1 # SPDX-License-Identifier: GPL-2.0
11 config LOCKDEP_SUPPORT
14 config STACKTRACE_SUPPORT
17 config RWSEM_GENERIC_SPINLOCK
20 config RWSEM_XCHGADD_ALGORITHM
23 config ARCH_HAS_ILOG2_U32
26 config ARCH_HAS_ILOG2_U64
29 config GENERIC_HWEIGHT
35 config GENERIC_BUG_RELATIVE_POINTERS
38 config ARCH_DMA_ADDR_T_64BIT
41 config GENERIC_LOCKBREAK
42 def_bool y if SMP && PREEMPT
47 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
63 config ARCH_SUPPORTS_UPROBES
68 select ARCH_BINFMT_ELF_STATE
69 select ARCH_HAS_DEVMEM_IS_ALLOWED
70 select ARCH_HAS_ELF_RANDOMIZE
71 select ARCH_HAS_FORTIFY_SOURCE
72 select ARCH_HAS_GCOV_PROFILE_ALL
73 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
75 select ARCH_HAS_SET_MEMORY
76 select ARCH_HAS_SG_CHAIN
77 select ARCH_HAS_STRICT_KERNEL_RWX
78 select ARCH_HAS_STRICT_MODULE_RWX
79 select ARCH_HAS_UBSAN_SANITIZE_ALL
80 select ARCH_HAVE_NMI_SAFE_CMPXCHG
81 select ARCH_INLINE_READ_LOCK
82 select ARCH_INLINE_READ_LOCK_BH
83 select ARCH_INLINE_READ_LOCK_IRQ
84 select ARCH_INLINE_READ_LOCK_IRQSAVE
85 select ARCH_INLINE_READ_TRYLOCK
86 select ARCH_INLINE_READ_UNLOCK
87 select ARCH_INLINE_READ_UNLOCK_BH
88 select ARCH_INLINE_READ_UNLOCK_IRQ
89 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
90 select ARCH_INLINE_SPIN_LOCK
91 select ARCH_INLINE_SPIN_LOCK_BH
92 select ARCH_INLINE_SPIN_LOCK_IRQ
93 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
94 select ARCH_INLINE_SPIN_TRYLOCK
95 select ARCH_INLINE_SPIN_TRYLOCK_BH
96 select ARCH_INLINE_SPIN_UNLOCK
97 select ARCH_INLINE_SPIN_UNLOCK_BH
98 select ARCH_INLINE_SPIN_UNLOCK_IRQ
99 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
100 select ARCH_INLINE_WRITE_LOCK
101 select ARCH_INLINE_WRITE_LOCK_BH
102 select ARCH_INLINE_WRITE_LOCK_IRQ
103 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
104 select ARCH_INLINE_WRITE_TRYLOCK
105 select ARCH_INLINE_WRITE_UNLOCK
106 select ARCH_INLINE_WRITE_UNLOCK_BH
107 select ARCH_INLINE_WRITE_UNLOCK_IRQ
108 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
109 select ARCH_SAVE_PAGE_KEYS if HIBERNATION
110 select ARCH_SUPPORTS_ATOMIC_RMW
111 select ARCH_SUPPORTS_NUMA_BALANCING
112 select ARCH_USE_BUILTIN_BSWAP
113 select ARCH_USE_CMPXCHG_LOCKREF
114 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
115 select ARCH_WANTS_PROT_NUMA_PROT_NONE
116 select ARCH_WANTS_UBSAN_NO_NULL
117 select ARCH_WANT_IPC_PARSE_VERSION
118 select BUILDTIME_EXTABLE_SORT
119 select CLONE_BACKWARDS2
120 select DYNAMIC_FTRACE if FUNCTION_TRACER
121 select GENERIC_CLOCKEVENTS
122 select GENERIC_CPU_AUTOPROBE
123 select GENERIC_CPU_DEVICES if !SMP
124 select GENERIC_FIND_FIRST_BIT
125 select GENERIC_SMP_IDLE_THREAD
126 select GENERIC_TIME_VSYSCALL
127 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
128 select HAVE_ARCH_AUDITSYSCALL
129 select HAVE_ARCH_JUMP_LABEL
130 select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
131 select HAVE_ARCH_SECCOMP_FILTER
132 select HAVE_ARCH_SOFT_DIRTY
133 select HAVE_ARCH_TRACEHOOK
134 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
135 select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
136 select HAVE_CMPXCHG_DOUBLE
137 select HAVE_CMPXCHG_LOCAL
138 select HAVE_COPY_THREAD_TLS
139 select HAVE_DEBUG_KMEMLEAK
140 select HAVE_DMA_API_DEBUG
141 select HAVE_DMA_CONTIGUOUS
142 select DMA_DIRECT_OPS
143 select HAVE_DYNAMIC_FTRACE
144 select HAVE_DYNAMIC_FTRACE_WITH_REGS
145 select HAVE_EFFICIENT_UNALIGNED_ACCESS
146 select HAVE_FTRACE_MCOUNT_RECORD
147 select HAVE_FUNCTION_GRAPH_TRACER
148 select HAVE_FUNCTION_TRACER
149 select HAVE_FUTEX_CMPXCHG if FUTEX
150 select HAVE_GCC_PLUGINS
151 select HAVE_KERNEL_BZIP2
152 select HAVE_KERNEL_GZIP
153 select HAVE_KERNEL_LZ4
154 select HAVE_KERNEL_LZMA
155 select HAVE_KERNEL_LZO
156 select HAVE_KERNEL_XZ
158 select HAVE_KRETPROBES
160 select HAVE_LIVEPATCH
161 select HAVE_PERF_REGS
162 select HAVE_PERF_USER_STACK_DUMP
164 select HAVE_MEMBLOCK_NODE_MAP
165 select HAVE_MEMBLOCK_PHYS_MAP
166 select HAVE_MOD_ARCH_SPECIFIC
168 select HAVE_PERF_EVENTS
169 select HAVE_REGS_AND_STACK_ACCESS_API
170 select HAVE_SYSCALL_TRACEPOINTS
171 select HAVE_VIRT_CPU_ACCOUNTING
172 select MODULES_USE_ELF_RELA
175 select OLD_SIGSUSPEND3
177 select SYSCTL_EXCEPTION_TRACE
178 select THREAD_INFO_IN_TASK
180 select VIRT_CPU_ACCOUNTING
181 select ARCH_HAS_SCALED_CPUTIME
186 config SCHED_OMIT_FRAME_POINTER
189 config PGTABLE_LEVELS
193 source "init/Kconfig"
195 source "kernel/Kconfig.freezer"
197 source "kernel/livepatch/Kconfig"
199 menu "Processor type and features"
201 config HAVE_MARCH_Z900_FEATURES
204 config HAVE_MARCH_Z990_FEATURES
206 select HAVE_MARCH_Z900_FEATURES
208 config HAVE_MARCH_Z9_109_FEATURES
210 select HAVE_MARCH_Z990_FEATURES
212 config HAVE_MARCH_Z10_FEATURES
214 select HAVE_MARCH_Z9_109_FEATURES
216 config HAVE_MARCH_Z196_FEATURES
218 select HAVE_MARCH_Z10_FEATURES
220 config HAVE_MARCH_ZEC12_FEATURES
222 select HAVE_MARCH_Z196_FEATURES
224 config HAVE_MARCH_Z13_FEATURES
226 select HAVE_MARCH_ZEC12_FEATURES
228 config HAVE_MARCH_Z14_FEATURES
230 select HAVE_MARCH_Z13_FEATURES
233 prompt "Processor type"
237 bool "IBM zSeries model z800 and z900"
238 select HAVE_MARCH_Z900_FEATURES
240 Select this to enable optimizations for model z800/z900 (2064 and
241 2066 series). This will enable some optimizations that are not
242 available on older ESA/390 (31 Bit) only CPUs.
245 bool "IBM zSeries model z890 and z990"
246 select HAVE_MARCH_Z990_FEATURES
248 Select this to enable optimizations for model z890/z990 (2084 and
249 2086 series). The kernel will be slightly faster but will not work
254 select HAVE_MARCH_Z9_109_FEATURES
256 Select this to enable optimizations for IBM System z9 (2094 and
257 2096 series). The kernel will be slightly faster but will not work
261 bool "IBM System z10"
262 select HAVE_MARCH_Z10_FEATURES
264 Select this to enable optimizations for IBM System z10 (2097 and
265 2098 series). The kernel will be slightly faster but will not work
269 bool "IBM zEnterprise 114 and 196"
270 select HAVE_MARCH_Z196_FEATURES
272 Select this to enable optimizations for IBM zEnterprise 114 and 196
273 (2818 and 2817 series). The kernel will be slightly faster but will
274 not work on older machines.
277 bool "IBM zBC12 and zEC12"
278 select HAVE_MARCH_ZEC12_FEATURES
280 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
281 2827 series). The kernel will be slightly faster but will not work on
285 bool "IBM z13s and z13"
286 select HAVE_MARCH_Z13_FEATURES
288 Select this to enable optimizations for IBM z13s and z13 (2965 and
289 2964 series). The kernel will be slightly faster but will not work on
294 select HAVE_MARCH_Z14_FEATURES
296 Select this to enable optimizations for IBM z14 (3906 series).
297 The kernel will be slightly faster but will not work on older
302 config MARCH_Z900_TUNE
303 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
305 config MARCH_Z990_TUNE
306 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
308 config MARCH_Z9_109_TUNE
309 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
311 config MARCH_Z10_TUNE
312 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
314 config MARCH_Z196_TUNE
315 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
317 config MARCH_ZEC12_TUNE
318 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
320 config MARCH_Z13_TUNE
321 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
323 config MARCH_Z14_TUNE
324 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
327 prompt "Tune code generation"
330 Cause the compiler to tune (-mtune) the generated code for a machine.
331 This will make the code run faster on the selected machine but
332 somewhat slower on other machines.
333 This option only changes how the compiler emits instructions, not the
334 selection of instructions itself, so the resulting kernel will run on
340 Tune the generated code for the target processor for which the kernel
344 bool "IBM zSeries model z800 and z900"
347 bool "IBM zSeries model z890 and z990"
353 bool "IBM System z10"
356 bool "IBM zEnterprise 114 and 196"
359 bool "IBM zBC12 and zEC12"
374 prompt "Kernel support for 31 bit emulation"
375 select COMPAT_BINFMT_ELF if BINFMT_ELF
376 select ARCH_WANT_OLD_COMPAT_IPC
377 select COMPAT_OLD_SIGACTION
380 Select this option if you want to enable your system kernel to
381 handle system-calls from ELF binaries for 31 bit ESA. This option
382 (and some other stuff like libraries and such) is needed for
383 executing 31 bit applications. It is safe to say "Y".
385 config SYSVIPC_COMPAT
386 def_bool y if COMPAT && SYSVIPC
390 prompt "Symmetric multi-processing support"
392 This enables support for systems with more than one CPU. If you have
393 a system with only one CPU, like most personal computers, say N. If
394 you have a system with more than one CPU, say Y.
396 If you say N here, the kernel will run on uni- and multiprocessor
397 machines, but will use only one CPU of a multiprocessor machine. If
398 you say Y here, the kernel will run on many, but not all,
399 uniprocessor machines. On a uniprocessor machine, the kernel
400 will run faster if you say N here.
402 See also the SMP-HOWTO available at
403 <http://www.tldp.org/docs.html#howto>.
405 Even if you don't know what to do here, say Y.
408 int "Maximum number of CPUs (2-512)"
413 This allows you to specify the maximum number of CPUs which this
414 kernel will support. The maximum supported value is 512 and the
415 minimum value which makes sense is 2.
417 This is purely to save memory - each supported CPU adds
418 approximately sixteen kilobytes to the kernel image.
422 prompt "Support for hot-pluggable CPUs"
425 Say Y here to be able to turn CPUs off and on. CPUs
426 can be controlled through /sys/devices/system/cpu/cpu#.
427 Say N if you want to disable CPU hotplug.
429 # Some NUMA nodes have memory ranges that span
430 # other nodes. Even though a pfn is valid and
431 # between a node's start and end pfns, it may not
432 # reside on that node. See memmap_init_zone()
433 # for details. <- They meant memory holes!
434 config NODES_SPAN_OTHER_NODES
439 depends on SMP && SCHED_TOPOLOGY
444 This option adds NUMA support to the kernel.
446 An operation mode can be selected by appending
447 numa=<method> to the kernel command line.
449 The default behaviour is identical to appending numa=plain to
450 the command line. This will create just one node with all
451 available memory and all CPUs in it.
454 int "Maximum NUMA nodes (as a power of 2)"
459 Specify the maximum number of NUMA nodes available on the target
460 system. Increases memory reserved to accommodate various tables.
462 menu "Select NUMA modes"
466 bool "NUMA emulation"
469 Numa emulation mode will split the available system memory into
470 equal chunks which then are distributed over the configured number
471 of nodes in a round-robin manner.
473 The number of fake nodes is limited by the number of available memory
474 chunks (i.e. memory size / fake size) and the number of supported
477 The CPUs are assigned to the nodes in a way that partially respects
478 the original machine topology (if supported by the machine).
479 Fair distribution of the CPUs is not guaranteed.
482 hex "NUMA emulation memory chunk size"
484 range 0x400000 0x100000000
487 Select the default size by which the memory is chopped and then
488 assigned to emulated NUMA nodes.
490 This can be overridden by specifying
494 on the kernel command line where also suffixes K, M, G, and T are
511 config SCHED_TOPOLOGY
513 prompt "Topology scheduler support"
520 Topology scheduler support improves the CPU scheduler's decision
521 making when dealing with machines that have multi-threading,
522 multiple cores or multiple books.
524 source kernel/Kconfig.preempt
526 source kernel/Kconfig.hz
530 prompt "s390 architectural random number generation API"
532 Enable the s390 architectural random number generation API
533 to provide random data for all consumers within the Linux
536 When enabled the arch_random_* functions declared in linux/random.h
537 are implemented. The implementation is based on the s390 CPACF
538 instruction subfunction TRNG which provides a real true random
547 config ARCH_SPARSEMEM_ENABLE
549 select SPARSEMEM_VMEMMAP_ENABLE
550 select SPARSEMEM_VMEMMAP
552 config ARCH_SPARSEMEM_DEFAULT
555 config ARCH_SELECT_MEMORY_MODEL
558 config ARCH_ENABLE_MEMORY_HOTPLUG
559 def_bool y if SPARSEMEM
561 config ARCH_ENABLE_MEMORY_HOTREMOVE
564 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
567 config FORCE_MAX_ZONEORDER
573 config MAX_PHYSMEM_BITS
574 int "Maximum size of supported physical memory in bits (42-53)"
578 This option specifies the maximum supported size of physical memory
579 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
580 Increasing the number of bits also increases the kernel image size.
581 By default 46 bits (64TB) are supported.
585 prompt "Pack kernel stack"
587 This option enables the compiler option -mkernel-backchain if it
588 is available. If the option is available the compiler supports
589 the new stack layout which dramatically reduces the minimum stack
590 frame size. With an old compiler a non-leaf function needs a
591 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
592 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
593 and 24 byte on 64 bit.
595 Say Y if you are unsure.
599 prompt "Detect kernel stack overflow"
601 This option enables the compiler option -mstack-guard and
602 -mstack-size if they are available. If the compiler supports them
603 it will emit additional code to each function prolog to trigger
604 an illegal operation if the kernel stack is about to overflow.
606 Say N if you are unsure.
609 int "Size of the guard area (128-1024)"
611 depends on CHECK_STACK
614 This allows you to specify the size of the guard area at the lower
615 end of the kernel stack. If the kernel stack points into the guard
616 area on function entry an illegal operation is triggered. The size
617 needs to be a power of 2. Please keep in mind that the size of an
618 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
619 The minimum size for the stack guard should be 256 for 31 bit and
622 config WARN_DYNAMIC_STACK
624 prompt "Emit compiler warnings for function with dynamic stack usage"
626 This option enables the compiler option -mwarn-dynamicstack. If the
627 compiler supports this options generates warnings for functions
628 that dynamically allocate stack space using alloca.
630 Say N if you are unsure.
638 prompt "QDIO support"
640 This driver provides the Queued Direct I/O base support for
643 To compile this driver as a module, choose M here: the
644 module will be called qdio.
657 config PCI_NR_FUNCTIONS
658 int "Maximum number of PCI functions (1-4096)"
662 This allows you to specify the maximum number of PCI functions which
663 this kernel will support.
665 source "drivers/pci/Kconfig"
678 config NEED_SG_DMA_LENGTH
681 config NEED_DMA_MAP_STATE
686 prompt "Support for CHSC subchannels"
688 This driver allows usage of CHSC subchannels. A CHSC subchannel
689 is usually present on LPAR only.
690 The driver creates a device /dev/chsc, which may be used to
691 obtain I/O configuration information about the machine and
692 to issue asynchronous chsc commands (DANGEROUS).
693 You will usually only want to use this interface on a special
694 LPAR designated for system management.
696 To compile this driver as a module, choose M here: the
697 module will be called chsc_sch.
703 prompt "SCM bus driver"
705 Bus driver for Storage Class Memory.
709 prompt "Support for EADM subchannels"
712 This driver allows usage of EADM subchannels. EADM subchannels act
713 as a communication vehicle for SCM increments.
715 To compile this driver as a module, choose M here: the
716 module will be called eadm_sch.
720 prompt "Support for VFIO-CCW subchannels"
721 depends on S390_CCW_IOMMU && VFIO_MDEV
723 This driver allows usage of I/O subchannels via VFIO-CCW.
725 To compile this driver as a module, choose M here: the
726 module will be called vfio_ccw.
733 bool "kernel crash dumps"
737 Generate crash dump after being started by kexec.
738 Crash dump kernels are loaded in the main kernel with kexec-tools
739 into a specially reserved region and then later executed after
740 a crash by kdump/kexec.
741 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
742 This option also enables s390 zfcpdump.
743 See also <file:Documentation/s390/zfcpdump.txt>
747 menu "Executable file formats / Emulations"
749 source "fs/Kconfig.binfmt"
753 prompt "Enable seccomp to safely compute untrusted bytecode"
756 This kernel feature is useful for number crunching applications
757 that may need to compute untrusted bytecode during their
758 execution. By using pipes or other transports made available to
759 the process as file descriptors supporting the read/write
760 syscalls, it's possible to isolate those applications in
761 their own address space using seccomp. Once seccomp is
762 enabled via /proc/<pid>/seccomp, it cannot be disabled
763 and the task is only allowed to execute a few safe syscalls
764 defined by each seccomp mode.
770 menu "Power Management"
772 config ARCH_HIBERNATION_POSSIBLE
775 source "kernel/power/Kconfig"
787 source "drivers/Kconfig"
791 source "arch/s390/Kconfig.debug"
793 source "security/Kconfig"
795 source "crypto/Kconfig"
799 menu "Virtualization"
803 prompt "Pseudo page fault support"
805 Select this option, if you want to use PFAULT pseudo page fault
806 handling under VM. If running native or in LPAR, this option
807 has no effect. If your VM does not support PFAULT, PAGEEX
808 pseudo page fault handling will be used.
809 Note that VM 4.2 supports PFAULT but has a bug in its
810 implementation that causes some problems.
811 Everybody who wants to run Linux under VM != VM4.2 should select
816 prompt "Cooperative memory management"
818 Select this option, if you want to enable the kernel interface
819 to reduce the memory size of the system. This is accomplished
820 by allocating pages of memory and put them "on hold". This only
821 makes sense for a system running under VM where the unused pages
822 will be reused by VM for other guest systems. The interface
823 allows an external monitor to balance memory of many systems.
824 Everybody who wants to run Linux under VM should select this
829 prompt "IUCV special message interface to cooperative memory management"
830 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
832 Select this option to enable the special message interface to
833 the cooperative memory management.
837 prompt "Linux - VM Monitor Stream, base infrastructure"
840 This provides a kernel interface for creating and updating z/VM APPLDATA
841 monitor records. The monitor records are updated at certain time
842 intervals, once the timer is started.
843 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
844 i.e. enables or disables monitoring on the Linux side.
845 A custom interval value (in seconds) can be written to
846 /proc/appldata/interval.
848 Defaults are 60 seconds interval and timer off.
849 The /proc entries can also be read from, showing the current settings.
853 prompt "Monitor memory management statistics"
854 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
856 This provides memory management related data to the Linux - VM Monitor
857 Stream, like paging/swapping rate, memory utilisation, etc.
858 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
859 APPLDATA monitor record, i.e. enables or disables monitoring this record
863 The /proc entry can also be read from, showing the current settings.
865 This can also be compiled as a module, which will be called
870 prompt "Monitor OS statistics"
871 depends on APPLDATA_BASE
873 This provides OS related data to the Linux - VM Monitor Stream, like
874 CPU utilisation, etc.
875 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
876 APPLDATA monitor record, i.e. enables or disables monitoring this record
880 This can also be compiled as a module, which will be called
883 config APPLDATA_NET_SUM
885 prompt "Monitor overall network statistics"
886 depends on APPLDATA_BASE && NET
888 This provides network related data to the Linux - VM Monitor Stream,
889 currently there is only a total sum of network I/O statistics, no
891 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
892 APPLDATA monitor record, i.e. enables or disables monitoring this record
896 This can also be compiled as a module, which will be called
901 prompt "s390 hypervisor file system support"
902 select SYS_HYPERVISOR
904 This is a virtual file system intended to provide accounting
905 information in an s390 hypervisor environment.
907 source "arch/s390/kvm/Kconfig"
911 prompt "s390 support for virtio devices"
913 select VIRTUALIZATION
915 select VIRTIO_CONSOLE
917 Enabling this option adds support for virtio based paravirtual device
920 Select this option if you want to run the kernel as a guest under