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 HAVE_KERNEL_GZIP
85 select HAVE_KERNEL_BZIP2
86 select HAVE_KERNEL_LZMA
87 select HAVE_KERNEL_LZO
89 select HAVE_GET_USER_PAGES_FAST
90 select HAVE_ARCH_MUTEX_CPU_RELAX
91 select HAVE_ARCH_JUMP_LABEL if !MARCH_G5
92 select ARCH_INLINE_SPIN_TRYLOCK
93 select ARCH_INLINE_SPIN_TRYLOCK_BH
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_UNLOCK
99 select ARCH_INLINE_SPIN_UNLOCK_BH
100 select ARCH_INLINE_SPIN_UNLOCK_IRQ
101 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
102 select ARCH_INLINE_READ_TRYLOCK
103 select ARCH_INLINE_READ_LOCK
104 select ARCH_INLINE_READ_LOCK_BH
105 select ARCH_INLINE_READ_LOCK_IRQ
106 select ARCH_INLINE_READ_LOCK_IRQSAVE
107 select ARCH_INLINE_READ_UNLOCK
108 select ARCH_INLINE_READ_UNLOCK_BH
109 select ARCH_INLINE_READ_UNLOCK_IRQ
110 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
111 select ARCH_INLINE_WRITE_TRYLOCK
112 select ARCH_INLINE_WRITE_LOCK
113 select ARCH_INLINE_WRITE_LOCK_BH
114 select ARCH_INLINE_WRITE_LOCK_IRQ
115 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
116 select ARCH_INLINE_WRITE_UNLOCK
117 select ARCH_INLINE_WRITE_UNLOCK_BH
118 select ARCH_INLINE_WRITE_UNLOCK_IRQ
119 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
121 config SCHED_OMIT_FRAME_POINTER
124 source "init/Kconfig"
126 source "kernel/Kconfig.freezer"
130 comment "Processor type and features"
132 source "kernel/time/Kconfig"
136 prompt "64 bit kernel"
138 Select this option if you have an IBM z/Architecture machine
139 and want to use the 64 bit addressing mode.
149 prompt "Symmetric multi-processing support"
151 This enables support for systems with more than one CPU. If you have
152 a system with only one CPU, like most personal computers, say N. If
153 you have a system with more than one CPU, say Y.
155 If you say N here, the kernel will run on single and multiprocessor
156 machines, but will use only one CPU of a multiprocessor machine. If
157 you say Y here, the kernel will run on many, but not all,
158 singleprocessor machines. On a singleprocessor machine, the kernel
159 will run faster if you say N here.
161 See also the SMP-HOWTO available at
162 <http://www.tldp.org/docs.html#howto>.
164 Even if you don't know what to do here, say Y.
167 int "Maximum number of CPUs (2-64)"
170 default "32" if !64BIT
171 default "64" if 64BIT
173 This allows you to specify the maximum number of CPUs which this
174 kernel will support. The maximum supported value is 64 and the
175 minimum value which makes sense is 2.
177 This is purely to save memory - each supported CPU adds
178 approximately sixteen kilobytes to the kernel image.
182 prompt "Support for hot-pluggable CPUs"
186 Say Y here to be able to turn CPUs off and on. CPUs
187 can be controlled through /sys/devices/system/cpu/cpu#.
188 Say N if you want to disable CPU hotplug.
192 prompt "Multi-core scheduler support"
195 Multi-core scheduler support improves the CPU scheduler's decision
196 making when dealing with multi-core CPU chips at a cost of slightly
197 increased overhead in some places.
201 prompt "Book scheduler support"
202 depends on SMP && SCHED_MC
204 Book scheduler support improves the CPU scheduler's decision making
205 when dealing with machines that have several books.
209 prompt "IEEE FPU emulation"
212 This option is required for IEEE compliant floating point arithmetic
213 on older ESA/390 machines. Say Y unless you know your machine doesn't
218 prompt "Kernel support for 31 bit emulation"
220 select COMPAT_BINFMT_ELF
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".
227 config SYSVIPC_COMPAT
228 def_bool y if COMPAT && SYSVIPC
233 config S390_EXEC_PROTECT
235 prompt "Data execute protection"
237 This option allows to enable a buffer overflow protection for user
238 space programs and it also selects the addressing mode option above.
239 The kernel parameter noexec=on will enable this feature and also
240 switch the addressing modes, default is disabled. Enabling this (via
241 kernel parameter) on machines earlier than IBM System z9 this will
242 reduce system performance.
244 comment "Code generation options"
247 prompt "Processor type"
251 bool "System/390 model G5 and G6"
254 Select this to build a 31 bit kernel that works
255 on all ESA/390 and z/Architecture machines.
258 bool "IBM zSeries model z800 and z900"
260 Select this to enable optimizations for model z800/z900 (2064 and
261 2066 series). This will enable some optimizations that are not
262 available on older ESA/390 (31 Bit) only CPUs.
265 bool "IBM zSeries model z890 and z990"
267 Select this to enable optimizations for model z890/z990 (2084 and
268 2086 series). The kernel will be slightly faster but will not work
274 Select this to enable optimizations for IBM System z9 (2094 and
275 2096 series). The kernel will be slightly faster but will not work
279 bool "IBM System z10"
281 Select this to enable optimizations for IBM System z10 (2097 and
282 2098 series). The kernel will be slightly faster but will not work
286 bool "IBM zEnterprise 196"
288 Select this to enable optimizations for IBM zEnterprise 196
289 (2817 series). The kernel will be slightly faster but will not work
296 prompt "Pack kernel stack"
298 This option enables the compiler option -mkernel-backchain if it
299 is available. If the option is available the compiler supports
300 the new stack layout which dramatically reduces the minimum stack
301 frame size. With an old compiler a non-leaf function needs a
302 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
303 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
304 and 24 byte on 64 bit.
306 Say Y if you are unsure.
310 prompt "Use 8kb for kernel stack instead of 16kb"
311 depends on PACK_STACK && 64BIT && !LOCKDEP
313 If you say Y here and the compiler supports the -mkernel-backchain
314 option the kernel will use a smaller kernel stack size. The reduced
315 size is 8kb instead of 16kb. This allows to run more threads on a
316 system and reduces the pressure on the memory management for higher
317 order page allocations.
319 Say N if you are unsure.
323 prompt "Detect kernel stack overflow"
325 This option enables the compiler option -mstack-guard and
326 -mstack-size if they are available. If the compiler supports them
327 it will emit additional code to each function prolog to trigger
328 an illegal operation if the kernel stack is about to overflow.
330 Say N if you are unsure.
333 int "Size of the guard area (128-1024)"
335 depends on CHECK_STACK
338 This allows you to specify the size of the guard area at the lower
339 end of the kernel stack. If the kernel stack points into the guard
340 area on function entry an illegal operation is triggered. The size
341 needs to be a power of 2. Please keep in mind that the size of an
342 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
343 The minimum size for the stack guard should be 256 for 31 bit and
346 config WARN_DYNAMIC_STACK
348 prompt "Emit compiler warnings for function with dynamic stack usage"
350 This option enables the compiler option -mwarn-dynamicstack. If the
351 compiler supports this options generates warnings for functions
352 that dynamically allocate stack space using alloca.
354 Say N if you are unsure.
356 config ARCH_POPULATES_NODE_MAP
359 comment "Kernel preemption"
361 source "kernel/Kconfig.preempt"
363 config ARCH_SPARSEMEM_ENABLE
365 select SPARSEMEM_VMEMMAP_ENABLE
366 select SPARSEMEM_VMEMMAP
367 select SPARSEMEM_STATIC if !64BIT
369 config ARCH_SPARSEMEM_DEFAULT
372 config ARCH_SELECT_MEMORY_MODEL
375 config ARCH_ENABLE_MEMORY_HOTPLUG
376 def_bool y if SPARSEMEM
378 config ARCH_ENABLE_MEMORY_HOTREMOVE
381 config ARCH_HIBERNATION_POSSIBLE
386 comment "I/O subsystem configuration"
390 prompt "QDIO support"
392 This driver provides the Queued Direct I/O base support for
395 To compile this driver as a module, choose M here: the
396 module will be called qdio.
402 prompt "Support for CHSC subchannels"
404 This driver allows usage of CHSC subchannels. A CHSC subchannel
405 is usually present on LPAR only.
406 The driver creates a device /dev/chsc, which may be used to
407 obtain I/O configuration information about the machine and
408 to issue asynchronous chsc commands (DANGEROUS).
409 You will usually only want to use this interface on a special
410 LPAR designated for system management.
412 To compile this driver as a module, choose M here: the
413 module will be called chsc_sch.
421 prompt "Builtin IPL record support"
423 If you want to use the produced kernel to IPL directly from a
424 device, you have to merge a bootsector specific to the device
425 into the first bytes of the kernel. You will have to select the
429 prompt "IPL method generated into head.S"
433 Select "tape" if you want to IPL the image from a Tape.
435 Select "vm_reader" if you are running under VM/ESA and want
436 to IPL the image from the emulated card reader.
446 source "fs/Kconfig.binfmt"
448 config FORCE_MAX_ZONEORDER
454 prompt "Pseudo page fault support"
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
467 prompt "VM shared kernel support"
469 Select this option, if you want to share the text segment of the
470 Linux kernel between different VM guests. This reduces memory
471 usage with lots of guests but greatly increases kernel size.
472 Also if a kernel was IPL'ed from a shared segment the kexec system
474 You should only select this option if you know what you are
475 doing and want to exploit this feature.
479 prompt "Cooperative memory management"
481 Select this option, if you want to enable the kernel interface
482 to reduce the memory size of the system. This is accomplished
483 by allocating pages of memory and put them "on hold". This only
484 makes sense for a system running under VM where the unused pages
485 will be reused by VM for other guest systems. The interface
486 allows an external monitor to balance memory of many systems.
487 Everybody who wants to run Linux under VM should select this
492 prompt "IUCV special message interface to cooperative memory management"
493 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
495 Select this option to enable the special message interface to
496 the cooperative memory management.
500 prompt "Linux - VM Monitor Stream, base infrastructure"
503 This provides a kernel interface for creating and updating z/VM APPLDATA
504 monitor records. The monitor records are updated at certain time
505 intervals, once the timer is started.
506 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
507 i.e. enables or disables monitoring on the Linux side.
508 A custom interval value (in seconds) can be written to
509 /proc/appldata/interval.
511 Defaults are 60 seconds interval and timer off.
512 The /proc entries can also be read from, showing the current settings.
516 prompt "Monitor memory management statistics"
517 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
519 This provides memory management related data to the Linux - VM Monitor
520 Stream, like paging/swapping rate, memory utilisation, etc.
521 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
522 APPLDATA monitor record, i.e. enables or disables monitoring this record
526 The /proc entry can also be read from, showing the current settings.
528 This can also be compiled as a module, which will be called
533 prompt "Monitor OS statistics"
534 depends on APPLDATA_BASE
536 This provides OS related data to the Linux - VM Monitor Stream, like
537 CPU utilisation, etc.
538 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
539 APPLDATA monitor record, i.e. enables or disables monitoring this record
543 This can also be compiled as a module, which will be called
546 config APPLDATA_NET_SUM
548 prompt "Monitor overall network statistics"
549 depends on APPLDATA_BASE && NET
551 This provides network related data to the Linux - VM Monitor Stream,
552 currently there is only a total sum of network I/O statistics, no
554 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
555 APPLDATA monitor record, i.e. enables or disables monitoring this record
559 This can also be compiled as a module, which will be called
562 source kernel/Kconfig.hz
566 prompt "s390 hypervisor file system support"
567 select SYS_HYPERVISOR
569 This is a virtual file system intended to provide accounting
570 information in an s390 hypervisor environment.
574 prompt "kexec system call"
576 kexec is a system call that implements the ability to shutdown your
577 current kernel, and to start another kernel. It is like a reboot
578 but is independent of hardware/microcode support.
582 prompt "zfcpdump support"
585 Select this option if you want to build an zfcpdump enabled kernel.
586 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
590 prompt "s390 guest support for KVM (EXPERIMENTAL)"
591 depends on 64BIT && EXPERIMENTAL
594 select VIRTIO_CONSOLE
596 Select this option if you want to run the kernel as a guest under
597 the KVM hypervisor. This will add detection for KVM as well as a
598 virtio transport. If KVM is detected, the virtio console will be
603 prompt "Enable seccomp to safely compute untrusted bytecode"
606 This kernel feature is useful for number crunching applications
607 that may need to compute untrusted bytecode during their
608 execution. By using pipes or other transports made available to
609 the process as file descriptors supporting the read/write
610 syscalls, it's possible to isolate those applications in
611 their own address space using seccomp. Once seccomp is
612 enabled via /proc/<pid>/seccomp, it cannot be disabled
613 and the task is only allowed to execute a few safe syscalls
614 defined by each seccomp mode.
620 menu "Power Management"
622 source "kernel/power/Kconfig"
634 source "drivers/Kconfig"
638 source "arch/s390/Kconfig.debug"
640 source "security/Kconfig"
642 source "crypto/Kconfig"
646 source "arch/s390/kvm/Kconfig"