xref: /linux/arch/s390/Kconfig (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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_PERF_EVENTS
99	select HAVE_KERNEL_GZIP
100	select HAVE_KERNEL_BZIP2
101	select HAVE_KERNEL_LZMA
102	select HAVE_KERNEL_LZO
103	select ARCH_INLINE_SPIN_TRYLOCK
104	select ARCH_INLINE_SPIN_TRYLOCK_BH
105	select ARCH_INLINE_SPIN_LOCK
106	select ARCH_INLINE_SPIN_LOCK_BH
107	select ARCH_INLINE_SPIN_LOCK_IRQ
108	select ARCH_INLINE_SPIN_LOCK_IRQSAVE
109	select ARCH_INLINE_SPIN_UNLOCK
110	select ARCH_INLINE_SPIN_UNLOCK_BH
111	select ARCH_INLINE_SPIN_UNLOCK_IRQ
112	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
113	select ARCH_INLINE_READ_TRYLOCK
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_UNLOCK
119	select ARCH_INLINE_READ_UNLOCK_BH
120	select ARCH_INLINE_READ_UNLOCK_IRQ
121	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
122	select ARCH_INLINE_WRITE_TRYLOCK
123	select ARCH_INLINE_WRITE_LOCK
124	select ARCH_INLINE_WRITE_LOCK_BH
125	select ARCH_INLINE_WRITE_LOCK_IRQ
126	select ARCH_INLINE_WRITE_LOCK_IRQSAVE
127	select ARCH_INLINE_WRITE_UNLOCK
128	select ARCH_INLINE_WRITE_UNLOCK_BH
129	select ARCH_INLINE_WRITE_UNLOCK_IRQ
130	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
131
132config SCHED_OMIT_FRAME_POINTER
133	bool
134	default y
135
136source "init/Kconfig"
137
138source "kernel/Kconfig.freezer"
139
140menu "Base setup"
141
142comment "Processor type and features"
143
144source "kernel/time/Kconfig"
145
146config 64BIT
147	bool "64 bit kernel"
148	help
149	  Select this option if you have a 64 bit IBM zSeries machine
150	  and want to use the 64 bit addressing mode.
151
152config 32BIT
153	bool
154	default y if !64BIT
155
156config KTIME_SCALAR
157	def_bool 32BIT
158
159config SMP
160	bool "Symmetric multi-processing support"
161	---help---
162	  This enables support for systems with more than one CPU. If you have
163	  a system with only one CPU, like most personal computers, say N. If
164	  you have a system with more than one CPU, say Y.
165
166	  If you say N here, the kernel will run on single and multiprocessor
167	  machines, but will use only one CPU of a multiprocessor machine. If
168	  you say Y here, the kernel will run on many, but not all,
169	  singleprocessor machines. On a singleprocessor machine, the kernel
170	  will run faster if you say N here.
171
172	  See also the SMP-HOWTO available at
173	  <http://www.tldp.org/docs.html#howto>.
174
175	  Even if you don't know what to do here, say Y.
176
177config NR_CPUS
178	int "Maximum number of CPUs (2-64)"
179	range 2 64
180	depends on SMP
181	default "32" if !64BIT
182	default "64" if 64BIT
183	help
184	  This allows you to specify the maximum number of CPUs which this
185	  kernel will support.  The maximum supported value is 64 and the
186	  minimum value which makes sense is 2.
187
188	  This is purely to save memory - each supported CPU adds
189	  approximately sixteen kilobytes to the kernel image.
190
191config HOTPLUG_CPU
192	bool "Support for hot-pluggable CPUs"
193	depends on SMP
194	select HOTPLUG
195	default n
196	help
197	  Say Y here to be able to turn CPUs off and on. CPUs
198	  can be controlled through /sys/devices/system/cpu/cpu#.
199	  Say N if you want to disable CPU hotplug.
200
201config MATHEMU
202	bool "IEEE FPU emulation"
203	depends on MARCH_G5
204	help
205	  This option is required for IEEE compliant floating point arithmetic
206	  on older S/390 machines. Say Y unless you know your machine doesn't
207	  need this.
208
209config COMPAT
210	bool "Kernel support for 31 bit emulation"
211	depends on 64BIT
212	select COMPAT_BINFMT_ELF
213	help
214	  Select this option if you want to enable your system kernel to
215	  handle system-calls from ELF binaries for 31 bit ESA.  This option
216	  (and some other stuff like libraries and such) is needed for
217	  executing 31 bit applications.  It is safe to say "Y".
218
219config SYSVIPC_COMPAT
220	bool
221	depends on COMPAT && SYSVIPC
222	default y
223
224config AUDIT_ARCH
225	bool
226	default y
227
228config S390_EXEC_PROTECT
229	bool "Data execute protection"
230	help
231	  This option allows to enable a buffer overflow protection for user
232	  space programs and it also selects the addressing mode option above.
233	  The kernel parameter noexec=on will enable this feature and also
234	  switch the addressing modes, default is disabled. Enabling this (via
235	  kernel parameter) on machines earlier than IBM System z9-109 EC/BC
236	  will reduce system performance.
237
238comment "Code generation options"
239
240choice
241	prompt "Processor type"
242	default MARCH_G5
243
244config MARCH_G5
245	bool "S/390 model G5 and G6"
246	depends on !64BIT
247	help
248	  Select this to build a 31 bit kernel that works
249	  on all S/390 and zSeries machines.
250
251config MARCH_Z900
252	bool "IBM eServer zSeries model z800 and z900"
253	help
254	  Select this to optimize for zSeries machines. This
255	  will enable some optimizations that are not available
256	  on older 31 bit only CPUs.
257
258config MARCH_Z990
259	bool "IBM eServer zSeries model z890 and z990"
260	help
261	  Select this enable optimizations for model z890/z990.
262	  This will be slightly faster but does not work on
263	  older machines such as the z900.
264
265config MARCH_Z9_109
266	bool "IBM System z9"
267	help
268	  Select this to enable optimizations for IBM System z9-109, IBM
269	  System z9 Enterprise Class (z9 EC), and IBM System z9 Business
270	  Class (z9 BC). The kernel will be slightly faster but will not
271	  work on older machines such as the z990, z890, z900, and z800.
272
273config MARCH_Z10
274	bool "IBM System z10"
275	help
276	  Select this to enable optimizations for IBM System z10. The
277	  kernel will be slightly faster but will not work on older
278	  machines such as the z990, z890, z900, z800, z9-109, z9-ec
279	  and z9-bc.
280
281endchoice
282
283config PACK_STACK
284	bool "Pack kernel stack"
285	help
286	  This option enables the compiler option -mkernel-backchain if it
287	  is available. If the option is available the compiler supports
288	  the new stack layout which dramatically reduces the minimum stack
289	  frame size. With an old compiler a non-leaf function needs a
290	  minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
291	  -mkernel-backchain the minimum size drops to 16 byte on 31 bit
292	  and 24 byte on 64 bit.
293
294	  Say Y if you are unsure.
295
296config SMALL_STACK
297	bool "Use 8kb for kernel stack instead of 16kb"
298	depends on PACK_STACK && 64BIT && !LOCKDEP
299	help
300	  If you say Y here and the compiler supports the -mkernel-backchain
301	  option the kernel will use a smaller kernel stack size. The reduced
302	  size is 8kb instead of 16kb. This allows to run more threads on a
303	  system and reduces the pressure on the memory management for higher
304	  order page allocations.
305
306	  Say N if you are unsure.
307
308config CHECK_STACK
309	bool "Detect kernel stack overflow"
310	help
311	  This option enables the compiler option -mstack-guard and
312	  -mstack-size if they are available. If the compiler supports them
313	  it will emit additional code to each function prolog to trigger
314	  an illegal operation if the kernel stack is about to overflow.
315
316	  Say N if you are unsure.
317
318config STACK_GUARD
319	int "Size of the guard area (128-1024)"
320	range 128 1024
321	depends on CHECK_STACK
322	default "256"
323	help
324	  This allows you to specify the size of the guard area at the lower
325	  end of the kernel stack. If the kernel stack points into the guard
326	  area on function entry an illegal operation is triggered. The size
327	  needs to be a power of 2. Please keep in mind that the size of an
328	  interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
329	  The minimum size for the stack guard should be 256 for 31 bit and
330	  512 for 64 bit.
331
332config WARN_STACK
333	bool "Emit compiler warnings for function with broken stack usage"
334	help
335	  This option enables the compiler options -mwarn-framesize and
336	  -mwarn-dynamicstack. If the compiler supports these options it
337	  will generate warnings for function which either use alloca or
338	  create a stack frame bigger than CONFIG_WARN_STACK_SIZE.
339
340	  Say N if you are unsure.
341
342config WARN_STACK_SIZE
343	int "Maximum frame size considered safe (128-2048)"
344	range 128 2048
345	depends on WARN_STACK
346	default "2048"
347	help
348	  This allows you to specify the maximum frame size a function may
349	  have without the compiler complaining about it.
350
351config ARCH_POPULATES_NODE_MAP
352	def_bool y
353
354comment "Kernel preemption"
355
356source "kernel/Kconfig.preempt"
357
358config ARCH_SPARSEMEM_ENABLE
359	def_bool y
360	select SPARSEMEM_VMEMMAP_ENABLE
361	select SPARSEMEM_VMEMMAP
362	select SPARSEMEM_STATIC if !64BIT
363
364config ARCH_SPARSEMEM_DEFAULT
365	def_bool y
366
367config ARCH_SELECT_MEMORY_MODEL
368       def_bool y
369
370config ARCH_ENABLE_MEMORY_HOTPLUG
371	def_bool y
372	depends on SPARSEMEM
373
374config ARCH_ENABLE_MEMORY_HOTREMOVE
375	def_bool y
376
377config ARCH_HIBERNATION_POSSIBLE
378       def_bool y if 64BIT
379
380source "mm/Kconfig"
381
382comment "I/O subsystem configuration"
383
384config QDIO
385	tristate "QDIO support"
386	---help---
387	  This driver provides the Queued Direct I/O base support for
388	  IBM System z.
389
390	  To compile this driver as a module, choose M here: the
391	  module will be called qdio.
392
393	  If unsure, say Y.
394
395config CHSC_SCH
396	tristate "Support for CHSC subchannels"
397	help
398	  This driver allows usage of CHSC subchannels. A CHSC subchannel
399	  is usually present on LPAR only.
400	  The driver creates a device /dev/chsc, which may be used to
401	  obtain I/O configuration information about the machine and
402	  to issue asynchronous chsc commands (DANGEROUS).
403	  You will usually only want to use this interface on a special
404	  LPAR designated for system management.
405
406	  To compile this driver as a module, choose M here: the
407	  module will be called chsc_sch.
408
409	  If unsure, say N.
410
411comment "Misc"
412
413config IPL
414	bool "Builtin IPL record support"
415	help
416	  If you want to use the produced kernel to IPL directly from a
417	  device, you have to merge a bootsector specific to the device
418	  into the first bytes of the kernel. You will have to select the
419	  IPL device.
420
421choice
422	prompt "IPL method generated into head.S"
423	depends on IPL
424	default IPL_VM
425	help
426	  Select "tape" if you want to IPL the image from a Tape.
427
428	  Select "vm_reader" if you are running under VM/ESA and want
429	  to IPL the image from the emulated card reader.
430
431config IPL_TAPE
432	bool "tape"
433
434config IPL_VM
435	bool "vm_reader"
436
437endchoice
438
439source "fs/Kconfig.binfmt"
440
441config FORCE_MAX_ZONEORDER
442	int
443	default "9"
444
445config PFAULT
446	bool "Pseudo page fault support"
447	help
448	  Select this option, if you want to use PFAULT pseudo page fault
449	  handling under VM. If running native or in LPAR, this option
450	  has no effect. If your VM does not support PFAULT, PAGEEX
451	  pseudo page fault handling will be used.
452	  Note that VM 4.2 supports PFAULT but has a bug in its
453	  implementation that causes some problems.
454	  Everybody who wants to run Linux under VM != VM4.2 should select
455	  this option.
456
457config SHARED_KERNEL
458	bool "VM shared kernel support"
459	help
460	  Select this option, if you want to share the text segment of the
461	  Linux kernel between different VM guests. This reduces memory
462	  usage with lots of guests but greatly increases kernel size.
463	  Also if a kernel was IPL'ed from a shared segment the kexec system
464	  call will not work.
465	  You should only select this option if you know what you are
466	  doing and want to exploit this feature.
467
468config CMM
469	tristate "Cooperative memory management"
470	help
471	  Select this option, if you want to enable the kernel interface
472	  to reduce the memory size of the system. This is accomplished
473	  by allocating pages of memory and put them "on hold". This only
474	  makes sense for a system running under VM where the unused pages
475	  will be reused by VM for other guest systems. The interface
476	  allows an external monitor to balance memory of many systems.
477	  Everybody who wants to run Linux under VM should select this
478	  option.
479
480config CMM_IUCV
481	bool "IUCV special message interface to cooperative memory management"
482	depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
483	help
484	  Select this option to enable the special message interface to
485	  the cooperative memory management.
486
487config APPLDATA_BASE
488	bool "Linux - VM Monitor Stream, base infrastructure"
489	depends on PROC_FS
490	help
491	  This provides a kernel interface for creating and updating z/VM APPLDATA
492	  monitor records. The monitor records are updated at certain time
493	  intervals, once the timer is started.
494	  Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
495	  i.e. enables or disables monitoring on the Linux side.
496	  A custom interval value (in seconds) can be written to
497	  /proc/appldata/interval.
498
499	  Defaults are 60 seconds interval and timer off.
500	  The /proc entries can also be read from, showing the current settings.
501
502config APPLDATA_MEM
503	tristate "Monitor memory management statistics"
504	depends on APPLDATA_BASE && VM_EVENT_COUNTERS
505	help
506	  This provides memory management related data to the Linux - VM Monitor
507	  Stream, like paging/swapping rate, memory utilisation, etc.
508	  Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
509	  APPLDATA monitor record, i.e. enables or disables monitoring this record
510	  on the z/VM side.
511
512	  Default is disabled.
513	  The /proc entry can also be read from, showing the current settings.
514
515	  This can also be compiled as a module, which will be called
516	  appldata_mem.o.
517
518config APPLDATA_OS
519	tristate "Monitor OS statistics"
520	depends on APPLDATA_BASE
521	help
522	  This provides OS related data to the Linux - VM Monitor Stream, like
523	  CPU utilisation, etc.
524	  Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
525	  APPLDATA monitor record, i.e. enables or disables monitoring this record
526	  on the z/VM side.
527
528	  Default is disabled.
529	  This can also be compiled as a module, which will be called
530	  appldata_os.o.
531
532config APPLDATA_NET_SUM
533	tristate "Monitor overall network statistics"
534	depends on APPLDATA_BASE && NET
535	help
536	  This provides network related data to the Linux - VM Monitor Stream,
537	  currently there is only a total sum of network I/O statistics, no
538	  per-interface data.
539	  Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
540	  APPLDATA monitor record, i.e. enables or disables monitoring this record
541	  on the z/VM side.
542
543	  Default is disabled.
544	  This can also be compiled as a module, which will be called
545	  appldata_net_sum.o.
546
547source kernel/Kconfig.hz
548
549config S390_HYPFS_FS
550	bool "s390 hypervisor file system support"
551	select SYS_HYPERVISOR
552	default y
553	help
554	  This is a virtual file system intended to provide accounting
555	  information in an s390 hypervisor environment.
556
557config KEXEC
558	bool "kexec system call"
559	help
560	  kexec is a system call that implements the ability to shutdown your
561	  current kernel, and to start another kernel.  It is like a reboot
562	  but is independent of hardware/microcode support.
563
564config ZFCPDUMP
565	bool "zfcpdump support"
566	select SMP
567	default n
568	help
569	  Select this option if you want to build an zfcpdump enabled kernel.
570	  Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
571
572config S390_GUEST
573bool "s390 guest support for KVM (EXPERIMENTAL)"
574	depends on 64BIT && EXPERIMENTAL
575	select VIRTIO
576	select VIRTIO_RING
577	select VIRTIO_CONSOLE
578	help
579	  Select this option if you want to run the kernel as a guest under
580	  the KVM hypervisor. This will add detection for KVM as well  as a
581	  virtio transport. If KVM is detected, the virtio console will be
582	  the default console.
583
584config SECCOMP
585	bool "Enable seccomp to safely compute untrusted bytecode"
586	depends on PROC_FS
587	default y
588	help
589	  This kernel feature is useful for number crunching applications
590	  that may need to compute untrusted bytecode during their
591	  execution. By using pipes or other transports made available to
592	  the process as file descriptors supporting the read/write
593	  syscalls, it's possible to isolate those applications in
594	  their own address space using seccomp. Once seccomp is
595	  enabled via /proc/<pid>/seccomp, it cannot be disabled
596	  and the task is only allowed to execute a few safe syscalls
597	  defined by each seccomp mode.
598
599	  If unsure, say Y.
600
601endmenu
602
603menu "Power Management"
604
605source "kernel/power/Kconfig"
606
607endmenu
608
609source "net/Kconfig"
610
611config PCMCIA
612	def_bool n
613
614config CCW
615	def_bool y
616
617source "drivers/Kconfig"
618
619source "fs/Kconfig"
620
621source "arch/s390/Kconfig.debug"
622
623source "security/Kconfig"
624
625source "crypto/Kconfig"
626
627source "lib/Kconfig"
628
629source "arch/s390/kvm/Kconfig"
630