10 config STACKTRACE_SUPPORT
13 config HAVE_LATENCYTOP_SUPPORT
16 config RWSEM_GENERIC_SPINLOCK
19 config RWSEM_XCHGADD_ALGORITHM
22 config ARCH_HAS_ILOG2_U32
25 config ARCH_HAS_ILOG2_U64
28 config GENERIC_HWEIGHT
31 config GENERIC_TIME_VSYSCALL
34 config GENERIC_CLOCKEVENTS
40 config GENERIC_BUG_RELATIVE_POINTERS
49 config ARCH_DMA_ADDR_T_64BIT
52 config GENERIC_LOCKBREAK
53 def_bool y if SMP && PREEMPT
58 config VIRT_CPU_ACCOUNTING
61 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
66 select USE_GENERIC_SMP_HELPERS if SMP
67 select HAVE_SYSCALL_WRAPPERS
68 select HAVE_FUNCTION_TRACER
69 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
70 select HAVE_FTRACE_MCOUNT_RECORD
71 select HAVE_C_RECORDMCOUNT
72 select HAVE_SYSCALL_TRACEPOINTS
73 select HAVE_DYNAMIC_FTRACE
74 select HAVE_FUNCTION_GRAPH_TRACER
75 select HAVE_REGS_AND_STACK_ACCESS_API
78 select HAVE_KRETPROBES
79 select HAVE_KVM if 64BIT
80 select HAVE_ARCH_TRACEHOOK
81 select INIT_ALL_POSSIBLE
83 select HAVE_PERF_EVENTS
84 select ARCH_HAVE_NMI_SAFE_CMPXCHG
85 select HAVE_KERNEL_GZIP
86 select HAVE_KERNEL_BZIP2
87 select HAVE_KERNEL_LZMA
88 select HAVE_KERNEL_LZO
90 select HAVE_GET_USER_PAGES_FAST
91 select HAVE_ARCH_MUTEX_CPU_RELAX
92 select HAVE_ARCH_JUMP_LABEL if !MARCH_G5
93 select HAVE_RCU_TABLE_FREE if SMP
94 select ARCH_INLINE_SPIN_TRYLOCK
95 select ARCH_INLINE_SPIN_TRYLOCK_BH
96 select ARCH_INLINE_SPIN_LOCK
97 select ARCH_INLINE_SPIN_LOCK_BH
98 select ARCH_INLINE_SPIN_LOCK_IRQ
99 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
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_READ_TRYLOCK
105 select ARCH_INLINE_READ_LOCK
106 select ARCH_INLINE_READ_LOCK_BH
107 select ARCH_INLINE_READ_LOCK_IRQ
108 select ARCH_INLINE_READ_LOCK_IRQSAVE
109 select ARCH_INLINE_READ_UNLOCK
110 select ARCH_INLINE_READ_UNLOCK_BH
111 select ARCH_INLINE_READ_UNLOCK_IRQ
112 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
113 select ARCH_INLINE_WRITE_TRYLOCK
114 select ARCH_INLINE_WRITE_LOCK
115 select ARCH_INLINE_WRITE_LOCK_BH
116 select ARCH_INLINE_WRITE_LOCK_IRQ
117 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
118 select ARCH_INLINE_WRITE_UNLOCK
119 select ARCH_INLINE_WRITE_UNLOCK_BH
120 select ARCH_INLINE_WRITE_UNLOCK_IRQ
121 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
123 config SCHED_OMIT_FRAME_POINTER
126 source "init/Kconfig"
128 source "kernel/Kconfig.freezer"
132 comment "Processor type and features"
134 source "kernel/time/Kconfig"
138 prompt "64 bit kernel"
140 Select this option if you have an IBM z/Architecture machine
141 and want to use the 64 bit addressing mode.
151 prompt "Symmetric multi-processing support"
153 This enables support for systems with more than one CPU. If you have
154 a system with only one CPU, like most personal computers, say N. If
155 you have a system with more than one CPU, say Y.
157 If you say N here, the kernel will run on single and multiprocessor
158 machines, but will use only one CPU of a multiprocessor machine. If
159 you say Y here, the kernel will run on many, but not all,
160 singleprocessor machines. On a singleprocessor machine, the kernel
161 will run faster if you say N here.
163 See also the SMP-HOWTO available at
164 <http://www.tldp.org/docs.html#howto>.
166 Even if you don't know what to do here, say Y.
169 int "Maximum number of CPUs (2-64)"
172 default "32" if !64BIT
173 default "64" if 64BIT
175 This allows you to specify the maximum number of CPUs which this
176 kernel will support. The maximum supported value is 64 and the
177 minimum value which makes sense is 2.
179 This is purely to save memory - each supported CPU adds
180 approximately sixteen kilobytes to the kernel image.
184 prompt "Support for hot-pluggable CPUs"
188 Say Y here to be able to turn CPUs off and on. CPUs
189 can be controlled through /sys/devices/system/cpu/cpu#.
190 Say N if you want to disable CPU hotplug.
194 prompt "Multi-core scheduler support"
197 Multi-core scheduler support improves the CPU scheduler's decision
198 making when dealing with multi-core CPU chips at a cost of slightly
199 increased overhead in some places.
203 prompt "Book scheduler support"
204 depends on SMP && SCHED_MC
206 Book scheduler support improves the CPU scheduler's decision making
207 when dealing with machines that have several books.
211 prompt "IEEE FPU emulation"
214 This option is required for IEEE compliant floating point arithmetic
215 on older ESA/390 machines. Say Y unless you know your machine doesn't
220 prompt "Kernel support for 31 bit emulation"
222 select COMPAT_BINFMT_ELF
224 Select this option if you want to enable your system kernel to
225 handle system-calls from ELF binaries for 31 bit ESA. This option
226 (and some other stuff like libraries and such) is needed for
227 executing 31 bit applications. It is safe to say "Y".
229 config SYSVIPC_COMPAT
230 def_bool y if COMPAT && SYSVIPC
235 comment "Code generation options"
238 prompt "Processor type"
242 bool "System/390 model G5 and G6"
245 Select this to build a 31 bit kernel that works
246 on all ESA/390 and z/Architecture machines.
249 bool "IBM zSeries model z800 and z900"
251 Select this to enable optimizations for model z800/z900 (2064 and
252 2066 series). This will enable some optimizations that are not
253 available on older ESA/390 (31 Bit) only CPUs.
256 bool "IBM zSeries model z890 and z990"
258 Select this to enable optimizations for model z890/z990 (2084 and
259 2086 series). The kernel will be slightly faster but will not work
265 Select this to enable optimizations for IBM System z9 (2094 and
266 2096 series). The kernel will be slightly faster but will not work
270 bool "IBM System z10"
272 Select this to enable optimizations for IBM System z10 (2097 and
273 2098 series). The kernel will be slightly faster but will not work
277 bool "IBM zEnterprise 114 and 196"
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.
287 prompt "Pack kernel stack"
289 This option enables the compiler option -mkernel-backchain if it
290 is available. If the option is available the compiler supports
291 the new stack layout which dramatically reduces the minimum stack
292 frame size. With an old compiler a non-leaf function needs a
293 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
294 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
295 and 24 byte on 64 bit.
297 Say Y if you are unsure.
301 prompt "Use 8kb for kernel stack instead of 16kb"
302 depends on PACK_STACK && 64BIT && !LOCKDEP
304 If you say Y here and the compiler supports the -mkernel-backchain
305 option the kernel will use a smaller kernel stack size. The reduced
306 size is 8kb instead of 16kb. This allows to run more threads on a
307 system and reduces the pressure on the memory management for higher
308 order page allocations.
310 Say N if you are unsure.
314 prompt "Detect kernel stack overflow"
316 This option enables the compiler option -mstack-guard and
317 -mstack-size if they are available. If the compiler supports them
318 it will emit additional code to each function prolog to trigger
319 an illegal operation if the kernel stack is about to overflow.
321 Say N if you are unsure.
324 int "Size of the guard area (128-1024)"
326 depends on CHECK_STACK
329 This allows you to specify the size of the guard area at the lower
330 end of the kernel stack. If the kernel stack points into the guard
331 area on function entry an illegal operation is triggered. The size
332 needs to be a power of 2. Please keep in mind that the size of an
333 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
334 The minimum size for the stack guard should be 256 for 31 bit and
337 config WARN_DYNAMIC_STACK
339 prompt "Emit compiler warnings for function with dynamic stack usage"
341 This option enables the compiler option -mwarn-dynamicstack. If the
342 compiler supports this options generates warnings for functions
343 that dynamically allocate stack space using alloca.
345 Say N if you are unsure.
347 config ARCH_POPULATES_NODE_MAP
350 comment "Kernel preemption"
352 source "kernel/Kconfig.preempt"
354 config ARCH_SPARSEMEM_ENABLE
356 select SPARSEMEM_VMEMMAP_ENABLE
357 select SPARSEMEM_VMEMMAP
358 select SPARSEMEM_STATIC if !64BIT
360 config ARCH_SPARSEMEM_DEFAULT
363 config ARCH_SELECT_MEMORY_MODEL
366 config ARCH_ENABLE_MEMORY_HOTPLUG
367 def_bool y if SPARSEMEM
369 config ARCH_ENABLE_MEMORY_HOTREMOVE
372 config ARCH_HIBERNATION_POSSIBLE
377 comment "I/O subsystem configuration"
381 prompt "QDIO support"
383 This driver provides the Queued Direct I/O base support for
386 To compile this driver as a module, choose M here: the
387 module will be called qdio.
393 prompt "Support for CHSC subchannels"
395 This driver allows usage of CHSC subchannels. A CHSC subchannel
396 is usually present on LPAR only.
397 The driver creates a device /dev/chsc, which may be used to
398 obtain I/O configuration information about the machine and
399 to issue asynchronous chsc commands (DANGEROUS).
400 You will usually only want to use this interface on a special
401 LPAR designated for system management.
403 To compile this driver as a module, choose M here: the
404 module will be called chsc_sch.
412 prompt "Builtin IPL record support"
414 If you want to use the produced kernel to IPL directly from a
415 device, you have to merge a bootsector specific to the device
416 into the first bytes of the kernel. You will have to select the
420 prompt "IPL method generated into head.S"
424 Select "tape" if you want to IPL the image from a Tape.
426 Select "vm_reader" if you are running under VM/ESA and want
427 to IPL the image from the emulated card reader.
437 source "fs/Kconfig.binfmt"
439 config FORCE_MAX_ZONEORDER
445 prompt "Pseudo page fault support"
447 Select this option, if you want to use PFAULT pseudo page fault
448 handling under VM. If running native or in LPAR, this option
449 has no effect. If your VM does not support PFAULT, PAGEEX
450 pseudo page fault handling will be used.
451 Note that VM 4.2 supports PFAULT but has a bug in its
452 implementation that causes some problems.
453 Everybody who wants to run Linux under VM != VM4.2 should select
458 prompt "VM shared kernel support"
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
465 You should only select this option if you know what you are
466 doing and want to exploit this feature.
470 prompt "Cooperative memory management"
472 Select this option, if you want to enable the kernel interface
473 to reduce the memory size of the system. This is accomplished
474 by allocating pages of memory and put them "on hold". This only
475 makes sense for a system running under VM where the unused pages
476 will be reused by VM for other guest systems. The interface
477 allows an external monitor to balance memory of many systems.
478 Everybody who wants to run Linux under VM should select this
483 prompt "IUCV special message interface to cooperative memory management"
484 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
486 Select this option to enable the special message interface to
487 the cooperative memory management.
491 prompt "Linux - VM Monitor Stream, base infrastructure"
494 This provides a kernel interface for creating and updating z/VM APPLDATA
495 monitor records. The monitor records are updated at certain time
496 intervals, once the timer is started.
497 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
498 i.e. enables or disables monitoring on the Linux side.
499 A custom interval value (in seconds) can be written to
500 /proc/appldata/interval.
502 Defaults are 60 seconds interval and timer off.
503 The /proc entries can also be read from, showing the current settings.
507 prompt "Monitor memory management statistics"
508 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
510 This provides memory management related data to the Linux - VM Monitor
511 Stream, like paging/swapping rate, memory utilisation, etc.
512 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
513 APPLDATA monitor record, i.e. enables or disables monitoring this record
517 The /proc entry can also be read from, showing the current settings.
519 This can also be compiled as a module, which will be called
524 prompt "Monitor OS statistics"
525 depends on APPLDATA_BASE
527 This provides OS related data to the Linux - VM Monitor Stream, like
528 CPU utilisation, etc.
529 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
530 APPLDATA monitor record, i.e. enables or disables monitoring this record
534 This can also be compiled as a module, which will be called
537 config APPLDATA_NET_SUM
539 prompt "Monitor overall network statistics"
540 depends on APPLDATA_BASE && NET
542 This provides network related data to the Linux - VM Monitor Stream,
543 currently there is only a total sum of network I/O statistics, no
545 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
546 APPLDATA monitor record, i.e. enables or disables monitoring this record
550 This can also be compiled as a module, which will be called
553 source kernel/Kconfig.hz
557 prompt "s390 hypervisor file system support"
558 select SYS_HYPERVISOR
560 This is a virtual file system intended to provide accounting
561 information in an s390 hypervisor environment.
565 prompt "kexec system call"
567 kexec is a system call that implements the ability to shutdown your
568 current kernel, and to start another kernel. It is like a reboot
569 but is independent of hardware/microcode support.
573 prompt "zfcpdump support"
576 Select this option if you want to build an zfcpdump enabled kernel.
577 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
581 prompt "s390 guest support for KVM (EXPERIMENTAL)"
582 depends on 64BIT && EXPERIMENTAL
583 select VIRTUALIZATION
586 select VIRTIO_CONSOLE
588 Select this option if you want to run the kernel as a guest under
589 the KVM hypervisor. This will add detection for KVM as well as a
590 virtio transport. If KVM is detected, the virtio console will be
595 prompt "Enable seccomp to safely compute untrusted bytecode"
598 This kernel feature is useful for number crunching applications
599 that may need to compute untrusted bytecode during their
600 execution. By using pipes or other transports made available to
601 the process as file descriptors supporting the read/write
602 syscalls, it's possible to isolate those applications in
603 their own address space using seccomp. Once seccomp is
604 enabled via /proc/<pid>/seccomp, it cannot be disabled
605 and the task is only allowed to execute a few safe syscalls
606 defined by each seccomp mode.
612 menu "Power Management"
614 source "kernel/power/Kconfig"
626 source "drivers/Kconfig"
630 source "arch/s390/Kconfig.debug"
632 source "security/Kconfig"
634 source "crypto/Kconfig"
638 source "arch/s390/kvm/Kconfig"