZO
177	select HAVE_KERNEL_UNCOMPRESSED
178	select HAVE_KERNEL_XZ
179	select HAVE_KERNEL_ZSTD
180	select HAVE_KPROBES
181	select HAVE_KPROBES_ON_FTRACE
182	select HAVE_KRETPROBES
183	select HAVE_KVM
184	select HAVE_LIVEPATCH
185	select HAVE_MEMBLOCK_PHYS_MAP
186	select HAVE_MOD_ARCH_SPECIFIC
187	select HAVE_NMI
188	select HAVE_NOP_MCOUNT
189	select HAVE_PCI
190	select HAVE_PERF_EVENTS
191	select HAVE_PERF_REGS
192	select HAVE_PERF_USER_STACK_DUMP
193	select HAVE_REGS_AND_STACK_ACCESS_API
194	select HAVE_RELIABLE_STACKTRACE
195	select HAVE_RSEQ
196	select HAVE_SAMPLE_FTRACE_DIRECT
197	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
198	select HAVE_SOFTIRQ_ON_OWN_STACK
199	select HAVE_SYSCALL_TRACEPOINTS
200	select HAVE_VIRT_CPU_ACCOUNTING
201	select HAVE_VIRT_CPU_ACCOUNTING_IDLE
202	select IOMMU_HELPER		if PCI
203	select IOMMU_SUPPORT		if PCI
204	select MMU_GATHER_NO_GATHER
205	select MMU_GATHER_RCU_TABLE_FREE
206	select MODULES_USE_ELF_RELA
207	select NEED_DMA_MAP_STATE	if PCI
208	select NEED_SG_DMA_LENGTH	if PCI
209	select OLD_SIGACTION
210	select OLD_SIGSUSPEND3
211	select PCI_DOMAINS		if PCI
212	select PCI_MSI			if PCI
213	select PCI_MSI_ARCH_FALLBACKS	if PCI_MSI
214	select SPARSE_IRQ
215	select SWIOTLB
216	select SYSCTL_EXCEPTION_TRACE
217	select THREAD_INFO_IN_TASK
218	select TRACE_IRQFLAGS_SUPPORT
219	select TTY
220	select VIRT_CPU_ACCOUNTING
221	select ZONE_DMA
222	# Note: keep the above list sorted alphabetically
223
224config SCHED_OMIT_FRAME_POINTER
225	def_bool y
226
227config PGTABLE_LEVELS
228	int
229	default 5
230
231source "kernel/livepatch/Kconfig"
232
233menu "Processor type and features"
234
235config HAVE_MARCH_Z10_FEATURES
236	def_bool n
237
238config HAVE_MARCH_Z196_FEATURES
239	def_bool n
240	select HAVE_MARCH_Z10_FEATURES
241
242config HAVE_MARCH_ZEC12_FEATURES
243	def_bool n
244	select HAVE_MARCH_Z196_FEATURES
245
246config HAVE_MARCH_Z13_FEATURES
247	def_bool n
248	select HAVE_MARCH_ZEC12_FEATURES
249
250config HAVE_MARCH_Z14_FEATURES
251	def_bool n
252	select HAVE_MARCH_Z13_FEATURES
253
254config HAVE_MARCH_Z15_FEATURES
255	def_bool n
256	select HAVE_MARCH_Z14_FEATURES
257
258config HAVE_MARCH_Z16_FEATURES
259	def_bool n
260	select HAVE_MARCH_Z15_FEATURES
261
262choice
263	prompt "Processor type"
264	default MARCH_Z196
265
266config MARCH_Z10
267	bool "IBM System z10"
268	select HAVE_MARCH_Z10_FEATURES
269	depends on $(cc-option,-march=z10)
270	help
271	  Select this to enable optimizations for IBM System z10 (2097 and 2098
272	  series). This is the oldest machine generation currently supported.
273
274config MARCH_Z196
275	bool "IBM zEnterprise 114 and 196"
276	select HAVE_MARCH_Z196_FEATURES
277	depends on $(cc-option,-march=z196)
278	help
279	  Select this to enable optimizations for IBM zEnterprise 114 and 196
280	  (2818 and 2817 series). The kernel will be slightly faster but will
281	  not work on older machines.
282
283config MARCH_ZEC12
284	bool "IBM zBC12 and zEC12"
285	select HAVE_MARCH_ZEC12_FEATURES
286	depends on $(cc-option,-march=zEC12)
287	help
288	  Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
289	  2827 series). The kernel will be slightly faster but will not work on
290	  older machines.
291
292config MARCH_Z13
293	bool "IBM z13s and z13"
294	select HAVE_MARCH_Z13_FEATURES
295	depends on $(cc-option,-march=z13)
296	help
297	  Select this to enable optimizations for IBM z13s and z13 (2965 and
298	  2964 series). The kernel will be slightly faster but will not work on
299	  older machines.
300
301config MARCH_Z14
302	bool "IBM z14 ZR1 and z14"
303	select HAVE_MARCH_Z14_FEATURES
304	depends on $(cc-option,-march=z14)
305	help
306	  Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
307	  and 3906 series). The kernel will be slightly faster but will not
308	  work on older machines.
309
310config MARCH_Z15
311	bool "IBM z15"
312	select HAVE_MARCH_Z15_FEATURES
313	depends on $(cc-option,-march=z15)
314	help
315	  Select this to enable optimizations for IBM z15 (8562
316	  and 8561 series). The kernel will be slightly faster but will not
317	  work on older machines.
318
319config MARCH_Z16
320	bool "IBM z16"
321	select HAVE_MARCH_Z16_FEATURES
322	depends on $(cc-option,-march=z16)
323	help
324	  Select this to enable optimizations for IBM z16 (3931 and
325	  3932 series).
326
327endchoice
328
329config MARCH_Z10_TUNE
330	def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
331
332config MARCH_Z196_TUNE
333	def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
334
335config MARCH_ZEC12_TUNE
336	def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
337
338config MARCH_Z13_TUNE
339	def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
340
341config MARCH_Z14_TUNE
342	def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
343
344config MARCH_Z15_TUNE
345	def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
346
347config MARCH_Z16_TUNE
348	def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT
349
350choice
351	prompt "Tune code generation"
352	default TUNE_DEFAULT
353	help
354	  Cause the compiler to tune (-mtune) the generated code for a machine.
355	  This will make the code run faster on the selected machine but
356	  somewhat slower on other machines.
357	  This option only changes how the compiler emits instructions, not the
358	  selection of instructions itself, so the resulting kernel will run on
359	  all other machines.
360
361config TUNE_DEFAULT
362	bool "Default"
363	help
364	  Tune the generated code for the target processor for which the kernel
365	  will be compiled.
366
367config TUNE_Z10
368	bool "IBM System z10"
369
370config TUNE_Z196
371	bool "IBM zEnterprise 114 and 196"
372	depends on $(cc-option,-mtune=z196)
373
374config TUNE_ZEC12
375	bool "IBM zBC12 and zEC12"
376	depends on $(cc-option,-mtune=zEC12)
377
378config TUNE_Z13
379	bool "IBM z13s and z13"
380	depends on $(cc-option,-mtune=z13)
381
382config TUNE_Z14
383	bool "IBM z14 ZR1 and z14"
384	depends on $(cc-option,-mtune=z14)
385
386config TUNE_Z15
387	bool "IBM z15"
388	depends on $(cc-option,-mtune=z15)
389
390config TUNE_Z16
391	bool "IBM z16"
392	depends on $(cc-option,-mtune=z16)
393
394endchoice
395
396config 64BIT
397	def_bool y
398
399config COMMAND_LINE_SIZE
400	int "Maximum size of kernel command line"
401	default 4096
402	range 896 1048576
403	help
404	  This allows you to specify the maximum length of the kernel command
405	  line.
406
407config COMPAT
408	def_bool y
409	prompt "Kernel support for 31 bit emulation"
410	select ARCH_WANT_OLD_COMPAT_IPC
411	select COMPAT_OLD_SIGACTION
412	select HAVE_UID16
413	depends on MULTIUSER
414	depends on !CC_IS_CLANG
415	help
416	  Select this option if you want to enable your system kernel to
417	  handle system-calls from ELF binaries for 31 bit ESA.  This option
418	  (and some other stuff like libraries and such) is needed for
419	  executing 31 bit applications.  It is safe to say "Y".
420
421config SYSVIPC_COMPAT
422	def_bool y if COMPAT && SYSVIPC
423
424config SMP
425	def_bool y
426
427config NR_CPUS
428	int "Maximum number of CPUs (2-512)"
429	range 2 512
430	default "64"
431	help
432	  This allows you to specify the maximum number of CPUs which this
433	  kernel will support. The maximum supported value is 512 and the
434	  minimum value which makes sense is 2.
435
436	  This is purely to save memory - each supported CPU adds
437	  approximately sixteen kilobytes to the kernel image.
438
439config HOTPLUG_CPU
440	def_bool y
441
442config NUMA
443	bool "NUMA support"
444	depends on SCHED_TOPOLOGY
445	default n
446	help
447	  Enable NUMA support
448
449	  This option adds NUMA support to the kernel.
450
451config NODES_SHIFT
452	int
453	depends on NUMA
454	default "1"
455
456config SCHED_SMT
457	def_bool n
458
459config SCHED_MC
460	def_bool n
461
462config SCHED_BOOK
463	def_bool n
464
465config SCHED_DRAWER
466	def_bool n
467
468config SCHED_TOPOLOGY
469	def_bool y
470	prompt "Topology scheduler support"
471	select SCHED_SMT
472	select SCHED_MC
473	select SCHED_BOOK
474	select SCHED_DRAWER
475	help
476	  Topology scheduler support improves the CPU scheduler's decision
477	  making when dealing with machines that have multi-threading,
478	  multiple cores or multiple books.
479
480source "kernel/Kconfig.hz"
481
482config KEXEC
483	def_bool y
484	select KEXEC_CORE
485
486config KEXEC_FILE
487	bool "kexec file based system call"
488	select KEXEC_CORE
489	select BUILD_BIN2C
490	depends on CRYPTO
491	depends on CRYPTO_SHA256
492	depends on CRYPTO_SHA256_S390
493	help
494	  Enable the kexec file based system call. In contrast to the normal
495	  kexec system call this system call takes file descriptors for the
496	  kernel and initramfs as arguments.
497
498config ARCH_HAS_KEXEC_PURGATORY
499	def_bool y
500	depends on KEXEC_FILE
501
502config KEXEC_SIG
503	bool "Verify kernel signature during kexec_file_load() syscall"
504	depends on KEXEC_FILE && MODULE_SIG_FORMAT
505	help
506	  This option makes kernel signature verification mandatory for
507	  the kexec_file_load() syscall.
508
509	  In addition to that option, you need to enable signature
510	  verification for the corresponding kernel image type being
511	  loaded in order for this to work.
512
513config ARCH_RANDOM
514	def_bool y
515	prompt "s390 architectural random number generation API"
516	help
517	  Enable the s390 architectural random number generation API
518	  to provide random data for all consumers within the Linux
519	  kernel.
520
521	  When enabled the arch_random_* functions declared in linux/random.h
522	  are implemented. The implementation is based on the s390 CPACF
523	  instruction subfunction TRNG which provides a real true random
524	  number generator.
525
526	  If unsure, say Y.
527
528config KERNEL_NOBP
529	def_bool n
530	prompt "Enable modified branch prediction for the kernel by default"
531	help
532	  If this option is selected the kernel will switch to a modified
533	  branch prediction mode if the firmware interface is available.
534	  The modified branch prediction mode improves the behaviour in
535	  regard to speculative execution.
536
537	  With the option enabled the kernel parameter "nobp=0" or "nospec"
538	  can be used to run the kernel in the normal branch prediction mode.
539
540	  With the option disabled the modified branch prediction mode is
541	  enabled with the "nobp=1" kernel parameter.
542
543	  If unsure, say N.
544
545config EXPOLINE
546	def_bool n
547	depends on $(cc-option,-mindirect-branch=thunk)
548	prompt "Avoid speculative indirect branches in the kernel"
549	help
550	  Compile the kernel with the expoline compiler options to guard
551	  against kernel-to-user data leaks by avoiding speculative indirect
552	  branches.
553	  Requires a compiler with -mindirect-branch=thunk support for full
554	  protection. The kernel may run slower.
555
556	  If unsure, say N.
557
558config EXPOLINE_EXTERN
559	def_bool n
560	depends on EXPOLINE
561	depends on CC_IS_GCC && GCC_VERSION >= 110200
562	depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))
563	prompt "Generate expolines as extern functions."
564	help
565	  This option is required for some tooling like kpatch. The kernel is
566	  compiled with -mindirect-branch=thunk-extern and requires a newer
567	  compiler.
568
569	  If unsure, say N.
570
571choice
572	prompt "Expoline default"
573	depends on EXPOLINE
574	default EXPOLINE_FULL
575
576config EXPOLINE_OFF
577	bool "spectre_v2=off"
578
579config EXPOLINE_AUTO
580	bool "spectre_v2=auto"
581
582config EXPOLINE_FULL
583	bool "spectre_v2=on"
584
585endchoice
586
587config RELOCATABLE
588	bool "Build a relocatable kernel"
589	select MODULE_REL_CRCS if MODVERSIONS
590	default y
591	help
592	  This builds a kernel image that retains relocation information
593	  so it can be loaded at an arbitrary address.
594	  The kernel is linked as a position-independent executable (PIE)
595	  and contains dynamic relocations which are processed early in the
596	  bootup process.
597	  The relocations make the kernel image about 15% larger (compressed
598	  10%), but are discarded at runtime.
599
600config RANDOMIZE_BASE
601	bool "Randomize the address of the kernel image (KASLR)"
602	depends on RELOCATABLE
603	default y
604	help
605	  In support of Kernel Address Space Layout Randomization (KASLR),
606	  this randomizes the address at which the kernel image is loaded,
607	  as a security feature that deters exploit attempts relying on
608	  knowledge of the location of kernel internals.
609
610endmenu
611
612menu "Memory setup"
613
614config ARCH_SPARSEMEM_ENABLE
615	def_bool y
616	select SPARSEMEM_VMEMMAP_ENABLE
617	select SPARSEMEM_VMEMMAP
618
619config ARCH_SPARSEMEM_DEFAULT
620	def_bool y
621
622config MAX_PHYSMEM_BITS
623	int "Maximum size of supported physical memory in bits (42-53)"
624	range 42 53
625	default "46"
626	help
627	  This option specifies the maximum supported size of physical memory
628	  in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
629	  Increasing the number of bits also increases the kernel image size.
630	  By default 46 bits (64TB) are supported.
631
632config CHECK_STACK
633	def_bool y
634	depends on !VMAP_STACK
635	prompt "Detect kernel stack overflow"
636	help
637	  This option enables the compiler option -mstack-guard and
638	  -mstack-size if they are available. If the compiler supports them
639	  it will emit additional code to each function prolog to trigger
640	  an illegal operation if the kernel stack is about to overflow.
641
642	  Say N if you are unsure.
643
644config STACK_GUARD
645	int "Size of the guard area (128-1024)"
646	range 128 1024
647	depends on CHECK_STACK
648	default "256"
649	help
650	  This allows you to specify the size of the guard area at the lower
651	  end of the kernel stack. If the kernel stack points into the guard
652	  area on function entry an illegal operation is triggered. The size
653	  needs to be a power of 2. Please keep in mind that the size of an
654	  interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
655	  The minimum size for the stack guard should be 256 for 31 bit and
656	  512 for 64 bit.
657
658endmenu
659
660menu "I/O subsystem"
661
662config QDIO
663	def_tristate y
664	prompt "QDIO support"
665	help
666	  This driver provides the Queued Direct I/O base support for
667	  IBM System z.
668
669	  To compile this driver as a module, choose M here: the
670	  module will be called qdio.
671
672	  If unsure, say Y.
673
674if PCI
675
676config PCI_NR_FUNCTIONS
677	int "Maximum number of PCI functions (1-4096)"
678	range 1 4096
679	default "512"
680	help
681	  This allows you to specify the maximum number of PCI functions which
682	  this kernel will support.
683
684endif # PCI
685
686config HAS_IOMEM
687	def_bool PCI
688
689config CHSC_SCH
690	def_tristate m
691	prompt "Support for CHSC subchannels"
692	help
693	  This driver allows usage of CHSC subchannels. A CHSC subchannel
694	  is usually present on LPAR only.
695	  The driver creates a device /dev/chsc, which may be used to
696	  obtain I/O configuration information about the machine and
697	  to issue asynchronous chsc commands (DANGEROUS).
698	  You will usually only want to use this interface on a special
699	  LPAR designated for system management.
700
701	  To compile this driver as a module, choose M here: the
702	  module will be called chsc_sch.
703
704	  If unsure, say N.
705
706config SCM_BUS
707	def_bool y
708	prompt "SCM bus driver"
709	help
710	  Bus driver for Storage Class Memory.
711
712config EADM_SCH
713	def_tristate m
714	prompt "Support for EADM subchannels"
715	depends on SCM_BUS
716	help
717	  This driver allows usage of EADM subchannels. EADM subchannels act
718	  as a communication vehicle for SCM increments.
719
720	  To compile this driver as a module, choose M here: the
721	  module will be called eadm_sch.
722
723config VFIO_CCW
724	def_tristate n
725	prompt "Support for VFIO-CCW subchannels"
726	depends on S390_CCW_IOMMU && VFIO_MDEV
727	help
728	  This driver allows usage of I/O subchannels via VFIO-CCW.
729
730	  To compile this driver as a module, choose M here: the
731	  module will be called vfio_ccw.
732
733config VFIO_AP
734	def_tristate n
735	prompt "VFIO support for AP devices"
736	depends on S390_AP_IOMMU && VFIO_MDEV && KVM
737	depends on ZCRYPT
738	help
739		This driver grants access to Adjunct Processor (AP) devices
740		via the VFIO mediated device interface.
741
742		To compile this driver as a module, choose M here: the module
743		will be called vfio_ap.
744
745endmenu
746
747menu "Dump support"
748
749config CRASH_DUMP
750	bool "kernel crash dumps"
751	select KEXEC
752	help
753	  Generate crash dump after being started by kexec.
754	  Crash dump kernels are loaded in the main kernel with kexec-tools
755	  into a specially reserved region and then later executed after
756	  a crash by kdump/kexec.
757	  Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this.
758	  This option also enables s390 zfcpdump.
759	  See also <file:Documentation/s390/zfcpdump.rst>
760
761endmenu
762
763config CCW
764	def_bool y
765
766config HAVE_PNETID
767	tristate
768	default (SMC || CCWGROUP)
769
770menu "Virtualization"
771
772config PROTECTED_VIRTUALIZATION_GUEST
773	def_bool n
774	prompt "Protected virtualization guest support"
775	select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
776	help
777	  Select this option, if you want to be able to run this
778	  kernel as a protected virtualization KVM guest.
779	  Protected virtualization capable machines have a mini hypervisor
780	  located at machine level (an ultravisor). With help of the
781	  Ultravisor, KVM will be able to run "protected" VMs, special
782	  VMs whose memory and management data are unavailable to KVM.
783
784config PFAULT
785	def_bool y
786	prompt "Pseudo page fault support"
787	help
788	  Select this option, if you want to use PFAULT pseudo page fault
789	  handling under VM. If running native or in LPAR, this option
790	  has no effect. If your VM does not support PFAULT, PAGEEX
791	  pseudo page fault handling will be used.
792	  Note that VM 4.2 supports PFAULT but has a bug in its
793	  implementation that causes some problems.
794	  Everybody who wants to run Linux under VM != VM4.2 should select
795	  this option.
796
797config CMM
798	def_tristate n
799	prompt "Cooperative memory management"
800	help
801	  Select this option, if you want to enable the kernel interface
802	  to reduce the memory size of the system. This is accomplished
803	  by allocating pages of memory and put them "on hold". This only
804	  makes sense for a system running under VM where the unused pages
805	  will be reused by VM for other guest systems. The interface
806	  allows an external monitor to balance memory of many systems.
807	  Everybody who wants to run Linux under VM should select this
808	  option.
809
810config CMM_IUCV
811	def_bool y
812	prompt "IUCV special message interface to cooperative memory management"
813	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
814	help
815	  Select this option to enable the special message interface to
816	  the cooperative memory management.
817
818config APPLDATA_BASE
819	def_bool n
820	prompt "Linux - VM Monitor Stream, base infrastructure"
821	depends on PROC_SYSCTL
822	help
823	  This provides a kernel interface for creating and updating z/VM APPLDATA
824	  monitor records. The monitor records are updated at certain time
825	  intervals, once the timer is started.
826	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
827	  i.e. enables or disables monitoring on the Linux side.
828	  A custom interval value (in seconds) can be written to
829	  /proc/appldata/interval.
830
831	  Defaults are 60 seconds interval and timer off.
832	  The /proc entries can also be read from, showing the current settings.
833
834config APPLDATA_MEM
835	def_tristate m
836	prompt "Monitor memory management statistics"
837	depends on APPLDATA_BASE && VM_EVENT_COUNTERS
838	help
839	  This provides memory management related data to the Linux - VM Monitor
840	  Stream, like paging/swapping rate, memory utilisation, etc.
841	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
842	  APPLDATA monitor record, i.e. enables or disables monitoring this record
843	  on the z/VM side.
844
845	  Default is disabled.
846	  The /proc entry can also be read from, showing the current settings.
847
848	  This can also be compiled as a module, which will be called
849	  appldata_mem.o.
850
851config APPLDATA_OS
852	def_tristate m
853	prompt "Monitor OS statistics"
854	depends on APPLDATA_BASE
855	help
856	  This provides OS related data to the Linux - VM Monitor Stream, like
857	  CPU utilisation, etc.
858	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
859	  APPLDATA monitor record, i.e. enables or disables monitoring this record
860	  on the z/VM side.
861
862	  Default is disabled.
863	  This can also be compiled as a module, which will be called
864	  appldata_os.o.
865
866config APPLDATA_NET_SUM
867	def_tristate m
868	prompt "Monitor overall network statistics"
869	depends on APPLDATA_BASE && NET
870	help
871	  This provides network related data to the Linux - VM Monitor Stream,
872	  currently there is only a total sum of network I/O statistics, no
873	  per-interface data.
874	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
875	  APPLDATA monitor record, i.e. enables or disables monitoring this record
876	  on the z/VM side.
877
878	  Default is disabled.
879	  This can also be compiled as a module, which will be called
880	  appldata_net_sum.o.
881
882config S390_HYPFS_FS
883	def_bool y
884	prompt "s390 hypervisor file system support"
885	select SYS_HYPERVISOR
886	help
887	  This is a virtual file system intended to provide accounting
888	  information in an s390 hypervisor environment.
889
890source "arch/s390/kvm/Kconfig"
891
892config S390_GUEST
893	def_bool y
894	prompt "s390 support for virtio devices"
895	select TTY
896	select VIRTUALIZATION
897	select VIRTIO
898	help
899	  Enabling this option adds support for virtio based paravirtual device
900	  drivers on s390.
901
902	  Select this option if you want to run the kernel as a guest under
903	  the KVM hypervisor.
904
905endmenu
906
907config S390_MODULES_SANITY_TEST_HELPERS
908	def_bool n
909
910menu "Selftests"
911
912config S390_UNWIND_SELFTEST
913	def_tristate n
914	depends on KUNIT
915	default KUNIT_ALL_TESTS
916	prompt "Test unwind functions"
917	help
918	  This option enables s390 specific stack unwinder testing kernel
919	  module. This option is not useful for distributions or general
920	  kernels, but only for kernel developers working on architecture code.
921
922	  Say N if you are unsure.
923
924config S390_KPROBES_SANITY_TEST
925	def_tristate n
926	prompt "Enable s390 specific kprobes tests"
927	depends on KPROBES
928	depends on KUNIT
929	help
930	  This option enables an s390 specific kprobes test module. This option
931	  is not useful for distributions or general kernels, but only for kernel
932	  developers working on architecture code.
933
934	  Say N if you are unsure.
935
936config S390_MODULES_SANITY_TEST
937	def_tristate n
938	depends on KUNIT
939	default KUNIT_ALL_TESTS
940	prompt "Enable s390 specific modules tests"
941	select S390_MODULES_SANITY_TEST_HELPERS
942	help
943	  This option enables an s390 specific modules test. This option is
944	  not useful for distributions or general kernels, but only for
945	  kernel developers working on architecture code.
946
947	  Say N if you are unsure.
948endmenu
949