1 # SPDX-License-Identifier: GPL-2.0
11 config LOCKDEP_SUPPORT
14 config STACKTRACE_SUPPORT
17 config ARCH_HAS_ILOG2_U32
20 config ARCH_HAS_ILOG2_U64
23 config GENERIC_HWEIGHT
29 config GENERIC_BUG_RELATIVE_POINTERS
32 config GENERIC_LOCKBREAK
38 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
50 config ARCH_SUPPORTS_UPROBES
53 config KASAN_SHADOW_OFFSET
56 default 0x18000000000000 if KASAN_S390_4_LEVEL_PAGING
61 select ARCH_BINFMT_ELF_STATE
62 select ARCH_HAS_DEVMEM_IS_ALLOWED
63 select ARCH_HAS_ELF_RANDOMIZE
64 select ARCH_HAS_FORTIFY_SOURCE
65 select ARCH_HAS_GCOV_PROFILE_ALL
66 select ARCH_HAS_GIGANTIC_PAGE
68 select ARCH_HAS_MEM_ENCRYPT
69 select ARCH_HAS_PTE_SPECIAL
70 select ARCH_HAS_SET_MEMORY
71 select ARCH_HAS_STRICT_KERNEL_RWX
72 select ARCH_HAS_STRICT_MODULE_RWX
73 select ARCH_HAS_SYSCALL_WRAPPER
74 select ARCH_HAS_UBSAN_SANITIZE_ALL
75 select ARCH_HAVE_NMI_SAFE_CMPXCHG
76 select ARCH_INLINE_READ_LOCK
77 select ARCH_INLINE_READ_LOCK_BH
78 select ARCH_INLINE_READ_LOCK_IRQ
79 select ARCH_INLINE_READ_LOCK_IRQSAVE
80 select ARCH_INLINE_READ_TRYLOCK
81 select ARCH_INLINE_READ_UNLOCK
82 select ARCH_INLINE_READ_UNLOCK_BH
83 select ARCH_INLINE_READ_UNLOCK_IRQ
84 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
85 select ARCH_INLINE_SPIN_LOCK
86 select ARCH_INLINE_SPIN_LOCK_BH
87 select ARCH_INLINE_SPIN_LOCK_IRQ
88 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
89 select ARCH_INLINE_SPIN_TRYLOCK
90 select ARCH_INLINE_SPIN_TRYLOCK_BH
91 select ARCH_INLINE_SPIN_UNLOCK
92 select ARCH_INLINE_SPIN_UNLOCK_BH
93 select ARCH_INLINE_SPIN_UNLOCK_IRQ
94 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
95 select ARCH_INLINE_WRITE_LOCK
96 select ARCH_INLINE_WRITE_LOCK_BH
97 select ARCH_INLINE_WRITE_LOCK_IRQ
98 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
99 select ARCH_INLINE_WRITE_TRYLOCK
100 select ARCH_INLINE_WRITE_UNLOCK
101 select ARCH_INLINE_WRITE_UNLOCK_BH
102 select ARCH_INLINE_WRITE_UNLOCK_IRQ
103 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
104 select ARCH_KEEP_MEMBLOCK
105 select ARCH_SAVE_PAGE_KEYS if HIBERNATION
106 select ARCH_STACKWALK
107 select ARCH_SUPPORTS_ATOMIC_RMW
108 select ARCH_SUPPORTS_NUMA_BALANCING
109 select ARCH_USE_BUILTIN_BSWAP
110 select ARCH_USE_CMPXCHG_LOCKREF
111 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
112 select ARCH_WANT_IPC_PARSE_VERSION
113 select BUILDTIME_EXTABLE_SORT
114 select CLONE_BACKWARDS2
115 select DYNAMIC_FTRACE if FUNCTION_TRACER
116 select GENERIC_CLOCKEVENTS
117 select GENERIC_CPU_AUTOPROBE
118 select GENERIC_CPU_VULNERABILITIES
119 select GENERIC_FIND_FIRST_BIT
120 select GENERIC_SMP_IDLE_THREAD
121 select GENERIC_TIME_VSYSCALL
122 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
123 select HAVE_ARCH_AUDITSYSCALL
124 select HAVE_ARCH_JUMP_LABEL
125 select HAVE_ARCH_JUMP_LABEL_RELATIVE
126 select HAVE_ARCH_KASAN
127 select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
128 select HAVE_ARCH_SECCOMP_FILTER
129 select HAVE_ARCH_SOFT_DIRTY
130 select HAVE_ARCH_TRACEHOOK
131 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
132 select HAVE_ARCH_VMAP_STACK
133 select HAVE_ASM_MODVERSIONS
134 select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
135 select HAVE_CMPXCHG_DOUBLE
136 select HAVE_CMPXCHG_LOCAL
137 select HAVE_COPY_THREAD_TLS
138 select HAVE_DEBUG_KMEMLEAK
139 select HAVE_DMA_CONTIGUOUS
140 select HAVE_DYNAMIC_FTRACE
141 select HAVE_DYNAMIC_FTRACE_WITH_REGS
143 select HAVE_EFFICIENT_UNALIGNED_ACCESS
145 select HAVE_FTRACE_MCOUNT_RECORD
146 select HAVE_FUNCTION_GRAPH_TRACER
147 select HAVE_FUNCTION_TRACER
148 select HAVE_FUTEX_CMPXCHG if FUTEX
149 select HAVE_GCC_PLUGINS
150 select HAVE_KERNEL_BZIP2
151 select HAVE_KERNEL_GZIP
152 select HAVE_KERNEL_LZ4
153 select HAVE_KERNEL_LZMA
154 select HAVE_KERNEL_LZO
155 select HAVE_KERNEL_UNCOMPRESSED
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
163 select HAVE_MEMBLOCK_NODE_MAP
164 select HAVE_MEMBLOCK_PHYS_MAP
165 select HAVE_MMU_GATHER_NO_GATHER
166 select HAVE_MOD_ARCH_SPECIFIC
167 select HAVE_NOP_MCOUNT
170 select HAVE_PERF_EVENTS
171 select HAVE_RCU_TABLE_FREE
172 select HAVE_REGS_AND_STACK_ACCESS_API
173 select HAVE_RELIABLE_STACKTRACE
175 select HAVE_SYSCALL_TRACEPOINTS
176 select HAVE_VIRT_CPU_ACCOUNTING
177 select IOMMU_HELPER if PCI
178 select IOMMU_SUPPORT if PCI
179 select MODULES_USE_ELF_RELA
180 select NEED_DMA_MAP_STATE if PCI
181 select NEED_SG_DMA_LENGTH if PCI
183 select OLD_SIGSUSPEND3
184 select PCI_DOMAINS if PCI
185 select PCI_MSI if PCI
187 select SYSCTL_EXCEPTION_TRACE
188 select THREAD_INFO_IN_TASK
190 select VIRT_CPU_ACCOUNTING
191 select ARCH_HAS_SCALED_CPUTIME
193 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
195 select GENERIC_ALLOCATOR
198 config SCHED_OMIT_FRAME_POINTER
201 config PGTABLE_LEVELS
205 source "kernel/livepatch/Kconfig"
207 menu "Processor type and features"
209 config HAVE_MARCH_Z900_FEATURES
212 config HAVE_MARCH_Z990_FEATURES
214 select HAVE_MARCH_Z900_FEATURES
216 config HAVE_MARCH_Z9_109_FEATURES
218 select HAVE_MARCH_Z990_FEATURES
220 config HAVE_MARCH_Z10_FEATURES
222 select HAVE_MARCH_Z9_109_FEATURES
224 config HAVE_MARCH_Z196_FEATURES
226 select HAVE_MARCH_Z10_FEATURES
228 config HAVE_MARCH_ZEC12_FEATURES
230 select HAVE_MARCH_Z196_FEATURES
232 config HAVE_MARCH_Z13_FEATURES
234 select HAVE_MARCH_ZEC12_FEATURES
236 config HAVE_MARCH_Z14_FEATURES
238 select HAVE_MARCH_Z13_FEATURES
240 config HAVE_MARCH_Z15_FEATURES
242 select HAVE_MARCH_Z14_FEATURES
245 prompt "Processor type"
249 bool "IBM zSeries model z800 and z900"
250 select HAVE_MARCH_Z900_FEATURES
251 depends on $(cc-option,-march=z900)
253 Select this to enable optimizations for model z800/z900 (2064 and
254 2066 series). This will enable some optimizations that are not
255 available on older ESA/390 (31 Bit) only CPUs.
258 bool "IBM zSeries model z890 and z990"
259 select HAVE_MARCH_Z990_FEATURES
260 depends on $(cc-option,-march=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
268 select HAVE_MARCH_Z9_109_FEATURES
269 depends on $(cc-option,-march=z9-109)
271 Select this to enable optimizations for IBM System z9 (2094 and
272 2096 series). The kernel will be slightly faster but will not work
276 bool "IBM System z10"
277 select HAVE_MARCH_Z10_FEATURES
278 depends on $(cc-option,-march=z10)
280 Select this to enable optimizations for IBM System z10 (2097 and
281 2098 series). The kernel will be slightly faster but will not work
285 bool "IBM zEnterprise 114 and 196"
286 select HAVE_MARCH_Z196_FEATURES
287 depends on $(cc-option,-march=z196)
289 Select this to enable optimizations for IBM zEnterprise 114 and 196
290 (2818 and 2817 series). The kernel will be slightly faster but will
291 not work on older machines.
294 bool "IBM zBC12 and zEC12"
295 select HAVE_MARCH_ZEC12_FEATURES
296 depends on $(cc-option,-march=zEC12)
298 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
299 2827 series). The kernel will be slightly faster but will not work on
303 bool "IBM z13s and z13"
304 select HAVE_MARCH_Z13_FEATURES
305 depends on $(cc-option,-march=z13)
307 Select this to enable optimizations for IBM z13s and z13 (2965 and
308 2964 series). The kernel will be slightly faster but will not work on
312 bool "IBM z14 ZR1 and z14"
313 select HAVE_MARCH_Z14_FEATURES
314 depends on $(cc-option,-march=z14)
316 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
317 and 3906 series). The kernel will be slightly faster but will not
318 work on older machines.
322 select HAVE_MARCH_Z15_FEATURES
323 depends on $(cc-option,-march=z15)
325 Select this to enable optimizations for IBM z15 (8562
326 and 8561 series). The kernel will be slightly faster but will not
327 work on older machines.
331 config MARCH_Z900_TUNE
332 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
334 config MARCH_Z990_TUNE
335 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
337 config MARCH_Z9_109_TUNE
338 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
340 config MARCH_Z10_TUNE
341 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
343 config MARCH_Z196_TUNE
344 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
346 config MARCH_ZEC12_TUNE
347 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
349 config MARCH_Z13_TUNE
350 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
352 config MARCH_Z14_TUNE
353 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
355 config MARCH_Z15_TUNE
356 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
359 prompt "Tune code generation"
362 Cause the compiler to tune (-mtune) the generated code for a machine.
363 This will make the code run faster on the selected machine but
364 somewhat slower on other machines.
365 This option only changes how the compiler emits instructions, not the
366 selection of instructions itself, so the resulting kernel will run on
372 Tune the generated code for the target processor for which the kernel
376 bool "IBM zSeries model z800 and z900"
377 depends on $(cc-option,-mtune=z900)
380 bool "IBM zSeries model z890 and z990"
381 depends on $(cc-option,-mtune=z990)
385 depends on $(cc-option,-mtune=z9-109)
388 bool "IBM System z10"
389 depends on $(cc-option,-mtune=z10)
392 bool "IBM zEnterprise 114 and 196"
393 depends on $(cc-option,-mtune=z196)
396 bool "IBM zBC12 and zEC12"
397 depends on $(cc-option,-mtune=zEC12)
400 bool "IBM z13s and z13"
401 depends on $(cc-option,-mtune=z13)
404 bool "IBM z14 ZR1 and z14"
405 depends on $(cc-option,-mtune=z14)
409 depends on $(cc-option,-mtune=z15)
418 prompt "Kernel support for 31 bit emulation"
419 select COMPAT_BINFMT_ELF if BINFMT_ELF
420 select ARCH_WANT_OLD_COMPAT_IPC
421 select COMPAT_OLD_SIGACTION
425 Select this option if you want to enable your system kernel to
426 handle system-calls from ELF binaries for 31 bit ESA. This option
427 (and some other stuff like libraries and such) is needed for
428 executing 31 bit applications. It is safe to say "Y".
431 def_bool COMPAT && !CC_IS_CLANG
433 config SYSVIPC_COMPAT
434 def_bool y if COMPAT && SYSVIPC
440 int "Maximum number of CPUs (2-512)"
444 This allows you to specify the maximum number of CPUs which this
445 kernel will support. The maximum supported value is 512 and the
446 minimum value which makes sense is 2.
448 This is purely to save memory - each supported CPU adds
449 approximately sixteen kilobytes to the kernel image.
454 # Some NUMA nodes have memory ranges that span
455 # other nodes. Even though a pfn is valid and
456 # between a node's start and end pfns, it may not
457 # reside on that node. See memmap_init_zone()
458 # for details. <- They meant memory holes!
459 config NODES_SPAN_OTHER_NODES
464 depends on SCHED_TOPOLOGY
469 This option adds NUMA support to the kernel.
471 An operation mode can be selected by appending
472 numa=<method> to the kernel command line.
474 The default behaviour is identical to appending numa=plain to
475 the command line. This will create just one node with all
476 available memory and all CPUs in it.
479 int "Maximum NUMA nodes (as a power of 2)"
484 Specify the maximum number of NUMA nodes available on the target
485 system. Increases memory reserved to accommodate various tables.
487 menu "Select NUMA modes"
491 bool "NUMA emulation"
494 Numa emulation mode will split the available system memory into
495 equal chunks which then are distributed over the configured number
496 of nodes in a round-robin manner.
498 The number of fake nodes is limited by the number of available memory
499 chunks (i.e. memory size / fake size) and the number of supported
502 The CPUs are assigned to the nodes in a way that partially respects
503 the original machine topology (if supported by the machine).
504 Fair distribution of the CPUs is not guaranteed.
507 hex "NUMA emulation memory chunk size"
509 range 0x400000 0x100000000
512 Select the default size by which the memory is chopped and then
513 assigned to emulated NUMA nodes.
515 This can be overridden by specifying
519 on the kernel command line where also suffixes K, M, G, and T are
536 config SCHED_TOPOLOGY
538 prompt "Topology scheduler support"
544 Topology scheduler support improves the CPU scheduler's decision
545 making when dealing with machines that have multi-threading,
546 multiple cores or multiple books.
548 source "kernel/Kconfig.hz"
555 bool "kexec file based system call"
559 depends on CRYPTO_SHA256
560 depends on CRYPTO_SHA256_S390
562 Enable the kexec file based system call. In contrast to the normal
563 kexec system call this system call takes file descriptors for the
564 kernel and initramfs as arguments.
566 config ARCH_HAS_KEXEC_PURGATORY
568 depends on KEXEC_FILE
571 bool "Verify kernel signature during kexec_file_load() syscall"
572 depends on KEXEC_FILE && MODULE_SIG_FORMAT
574 This option makes kernel signature verification mandatory for
575 the kexec_file_load() syscall.
577 In addition to that option, you need to enable signature
578 verification for the corresponding kernel image type being
579 loaded in order for this to work.
583 prompt "s390 architectural random number generation API"
585 Enable the s390 architectural random number generation API
586 to provide random data for all consumers within the Linux
589 When enabled the arch_random_* functions declared in linux/random.h
590 are implemented. The implementation is based on the s390 CPACF
591 instruction subfunction TRNG which provides a real true random
598 prompt "Enable modified branch prediction for the kernel by default"
600 If this option is selected the kernel will switch to a modified
601 branch prediction mode if the firmware interface is available.
602 The modified branch prediction mode improves the behaviour in
603 regard to speculative execution.
605 With the option enabled the kernel parameter "nobp=0" or "nospec"
606 can be used to run the kernel in the normal branch prediction mode.
608 With the option disabled the modified branch prediction mode is
609 enabled with the "nobp=1" kernel parameter.
615 prompt "Avoid speculative indirect branches in the kernel"
617 Compile the kernel with the expoline compiler options to guard
618 against kernel-to-user data leaks by avoiding speculative indirect
620 Requires a compiler with -mindirect-branch=thunk support for full
621 protection. The kernel may run slower.
626 prompt "Expoline default"
628 default EXPOLINE_FULL
631 bool "spectre_v2=off"
634 bool "spectre_v2=auto"
642 bool "Build a relocatable kernel"
643 select MODULE_REL_CRCS if MODVERSIONS
646 This builds a kernel image that retains relocation information
647 so it can be loaded at an arbitrary address.
648 The kernel is linked as a position-independent executable (PIE)
649 and contains dynamic relocations which are processed early in the
651 The relocations make the kernel image about 15% larger (compressed
652 10%), but are discarded at runtime.
654 config RANDOMIZE_BASE
655 bool "Randomize the address of the kernel image (KASLR)"
656 depends on RELOCATABLE
659 In support of Kernel Address Space Layout Randomization (KASLR),
660 this randomizes the address at which the kernel image is loaded,
661 as a security feature that deters exploit attempts relying on
662 knowledge of the location of kernel internals.
668 config ARCH_SPARSEMEM_ENABLE
670 select SPARSEMEM_VMEMMAP_ENABLE
671 select SPARSEMEM_VMEMMAP
673 config ARCH_SPARSEMEM_DEFAULT
676 config ARCH_ENABLE_MEMORY_HOTPLUG
677 def_bool y if SPARSEMEM
679 config ARCH_ENABLE_MEMORY_HOTREMOVE
682 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
685 config FORCE_MAX_ZONEORDER
689 config MAX_PHYSMEM_BITS
690 int "Maximum size of supported physical memory in bits (42-53)"
694 This option specifies the maximum supported size of physical memory
695 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
696 Increasing the number of bits also increases the kernel image size.
697 By default 46 bits (64TB) are supported.
701 prompt "Pack kernel stack"
703 This option enables the compiler option -mkernel-backchain if it
704 is available. If the option is available the compiler supports
705 the new stack layout which dramatically reduces the minimum stack
706 frame size. With an old compiler a non-leaf function needs a
707 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
708 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
709 and 24 byte on 64 bit.
711 Say Y if you are unsure.
715 depends on !VMAP_STACK
716 prompt "Detect kernel stack overflow"
718 This option enables the compiler option -mstack-guard and
719 -mstack-size if they are available. If the compiler supports them
720 it will emit additional code to each function prolog to trigger
721 an illegal operation if the kernel stack is about to overflow.
723 Say N if you are unsure.
726 int "Size of the guard area (128-1024)"
728 depends on CHECK_STACK
731 This allows you to specify the size of the guard area at the lower
732 end of the kernel stack. If the kernel stack points into the guard
733 area on function entry an illegal operation is triggered. The size
734 needs to be a power of 2. Please keep in mind that the size of an
735 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
736 The minimum size for the stack guard should be 256 for 31 bit and
739 config WARN_DYNAMIC_STACK
741 prompt "Emit compiler warnings for function with dynamic stack usage"
743 This option enables the compiler option -mwarn-dynamicstack. If the
744 compiler supports this options generates warnings for functions
745 that dynamically allocate stack space using alloca.
747 Say N if you are unsure.
755 prompt "QDIO support"
757 This driver provides the Queued Direct I/O base support for
760 To compile this driver as a module, choose M here: the
761 module will be called qdio.
767 config PCI_NR_FUNCTIONS
768 int "Maximum number of PCI functions (1-4096)"
772 This allows you to specify the maximum number of PCI functions which
773 this kernel will support.
782 prompt "Support for CHSC subchannels"
784 This driver allows usage of CHSC subchannels. A CHSC subchannel
785 is usually present on LPAR only.
786 The driver creates a device /dev/chsc, which may be used to
787 obtain I/O configuration information about the machine and
788 to issue asynchronous chsc commands (DANGEROUS).
789 You will usually only want to use this interface on a special
790 LPAR designated for system management.
792 To compile this driver as a module, choose M here: the
793 module will be called chsc_sch.
799 prompt "SCM bus driver"
801 Bus driver for Storage Class Memory.
805 prompt "Support for EADM subchannels"
808 This driver allows usage of EADM subchannels. EADM subchannels act
809 as a communication vehicle for SCM increments.
811 To compile this driver as a module, choose M here: the
812 module will be called eadm_sch.
816 prompt "Support for VFIO-CCW subchannels"
817 depends on S390_CCW_IOMMU && VFIO_MDEV
819 This driver allows usage of I/O subchannels via VFIO-CCW.
821 To compile this driver as a module, choose M here: the
822 module will be called vfio_ccw.
826 prompt "VFIO support for AP devices"
827 depends on S390_AP_IOMMU && VFIO_MDEV_DEVICE && KVM
829 This driver grants access to Adjunct Processor (AP) devices
830 via the VFIO mediated device interface.
832 To compile this driver as a module, choose M here: the module
833 will be called vfio_ap.
840 bool "kernel crash dumps"
843 Generate crash dump after being started by kexec.
844 Crash dump kernels are loaded in the main kernel with kexec-tools
845 into a specially reserved region and then later executed after
846 a crash by kdump/kexec.
847 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this.
848 This option also enables s390 zfcpdump.
849 See also <file:Documentation/s390/zfcpdump.rst>
855 prompt "Enable seccomp to safely compute untrusted bytecode"
858 This kernel feature is useful for number crunching applications
859 that may need to compute untrusted bytecode during their
860 execution. By using pipes or other transports made available to
861 the process as file descriptors supporting the read/write
862 syscalls, it's possible to isolate those applications in
863 their own address space using seccomp. Once seccomp is
864 enabled via /proc/<pid>/seccomp, it cannot be disabled
865 and the task is only allowed to execute a few safe syscalls
866 defined by each seccomp mode.
870 menu "Power Management"
872 config ARCH_HIBERNATION_POSSIBLE
875 source "kernel/power/Kconfig"
884 default (SMC || CCWGROUP)
886 menu "Virtualization"
888 config PROTECTED_VIRTUALIZATION_GUEST
890 prompt "Protected virtualization guest support"
892 Select this option, if you want to be able to run this
893 kernel as a protected virtualization KVM guest.
894 Protected virtualization capable machines have a mini hypervisor
895 located at machine level (an ultravisor). With help of the
896 Ultravisor, KVM will be able to run "protected" VMs, special
897 VMs whose memory and management data are unavailable to KVM.
901 prompt "Pseudo page fault support"
903 Select this option, if you want to use PFAULT pseudo page fault
904 handling under VM. If running native or in LPAR, this option
905 has no effect. If your VM does not support PFAULT, PAGEEX
906 pseudo page fault handling will be used.
907 Note that VM 4.2 supports PFAULT but has a bug in its
908 implementation that causes some problems.
909 Everybody who wants to run Linux under VM != VM4.2 should select
914 prompt "Cooperative memory management"
916 Select this option, if you want to enable the kernel interface
917 to reduce the memory size of the system. This is accomplished
918 by allocating pages of memory and put them "on hold". This only
919 makes sense for a system running under VM where the unused pages
920 will be reused by VM for other guest systems. The interface
921 allows an external monitor to balance memory of many systems.
922 Everybody who wants to run Linux under VM should select this
927 prompt "IUCV special message interface to cooperative memory management"
928 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
930 Select this option to enable the special message interface to
931 the cooperative memory management.
935 prompt "Linux - VM Monitor Stream, base infrastructure"
938 This provides a kernel interface for creating and updating z/VM APPLDATA
939 monitor records. The monitor records are updated at certain time
940 intervals, once the timer is started.
941 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
942 i.e. enables or disables monitoring on the Linux side.
943 A custom interval value (in seconds) can be written to
944 /proc/appldata/interval.
946 Defaults are 60 seconds interval and timer off.
947 The /proc entries can also be read from, showing the current settings.
951 prompt "Monitor memory management statistics"
952 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
954 This provides memory management related data to the Linux - VM Monitor
955 Stream, like paging/swapping rate, memory utilisation, etc.
956 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
957 APPLDATA monitor record, i.e. enables or disables monitoring this record
961 The /proc entry can also be read from, showing the current settings.
963 This can also be compiled as a module, which will be called
968 prompt "Monitor OS statistics"
969 depends on APPLDATA_BASE
971 This provides OS related data to the Linux - VM Monitor Stream, like
972 CPU utilisation, etc.
973 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
974 APPLDATA monitor record, i.e. enables or disables monitoring this record
978 This can also be compiled as a module, which will be called
981 config APPLDATA_NET_SUM
983 prompt "Monitor overall network statistics"
984 depends on APPLDATA_BASE && NET
986 This provides network related data to the Linux - VM Monitor Stream,
987 currently there is only a total sum of network I/O statistics, no
989 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
990 APPLDATA monitor record, i.e. enables or disables monitoring this record
994 This can also be compiled as a module, which will be called
999 prompt "s390 hypervisor file system support"
1000 select SYS_HYPERVISOR
1002 This is a virtual file system intended to provide accounting
1003 information in an s390 hypervisor environment.
1005 source "arch/s390/kvm/Kconfig"
1009 prompt "s390 support for virtio devices"
1011 select VIRTUALIZATION
1013 select VIRTIO_CONSOLE
1015 Enabling this option adds support for virtio based paravirtual device
1018 Select this option if you want to run the kernel as a guest under
1025 config S390_UNWIND_SELFTEST
1027 prompt "Test unwind functions"
1029 This option enables s390 specific stack unwinder testing kernel
1030 module. This option is not useful for distributions or general
1031 kernels, but only for kernel developers working on architecture code.
1033 Say N if you are unsure.