| blob | c64b2987d10810fb895edcb8b7b642ac9ad06913 |
1 # SPDX-License-Identifier: GPL-2.0
2 config MMU
3 def_bool y
5 config CPU_BIG_ENDIAN
6 def_bool y
8 config LOCKDEP_SUPPORT
9 def_bool y
11 config STACKTRACE_SUPPORT
12 def_bool y
14 config ARCH_HAS_ILOG2_U32
15 def_bool n
17 config ARCH_HAS_ILOG2_U64
18 def_bool n
20 config ARCH_PROC_KCORE_TEXT
21 def_bool y
23 config GENERIC_HWEIGHT
24 def_bool !HAVE_MARCH_Z196_FEATURES
26 config GENERIC_BUG
27 def_bool y if BUG
29 config GENERIC_BUG_RELATIVE_POINTERS
30 def_bool y
32 config GENERIC_LOCKBREAK
33 def_bool y if PREEMPTION
35 config PGSTE
36 def_bool y if KVM
38 config AUDIT_ARCH
39 def_bool y
41 config NO_IOPORT_MAP
42 def_bool y
44 config PCI_QUIRKS
45 def_bool n
47 config ARCH_SUPPORTS_UPROBES
48 def_bool y
50 config KASAN_SHADOW_OFFSET
51 hex
52 depends on KASAN
53 default 0x1C000000000000
55 config GCC_ASM_FLAG_OUTPUT_BROKEN
56 def_bool CC_IS_GCC && GCC_VERSION < 140200
57 help
58 GCC versions before 14.2.0 may die with an internal
59 compiler error in some configurations if flag output
60 operands are used within inline assemblies.
62 config S390
63 def_bool y
64 #
65 # Note: keep this list sorted alphabetically
66 #
67 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
68 select ALTERNATE_USER_ADDRESS_SPACE
69 select ARCH_32BIT_USTAT_F_TINODE
70 select ARCH_BINFMT_ELF_STATE
71 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
72 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM
73 select ARCH_ENABLE_MEMORY_HOTREMOVE
74 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
75 select ARCH_HAS_CURRENT_STACK_POINTER
76 select ARCH_HAS_DEBUG_VIRTUAL
77 select ARCH_HAS_DEBUG_VM_PGTABLE
78 select ARCH_HAS_DEBUG_WX
79 select ARCH_HAS_DEVMEM_IS_ALLOWED
80 select ARCH_HAS_DMA_OPS if PCI
81 select ARCH_HAS_ELF_RANDOMIZE
82 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
83 select ARCH_HAS_FORTIFY_SOURCE
84 select ARCH_HAS_GCOV_PROFILE_ALL
85 select ARCH_HAS_GIGANTIC_PAGE
86 select ARCH_HAS_KCOV
87 select ARCH_HAS_MEMBARRIER_SYNC_CORE
88 select ARCH_HAS_MEM_ENCRYPT
89 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
90 select ARCH_HAS_PTE_SPECIAL
91 select ARCH_HAS_SCALED_CPUTIME
92 select ARCH_HAS_SET_DIRECT_MAP
93 select ARCH_HAS_SET_MEMORY
94 select ARCH_HAS_STRICT_KERNEL_RWX
95 select ARCH_HAS_STRICT_MODULE_RWX
96 select ARCH_HAS_SYSCALL_WRAPPER
97 select ARCH_HAS_UBSAN
98 select ARCH_HAS_VDSO_TIME_DATA
99 select ARCH_HAVE_NMI_SAFE_CMPXCHG
100 select ARCH_INLINE_READ_LOCK
101 select ARCH_INLINE_READ_LOCK_BH
102 select ARCH_INLINE_READ_LOCK_IRQ
103 select ARCH_INLINE_READ_LOCK_IRQSAVE
104 select ARCH_INLINE_READ_TRYLOCK
105 select ARCH_INLINE_READ_UNLOCK
106 select ARCH_INLINE_READ_UNLOCK_BH
107 select ARCH_INLINE_READ_UNLOCK_IRQ
108 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
109 select ARCH_INLINE_SPIN_LOCK
110 select ARCH_INLINE_SPIN_LOCK_BH
111 select ARCH_INLINE_SPIN_LOCK_IRQ
112 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
113 select ARCH_INLINE_SPIN_TRYLOCK
114 select ARCH_INLINE_SPIN_TRYLOCK_BH
115 select ARCH_INLINE_SPIN_UNLOCK
116 select ARCH_INLINE_SPIN_UNLOCK_BH
117 select ARCH_INLINE_SPIN_UNLOCK_IRQ
118 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
119 select ARCH_INLINE_WRITE_LOCK
120 select ARCH_INLINE_WRITE_LOCK_BH
121 select ARCH_INLINE_WRITE_LOCK_IRQ
122 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
123 select ARCH_INLINE_WRITE_TRYLOCK
124 select ARCH_INLINE_WRITE_UNLOCK
125 select ARCH_INLINE_WRITE_UNLOCK_BH
126 select ARCH_INLINE_WRITE_UNLOCK_IRQ
127 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
128 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
129 select ARCH_STACKWALK
130 select ARCH_SUPPORTS_ATOMIC_RMW
131 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
132 select ARCH_SUPPORTS_HUGETLBFS
133 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG
134 select ARCH_SUPPORTS_NUMA_BALANCING
135 select ARCH_SUPPORTS_PER_VMA_LOCK
136 select ARCH_USE_BUILTIN_BSWAP
137 select ARCH_USE_CMPXCHG_LOCKREF
138 select ARCH_USE_SYM_ANNOTATIONS
139 select ARCH_WANTS_NO_INSTR
140 select ARCH_WANT_DEFAULT_BPF_JIT
141 select ARCH_WANT_IPC_PARSE_VERSION
142 select ARCH_WANT_KERNEL_PMD_MKWRITE
143 select ARCH_WANT_LD_ORPHAN_WARN
144 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
145 select BUILDTIME_TABLE_SORT
146 select CLONE_BACKWARDS2
147 select DCACHE_WORD_ACCESS if !KMSAN
148 select DYNAMIC_FTRACE if FUNCTION_TRACER
149 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC
150 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC
151 select GENERIC_ALLOCATOR
152 select GENERIC_CPU_DEVICES
153 select GENERIC_CPU_AUTOPROBE
154 select GENERIC_CPU_VULNERABILITIES
155 select GENERIC_ENTRY
156 select GENERIC_GETTIMEOFDAY
157 select GENERIC_PTDUMP
158 select GENERIC_SMP_IDLE_THREAD
159 select GENERIC_TIME_VSYSCALL
160 select GENERIC_VDSO_TIME_NS
161 select GENERIC_IOREMAP if PCI
162 select HAVE_ALIGNED_STRUCT_PAGE
163 select HAVE_ARCH_AUDITSYSCALL
164 select HAVE_ARCH_JUMP_LABEL
165 select HAVE_ARCH_JUMP_LABEL_RELATIVE
166 select HAVE_ARCH_KASAN
167 select HAVE_ARCH_KASAN_VMALLOC
168 select HAVE_ARCH_KCSAN
169 select HAVE_ARCH_KMSAN
170 select HAVE_ARCH_KFENCE
171 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
172 select HAVE_ARCH_SECCOMP_FILTER
173 select HAVE_ARCH_SOFT_DIRTY
174 select HAVE_ARCH_STACKLEAK
175 select HAVE_ARCH_TRACEHOOK
176 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
177 select HAVE_ARCH_VMAP_STACK
178 select HAVE_ASM_MODVERSIONS
179 select HAVE_CMPXCHG_DOUBLE
180 select HAVE_CMPXCHG_LOCAL
181 select HAVE_DEBUG_KMEMLEAK
182 select HAVE_DMA_CONTIGUOUS
183 select HAVE_DYNAMIC_FTRACE
184 select HAVE_DYNAMIC_FTRACE_WITH_ARGS
185 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
186 select HAVE_DYNAMIC_FTRACE_WITH_REGS
187 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES
188 select HAVE_EFFICIENT_UNALIGNED_ACCESS
189 select HAVE_GUP_FAST
190 select HAVE_FENTRY
191 select HAVE_FTRACE_MCOUNT_RECORD
192 select HAVE_FUNCTION_ARG_ACCESS_API
193 select HAVE_FUNCTION_ERROR_INJECTION
194 select HAVE_FUNCTION_GRAPH_RETVAL
195 select HAVE_FUNCTION_GRAPH_TRACER
196 select HAVE_FUNCTION_TRACER
197 select HAVE_GCC_PLUGINS
198 select HAVE_GENERIC_VDSO
199 select HAVE_IOREMAP_PROT if PCI
200 select HAVE_KERNEL_BZIP2
201 select HAVE_KERNEL_GZIP
202 select HAVE_KERNEL_LZ4
203 select HAVE_KERNEL_LZMA
204 select HAVE_KERNEL_LZO
205 select HAVE_KERNEL_UNCOMPRESSED
206 select HAVE_KERNEL_XZ
207 select HAVE_KERNEL_ZSTD
208 select HAVE_KPROBES
209 select HAVE_KPROBES_ON_FTRACE
210 select HAVE_KRETPROBES
211 select HAVE_LIVEPATCH
212 select HAVE_MEMBLOCK_PHYS_MAP
213 select HAVE_MOD_ARCH_SPECIFIC
214 select HAVE_NMI
215 select HAVE_NOP_MCOUNT
216 select HAVE_PAGE_SIZE_4KB
217 select HAVE_PCI
218 select HAVE_PERF_EVENTS
219 select HAVE_PERF_REGS
220 select HAVE_PERF_USER_STACK_DUMP
221 select HAVE_REGS_AND_STACK_ACCESS_API
222 select HAVE_RELIABLE_STACKTRACE
223 select HAVE_RETHOOK
224 select HAVE_RSEQ
225 select HAVE_SAMPLE_FTRACE_DIRECT
226 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
227 select HAVE_SETUP_PER_CPU_AREA
228 select HAVE_SOFTIRQ_ON_OWN_STACK
229 select HAVE_SYSCALL_TRACEPOINTS
230 select HAVE_VIRT_CPU_ACCOUNTING
231 select HAVE_VIRT_CPU_ACCOUNTING_IDLE
232 select IOMMU_HELPER if PCI
233 select IOMMU_SUPPORT if PCI
234 select LOCK_MM_AND_FIND_VMA
235 select MMU_GATHER_MERGE_VMAS
236 select MMU_GATHER_NO_GATHER
237 select MMU_GATHER_RCU_TABLE_FREE
238 select MODULES_USE_ELF_RELA
239 select NEED_DMA_MAP_STATE if PCI
240 select NEED_PER_CPU_EMBED_FIRST_CHUNK
241 select NEED_SG_DMA_LENGTH if PCI
242 select OLD_SIGACTION
243 select OLD_SIGSUSPEND3
244 select PCI_DOMAINS if PCI
245 select PCI_MSI if PCI
246 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI
247 select SPARSE_IRQ
248 select SWIOTLB
249 select SYSCTL_EXCEPTION_TRACE
250 select THREAD_INFO_IN_TASK
251 select TRACE_IRQFLAGS_SUPPORT
252 select TTY
253 select USER_STACKTRACE_SUPPORT
254 select VDSO_GETRANDOM
255 select VIRT_CPU_ACCOUNTING
256 select ZONE_DMA
257 # Note: keep the above list sorted alphabetically
259 config SCHED_OMIT_FRAME_POINTER
260 def_bool y
262 config PGTABLE_LEVELS
263 int
264 default 5
266 source "kernel/livepatch/Kconfig"
268 config ARCH_SUPPORTS_KEXEC
269 def_bool y
271 config ARCH_SUPPORTS_KEXEC_FILE
272 def_bool y
274 config ARCH_SUPPORTS_KEXEC_SIG
275 def_bool MODULE_SIG_FORMAT
277 config ARCH_SUPPORTS_KEXEC_PURGATORY
278 def_bool y
280 config ARCH_SUPPORTS_CRASH_DUMP
281 def_bool y
282 help
283 Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this.
284 This option also enables s390 zfcpdump.
285 See also <file:Documentation/arch/s390/zfcpdump.rst>
287 config ARCH_DEFAULT_CRASH_DUMP
288 def_bool y
290 menu "Processor type and features"
292 config HAVE_MARCH_Z10_FEATURES
293 def_bool n
295 config HAVE_MARCH_Z196_FEATURES
296 def_bool n
297 select HAVE_MARCH_Z10_FEATURES
299 config HAVE_MARCH_ZEC12_FEATURES
300 def_bool n
301 select HAVE_MARCH_Z196_FEATURES
303 config HAVE_MARCH_Z13_FEATURES
304 def_bool n
305 select HAVE_MARCH_ZEC12_FEATURES
307 config HAVE_MARCH_Z14_FEATURES
308 def_bool n
309 select HAVE_MARCH_Z13_FEATURES
311 config HAVE_MARCH_Z15_FEATURES
312 def_bool n
313 select HAVE_MARCH_Z14_FEATURES
315 config HAVE_MARCH_Z16_FEATURES
316 def_bool n
317 select HAVE_MARCH_Z15_FEATURES
319 choice
320 prompt "Processor type"
321 default MARCH_Z196
323 config MARCH_Z10
324 bool "IBM System z10"
325 select HAVE_MARCH_Z10_FEATURES
326 depends on $(cc-option,-march=z10)
327 help
328 Select this to enable optimizations for IBM System z10 (2097 and 2098
329 series). This is the oldest machine generation currently supported.
331 config MARCH_Z196
332 bool "IBM zEnterprise 114 and 196"
333 select HAVE_MARCH_Z196_FEATURES
334 depends on $(cc-option,-march=z196)
335 help
336 Select this to enable optimizations for IBM zEnterprise 114 and 196
337 (2818 and 2817 series). The kernel will be slightly faster but will
338 not work on older machines.
340 config MARCH_ZEC12
341 bool "IBM zBC12 and zEC12"
342 select HAVE_MARCH_ZEC12_FEATURES
343 depends on $(cc-option,-march=zEC12)
344 help
345 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
346 2827 series). The kernel will be slightly faster but will not work on
347 older machines.
349 config MARCH_Z13
350 bool "IBM z13s and z13"
351 select HAVE_MARCH_Z13_FEATURES
352 depends on $(cc-option,-march=z13)
353 help
354 Select this to enable optimizations for IBM z13s and z13 (2965 and
355 2964 series). The kernel will be slightly faster but will not work on
356 older machines.
358 config MARCH_Z14
359 bool "IBM z14 ZR1 and z14"
360 select HAVE_MARCH_Z14_FEATURES
361 depends on $(cc-option,-march=z14)
362 help
363 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
364 and 3906 series). The kernel will be slightly faster but will not
365 work on older machines.
367 config MARCH_Z15
368 bool "IBM z15"
369 select HAVE_MARCH_Z15_FEATURES
370 depends on $(cc-option,-march=z15)
371 help
372 Select this to enable optimizations for IBM z15 (8562
373 and 8561 series). The kernel will be slightly faster but will not
374 work on older machines.
376 config MARCH_Z16
377 bool "IBM z16"
378 select HAVE_MARCH_Z16_FEATURES
379 depends on $(cc-option,-march=z16)
380 help
381 Select this to enable optimizations for IBM z16 (3931 and
382 3932 series).
384 endchoice
386 config MARCH_Z10_TUNE
387 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
389 config MARCH_Z196_TUNE
390 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
392 config MARCH_ZEC12_TUNE
393 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
395 config MARCH_Z13_TUNE
396 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
398 config MARCH_Z14_TUNE
399 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
401 config MARCH_Z15_TUNE
402 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
404 config MARCH_Z16_TUNE
405 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT
407 choice
408 prompt "Tune code generation"
409 default TUNE_DEFAULT
410 help
411 Cause the compiler to tune (-mtune) the generated code for a machine.
412 This will make the code run faster on the selected machine but
413 somewhat slower on other machines.
414 This option only changes how the compiler emits instructions, not the
415 selection of instructions itself, so the resulting kernel will run on
416 all other machines.
418 config TUNE_DEFAULT
419 bool "Default"
420 help
421 Tune the generated code for the target processor for which the kernel
422 will be compiled.
424 config TUNE_Z10
425 bool "IBM System z10"
427 config TUNE_Z196
428 bool "IBM zEnterprise 114 and 196"
429 depends on $(cc-option,-mtune=z196)
431 config TUNE_ZEC12
432 bool "IBM zBC12 and zEC12"
433 depends on $(cc-option,-mtune=zEC12)
435 config TUNE_Z13
436 bool "IBM z13s and z13"
437 depends on $(cc-option,-mtune=z13)
439 config TUNE_Z14
440 bool "IBM z14 ZR1 and z14"
441 depends on $(cc-option,-mtune=z14)
443 config TUNE_Z15
444 bool "IBM z15"
445 depends on $(cc-option,-mtune=z15)
447 config TUNE_Z16
448 bool "IBM z16"
449 depends on $(cc-option,-mtune=z16)
451 endchoice
453 config 64BIT
454 def_bool y
456 config COMMAND_LINE_SIZE
457 int "Maximum size of kernel command line"
458 default 4096
459 range 896 1048576
460 help
461 This allows you to specify the maximum length of the kernel command
462 line.
464 config COMPAT
465 def_bool n
466 prompt "Kernel support for 31 bit emulation"
467 select ARCH_WANT_OLD_COMPAT_IPC
468 select COMPAT_OLD_SIGACTION
469 select HAVE_UID16
470 depends on MULTIUSER
471 depends on !CC_IS_CLANG && !LD_IS_LLD
472 help
473 Select this option if you want to enable your system kernel to
474 handle system-calls from ELF binaries for 31 bit ESA. This option
475 (and some other stuff like libraries and such) is needed for
476 executing 31 bit applications.
478 If unsure say N.
480 config SMP
481 def_bool y
483 config NR_CPUS
484 int "Maximum number of CPUs (2-512)"
485 range 2 512
486 default "64"
487 help
488 This allows you to specify the maximum number of CPUs which this
489 kernel will support. The maximum supported value is 512 and the
490 minimum value which makes sense is 2.
492 This is purely to save memory - each supported CPU adds
493 approximately sixteen kilobytes to the kernel image.
495 config HOTPLUG_CPU
496 def_bool y
498 config NUMA
499 bool "NUMA support"
500 depends on SCHED_TOPOLOGY
501 default n
502 help
503 Enable NUMA support
505 This option adds NUMA support to the kernel.
507 config NODES_SHIFT
508 int
509 depends on NUMA
510 default "1"
512 config SCHED_SMT
513 def_bool n
515 config SCHED_MC
516 def_bool n
518 config SCHED_TOPOLOGY
519 def_bool y
520 prompt "Topology scheduler support"
521 select SCHED_SMT
522 select SCHED_MC
523 help
524 Topology scheduler support improves the CPU scheduler's decision
525 making when dealing with machines that have multi-threading,
526 multiple cores or multiple books.
528 config SCHED_TOPOLOGY_VERTICAL
529 def_bool y
530 bool "Use vertical CPU polarization by default"
531 depends on SCHED_TOPOLOGY
532 help
533 Use vertical CPU polarization by default if available.
534 The default CPU polarization is horizontal.
536 config HIPERDISPATCH_ON
537 def_bool y
538 bool "Use hiperdispatch on vertical polarization by default"
539 depends on SCHED_TOPOLOGY
540 depends on PROC_SYSCTL
541 help
542 Hiperdispatch aims to improve the CPU scheduler's decision
543 making when using vertical polarization by adjusting CPU
544 capacities dynamically. Set this option to use hiperdispatch
545 on vertical polarization by default. This can be overwritten
546 by sysctl's s390.hiperdispatch attribute later on.
548 source "kernel/Kconfig.hz"
550 config CERT_STORE
551 bool "Get user certificates via DIAG320"
552 depends on KEYS
553 select CRYPTO_LIB_SHA256
554 help
555 Enable this option if you want to access user-provided secure boot
556 certificates via DIAG 0x320.
558 These certificates will be made available via the keyring named
559 'cert_store'.
561 config KERNEL_NOBP
562 def_bool n
563 prompt "Enable modified branch prediction for the kernel by default"
564 help
565 If this option is selected the kernel will switch to a modified
566 branch prediction mode if the firmware interface is available.
567 The modified branch prediction mode improves the behaviour in
568 regard to speculative execution.
570 With the option enabled the kernel parameter "nobp=0" or "nospec"
571 can be used to run the kernel in the normal branch prediction mode.
573 With the option disabled the modified branch prediction mode is
574 enabled with the "nobp=1" kernel parameter.
576 If unsure, say N.
578 config EXPOLINE
579 def_bool n
580 depends on $(cc-option,-mindirect-branch=thunk)
581 prompt "Avoid speculative indirect branches in the kernel"
582 help
583 Compile the kernel with the expoline compiler options to guard
584 against kernel-to-user data leaks by avoiding speculative indirect
585 branches.
586 Requires a compiler with -mindirect-branch=thunk support for full
587 protection. The kernel may run slower.
589 If unsure, say N.
591 config EXPOLINE_EXTERN
592 def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \
593 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))
594 help
595 Generate expolines as external functions if the compiler supports it.
596 This option is required for some tooling like kpatch, if expolines
597 are enabled. The kernel is compiled with
598 -mindirect-branch=thunk-extern, which requires a newer compiler.
600 choice
601 prompt "Expoline default"
602 depends on EXPOLINE
603 default EXPOLINE_FULL
605 config EXPOLINE_OFF
606 bool "spectre_v2=off"
608 config EXPOLINE_AUTO
609 bool "spectre_v2=auto"
611 config EXPOLINE_FULL
612 bool "spectre_v2=on"
614 endchoice
616 config RELOCATABLE
617 def_bool y
618 help
619 This builds a kernel image that retains relocation information
620 so it can be loaded at an arbitrary address.
621 The relocations make the kernel image about 15% larger (compressed
622 10%), but are discarded at runtime.
623 Note: this option exists only for documentation purposes, please do
624 not remove it.
626 config RANDOMIZE_BASE
627 bool "Randomize the address of the kernel image (KASLR)"
628 default y
629 help
630 In support of Kernel Address Space Layout Randomization (KASLR),
631 this randomizes the address at which the kernel image is loaded,
632 as a security feature that deters exploit attempts relying on
633 knowledge of the location of kernel internals.
635 config RANDOMIZE_IDENTITY_BASE
636 bool "Randomize the address of the identity mapping base"
637 depends on RANDOMIZE_BASE
638 default DEBUG_VM
639 help
640 The identity mapping base address is pinned to zero by default.
641 Allow randomization of that base to expose otherwise missed
642 notion of physical and virtual addresses of data structures.
643 That does not have any impact on the base address at which the
644 kernel image is loaded.
646 If unsure, say N
648 config KERNEL_IMAGE_BASE
649 hex "Kernel image base address"
650 range 0x100000 0x1FFFFFE0000000 if !KASAN
651 range 0x100000 0x1BFFFFE0000000 if KASAN
652 default 0x3FFE0000000 if !KASAN
653 default 0x7FFFE0000000 if KASAN
654 help
655 This is the address at which the kernel image is loaded in case
656 Kernel Address Space Layout Randomization (KASLR) is disabled.
658 In case the Protected virtualization guest support is enabled the
659 Ultravisor imposes a virtual address limit. If the value of this
660 option leads to the kernel image exceeding the Ultravisor limit,
661 this option is ignored and the image is loaded below the limit.
663 If the value of this option leads to the kernel image overlapping
664 the virtual memory where other data structures are located, this
665 option is ignored and the image is loaded above the structures.
667 endmenu
669 menu "Memory setup"
671 config ARCH_SPARSEMEM_ENABLE
672 def_bool y
673 select SPARSEMEM_VMEMMAP_ENABLE
674 select SPARSEMEM_VMEMMAP
676 config ARCH_SPARSEMEM_DEFAULT
677 def_bool y
679 config MAX_PHYSMEM_BITS
680 int "Maximum size of supported physical memory in bits (42-53)"
681 range 42 53
682 default "46"
683 help
684 This option specifies the maximum supported size of physical memory
685 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
686 Increasing the number of bits also increases the kernel image size.
687 By default 46 bits (64TB) are supported.
689 config CHECK_STACK
690 def_bool y
691 depends on !VMAP_STACK
692 prompt "Detect kernel stack overflow"
693 help
694 This option enables the compiler option -mstack-guard and
695 -mstack-size if they are available. If the compiler supports them
696 it will emit additional code to each function prolog to trigger
697 an illegal operation if the kernel stack is about to overflow.
699 Say N if you are unsure.
701 config STACK_GUARD
702 int "Size of the guard area (128-1024)"
703 range 128 1024
704 depends on CHECK_STACK
705 default "256"
706 help
707 This allows you to specify the size of the guard area at the lower
708 end of the kernel stack. If the kernel stack points into the guard
709 area on function entry an illegal operation is triggered. The size
710 needs to be a power of 2. Please keep in mind that the size of an
711 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
712 The minimum size for the stack guard should be 256 for 31 bit and
713 512 for 64 bit.
715 endmenu
717 menu "I/O subsystem"
719 config QDIO
720 def_tristate y
721 prompt "QDIO support"
722 help
723 This driver provides the Queued Direct I/O base support for
724 IBM System z.
726 To compile this driver as a module, choose M here: the
727 module will be called qdio.
729 If unsure, say Y.
731 if PCI
733 config PCI_NR_FUNCTIONS
734 int "Maximum number of PCI functions (1-4096)"
735 range 1 4096
736 default "512"
737 help
738 This allows you to specify the maximum number of PCI functions which
739 this kernel will support.
741 endif # PCI
743 config HAS_IOMEM
744 def_bool PCI
746 config CHSC_SCH
747 def_tristate m
748 prompt "Support for CHSC subchannels"
749 help
750 This driver allows usage of CHSC subchannels. A CHSC subchannel
751 is usually present on LPAR only.
752 The driver creates a device /dev/chsc, which may be used to
753 obtain I/O configuration information about the machine and
754 to issue asynchronous chsc commands (DANGEROUS).
755 You will usually only want to use this interface on a special
756 LPAR designated for system management.
758 To compile this driver as a module, choose M here: the
759 module will be called chsc_sch.
761 If unsure, say N.
763 config SCM_BUS
764 def_bool y
765 prompt "SCM bus driver"
766 help
767 Bus driver for Storage Class Memory.
769 config EADM_SCH
770 def_tristate m
771 prompt "Support for EADM subchannels"
772 depends on SCM_BUS
773 help
774 This driver allows usage of EADM subchannels. EADM subchannels act
775 as a communication vehicle for SCM increments.
777 To compile this driver as a module, choose M here: the
778 module will be called eadm_sch.
780 config AP
781 def_tristate y
782 prompt "Support for Adjunct Processors (ap)"
783 help
784 This driver allows usage to Adjunct Processor (AP) devices via
785 the ap bus, cards and queues. Supported Adjunct Processors are
786 the CryptoExpress Cards (CEX).
788 To compile this driver as a module, choose M here: the
789 module will be called ap.
791 If unsure, say Y (default).
793 config AP_DEBUG
794 def_bool n
795 prompt "Enable debug features for Adjunct Processor (ap) devices"
796 depends on AP
797 help
798 Say 'Y' here to enable some additional debug features for Adjunct
799 Processor (ap) devices.
801 There will be some more sysfs attributes displayed for ap queues.
803 Do not enable on production level kernel build.
805 If unsure, say N.
807 config VFIO_CCW
808 def_tristate n
809 prompt "Support for VFIO-CCW subchannels"
810 depends on VFIO
811 select VFIO_MDEV
812 help
813 This driver allows usage of I/O subchannels via VFIO-CCW.
815 To compile this driver as a module, choose M here: the
816 module will be called vfio_ccw.
818 config VFIO_AP
819 def_tristate n
820 prompt "VFIO support for AP devices"
821 depends on KVM
822 depends on VFIO
823 depends on AP
824 select VFIO_MDEV
825 help
826 This driver grants access to Adjunct Processor (AP) devices
827 via the VFIO mediated device interface.
829 To compile this driver as a module, choose M here: the module
830 will be called vfio_ap.
832 endmenu
834 config CCW
835 def_bool y
837 config HAVE_PNETID
838 tristate
839 default (SMC || CCWGROUP)
841 menu "Virtualization"
843 config PFAULT
844 def_bool y
845 prompt "Pseudo page fault support"
846 help
847 Select this option, if you want to use PFAULT pseudo page fault
848 handling under VM. If running native or in LPAR, this option
849 has no effect. If your VM does not support PFAULT, PAGEEX
850 pseudo page fault handling will be used.
851 Note that VM 4.2 supports PFAULT but has a bug in its
852 implementation that causes some problems.
853 Everybody who wants to run Linux under VM != VM4.2 should select
854 this option.
856 config CMM
857 def_tristate n
858 prompt "Cooperative memory management"
859 help
860 Select this option, if you want to enable the kernel interface
861 to reduce the memory size of the system. This is accomplished
862 by allocating pages of memory and put them "on hold". This only
863 makes sense for a system running under VM where the unused pages
864 will be reused by VM for other guest systems. The interface
865 allows an external monitor to balance memory of many systems.
866 Everybody who wants to run Linux under VM should select this
867 option.
869 config CMM_IUCV
870 def_bool y
871 prompt "IUCV special message interface to cooperative memory management"
872 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
873 help
874 Select this option to enable the special message interface to
875 the cooperative memory management.
877 config APPLDATA_BASE
878 def_bool n
879 prompt "Linux - VM Monitor Stream, base infrastructure"
880 depends on PROC_SYSCTL
881 help
882 This provides a kernel interface for creating and updating z/VM APPLDATA
883 monitor records. The monitor records are updated at certain time
884 intervals, once the timer is started.
885 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
886 i.e. enables or disables monitoring on the Linux side.
887 A custom interval value (in seconds) can be written to
888 /proc/appldata/interval.
890 Defaults are 60 seconds interval and timer off.
891 The /proc entries can also be read from, showing the current settings.
893 config APPLDATA_MEM
894 def_tristate m
895 prompt "Monitor memory management statistics"
896 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
897 help
898 This provides memory management related data to the Linux - VM Monitor
899 Stream, like paging/swapping rate, memory utilisation, etc.
900 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
901 APPLDATA monitor record, i.e. enables or disables monitoring this record
902 on the z/VM side.
904 Default is disabled.
905 The /proc entry can also be read from, showing the current settings.
907 This can also be compiled as a module, which will be called
908 appldata_mem.o.
910 config APPLDATA_OS
911 def_tristate m
912 prompt "Monitor OS statistics"
913 depends on APPLDATA_BASE
914 help
915 This provides OS related data to the Linux - VM Monitor Stream, like
916 CPU utilisation, etc.
917 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
918 APPLDATA monitor record, i.e. enables or disables monitoring this record
919 on the z/VM side.
921 Default is disabled.
922 This can also be compiled as a module, which will be called
923 appldata_os.o.
925 config APPLDATA_NET_SUM
926 def_tristate m
927 prompt "Monitor overall network statistics"
928 depends on APPLDATA_BASE && NET
929 help
930 This provides network related data to the Linux - VM Monitor Stream,
931 currently there is only a total sum of network I/O statistics, no
932 per-interface data.
933 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
934 APPLDATA monitor record, i.e. enables or disables monitoring this record
935 on the z/VM side.
937 Default is disabled.
938 This can also be compiled as a module, which will be called
939 appldata_net_sum.o.
941 config S390_HYPFS
942 def_bool y
943 prompt "s390 hypervisor information"
944 help
945 This provides several binary files at (debugfs)/s390_hypfs/ to
946 provide accounting information in an s390 hypervisor environment.
948 config S390_HYPFS_FS
949 def_bool n
950 prompt "s390 hypervisor file system support"
951 select SYS_HYPERVISOR
952 depends on S390_HYPFS
953 help
954 This is a virtual file system intended to provide accounting
955 information in an s390 hypervisor environment. This file system
956 is deprecated and should not be used.
958 Say N if you are unsure.
960 source "arch/s390/kvm/Kconfig"
962 config S390_GUEST
963 def_bool y
964 prompt "s390 support for virtio devices"
965 select TTY
966 select VIRTUALIZATION
967 select VIRTIO
968 help
969 Enabling this option adds support for virtio based paravirtual device
970 drivers on s390.
972 Select this option if you want to run the kernel as a guest under
973 the KVM hypervisor.
975 endmenu
977 config S390_MODULES_SANITY_TEST_HELPERS
978 def_bool n
980 menu "Selftests"
982 config S390_UNWIND_SELFTEST
983 def_tristate n
984 depends on KUNIT
985 default KUNIT_ALL_TESTS
986 prompt "Test unwind functions"
987 help
988 This option enables s390 specific stack unwinder testing kernel
989 module. This option is not useful for distributions or general
990 kernels, but only for kernel developers working on architecture code.
992 Say N if you are unsure.
994 config S390_KPROBES_SANITY_TEST
995 def_tristate n
996 prompt "Enable s390 specific kprobes tests"
997 depends on KPROBES
998 depends on KUNIT
999 help
1000 This option enables an s390 specific kprobes test module. This option
1001 is not useful for distributions or general kernels, but only for kernel
1002 developers working on architecture code.
1004 Say N if you are unsure.
1006 config S390_MODULES_SANITY_TEST
1007 def_tristate n
1008 depends on KUNIT
1009 default KUNIT_ALL_TESTS
1010 prompt "Enable s390 specific modules tests"
1011 select S390_MODULES_SANITY_TEST_HELPERS
1012 help
1013 This option enables an s390 specific modules test. This option is
1014 not useful for distributions or general kernels, but only for
1015 kernel developers working on architecture code.
1017 Say N if you are unsure.
1018 endmenu