xref: /openbmc/linux/arch/s390/Kconfig (revision dff03381)
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 GCC12_NO_ARRAY_BOUNDS
129	select GENERIC_ALLOCATOR
130	select GENERIC_CPU_AUTOPROBE
131	select GENERIC_CPU_VULNERABILITIES
132	select GENERIC_ENTRY
133	select GENERIC_GETTIMEOFDAY
134	select GENERIC_PTDUMP
135	select GENERIC_SMP_IDLE_THREAD
136	select GENERIC_TIME_VSYSCALL
137	select GENERIC_VDSO_TIME_NS
138	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
139	select HAVE_ARCH_AUDITSYSCALL
140	select HAVE_ARCH_JUMP_LABEL
141	select HAVE_ARCH_JUMP_LABEL_RELATIVE
142	select HAVE_ARCH_KASAN
143	select HAVE_ARCH_KASAN_VMALLOC
144	select HAVE_ARCH_KCSAN
145	select HAVE_ARCH_KFENCE
146	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
147	select HAVE_ARCH_SECCOMP_FILTER
148	select HAVE_ARCH_SOFT_DIRTY
149	select HAVE_ARCH_TRACEHOOK
150	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
151	select HAVE_ARCH_VMAP_STACK
152	select HAVE_ASM_MODVERSIONS
153	select HAVE_CMPXCHG_DOUBLE
154	select HAVE_CMPXCHG_LOCAL
155	select HAVE_DEBUG_KMEMLEAK
156	select HAVE_DMA_CONTIGUOUS
157	select HAVE_DYNAMIC_FTRACE
158	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
159	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
160	select HAVE_DYNAMIC_FTRACE_WITH_REGS
161	select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES
162	select HAVE_EFFICIENT_UNALIGNED_ACCESS
163	select HAVE_FAST_GUP
164	select HAVE_FENTRY
165	select HAVE_FTRACE_MCOUNT_RECORD
166	select HAVE_FUNCTION_ARG_ACCESS_API
167	select HAVE_FUNCTION_ERROR_INJECTION
168	select HAVE_FUNCTION_GRAPH_TRACER
169	select HAVE_FUNCTION_TRACER
170	select HAVE_GCC_PLUGINS
171	select HAVE_GENERIC_VDSO
172	select HAVE_IOREMAP_PROT if PCI
173	select HAVE_KERNEL_BZIP2
174	select HAVE_KERNEL_GZIP
175	select HAVE_KERNEL_LZ4
176	select HAVE_KERNEL_LZMA
177	select HAVE_KERNEL_LZO
178	select HAVE_KERNEL_UNCOMPRESSED
179	select HAVE_KERNEL_XZ
180	select HAVE_KERNEL_ZSTD
181	select HAVE_KPROBES
182	select HAVE_KPROBES_ON_FTRACE
183	select HAVE_KRETPROBES
184	select HAVE_KVM
185	select HAVE_LIVEPATCH
186	select HAVE_MEMBLOCK_PHYS_MAP
187	select HAVE_MOD_ARCH_SPECIFIC
188	select HAVE_NMI
189	select HAVE_NOP_MCOUNT
190	select HAVE_PCI
191	select HAVE_PERF_EVENTS
192	select HAVE_PERF_REGS
193	select HAVE_PERF_USER_STACK_DUMP
194	select HAVE_REGS_AND_STACK_ACCESS_API
195	select HAVE_RELIABLE_STACKTRACE
196	select HAVE_RSEQ
197	select HAVE_SAMPLE_FTRACE_DIRECT
198	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
199	select HAVE_SOFTIRQ_ON_OWN_STACK
200	select HAVE_SYSCALL_TRACEPOINTS
201	select HAVE_VIRT_CPU_ACCOUNTING
202	select HAVE_VIRT_CPU_ACCOUNTING_IDLE
203	select IOMMU_HELPER		if PCI
204	select IOMMU_SUPPORT		if PCI
205	select MMU_GATHER_NO_GATHER
206	select MMU_GATHER_RCU_TABLE_FREE
207	select MMU_GATHER_MERGE_VMAS
208	select MODULES_USE_ELF_RELA
209	select NEED_DMA_MAP_STATE	if PCI
210	select NEED_SG_DMA_LENGTH	if PCI
211	select OLD_SIGACTION
212	select OLD_SIGSUSPEND3
213	select PCI_DOMAINS		if PCI
214	select PCI_MSI			if PCI
215	select PCI_MSI_ARCH_FALLBACKS	if PCI_MSI
216	select SPARSE_IRQ
217	select SWIOTLB
218	select SYSCTL_EXCEPTION_TRACE
219	select THREAD_INFO_IN_TASK
220	select TRACE_IRQFLAGS_SUPPORT
221	select TTY
222	select VIRT_CPU_ACCOUNTING
223	select ZONE_DMA
224	# Note: keep the above list sorted alphabetically
225
226config SCHED_OMIT_FRAME_POINTER
227	def_bool y
228
229config PGTABLE_LEVELS
230	int
231	default 5
232
233source "kernel/livepatch/Kconfig"
234
235menu "Processor type and features"
236
237config HAVE_MARCH_Z10_FEATURES
238	def_bool n
239
240config HAVE_MARCH_Z196_FEATURES
241	def_bool n
242	select HAVE_MARCH_Z10_FEATURES
243
244config HAVE_MARCH_ZEC12_FEATURES
245	def_bool n
246	select HAVE_MARCH_Z196_FEATURES
247
248config HAVE_MARCH_Z13_FEATURES
249	def_bool n
250	select HAVE_MARCH_ZEC12_FEATURES
251
252config HAVE_MARCH_Z14_FEATURES
253	def_bool n
254	select HAVE_MARCH_Z13_FEATURES
255
256config HAVE_MARCH_Z15_FEATURES
257	def_bool n
258	select HAVE_MARCH_Z14_FEATURES
259
260config HAVE_MARCH_Z16_FEATURES
261	def_bool n
262	select HAVE_MARCH_Z15_FEATURES
263
264choice
265	prompt "Processor type"
266	default MARCH_Z196
267
268config MARCH_Z10
269	bool "IBM System z10"
270	select HAVE_MARCH_Z10_FEATURES
271	depends on $(cc-option,-march=z10)
272	help
273	  Select this to enable optimizations for IBM System z10 (2097 and 2098
274	  series). This is the oldest machine generation currently supported.
275
276config MARCH_Z196
277	bool "IBM zEnterprise 114 and 196"
278	select HAVE_MARCH_Z196_FEATURES
279	depends on $(cc-option,-march=z196)
280	help
281	  Select this to enable optimizations for IBM zEnterprise 114 and 196
282	  (2818 and 2817 series). The kernel will be slightly faster but will
283	  not work on older machines.
284
285config MARCH_ZEC12
286	bool "IBM zBC12 and zEC12"
287	select HAVE_MARCH_ZEC12_FEATURES
288	depends on $(cc-option,-march=zEC12)
289	help
290	  Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
291	  2827 series). The kernel will be slightly faster but will not work on
292	  older machines.
293
294config MARCH_Z13
295	bool "IBM z13s and z13"
296	select HAVE_MARCH_Z13_FEATURES
297	depends on $(cc-option,-march=z13)
298	help
299	  Select this to enable optimizations for IBM z13s and z13 (2965 and
300	  2964 series). The kernel will be slightly faster but will not work on
301	  older machines.
302
303config MARCH_Z14
304	bool "IBM z14 ZR1 and z14"
305	select HAVE_MARCH_Z14_FEATURES
306	depends on $(cc-option,-march=z14)
307	help
308	  Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
309	  and 3906 series). The kernel will be slightly faster but will not
310	  work on older machines.
311
312config MARCH_Z15
313	bool "IBM z15"
314	select HAVE_MARCH_Z15_FEATURES
315	depends on $(cc-option,-march=z15)
316	help
317	  Select this to enable optimizations for IBM z15 (8562
318	  and 8561 series). The kernel will be slightly faster but will not
319	  work on older machines.
320
321config MARCH_Z16
322	bool "IBM z16"
323	select HAVE_MARCH_Z16_FEATURES
324	depends on $(cc-option,-march=z16)
325	help
326	  Select this to enable optimizations for IBM z16 (3931 and
327	  3932 series).
328
329endchoice
330
331config MARCH_Z10_TUNE
332	def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
333
334config MARCH_Z196_TUNE
335	def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
336
337config MARCH_ZEC12_TUNE
338	def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
339
340config MARCH_Z13_TUNE
341	def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
342
343config MARCH_Z14_TUNE
344	def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
345
346config MARCH_Z15_TUNE
347	def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
348
349config MARCH_Z16_TUNE
350	def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT
351
352choice
353	prompt "Tune code generation"
354	default TUNE_DEFAULT
355	help
356	  Cause the compiler to tune (-mtune) the generated code for a machine.
357	  This will make the code run faster on the selected machine but
358	  somewhat slower on other machines.
359	  This option only changes how the compiler emits instructions, not the
360	  selection of instructions itself, so the resulting kernel will run on
361	  all other machines.
362
363config TUNE_DEFAULT
364	bool "Default"
365	help
366	  Tune the generated code for the target processor for which the kernel
367	  will be compiled.
368
369config TUNE_Z10
370	bool "IBM System z10"
371
372config TUNE_Z196
373	bool "IBM zEnterprise 114 and 196"
374	depends on $(cc-option,-mtune=z196)
375
376config TUNE_ZEC12
377	bool "IBM zBC12 and zEC12"
378	depends on $(cc-option,-mtune=zEC12)
379
380config TUNE_Z13
381	bool "IBM z13s and z13"
382	depends on $(cc-option,-mtune=z13)
383
384config TUNE_Z14
385	bool "IBM z14 ZR1 and z14"
386	depends on $(cc-option,-mtune=z14)
387
388config TUNE_Z15
389	bool "IBM z15"
390	depends on $(cc-option,-mtune=z15)
391
392config TUNE_Z16
393	bool "IBM z16"
394	depends on $(cc-option,-mtune=z16)
395
396endchoice
397
398config 64BIT
399	def_bool y
400
401config COMMAND_LINE_SIZE
402	int "Maximum size of kernel command line"
403	default 4096
404	range 896 1048576
405	help
406	  This allows you to specify the maximum length of the kernel command
407	  line.
408
409config COMPAT
410	def_bool y
411	prompt "Kernel support for 31 bit emulation"
412	select ARCH_WANT_OLD_COMPAT_IPC
413	select COMPAT_OLD_SIGACTION
414	select HAVE_UID16
415	depends on MULTIUSER
416	depends on !CC_IS_CLANG
417	help
418	  Select this option if you want to enable your system kernel to
419	  handle system-calls from ELF binaries for 31 bit ESA.  This option
420	  (and some other stuff like libraries and such) is needed for
421	  executing 31 bit applications.  It is safe to say "Y".
422
423config SMP
424	def_bool y
425
426config NR_CPUS
427	int "Maximum number of CPUs (2-512)"
428	range 2 512
429	default "64"
430	help
431	  This allows you to specify the maximum number of CPUs which this
432	  kernel will support. The maximum supported value is 512 and the
433	  minimum value which makes sense is 2.
434
435	  This is purely to save memory - each supported CPU adds
436	  approximately sixteen kilobytes to the kernel image.
437
438config HOTPLUG_CPU
439	def_bool y
440
441config NUMA
442	bool "NUMA support"
443	depends on SCHED_TOPOLOGY
444	default n
445	help
446	  Enable NUMA support
447
448	  This option adds NUMA support to the kernel.
449
450config NODES_SHIFT
451	int
452	depends on NUMA
453	default "1"
454
455config SCHED_SMT
456	def_bool n
457
458config SCHED_MC
459	def_bool n
460
461config SCHED_BOOK
462	def_bool n
463
464config SCHED_DRAWER
465	def_bool n
466
467config SCHED_TOPOLOGY
468	def_bool y
469	prompt "Topology scheduler support"
470	select SCHED_SMT
471	select SCHED_MC
472	select SCHED_BOOK
473	select SCHED_DRAWER
474	help
475	  Topology scheduler support improves the CPU scheduler's decision
476	  making when dealing with machines that have multi-threading,
477	  multiple cores or multiple books.
478
479source "kernel/Kconfig.hz"
480
481config KEXEC
482	def_bool y
483	select KEXEC_CORE
484
485config KEXEC_FILE
486	bool "kexec file based system call"
487	select KEXEC_CORE
488	depends on CRYPTO
489	depends on CRYPTO_SHA256
490	depends on CRYPTO_SHA256_S390
491	help
492	  Enable the kexec file based system call. In contrast to the normal
493	  kexec system call this system call takes file descriptors for the
494	  kernel and initramfs as arguments.
495
496config ARCH_HAS_KEXEC_PURGATORY
497	def_bool y
498	depends on KEXEC_FILE
499
500config KEXEC_SIG
501	bool "Verify kernel signature during kexec_file_load() syscall"
502	depends on KEXEC_FILE && MODULE_SIG_FORMAT
503	help
504	  This option makes kernel signature verification mandatory for
505	  the kexec_file_load() syscall.
506
507	  In addition to that option, you need to enable signature
508	  verification for the corresponding kernel image type being
509	  loaded in order for this to work.
510
511config KERNEL_NOBP
512	def_bool n
513	prompt "Enable modified branch prediction for the kernel by default"
514	help
515	  If this option is selected the kernel will switch to a modified
516	  branch prediction mode if the firmware interface is available.
517	  The modified branch prediction mode improves the behaviour in
518	  regard to speculative execution.
519
520	  With the option enabled the kernel parameter "nobp=0" or "nospec"
521	  can be used to run the kernel in the normal branch prediction mode.
522
523	  With the option disabled the modified branch prediction mode is
524	  enabled with the "nobp=1" kernel parameter.
525
526	  If unsure, say N.
527
528config EXPOLINE
529	def_bool n
530	depends on $(cc-option,-mindirect-branch=thunk)
531	prompt "Avoid speculative indirect branches in the kernel"
532	help
533	  Compile the kernel with the expoline compiler options to guard
534	  against kernel-to-user data leaks by avoiding speculative indirect
535	  branches.
536	  Requires a compiler with -mindirect-branch=thunk support for full
537	  protection. The kernel may run slower.
538
539	  If unsure, say N.
540
541config EXPOLINE_EXTERN
542	def_bool n
543	depends on EXPOLINE
544	depends on CC_IS_GCC && GCC_VERSION >= 110200
545	depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))
546	prompt "Generate expolines as extern functions."
547	help
548	  This option is required for some tooling like kpatch. The kernel is
549	  compiled with -mindirect-branch=thunk-extern and requires a newer
550	  compiler.
551
552	  If unsure, say N.
553
554choice
555	prompt "Expoline default"
556	depends on EXPOLINE
557	default EXPOLINE_FULL
558
559config EXPOLINE_OFF
560	bool "spectre_v2=off"
561
562config EXPOLINE_AUTO
563	bool "spectre_v2=auto"
564
565config EXPOLINE_FULL
566	bool "spectre_v2=on"
567
568endchoice
569
570config RELOCATABLE
571	bool "Build a relocatable kernel"
572	default y
573	help
574	  This builds a kernel image that retains relocation information
575	  so it can be loaded at an arbitrary address.
576	  The kernel is linked as a position-independent executable (PIE)
577	  and contains dynamic relocations which are processed early in the
578	  bootup process.
579	  The relocations make the kernel image about 15% larger (compressed
580	  10%), but are discarded at runtime.
581
582config RANDOMIZE_BASE
583	bool "Randomize the address of the kernel image (KASLR)"
584	depends on RELOCATABLE
585	default y
586	help
587	  In support of Kernel Address Space Layout Randomization (KASLR),
588	  this randomizes the address at which the kernel image is loaded,
589	  as a security feature that deters exploit attempts relying on
590	  knowledge of the location of kernel internals.
591
592endmenu
593
594menu "Memory setup"
595
596config ARCH_SPARSEMEM_ENABLE
597	def_bool y
598	select SPARSEMEM_VMEMMAP_ENABLE
599	select SPARSEMEM_VMEMMAP
600
601config ARCH_SPARSEMEM_DEFAULT
602	def_bool y
603
604config MAX_PHYSMEM_BITS
605	int "Maximum size of supported physical memory in bits (42-53)"
606	range 42 53
607	default "46"
608	help
609	  This option specifies the maximum supported size of physical memory
610	  in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
611	  Increasing the number of bits also increases the kernel image size.
612	  By default 46 bits (64TB) are supported.
613
614config CHECK_STACK
615	def_bool y
616	depends on !VMAP_STACK
617	prompt "Detect kernel stack overflow"
618	help
619	  This option enables the compiler option -mstack-guard and
620	  -mstack-size if they are available. If the compiler supports them
621	  it will emit additional code to each function prolog to trigger
622	  an illegal operation if the kernel stack is about to overflow.
623
624	  Say N if you are unsure.
625
626config STACK_GUARD
627	int "Size of the guard area (128-1024)"
628	range 128 1024
629	depends on CHECK_STACK
630	default "256"
631	help
632	  This allows you to specify the size of the guard area at the lower
633	  end of the kernel stack. If the kernel stack points into the guard
634	  area on function entry an illegal operation is triggered. The size
635	  needs to be a power of 2. Please keep in mind that the size of an
636	  interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
637	  The minimum size for the stack guard should be 256 for 31 bit and
638	  512 for 64 bit.
639
640endmenu
641
642menu "I/O subsystem"
643
644config QDIO
645	def_tristate y
646	prompt "QDIO support"
647	help
648	  This driver provides the Queued Direct I/O base support for
649	  IBM System z.
650
651	  To compile this driver as a module, choose M here: the
652	  module will be called qdio.
653
654	  If unsure, say Y.
655
656if PCI
657
658config PCI_NR_FUNCTIONS
659	int "Maximum number of PCI functions (1-4096)"
660	range 1 4096
661	default "512"
662	help
663	  This allows you to specify the maximum number of PCI functions which
664	  this kernel will support.
665
666endif # PCI
667
668config HAS_IOMEM
669	def_bool PCI
670
671config CHSC_SCH
672	def_tristate m
673	prompt "Support for CHSC subchannels"
674	help
675	  This driver allows usage of CHSC subchannels. A CHSC subchannel
676	  is usually present on LPAR only.
677	  The driver creates a device /dev/chsc, which may be used to
678	  obtain I/O configuration information about the machine and
679	  to issue asynchronous chsc commands (DANGEROUS).
680	  You will usually only want to use this interface on a special
681	  LPAR designated for system management.
682
683	  To compile this driver as a module, choose M here: the
684	  module will be called chsc_sch.
685
686	  If unsure, say N.
687
688config SCM_BUS
689	def_bool y
690	prompt "SCM bus driver"
691	help
692	  Bus driver for Storage Class Memory.
693
694config EADM_SCH
695	def_tristate m
696	prompt "Support for EADM subchannels"
697	depends on SCM_BUS
698	help
699	  This driver allows usage of EADM subchannels. EADM subchannels act
700	  as a communication vehicle for SCM increments.
701
702	  To compile this driver as a module, choose M here: the
703	  module will be called eadm_sch.
704
705config VFIO_CCW
706	def_tristate n
707	prompt "Support for VFIO-CCW subchannels"
708	depends on S390_CCW_IOMMU && VFIO_MDEV
709	help
710	  This driver allows usage of I/O subchannels via VFIO-CCW.
711
712	  To compile this driver as a module, choose M here: the
713	  module will be called vfio_ccw.
714
715config VFIO_AP
716	def_tristate n
717	prompt "VFIO support for AP devices"
718	depends on S390_AP_IOMMU && VFIO_MDEV && KVM
719	depends on ZCRYPT
720	help
721	  This driver grants access to Adjunct Processor (AP) devices
722	  via the VFIO mediated device interface.
723
724	  To compile this driver as a module, choose M here: the module
725	  will be called vfio_ap.
726
727endmenu
728
729menu "Dump support"
730
731config CRASH_DUMP
732	bool "kernel crash dumps"
733	select KEXEC
734	help
735	  Generate crash dump after being started by kexec.
736	  Crash dump kernels are loaded in the main kernel with kexec-tools
737	  into a specially reserved region and then later executed after
738	  a crash by kdump/kexec.
739	  Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this.
740	  This option also enables s390 zfcpdump.
741	  See also <file:Documentation/s390/zfcpdump.rst>
742
743endmenu
744
745config CCW
746	def_bool y
747
748config HAVE_PNETID
749	tristate
750	default (SMC || CCWGROUP)
751
752menu "Virtualization"
753
754config PROTECTED_VIRTUALIZATION_GUEST
755	def_bool n
756	prompt "Protected virtualization guest support"
757	help
758	  Select this option, if you want to be able to run this
759	  kernel as a protected virtualization KVM guest.
760	  Protected virtualization capable machines have a mini hypervisor
761	  located at machine level (an ultravisor). With help of the
762	  Ultravisor, KVM will be able to run "protected" VMs, special
763	  VMs whose memory and management data are unavailable to KVM.
764
765config PFAULT
766	def_bool y
767	prompt "Pseudo page fault support"
768	help
769	  Select this option, if you want to use PFAULT pseudo page fault
770	  handling under VM. If running native or in LPAR, this option
771	  has no effect. If your VM does not support PFAULT, PAGEEX
772	  pseudo page fault handling will be used.
773	  Note that VM 4.2 supports PFAULT but has a bug in its
774	  implementation that causes some problems.
775	  Everybody who wants to run Linux under VM != VM4.2 should select
776	  this option.
777
778config CMM
779	def_tristate n
780	prompt "Cooperative memory management"
781	help
782	  Select this option, if you want to enable the kernel interface
783	  to reduce the memory size of the system. This is accomplished
784	  by allocating pages of memory and put them "on hold". This only
785	  makes sense for a system running under VM where the unused pages
786	  will be reused by VM for other guest systems. The interface
787	  allows an external monitor to balance memory of many systems.
788	  Everybody who wants to run Linux under VM should select this
789	  option.
790
791config CMM_IUCV
792	def_bool y
793	prompt "IUCV special message interface to cooperative memory management"
794	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
795	help
796	  Select this option to enable the special message interface to
797	  the cooperative memory management.
798
799config APPLDATA_BASE
800	def_bool n
801	prompt "Linux - VM Monitor Stream, base infrastructure"
802	depends on PROC_SYSCTL
803	help
804	  This provides a kernel interface for creating and updating z/VM APPLDATA
805	  monitor records. The monitor records are updated at certain time
806	  intervals, once the timer is started.
807	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
808	  i.e. enables or disables monitoring on the Linux side.
809	  A custom interval value (in seconds) can be written to
810	  /proc/appldata/interval.
811
812	  Defaults are 60 seconds interval and timer off.
813	  The /proc entries can also be read from, showing the current settings.
814
815config APPLDATA_MEM
816	def_tristate m
817	prompt "Monitor memory management statistics"
818	depends on APPLDATA_BASE && VM_EVENT_COUNTERS
819	help
820	  This provides memory management related data to the Linux - VM Monitor
821	  Stream, like paging/swapping rate, memory utilisation, etc.
822	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
823	  APPLDATA monitor record, i.e. enables or disables monitoring this record
824	  on the z/VM side.
825
826	  Default is disabled.
827	  The /proc entry can also be read from, showing the current settings.
828
829	  This can also be compiled as a module, which will be called
830	  appldata_mem.o.
831
832config APPLDATA_OS
833	def_tristate m
834	prompt "Monitor OS statistics"
835	depends on APPLDATA_BASE
836	help
837	  This provides OS related data to the Linux - VM Monitor Stream, like
838	  CPU utilisation, etc.
839	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
840	  APPLDATA monitor record, i.e. enables or disables monitoring this record
841	  on the z/VM side.
842
843	  Default is disabled.
844	  This can also be compiled as a module, which will be called
845	  appldata_os.o.
846
847config APPLDATA_NET_SUM
848	def_tristate m
849	prompt "Monitor overall network statistics"
850	depends on APPLDATA_BASE && NET
851	help
852	  This provides network related data to the Linux - VM Monitor Stream,
853	  currently there is only a total sum of network I/O statistics, no
854	  per-interface data.
855	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
856	  APPLDATA monitor record, i.e. enables or disables monitoring this record
857	  on the z/VM side.
858
859	  Default is disabled.
860	  This can also be compiled as a module, which will be called
861	  appldata_net_sum.o.
862
863config S390_HYPFS_FS
864	def_bool y
865	prompt "s390 hypervisor file system support"
866	select SYS_HYPERVISOR
867	help
868	  This is a virtual file system intended to provide accounting
869	  information in an s390 hypervisor environment.
870
871source "arch/s390/kvm/Kconfig"
872
873config S390_GUEST
874	def_bool y
875	prompt "s390 support for virtio devices"
876	select TTY
877	select VIRTUALIZATION
878	select VIRTIO
879	help
880	  Enabling this option adds support for virtio based paravirtual device
881	  drivers on s390.
882
883	  Select this option if you want to run the kernel as a guest under
884	  the KVM hypervisor.
885
886endmenu
887
888config S390_MODULES_SANITY_TEST_HELPERS
889	def_bool n
890
891menu "Selftests"
892
893config S390_UNWIND_SELFTEST
894	def_tristate n
895	depends on KUNIT
896	default KUNIT_ALL_TESTS
897	prompt "Test unwind functions"
898	help
899	  This option enables s390 specific stack unwinder testing kernel
900	  module. This option is not useful for distributions or general
901	  kernels, but only for kernel developers working on architecture code.
902
903	  Say N if you are unsure.
904
905config S390_KPROBES_SANITY_TEST
906	def_tristate n
907	prompt "Enable s390 specific kprobes tests"
908	depends on KPROBES
909	depends on KUNIT
910	help
911	  This option enables an s390 specific kprobes test module. This option
912	  is not useful for distributions or general kernels, but only for kernel
913	  developers working on architecture code.
914
915	  Say N if you are unsure.
916
917config S390_MODULES_SANITY_TEST
918	def_tristate n
919	depends on KUNIT
920	default KUNIT_ALL_TESTS
921	prompt "Enable s390 specific modules tests"
922	select S390_MODULES_SANITY_TEST_HELPERS
923	help
924	  This option enables an s390 specific modules test. This option is
925	  not useful for distributions or general kernels, but only for
926	  kernel developers working on architecture code.
927
928	  Say N if you are unsure.
929endmenu
930