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 ARCH_SAVE_PAGE_KEYS if HIBERNATION
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
122 select ARCH_SUPPORTS_ATOMIC_RMW
124 config SCHED_OMIT_FRAME_POINTER
127 source "init/Kconfig"
129 source "kernel/Kconfig.freezer"
133 comment "Processor type and features"
135 source "kernel/time/Kconfig"
139 prompt "64 bit kernel"
141 Select this option if you have an IBM z/Architecture machine
142 and want to use the 64 bit addressing mode.
152 prompt "Symmetric multi-processing support"
154 This enables support for systems with more than one CPU. If you have
155 a system with only one CPU, like most personal computers, say N. If
156 you have a system with more than one CPU, say Y.
158 If you say N here, the kernel will run on single and multiprocessor
159 machines, but will use only one CPU of a multiprocessor machine. If
160 you say Y here, the kernel will run on many, but not all,
161 singleprocessor machines. On a singleprocessor machine, the kernel
162 will run faster if you say N here.
164 See also the SMP-HOWTO available at
165 <http://www.tldp.org/docs.html#howto>.
167 Even if you don't know what to do here, say Y.
170 int "Maximum number of CPUs (2-64)"
173 default "32" if !64BIT
174 default "64" if 64BIT
176 This allows you to specify the maximum number of CPUs which this
177 kernel will support. The maximum supported value is 64 and the
178 minimum value which makes sense is 2.
180 This is purely to save memory - each supported CPU adds
181 approximately sixteen kilobytes to the kernel image.
185 prompt "Support for hot-pluggable CPUs"
189 Say Y here to be able to turn CPUs off and on. CPUs
190 can be controlled through /sys/devices/system/cpu/cpu#.
191 Say N if you want to disable CPU hotplug.
195 prompt "Multi-core scheduler support"
198 Multi-core scheduler support improves the CPU scheduler's decision
199 making when dealing with multi-core CPU chips at a cost of slightly
200 increased overhead in some places.
204 prompt "Book scheduler support"
205 depends on SMP && SCHED_MC
207 Book scheduler support improves the CPU scheduler's decision making
208 when dealing with machines that have several books.
212 prompt "IEEE FPU emulation"
215 This option is required for IEEE compliant floating point arithmetic
216 on older ESA/390 machines. Say Y unless you know your machine doesn't
221 prompt "Kernel support for 31 bit emulation"
223 select COMPAT_BINFMT_ELF
225 Select this option if you want to enable your system kernel to
226 handle system-calls from ELF binaries for 31 bit ESA. This option
227 (and some other stuff like libraries and such) is needed for
228 executing 31 bit applications. It is safe to say "Y".
230 config SYSVIPC_COMPAT
231 def_bool y if COMPAT && SYSVIPC
234 def_bool y if COMPAT && KEYS
239 comment "Code generation options"
242 prompt "Processor type"
246 bool "System/390 model G5 and G6"
249 Select this to build a 31 bit kernel that works
250 on all ESA/390 and z/Architecture machines.
253 bool "IBM zSeries model z800 and z900"
255 Select this to enable optimizations for model z800/z900 (2064 and
256 2066 series). This will enable some optimizations that are not
257 available on older ESA/390 (31 Bit) only CPUs.
260 bool "IBM zSeries model z890 and z990"
262 Select this to enable optimizations for model z890/z990 (2084 and
263 2086 series). The kernel will be slightly faster but will not work
269 Select this to enable optimizations for IBM System z9 (2094 and
270 2096 series). The kernel will be slightly faster but will not work
274 bool "IBM System z10"
276 Select this to enable optimizations for IBM System z10 (2097 and
277 2098 series). The kernel will be slightly faster but will not work
281 bool "IBM zEnterprise 114 and 196"
283 Select this to enable optimizations for IBM zEnterprise 114 and 196
284 (2818 and 2817 series). The kernel will be slightly faster but will
285 not work on older machines.
291 prompt "Pack kernel stack"
293 This option enables the compiler option -mkernel-backchain if it
294 is available. If the option is available the compiler supports
295 the new stack layout which dramatically reduces the minimum stack
296 frame size. With an old compiler a non-leaf function needs a
297 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
298 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
299 and 24 byte on 64 bit.
301 Say Y if you are unsure.
305 prompt "Use 8kb for kernel stack instead of 16kb"
306 depends on PACK_STACK && 64BIT && !LOCKDEP
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.
314 Say N if you are unsure.
318 prompt "Detect kernel stack overflow"
320 This option enables the compiler option -mstack-guard and
321 -mstack-size if they are available. If the compiler supports them
322 it will emit additional code to each function prolog to trigger
323 an illegal operation if the kernel stack is about to overflow.
325 Say N if you are unsure.
328 int "Size of the guard area (128-1024)"
330 depends on CHECK_STACK
333 This allows you to specify the size of the guard area at the lower
334 end of the kernel stack. If the kernel stack points into the guard
335 area on function entry an illegal operation is triggered. The size
336 needs to be a power of 2. Please keep in mind that the size of an
337 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
338 The minimum size for the stack guard should be 256 for 31 bit and
341 config WARN_DYNAMIC_STACK
343 prompt "Emit compiler warnings for function with dynamic stack usage"
345 This option enables the compiler option -mwarn-dynamicstack. If the
346 compiler supports this options generates warnings for functions
347 that dynamically allocate stack space using alloca.
349 Say N if you are unsure.
351 config ARCH_POPULATES_NODE_MAP
354 comment "Kernel preemption"
356 source "kernel/Kconfig.preempt"
358 config ARCH_SPARSEMEM_ENABLE
360 select SPARSEMEM_VMEMMAP_ENABLE
361 select SPARSEMEM_VMEMMAP
362 select SPARSEMEM_STATIC if !64BIT
364 config ARCH_SPARSEMEM_DEFAULT
367 config ARCH_SELECT_MEMORY_MODEL
370 config ARCH_ENABLE_MEMORY_HOTPLUG
371 def_bool y if SPARSEMEM
373 config ARCH_ENABLE_MEMORY_HOTREMOVE
376 config ARCH_HIBERNATION_POSSIBLE
381 comment "I/O subsystem configuration"
385 prompt "QDIO support"
387 This driver provides the Queued Direct I/O base support for
390 To compile this driver as a module, choose M here: the
391 module will be called qdio.
397 prompt "Support for CHSC subchannels"
399 This driver allows usage of CHSC subchannels. A CHSC subchannel
400 is usually present on LPAR only.
401 The driver creates a device /dev/chsc, which may be used to
402 obtain I/O configuration information about the machine and
403 to issue asynchronous chsc commands (DANGEROUS).
404 You will usually only want to use this interface on a special
405 LPAR designated for system management.
407 To compile this driver as a module, choose M here: the
408 module will be called chsc_sch.
416 prompt "Builtin IPL record support"
418 If you want to use the produced kernel to IPL directly from a
419 device, you have to merge a bootsector specific to the device
420 into the first bytes of the kernel. You will have to select the
424 prompt "IPL method generated into head.S"
428 Select "tape" if you want to IPL the image from a Tape.
430 Select "vm_reader" if you are running under VM/ESA and want
431 to IPL the image from the emulated card reader.
441 source "fs/Kconfig.binfmt"
443 config FORCE_MAX_ZONEORDER
449 prompt "Pseudo page fault support"
451 Select this option, if you want to use PFAULT pseudo page fault
452 handling under VM. If running native or in LPAR, this option
453 has no effect. If your VM does not support PFAULT, PAGEEX
454 pseudo page fault handling will be used.
455 Note that VM 4.2 supports PFAULT but has a bug in its
456 implementation that causes some problems.
457 Everybody who wants to run Linux under VM != VM4.2 should select
462 prompt "VM shared kernel support"
464 Select this option, if you want to share the text segment of the
465 Linux kernel between different VM guests. This reduces memory
466 usage with lots of guests but greatly increases kernel size.
467 Also if a kernel was IPL'ed from a shared segment the kexec system
469 You should only select this option if you know what you are
470 doing and want to exploit this feature.
474 prompt "Cooperative memory management"
476 Select this option, if you want to enable the kernel interface
477 to reduce the memory size of the system. This is accomplished
478 by allocating pages of memory and put them "on hold". This only
479 makes sense for a system running under VM where the unused pages
480 will be reused by VM for other guest systems. The interface
481 allows an external monitor to balance memory of many systems.
482 Everybody who wants to run Linux under VM should select this
487 prompt "IUCV special message interface to cooperative memory management"
488 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
490 Select this option to enable the special message interface to
491 the cooperative memory management.
495 prompt "Linux - VM Monitor Stream, base infrastructure"
498 This provides a kernel interface for creating and updating z/VM APPLDATA
499 monitor records. The monitor records are updated at certain time
500 intervals, once the timer is started.
501 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
502 i.e. enables or disables monitoring on the Linux side.
503 A custom interval value (in seconds) can be written to
504 /proc/appldata/interval.
506 Defaults are 60 seconds interval and timer off.
507 The /proc entries can also be read from, showing the current settings.
511 prompt "Monitor memory management statistics"
512 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
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
521 The /proc entry can also be read from, showing the current settings.
523 This can also be compiled as a module, which will be called
528 prompt "Monitor OS statistics"
529 depends on APPLDATA_BASE
531 This provides OS related data to the Linux - VM Monitor Stream, like
532 CPU utilisation, etc.
533 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
534 APPLDATA monitor record, i.e. enables or disables monitoring this record
538 This can also be compiled as a module, which will be called
541 config APPLDATA_NET_SUM
543 prompt "Monitor overall network statistics"
544 depends on APPLDATA_BASE && NET
546 This provides network related data to the Linux - VM Monitor Stream,
547 currently there is only a total sum of network I/O statistics, no
549 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
550 APPLDATA monitor record, i.e. enables or disables monitoring this record
554 This can also be compiled as a module, which will be called
557 source kernel/Kconfig.hz
561 prompt "s390 hypervisor file system support"
562 select SYS_HYPERVISOR
564 This is a virtual file system intended to provide accounting
565 information in an s390 hypervisor environment.
569 prompt "kexec system call"
571 kexec is a system call that implements the ability to shutdown your
572 current kernel, and to start another kernel. It is like a reboot
573 but is independent of hardware/microcode support.
576 bool "kernel crash dumps"
580 Generate crash dump after being started by kexec.
581 Crash dump kernels are loaded in the main kernel with kexec-tools
582 into a specially reserved region and then later executed after
583 a crash by kdump/kexec.
584 For more details see Documentation/kdump/kdump.txt
588 prompt "zfcpdump support"
591 Select this option if you want to build an zfcpdump enabled kernel.
592 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
596 prompt "s390 guest support for KVM (EXPERIMENTAL)"
597 depends on 64BIT && EXPERIMENTAL
598 select VIRTUALIZATION
601 select VIRTIO_CONSOLE
603 Select this option if you want to run the kernel as a guest under
604 the KVM hypervisor. This will add detection for KVM as well as a
605 virtio transport. If KVM is detected, the virtio console will be
610 prompt "Enable seccomp to safely compute untrusted bytecode"
613 This kernel feature is useful for number crunching applications
614 that may need to compute untrusted bytecode during their
615 execution. By using pipes or other transports made available to
616 the process as file descriptors supporting the read/write
617 syscalls, it's possible to isolate those applications in
618 their own address space using seccomp. Once seccomp is
619 enabled via /proc/<pid>/seccomp, it cannot be disabled
620 and the task is only allowed to execute a few safe syscalls
621 defined by each seccomp mode.
627 menu "Power Management"
629 source "kernel/power/Kconfig"
641 source "drivers/Kconfig"
645 source "arch/s390/Kconfig.debug"
647 source "security/Kconfig"
649 source "crypto/Kconfig"
653 source "arch/s390/kvm/Kconfig"