xref: /linux/arch/s390/Kconfig (revision ff10fca5ceacf7bc59636f5ab808e775d1717167)
1#
2# For a description of the syntax of this configuration file,
3# see Documentation/kbuild/kconfig-language.txt.
4#
5
6config SCHED_MC
7	def_bool y
8	depends on SMP
9
10config MMU
11	def_bool y
12
13config ZONE_DMA
14	def_bool y
15	depends on 64BIT
16
17config LOCKDEP_SUPPORT
18	def_bool y
19
20config STACKTRACE_SUPPORT
21	def_bool y
22
23config HAVE_LATENCYTOP_SUPPORT
24	def_bool y
25
26config RWSEM_GENERIC_SPINLOCK
27	bool
28
29config RWSEM_XCHGADD_ALGORITHM
30	def_bool y
31
32config ARCH_HAS_ILOG2_U32
33	bool
34	default n
35
36config ARCH_HAS_ILOG2_U64
37	bool
38	default n
39
40config GENERIC_HWEIGHT
41	def_bool y
42
43config GENERIC_TIME_VSYSCALL
44	def_bool y
45
46config GENERIC_CLOCKEVENTS
47	def_bool y
48
49config GENERIC_BUG
50	bool
51	depends on BUG
52	default y
53
54config GENERIC_BUG_RELATIVE_POINTERS
55	def_bool y
56
57config NO_IOMEM
58	def_bool y
59
60config NO_DMA
61	def_bool y
62
63config GENERIC_LOCKBREAK
64	bool
65	default y
66	depends on SMP && PREEMPT
67
68config PGSTE
69	bool
70	default y if KVM
71
72config VIRT_CPU_ACCOUNTING
73	def_bool y
74
75config ARCH_SUPPORTS_DEBUG_PAGEALLOC
76	def_bool y
77
78mainmenu "Linux Kernel Configuration"
79
80config S390
81	def_bool y
82	select USE_GENERIC_SMP_HELPERS if SMP
83	select HAVE_SYSCALL_WRAPPERS
84	select HAVE_FUNCTION_TRACER
85	select HAVE_FUNCTION_TRACE_MCOUNT_TEST
86	select HAVE_FTRACE_MCOUNT_RECORD
87	select HAVE_SYSCALL_TRACEPOINTS
88	select HAVE_DYNAMIC_FTRACE
89	select HAVE_FUNCTION_GRAPH_TRACER
90	select HAVE_REGS_AND_STACK_ACCESS_API
91	select HAVE_DEFAULT_NO_SPIN_MUTEXES
92	select HAVE_OPROFILE
93	select HAVE_KPROBES
94	select HAVE_KRETPROBES
95	select HAVE_KVM if 64BIT
96	select HAVE_ARCH_TRACEHOOK
97	select INIT_ALL_POSSIBLE
98	select HAVE_IRQ_WORK
99	select HAVE_PERF_EVENTS
100	select HAVE_KERNEL_GZIP
101	select HAVE_KERNEL_BZIP2
102	select HAVE_KERNEL_LZMA
103	select HAVE_KERNEL_LZO
104	select ARCH_INLINE_SPIN_TRYLOCK
105	select ARCH_INLINE_SPIN_TRYLOCK_BH
106	select ARCH_INLINE_SPIN_LOCK
107	select ARCH_INLINE_SPIN_LOCK_BH
108	select ARCH_INLINE_SPIN_LOCK_IRQ
109	select ARCH_INLINE_SPIN_LOCK_IRQSAVE
110	select ARCH_INLINE_SPIN_UNLOCK
111	select ARCH_INLINE_SPIN_UNLOCK_BH
112	select ARCH_INLINE_SPIN_UNLOCK_IRQ
113	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
114	select ARCH_INLINE_READ_TRYLOCK
115	select ARCH_INLINE_READ_LOCK
116	select ARCH_INLINE_READ_LOCK_BH
117	select ARCH_INLINE_READ_LOCK_IRQ
118	select ARCH_INLINE_READ_LOCK_IRQSAVE
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_WRITE_TRYLOCK
124	select ARCH_INLINE_WRITE_LOCK
125	select ARCH_INLINE_WRITE_LOCK_BH
126	select ARCH_INLINE_WRITE_LOCK_IRQ
127	select ARCH_INLINE_WRITE_LOCK_IRQSAVE
128	select ARCH_INLINE_WRITE_UNLOCK
129	select ARCH_INLINE_WRITE_UNLOCK_BH
130	select ARCH_INLINE_WRITE_UNLOCK_IRQ
131	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
132
133config SCHED_OMIT_FRAME_POINTER
134	bool
135	default y
136
137source "init/Kconfig"
138
139source "kernel/Kconfig.freezer"
140
141menu "Base setup"
142
143comment "Processor type and features"
144
145source "kernel/time/Kconfig"
146
147config 64BIT
148	bool "64 bit kernel"
149	help
150	  Select this option if you have a 64 bit IBM zSeries machine
151	  and want to use the 64 bit addressing mode.
152
153config 32BIT
154	bool
155	default y if !64BIT
156
157config KTIME_SCALAR
158	def_bool 32BIT
159
160config SMP
161	bool "Symmetric multi-processing support"
162	---help---
163	  This enables support for systems with more than one CPU. If you have
164	  a system with only one CPU, like most personal computers, say N. If
165	  you have a system with more than one CPU, say Y.
166
167	  If you say N here, the kernel will run on single and multiprocessor
168	  machines, but will use only one CPU of a multiprocessor machine. If
169	  you say Y here, the kernel will run on many, but not all,
170	  singleprocessor machines. On a singleprocessor machine, the kernel
171	  will run faster if you say N here.
172
173	  See also the SMP-HOWTO available at
174	  <http://www.tldp.org/docs.html#howto>.
175
176	  Even if you don't know what to do here, say Y.
177
178config NR_CPUS
179	int "Maximum number of CPUs (2-64)"
180	range 2 64
181	depends on SMP
182	default "32" if !64BIT
183	default "64" if 64BIT
184	help
185	  This allows you to specify the maximum number of CPUs which this
186	  kernel will support.  The maximum supported value is 64 and the
187	  minimum value which makes sense is 2.
188
189	  This is purely to save memory - each supported CPU adds
190	  approximately sixteen kilobytes to the kernel image.
191
192config HOTPLUG_CPU
193	bool "Support for hot-pluggable CPUs"
194	depends on SMP
195	select HOTPLUG
196	default n
197	help
198	  Say Y here to be able to turn CPUs off and on. CPUs
199	  can be controlled through /sys/devices/system/cpu/cpu#.
200	  Say N if you want to disable CPU hotplug.
201
202config SCHED_BOOK
203	bool "Book scheduler support"
204	depends on SMP
205	help
206	  Book scheduler support improves the CPU scheduler's decision making
207	  when dealing with machines that have several books.
208
209config MATHEMU
210	bool "IEEE FPU emulation"
211	depends on MARCH_G5
212	help
213	  This option is required for IEEE compliant floating point arithmetic
214	  on older S/390 machines. Say Y unless you know your machine doesn't
215	  need this.
216
217config COMPAT
218	bool "Kernel support for 31 bit emulation"
219	depends on 64BIT
220	select COMPAT_BINFMT_ELF
221	help
222	  Select this option if you want to enable your system kernel to
223	  handle system-calls from ELF binaries for 31 bit ESA.  This option
224	  (and some other stuff like libraries and such) is needed for
225	  executing 31 bit applications.  It is safe to say "Y".
226
227config SYSVIPC_COMPAT
228	bool
229	depends on COMPAT && SYSVIPC
230	default y
231
232config AUDIT_ARCH
233	bool
234	default y
235
236config S390_EXEC_PROTECT
237	bool "Data execute protection"
238	help
239	  This option allows to enable a buffer overflow protection for user
240	  space programs and it also selects the addressing mode option above.
241	  The kernel parameter noexec=on will enable this feature and also
242	  switch the addressing modes, default is disabled. Enabling this (via
243	  kernel parameter) on machines earlier than IBM System z9-109 EC/BC
244	  will reduce system performance.
245
246comment "Code generation options"
247
248choice
249	prompt "Processor type"
250	default MARCH_G5
251
252config MARCH_G5
253	bool "S/390 model G5 and G6"
254	depends on !64BIT
255	help
256	  Select this to build a 31 bit kernel that works
257	  on all S/390 and zSeries machines.
258
259config MARCH_Z900
260	bool "IBM eServer zSeries model z800 and z900"
261	help
262	  Select this to optimize for zSeries machines. This
263	  will enable some optimizations that are not available
264	  on older 31 bit only CPUs.
265
266config MARCH_Z990
267	bool "IBM eServer zSeries model z890 and z990"
268	help
269	  Select this enable optimizations for model z890/z990.
270	  This will be slightly faster but does not work on
271	  older machines such as the z900.
272
273config MARCH_Z9_109
274	bool "IBM System z9"
275	help
276	  Select this to enable optimizations for IBM System z9-109, IBM
277	  System z9 Enterprise Class (z9 EC), and IBM System z9 Business
278	  Class (z9 BC). The kernel will be slightly faster but will not
279	  work on older machines such as the z990, z890, z900, and z800.
280
281config MARCH_Z10
282	bool "IBM System z10"
283	help
284	  Select this to enable optimizations for IBM System z10. The
285	  kernel will be slightly faster but will not work on older
286	  machines such as the z990, z890, z900, z800, z9-109, z9-ec
287	  and z9-bc.
288
289endchoice
290
291config PACK_STACK
292	bool "Pack kernel stack"
293	help
294	  This option enables the compiler option -mkernel-backchain if it
295	  is available. If the option is available the compiler supports
296	  the new stack layout which dramatically reduces the minimum stack
297	  frame size. With an old compiler a non-leaf function needs a
298	  minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
299	  -mkernel-backchain the minimum size drops to 16 byte on 31 bit
300	  and 24 byte on 64 bit.
301
302	  Say Y if you are unsure.
303
304config SMALL_STACK
305	bool "Use 8kb for kernel stack instead of 16kb"
306	depends on PACK_STACK && 64BIT && !LOCKDEP
307	help
308	  If you say Y here and the compiler supports the -mkernel-backchain
309	  option the kernel will use a smaller kernel stack size. The reduced
310	  size is 8kb instead of 16kb. This allows to run more threads on a
311	  system and reduces the pressure on the memory management for higher
312	  order page allocations.
313
314	  Say N if you are unsure.
315
316config CHECK_STACK
317	bool "Detect kernel stack overflow"
318	help
319	  This option enables the compiler option -mstack-guard and
320	  -mstack-size if they are available. If the compiler supports them
321	  it will emit additional code to each function prolog to trigger
322	  an illegal operation if the kernel stack is about to overflow.
323
324	  Say N if you are unsure.
325
326config STACK_GUARD
327	int "Size of the guard area (128-1024)"
328	range 128 1024
329	depends on CHECK_STACK
330	default "256"
331	help
332	  This allows you to specify the size of the guard area at the lower
333	  end of the kernel stack. If the kernel stack points into the guard
334	  area on function entry an illegal operation is triggered. The size
335	  needs to be a power of 2. Please keep in mind that the size of an
336	  interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
337	  The minimum size for the stack guard should be 256 for 31 bit and
338	  512 for 64 bit.
339
340config WARN_STACK
341	bool "Emit compiler warnings for function with broken stack usage"
342	help
343	  This option enables the compiler options -mwarn-framesize and
344	  -mwarn-dynamicstack. If the compiler supports these options it
345	  will generate warnings for function which either use alloca or
346	  create a stack frame bigger than CONFIG_WARN_STACK_SIZE.
347
348	  Say N if you are unsure.
349
350config WARN_STACK_SIZE
351	int "Maximum frame size considered safe (128-2048)"
352	range 128 2048
353	depends on WARN_STACK
354	default "2048"
355	help
356	  This allows you to specify the maximum frame size a function may
357	  have without the compiler complaining about it.
358
359config ARCH_POPULATES_NODE_MAP
360	def_bool y
361
362comment "Kernel preemption"
363
364source "kernel/Kconfig.preempt"
365
366config ARCH_SPARSEMEM_ENABLE
367	def_bool y
368	select SPARSEMEM_VMEMMAP_ENABLE
369	select SPARSEMEM_VMEMMAP
370	select SPARSEMEM_STATIC if !64BIT
371
372config ARCH_SPARSEMEM_DEFAULT
373	def_bool y
374
375config ARCH_SELECT_MEMORY_MODEL
376       def_bool y
377
378config ARCH_ENABLE_MEMORY_HOTPLUG
379	def_bool y
380	depends on SPARSEMEM
381
382config ARCH_ENABLE_MEMORY_HOTREMOVE
383	def_bool y
384
385config ARCH_HIBERNATION_POSSIBLE
386       def_bool y if 64BIT
387
388source "mm/Kconfig"
389
390comment "I/O subsystem configuration"
391
392config QDIO
393	tristate "QDIO support"
394	---help---
395	  This driver provides the Queued Direct I/O base support for
396	  IBM System z.
397
398	  To compile this driver as a module, choose M here: the
399	  module will be called qdio.
400
401	  If unsure, say Y.
402
403config CHSC_SCH
404	tristate "Support for CHSC subchannels"
405	help
406	  This driver allows usage of CHSC subchannels. A CHSC subchannel
407	  is usually present on LPAR only.
408	  The driver creates a device /dev/chsc, which may be used to
409	  obtain I/O configuration information about the machine and
410	  to issue asynchronous chsc commands (DANGEROUS).
411	  You will usually only want to use this interface on a special
412	  LPAR designated for system management.
413
414	  To compile this driver as a module, choose M here: the
415	  module will be called chsc_sch.
416
417	  If unsure, say N.
418
419comment "Misc"
420
421config IPL
422	bool "Builtin IPL record support"
423	help
424	  If you want to use the produced kernel to IPL directly from a
425	  device, you have to merge a bootsector specific to the device
426	  into the first bytes of the kernel. You will have to select the
427	  IPL device.
428
429choice
430	prompt "IPL method generated into head.S"
431	depends on IPL
432	default IPL_VM
433	help
434	  Select "tape" if you want to IPL the image from a Tape.
435
436	  Select "vm_reader" if you are running under VM/ESA and want
437	  to IPL the image from the emulated card reader.
438
439config IPL_TAPE
440	bool "tape"
441
442config IPL_VM
443	bool "vm_reader"
444
445endchoice
446
447source "fs/Kconfig.binfmt"
448
449config FORCE_MAX_ZONEORDER
450	int
451	default "9"
452
453config PFAULT
454	bool "Pseudo page fault support"
455	help
456	  Select this option, if you want to use PFAULT pseudo page fault
457	  handling under VM. If running native or in LPAR, this option
458	  has no effect. If your VM does not support PFAULT, PAGEEX
459	  pseudo page fault handling will be used.
460	  Note that VM 4.2 supports PFAULT but has a bug in its
461	  implementation that causes some problems.
462	  Everybody who wants to run Linux under VM != VM4.2 should select
463	  this option.
464
465config SHARED_KERNEL
466	bool "VM shared kernel support"
467	help
468	  Select this option, if you want to share the text segment of the
469	  Linux kernel between different VM guests. This reduces memory
470	  usage with lots of guests but greatly increases kernel size.
471	  Also if a kernel was IPL'ed from a shared segment the kexec system
472	  call will not work.
473	  You should only select this option if you know what you are
474	  doing and want to exploit this feature.
475
476config CMM
477	tristate "Cooperative memory management"
478	help
479	  Select this option, if you want to enable the kernel interface
480	  to reduce the memory size of the system. This is accomplished
481	  by allocating pages of memory and put them "on hold". This only
482	  makes sense for a system running under VM where the unused pages
483	  will be reused by VM for other guest systems. The interface
484	  allows an external monitor to balance memory of many systems.
485	  Everybody who wants to run Linux under VM should select this
486	  option.
487
488config CMM_IUCV
489	bool "IUCV special message interface to cooperative memory management"
490	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
491	help
492	  Select this option to enable the special message interface to
493	  the cooperative memory management.
494
495config APPLDATA_BASE
496	bool "Linux - VM Monitor Stream, base infrastructure"
497	depends on PROC_FS
498	help
499	  This provides a kernel interface for creating and updating z/VM APPLDATA
500	  monitor records. The monitor records are updated at certain time
501	  intervals, once the timer is started.
502	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
503	  i.e. enables or disables monitoring on the Linux side.
504	  A custom interval value (in seconds) can be written to
505	  /proc/appldata/interval.
506
507	  Defaults are 60 seconds interval and timer off.
508	  The /proc entries can also be read from, showing the current settings.
509
510config APPLDATA_MEM
511	tristate "Monitor memory management statistics"
512	depends on APPLDATA_BASE && VM_EVENT_COUNTERS
513	help
514	  This provides memory management related data to the Linux - VM Monitor
515	  Stream, like paging/swapping rate, memory utilisation, etc.
516	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
517	  APPLDATA monitor record, i.e. enables or disables monitoring this record
518	  on the z/VM side.
519
520	  Default is disabled.
521	  The /proc entry can also be read from, showing the current settings.
522
523	  This can also be compiled as a module, which will be called
524	  appldata_mem.o.
525
526config APPLDATA_OS
527	tristate "Monitor OS statistics"
528	depends on APPLDATA_BASE
529	help
530	  This provides OS related data to the Linux - VM Monitor Stream, like
531	  CPU utilisation, etc.
532	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
533	  APPLDATA monitor record, i.e. enables or disables monitoring this record
534	  on the z/VM side.
535
536	  Default is disabled.
537	  This can also be compiled as a module, which will be called
538	  appldata_os.o.
539
540config APPLDATA_NET_SUM
541	tristate "Monitor overall network statistics"
542	depends on APPLDATA_BASE && NET
543	help
544	  This provides network related data to the Linux - VM Monitor Stream,
545	  currently there is only a total sum of network I/O statistics, no
546	  per-interface data.
547	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
548	  APPLDATA monitor record, i.e. enables or disables monitoring this record
549	  on the z/VM side.
550
551	  Default is disabled.
552	  This can also be compiled as a module, which will be called
553	  appldata_net_sum.o.
554
555source kernel/Kconfig.hz
556
557config S390_HYPFS_FS
558	bool "s390 hypervisor file system support"
559	select SYS_HYPERVISOR
560	default y
561	help
562	  This is a virtual file system intended to provide accounting
563	  information in an s390 hypervisor environment.
564
565config KEXEC
566	bool "kexec system call"
567	help
568	  kexec is a system call that implements the ability to shutdown your
569	  current kernel, and to start another kernel.  It is like a reboot
570	  but is independent of hardware/microcode support.
571
572config ZFCPDUMP
573	bool "zfcpdump support"
574	select SMP
575	default n
576	help
577	  Select this option if you want to build an zfcpdump enabled kernel.
578	  Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
579
580config S390_GUEST
581bool "s390 guest support for KVM (EXPERIMENTAL)"
582	depends on 64BIT && EXPERIMENTAL
583	select VIRTIO
584	select VIRTIO_RING
585	select VIRTIO_CONSOLE
586	help
587	  Select this option if you want to run the kernel as a guest under
588	  the KVM hypervisor. This will add detection for KVM as well  as a
589	  virtio transport. If KVM is detected, the virtio console will be
590	  the default console.
591
592config SECCOMP
593	bool "Enable seccomp to safely compute untrusted bytecode"
594	depends on PROC_FS
595	default y
596	help
597	  This kernel feature is useful for number crunching applications
598	  that may need to compute untrusted bytecode during their
599	  execution. By using pipes or other transports made available to
600	  the process as file descriptors supporting the read/write
601	  syscalls, it's possible to isolate those applications in
602	  their own address space using seccomp. Once seccomp is
603	  enabled via /proc/<pid>/seccomp, it cannot be disabled
604	  and the task is only allowed to execute a few safe syscalls
605	  defined by each seccomp mode.
606
607	  If unsure, say Y.
608
609endmenu
610
611menu "Power Management"
612
613source "kernel/power/Kconfig"
614
615endmenu
616
617source "net/Kconfig"
618
619config PCMCIA
620	def_bool n
621
622config CCW
623	def_bool y
624
625source "drivers/Kconfig"
626
627source "fs/Kconfig"
628
629source "arch/s390/Kconfig.debug"
630
631source "security/Kconfig"
632
633source "crypto/Kconfig"
634
635source "lib/Kconfig"
636
637source "arch/s390/kvm/Kconfig"
638