1# SPDX-License-Identifier: GPL-2.0 2config MMU 3 def_bool y 4 5config CPU_BIG_ENDIAN 6 def_bool y 7 8config LOCKDEP_SUPPORT 9 def_bool y 10 11config STACKTRACE_SUPPORT 12 def_bool y 13 14config ARCH_HAS_ILOG2_U32 15 def_bool n 16 17config ARCH_HAS_ILOG2_U64 18 def_bool n 19 20config ARCH_PROC_KCORE_TEXT 21 def_bool y 22 23config GENERIC_HWEIGHT 24 def_bool !HAVE_MARCH_Z196_FEATURES 25 26config GENERIC_BUG 27 def_bool y if BUG 28 29config GENERIC_BUG_RELATIVE_POINTERS 30 def_bool y 31 32config GENERIC_LOCKBREAK 33 def_bool y if PREEMPTION 34 35config PGSTE 36 def_bool y if KVM 37 38config AUDIT_ARCH 39 def_bool y 40 41config NO_IOPORT_MAP 42 def_bool y 43 44config PCI_QUIRKS 45 def_bool n 46 47config ARCH_SUPPORTS_UPROBES 48 def_bool y 49 50config KASAN_SHADOW_OFFSET 51 hex 52 depends on KASAN 53 default 0x1C000000000000 54 55config 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. 61 62config 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_CRC32 76 select ARCH_HAS_CURRENT_STACK_POINTER 77 select ARCH_HAS_DEBUG_VIRTUAL 78 select ARCH_HAS_DEBUG_VM_PGTABLE 79 select ARCH_HAS_DEBUG_WX 80 select ARCH_HAS_DEVMEM_IS_ALLOWED 81 select ARCH_HAS_DMA_OPS if PCI 82 select ARCH_HAS_ELF_RANDOMIZE 83 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 84 select ARCH_HAS_FORTIFY_SOURCE 85 select ARCH_HAS_GCOV_PROFILE_ALL 86 select ARCH_HAS_GIGANTIC_PAGE 87 select ARCH_HAS_KCOV 88 select ARCH_HAS_MEMBARRIER_SYNC_CORE 89 select ARCH_HAS_MEM_ENCRYPT 90 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 91 select ARCH_HAS_PREEMPT_LAZY 92 select ARCH_HAS_PTE_SPECIAL 93 select ARCH_HAS_SCALED_CPUTIME 94 select ARCH_HAS_SET_DIRECT_MAP 95 select ARCH_HAS_SET_MEMORY 96 select ARCH_HAS_STRICT_KERNEL_RWX 97 select ARCH_HAS_STRICT_MODULE_RWX 98 select ARCH_HAS_SYSCALL_WRAPPER 99 select ARCH_HAS_UBSAN 100 select ARCH_HAS_VDSO_TIME_DATA 101 select ARCH_HAVE_NMI_SAFE_CMPXCHG 102 select ARCH_INLINE_READ_LOCK 103 select ARCH_INLINE_READ_LOCK_BH 104 select ARCH_INLINE_READ_LOCK_IRQ 105 select ARCH_INLINE_READ_LOCK_IRQSAVE 106 select ARCH_INLINE_READ_TRYLOCK 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_SPIN_LOCK 112 select ARCH_INLINE_SPIN_LOCK_BH 113 select ARCH_INLINE_SPIN_LOCK_IRQ 114 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 115 select ARCH_INLINE_SPIN_TRYLOCK 116 select ARCH_INLINE_SPIN_TRYLOCK_BH 117 select ARCH_INLINE_SPIN_UNLOCK 118 select ARCH_INLINE_SPIN_UNLOCK_BH 119 select ARCH_INLINE_SPIN_UNLOCK_IRQ 120 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 121 select ARCH_INLINE_WRITE_LOCK 122 select ARCH_INLINE_WRITE_LOCK_BH 123 select ARCH_INLINE_WRITE_LOCK_IRQ 124 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 125 select ARCH_INLINE_WRITE_TRYLOCK 126 select ARCH_INLINE_WRITE_UNLOCK 127 select ARCH_INLINE_WRITE_UNLOCK_BH 128 select ARCH_INLINE_WRITE_UNLOCK_IRQ 129 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 130 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE 131 select ARCH_STACKWALK 132 select ARCH_SUPPORTS_ATOMIC_RMW 133 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 134 select ARCH_SUPPORTS_HUGETLBFS 135 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG 136 select ARCH_SUPPORTS_NUMA_BALANCING 137 select ARCH_SUPPORTS_PER_VMA_LOCK 138 select ARCH_USE_BUILTIN_BSWAP 139 select ARCH_USE_CMPXCHG_LOCKREF 140 select ARCH_USE_SYM_ANNOTATIONS 141 select ARCH_WANTS_NO_INSTR 142 select ARCH_WANT_DEFAULT_BPF_JIT 143 select ARCH_WANT_IPC_PARSE_VERSION 144 select ARCH_WANT_KERNEL_PMD_MKWRITE 145 select ARCH_WANT_LD_ORPHAN_WARN 146 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 147 select BUILDTIME_TABLE_SORT 148 select CLONE_BACKWARDS2 149 select DCACHE_WORD_ACCESS if !KMSAN 150 select DYNAMIC_FTRACE if FUNCTION_TRACER 151 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 152 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 153 select GENERIC_ALLOCATOR 154 select GENERIC_CPU_DEVICES 155 select GENERIC_CPU_AUTOPROBE 156 select GENERIC_CPU_VULNERABILITIES 157 select GENERIC_ENTRY 158 select GENERIC_GETTIMEOFDAY 159 select GENERIC_PTDUMP 160 select GENERIC_SMP_IDLE_THREAD 161 select GENERIC_TIME_VSYSCALL 162 select GENERIC_VDSO_TIME_NS 163 select GENERIC_IOREMAP if PCI 164 select HAVE_ALIGNED_STRUCT_PAGE 165 select HAVE_ARCH_AUDITSYSCALL 166 select HAVE_ARCH_JUMP_LABEL 167 select HAVE_ARCH_JUMP_LABEL_RELATIVE 168 select HAVE_ARCH_KASAN 169 select HAVE_ARCH_KASAN_VMALLOC 170 select HAVE_ARCH_KCSAN 171 select HAVE_ARCH_KMSAN 172 select HAVE_ARCH_KFENCE 173 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 174 select HAVE_ARCH_SECCOMP_FILTER 175 select HAVE_ARCH_SOFT_DIRTY 176 select HAVE_ARCH_STACKLEAK 177 select HAVE_ARCH_TRACEHOOK 178 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 179 select HAVE_ARCH_VMAP_STACK 180 select HAVE_ASM_MODVERSIONS 181 select HAVE_CMPXCHG_DOUBLE 182 select HAVE_CMPXCHG_LOCAL 183 select HAVE_DEBUG_KMEMLEAK 184 select HAVE_DMA_CONTIGUOUS 185 select HAVE_DYNAMIC_FTRACE 186 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 187 select HAVE_FTRACE_REGS_HAVING_PT_REGS 188 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 189 select HAVE_DYNAMIC_FTRACE_WITH_REGS 190 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 191 select HAVE_EFFICIENT_UNALIGNED_ACCESS 192 select HAVE_GUP_FAST 193 select HAVE_FENTRY 194 select HAVE_FTRACE_GRAPH_FUNC 195 select HAVE_FTRACE_MCOUNT_RECORD 196 select HAVE_FUNCTION_ARG_ACCESS_API 197 select HAVE_FUNCTION_ERROR_INJECTION 198 select HAVE_FUNCTION_GRAPH_FREGS 199 select HAVE_FUNCTION_GRAPH_TRACER 200 select HAVE_FUNCTION_TRACER 201 select HAVE_GCC_PLUGINS 202 select HAVE_GENERIC_VDSO 203 select HAVE_IOREMAP_PROT if PCI 204 select HAVE_KERNEL_BZIP2 205 select HAVE_KERNEL_GZIP 206 select HAVE_KERNEL_LZ4 207 select HAVE_KERNEL_LZMA 208 select HAVE_KERNEL_LZO 209 select HAVE_KERNEL_UNCOMPRESSED 210 select HAVE_KERNEL_XZ 211 select HAVE_KERNEL_ZSTD 212 select HAVE_KPROBES 213 select HAVE_KPROBES_ON_FTRACE 214 select HAVE_KRETPROBES 215 select HAVE_LIVEPATCH 216 select HAVE_MEMBLOCK_PHYS_MAP 217 select HAVE_MOD_ARCH_SPECIFIC 218 select HAVE_NMI 219 select HAVE_NOP_MCOUNT 220 select HAVE_PAGE_SIZE_4KB 221 select HAVE_PCI 222 select HAVE_PERF_EVENTS 223 select HAVE_PERF_REGS 224 select HAVE_PERF_USER_STACK_DUMP 225 select HAVE_PREEMPT_DYNAMIC_KEY 226 select HAVE_REGS_AND_STACK_ACCESS_API 227 select HAVE_RELIABLE_STACKTRACE 228 select HAVE_RETHOOK 229 select HAVE_RSEQ 230 select HAVE_SAMPLE_FTRACE_DIRECT 231 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 232 select HAVE_SETUP_PER_CPU_AREA 233 select HAVE_SOFTIRQ_ON_OWN_STACK 234 select HAVE_SYSCALL_TRACEPOINTS 235 select HAVE_VIRT_CPU_ACCOUNTING 236 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 237 select IOMMU_HELPER if PCI 238 select IOMMU_SUPPORT if PCI 239 select KASAN_VMALLOC if KASAN 240 select LOCK_MM_AND_FIND_VMA 241 select MMU_GATHER_MERGE_VMAS 242 select MMU_GATHER_NO_GATHER 243 select MMU_GATHER_RCU_TABLE_FREE 244 select MODULES_USE_ELF_RELA 245 select NEED_DMA_MAP_STATE if PCI 246 select NEED_PER_CPU_EMBED_FIRST_CHUNK 247 select NEED_SG_DMA_LENGTH if PCI 248 select OLD_SIGACTION 249 select OLD_SIGSUSPEND3 250 select PCI_DOMAINS if PCI 251 select PCI_MSI if PCI 252 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 253 select SPARSE_IRQ 254 select SWIOTLB 255 select SYSCTL_EXCEPTION_TRACE 256 select THREAD_INFO_IN_TASK 257 select TRACE_IRQFLAGS_SUPPORT 258 select TTY 259 select USER_STACKTRACE_SUPPORT 260 select VDSO_GETRANDOM 261 select VIRT_CPU_ACCOUNTING 262 select VMAP_STACK 263 select ZONE_DMA 264 # Note: keep the above list sorted alphabetically 265 266config SCHED_OMIT_FRAME_POINTER 267 def_bool y 268 269config PGTABLE_LEVELS 270 int 271 default 5 272 273source "kernel/livepatch/Kconfig" 274 275config ARCH_SUPPORTS_KEXEC 276 def_bool y 277 278config ARCH_SUPPORTS_KEXEC_FILE 279 def_bool y 280 281config ARCH_SUPPORTS_KEXEC_SIG 282 def_bool MODULE_SIG_FORMAT 283 284config ARCH_SUPPORTS_KEXEC_PURGATORY 285 def_bool y 286 287config ARCH_SUPPORTS_CRASH_DUMP 288 def_bool y 289 help 290 Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this. 291 This option also enables s390 zfcpdump. 292 See also <file:Documentation/arch/s390/zfcpdump.rst> 293 294config ARCH_DEFAULT_CRASH_DUMP 295 def_bool y 296 297menu "Processor type and features" 298 299config HAVE_MARCH_Z10_FEATURES 300 def_bool n 301 302config HAVE_MARCH_Z196_FEATURES 303 def_bool n 304 select HAVE_MARCH_Z10_FEATURES 305 306config HAVE_MARCH_ZEC12_FEATURES 307 def_bool n 308 select HAVE_MARCH_Z196_FEATURES 309 310config HAVE_MARCH_Z13_FEATURES 311 def_bool n 312 select HAVE_MARCH_ZEC12_FEATURES 313 314config HAVE_MARCH_Z14_FEATURES 315 def_bool n 316 select HAVE_MARCH_Z13_FEATURES 317 318config HAVE_MARCH_Z15_FEATURES 319 def_bool n 320 select HAVE_MARCH_Z14_FEATURES 321 322config HAVE_MARCH_Z16_FEATURES 323 def_bool n 324 select HAVE_MARCH_Z15_FEATURES 325 326choice 327 prompt "Processor type" 328 default MARCH_Z196 329 330config MARCH_Z10 331 bool "IBM System z10" 332 select HAVE_MARCH_Z10_FEATURES 333 depends on $(cc-option,-march=z10) 334 help 335 Select this to enable optimizations for IBM System z10 (2097 and 2098 336 series). This is the oldest machine generation currently supported. 337 338config MARCH_Z196 339 bool "IBM zEnterprise 114 and 196" 340 select HAVE_MARCH_Z196_FEATURES 341 depends on $(cc-option,-march=z196) 342 help 343 Select this to enable optimizations for IBM zEnterprise 114 and 196 344 (2818 and 2817 series). The kernel will be slightly faster but will 345 not work on older machines. 346 347config MARCH_ZEC12 348 bool "IBM zBC12 and zEC12" 349 select HAVE_MARCH_ZEC12_FEATURES 350 depends on $(cc-option,-march=zEC12) 351 help 352 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 353 2827 series). The kernel will be slightly faster but will not work on 354 older machines. 355 356config MARCH_Z13 357 bool "IBM z13s and z13" 358 select HAVE_MARCH_Z13_FEATURES 359 depends on $(cc-option,-march=z13) 360 help 361 Select this to enable optimizations for IBM z13s and z13 (2965 and 362 2964 series). The kernel will be slightly faster but will not work on 363 older machines. 364 365config MARCH_Z14 366 bool "IBM z14 ZR1 and z14" 367 select HAVE_MARCH_Z14_FEATURES 368 depends on $(cc-option,-march=z14) 369 help 370 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 371 and 3906 series). The kernel will be slightly faster but will not 372 work on older machines. 373 374config MARCH_Z15 375 bool "IBM z15" 376 select HAVE_MARCH_Z15_FEATURES 377 depends on $(cc-option,-march=z15) 378 help 379 Select this to enable optimizations for IBM z15 (8562 380 and 8561 series). The kernel will be slightly faster but will not 381 work on older machines. 382 383config MARCH_Z16 384 bool "IBM z16" 385 select HAVE_MARCH_Z16_FEATURES 386 depends on $(cc-option,-march=z16) 387 help 388 Select this to enable optimizations for IBM z16 (3931 and 389 3932 series). 390 391endchoice 392 393config MARCH_Z10_TUNE 394 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 395 396config MARCH_Z196_TUNE 397 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 398 399config MARCH_ZEC12_TUNE 400 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 401 402config MARCH_Z13_TUNE 403 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 404 405config MARCH_Z14_TUNE 406 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 407 408config MARCH_Z15_TUNE 409 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 410 411config MARCH_Z16_TUNE 412 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 413 414choice 415 prompt "Tune code generation" 416 default TUNE_DEFAULT 417 help 418 Cause the compiler to tune (-mtune) the generated code for a machine. 419 This will make the code run faster on the selected machine but 420 somewhat slower on other machines. 421 This option only changes how the compiler emits instructions, not the 422 selection of instructions itself, so the resulting kernel will run on 423 all other machines. 424 425config TUNE_DEFAULT 426 bool "Default" 427 help 428 Tune the generated code for the target processor for which the kernel 429 will be compiled. 430 431config TUNE_Z10 432 bool "IBM System z10" 433 434config TUNE_Z196 435 bool "IBM zEnterprise 114 and 196" 436 depends on $(cc-option,-mtune=z196) 437 438config TUNE_ZEC12 439 bool "IBM zBC12 and zEC12" 440 depends on $(cc-option,-mtune=zEC12) 441 442config TUNE_Z13 443 bool "IBM z13s and z13" 444 depends on $(cc-option,-mtune=z13) 445 446config TUNE_Z14 447 bool "IBM z14 ZR1 and z14" 448 depends on $(cc-option,-mtune=z14) 449 450config TUNE_Z15 451 bool "IBM z15" 452 depends on $(cc-option,-mtune=z15) 453 454config TUNE_Z16 455 bool "IBM z16" 456 depends on $(cc-option,-mtune=z16) 457 458endchoice 459 460config 64BIT 461 def_bool y 462 463config COMMAND_LINE_SIZE 464 int "Maximum size of kernel command line" 465 default 4096 466 range 896 1048576 467 help 468 This allows you to specify the maximum length of the kernel command 469 line. 470 471config COMPAT 472 def_bool n 473 prompt "Kernel support for 31 bit emulation" 474 select ARCH_WANT_OLD_COMPAT_IPC 475 select COMPAT_OLD_SIGACTION 476 select HAVE_UID16 477 depends on MULTIUSER 478 depends on !CC_IS_CLANG && !LD_IS_LLD 479 help 480 Select this option if you want to enable your system kernel to 481 handle system-calls from ELF binaries for 31 bit ESA. This option 482 (and some other stuff like libraries and such) is needed for 483 executing 31 bit applications. 484 485 If unsure say N. 486 487config SMP 488 def_bool y 489 490config NR_CPUS 491 int "Maximum number of CPUs (2-512)" 492 range 2 512 493 default "64" 494 help 495 This allows you to specify the maximum number of CPUs which this 496 kernel will support. The maximum supported value is 512 and the 497 minimum value which makes sense is 2. 498 499 This is purely to save memory - each supported CPU adds 500 approximately sixteen kilobytes to the kernel image. 501 502config HOTPLUG_CPU 503 def_bool y 504 505config NUMA 506 bool "NUMA support" 507 depends on SCHED_TOPOLOGY 508 default n 509 help 510 Enable NUMA support 511 512 This option adds NUMA support to the kernel. 513 514config NODES_SHIFT 515 int 516 depends on NUMA 517 default "1" 518 519config SCHED_SMT 520 def_bool n 521 522config SCHED_MC 523 def_bool n 524 525config SCHED_TOPOLOGY 526 def_bool y 527 prompt "Topology scheduler support" 528 select SCHED_SMT 529 select SCHED_MC 530 help 531 Topology scheduler support improves the CPU scheduler's decision 532 making when dealing with machines that have multi-threading, 533 multiple cores or multiple books. 534 535config SCHED_TOPOLOGY_VERTICAL 536 def_bool y 537 bool "Use vertical CPU polarization by default" 538 depends on SCHED_TOPOLOGY 539 help 540 Use vertical CPU polarization by default if available. 541 The default CPU polarization is horizontal. 542 543config HIPERDISPATCH_ON 544 def_bool y 545 bool "Use hiperdispatch on vertical polarization by default" 546 depends on SCHED_TOPOLOGY 547 depends on PROC_SYSCTL 548 help 549 Hiperdispatch aims to improve the CPU scheduler's decision 550 making when using vertical polarization by adjusting CPU 551 capacities dynamically. Set this option to use hiperdispatch 552 on vertical polarization by default. This can be overwritten 553 by sysctl's s390.hiperdispatch attribute later on. 554 555source "kernel/Kconfig.hz" 556 557config CERT_STORE 558 bool "Get user certificates via DIAG320" 559 depends on KEYS 560 select CRYPTO_LIB_SHA256 561 help 562 Enable this option if you want to access user-provided secure boot 563 certificates via DIAG 0x320. 564 565 These certificates will be made available via the keyring named 566 'cert_store'. 567 568config KERNEL_NOBP 569 def_bool n 570 prompt "Enable modified branch prediction for the kernel by default" 571 help 572 If this option is selected the kernel will switch to a modified 573 branch prediction mode if the firmware interface is available. 574 The modified branch prediction mode improves the behaviour in 575 regard to speculative execution. 576 577 With the option enabled the kernel parameter "nobp=0" or "nospec" 578 can be used to run the kernel in the normal branch prediction mode. 579 580 With the option disabled the modified branch prediction mode is 581 enabled with the "nobp=1" kernel parameter. 582 583 If unsure, say N. 584 585config EXPOLINE 586 def_bool n 587 depends on $(cc-option,-mindirect-branch=thunk) 588 prompt "Avoid speculative indirect branches in the kernel" 589 help 590 Compile the kernel with the expoline compiler options to guard 591 against kernel-to-user data leaks by avoiding speculative indirect 592 branches. 593 Requires a compiler with -mindirect-branch=thunk support for full 594 protection. The kernel may run slower. 595 596 If unsure, say N. 597 598config EXPOLINE_EXTERN 599 def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \ 600 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 601 help 602 Generate expolines as external functions if the compiler supports it. 603 This option is required for some tooling like kpatch, if expolines 604 are enabled. The kernel is compiled with 605 -mindirect-branch=thunk-extern, which requires a newer compiler. 606 607choice 608 prompt "Expoline default" 609 depends on EXPOLINE 610 default EXPOLINE_FULL 611 612config EXPOLINE_OFF 613 bool "spectre_v2=off" 614 615config EXPOLINE_AUTO 616 bool "spectre_v2=auto" 617 618config EXPOLINE_FULL 619 bool "spectre_v2=on" 620 621endchoice 622 623config RELOCATABLE 624 def_bool y 625 help 626 This builds a kernel image that retains relocation information 627 so it can be loaded at an arbitrary address. 628 The relocations make the kernel image about 15% larger (compressed 629 10%), but are discarded at runtime. 630 Note: this option exists only for documentation purposes, please do 631 not remove it. 632 633config RANDOMIZE_BASE 634 bool "Randomize the address of the kernel image (KASLR)" 635 default y 636 help 637 In support of Kernel Address Space Layout Randomization (KASLR), 638 this randomizes the address at which the kernel image is loaded, 639 as a security feature that deters exploit attempts relying on 640 knowledge of the location of kernel internals. 641 642config RANDOMIZE_IDENTITY_BASE 643 bool "Randomize the address of the identity mapping base" 644 depends on RANDOMIZE_BASE 645 default DEBUG_VM 646 help 647 The identity mapping base address is pinned to zero by default. 648 Allow randomization of that base to expose otherwise missed 649 notion of physical and virtual addresses of data structures. 650 That does not have any impact on the base address at which the 651 kernel image is loaded. 652 653 If unsure, say N 654 655config KERNEL_IMAGE_BASE 656 hex "Kernel image base address" 657 range 0x100000 0x1FFFFFE0000000 if !KASAN 658 range 0x100000 0x1BFFFFE0000000 if KASAN 659 default 0x3FFE0000000 if !KASAN 660 default 0x7FFFE0000000 if KASAN 661 help 662 This is the address at which the kernel image is loaded in case 663 Kernel Address Space Layout Randomization (KASLR) is disabled. 664 665 In case the Protected virtualization guest support is enabled the 666 Ultravisor imposes a virtual address limit. If the value of this 667 option leads to the kernel image exceeding the Ultravisor limit, 668 this option is ignored and the image is loaded below the limit. 669 670 If the value of this option leads to the kernel image overlapping 671 the virtual memory where other data structures are located, this 672 option is ignored and the image is loaded above the structures. 673 674endmenu 675 676menu "Memory setup" 677 678config ARCH_SPARSEMEM_ENABLE 679 def_bool y 680 select SPARSEMEM_VMEMMAP_ENABLE 681 select SPARSEMEM_VMEMMAP 682 683config ARCH_SPARSEMEM_DEFAULT 684 def_bool y 685 686config MAX_PHYSMEM_BITS 687 int "Maximum size of supported physical memory in bits (42-53)" 688 range 42 53 689 default "46" 690 help 691 This option specifies the maximum supported size of physical memory 692 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 693 Increasing the number of bits also increases the kernel image size. 694 By default 46 bits (64TB) are supported. 695 696endmenu 697 698menu "I/O subsystem" 699 700config QDIO 701 def_tristate y 702 prompt "QDIO support" 703 help 704 This driver provides the Queued Direct I/O base support for 705 IBM System z. 706 707 To compile this driver as a module, choose M here: the 708 module will be called qdio. 709 710 If unsure, say Y. 711 712if PCI 713 714config PCI_NR_FUNCTIONS 715 int "Maximum number of PCI functions (1-4096)" 716 range 1 4096 717 default "512" 718 help 719 This allows you to specify the maximum number of PCI functions which 720 this kernel will support. 721 722endif # PCI 723 724config HAS_IOMEM 725 def_bool PCI 726 727config CHSC_SCH 728 def_tristate m 729 prompt "Support for CHSC subchannels" 730 help 731 This driver allows usage of CHSC subchannels. A CHSC subchannel 732 is usually present on LPAR only. 733 The driver creates a device /dev/chsc, which may be used to 734 obtain I/O configuration information about the machine and 735 to issue asynchronous chsc commands (DANGEROUS). 736 You will usually only want to use this interface on a special 737 LPAR designated for system management. 738 739 To compile this driver as a module, choose M here: the 740 module will be called chsc_sch. 741 742 If unsure, say N. 743 744config SCM_BUS 745 def_bool y 746 prompt "SCM bus driver" 747 help 748 Bus driver for Storage Class Memory. 749 750config EADM_SCH 751 def_tristate m 752 prompt "Support for EADM subchannels" 753 depends on SCM_BUS 754 help 755 This driver allows usage of EADM subchannels. EADM subchannels act 756 as a communication vehicle for SCM increments. 757 758 To compile this driver as a module, choose M here: the 759 module will be called eadm_sch. 760 761config AP 762 def_tristate y 763 prompt "Support for Adjunct Processors (ap)" 764 help 765 This driver allows usage to Adjunct Processor (AP) devices via 766 the ap bus, cards and queues. Supported Adjunct Processors are 767 the CryptoExpress Cards (CEX). 768 769 To compile this driver as a module, choose M here: the 770 module will be called ap. 771 772 If unsure, say Y (default). 773 774config AP_DEBUG 775 def_bool n 776 prompt "Enable debug features for Adjunct Processor (ap) devices" 777 depends on AP 778 help 779 Say 'Y' here to enable some additional debug features for Adjunct 780 Processor (ap) devices. 781 782 There will be some more sysfs attributes displayed for ap queues. 783 784 Do not enable on production level kernel build. 785 786 If unsure, say N. 787 788config VFIO_CCW 789 def_tristate n 790 prompt "Support for VFIO-CCW subchannels" 791 depends on VFIO 792 select VFIO_MDEV 793 help 794 This driver allows usage of I/O subchannels via VFIO-CCW. 795 796 To compile this driver as a module, choose M here: the 797 module will be called vfio_ccw. 798 799config VFIO_AP 800 def_tristate n 801 prompt "VFIO support for AP devices" 802 depends on KVM 803 depends on VFIO 804 depends on AP 805 select VFIO_MDEV 806 help 807 This driver grants access to Adjunct Processor (AP) devices 808 via the VFIO mediated device interface. 809 810 To compile this driver as a module, choose M here: the module 811 will be called vfio_ap. 812 813endmenu 814 815config CCW 816 def_bool y 817 818config HAVE_PNETID 819 tristate 820 default (SMC || CCWGROUP) 821 822menu "Virtualization" 823 824config PFAULT 825 def_bool y 826 prompt "Pseudo page fault support" 827 help 828 Select this option, if you want to use PFAULT pseudo page fault 829 handling under VM. If running native or in LPAR, this option 830 has no effect. If your VM does not support PFAULT, PAGEEX 831 pseudo page fault handling will be used. 832 Note that VM 4.2 supports PFAULT but has a bug in its 833 implementation that causes some problems. 834 Everybody who wants to run Linux under VM != VM4.2 should select 835 this option. 836 837config CMM 838 def_tristate n 839 prompt "Cooperative memory management" 840 help 841 Select this option, if you want to enable the kernel interface 842 to reduce the memory size of the system. This is accomplished 843 by allocating pages of memory and put them "on hold". This only 844 makes sense for a system running under VM where the unused pages 845 will be reused by VM for other guest systems. The interface 846 allows an external monitor to balance memory of many systems. 847 Everybody who wants to run Linux under VM should select this 848 option. 849 850config CMM_IUCV 851 def_bool y 852 prompt "IUCV special message interface to cooperative memory management" 853 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 854 help 855 Select this option to enable the special message interface to 856 the cooperative memory management. 857 858config APPLDATA_BASE 859 def_bool n 860 prompt "Linux - VM Monitor Stream, base infrastructure" 861 depends on PROC_SYSCTL 862 help 863 This provides a kernel interface for creating and updating z/VM APPLDATA 864 monitor records. The monitor records are updated at certain time 865 intervals, once the timer is started. 866 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 867 i.e. enables or disables monitoring on the Linux side. 868 A custom interval value (in seconds) can be written to 869 /proc/appldata/interval. 870 871 Defaults are 60 seconds interval and timer off. 872 The /proc entries can also be read from, showing the current settings. 873 874config APPLDATA_MEM 875 def_tristate m 876 prompt "Monitor memory management statistics" 877 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 878 help 879 This provides memory management related data to the Linux - VM Monitor 880 Stream, like paging/swapping rate, memory utilisation, etc. 881 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 882 APPLDATA monitor record, i.e. enables or disables monitoring this record 883 on the z/VM side. 884 885 Default is disabled. 886 The /proc entry can also be read from, showing the current settings. 887 888 This can also be compiled as a module, which will be called 889 appldata_mem.o. 890 891config APPLDATA_OS 892 def_tristate m 893 prompt "Monitor OS statistics" 894 depends on APPLDATA_BASE 895 help 896 This provides OS related data to the Linux - VM Monitor Stream, like 897 CPU utilisation, etc. 898 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 899 APPLDATA monitor record, i.e. enables or disables monitoring this record 900 on the z/VM side. 901 902 Default is disabled. 903 This can also be compiled as a module, which will be called 904 appldata_os.o. 905 906config APPLDATA_NET_SUM 907 def_tristate m 908 prompt "Monitor overall network statistics" 909 depends on APPLDATA_BASE && NET 910 help 911 This provides network related data to the Linux - VM Monitor Stream, 912 currently there is only a total sum of network I/O statistics, no 913 per-interface data. 914 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 915 APPLDATA monitor record, i.e. enables or disables monitoring this record 916 on the z/VM side. 917 918 Default is disabled. 919 This can also be compiled as a module, which will be called 920 appldata_net_sum.o. 921 922config S390_HYPFS 923 def_bool y 924 prompt "s390 hypervisor information" 925 help 926 This provides several binary files at (debugfs)/s390_hypfs/ to 927 provide accounting information in an s390 hypervisor environment. 928 929config S390_HYPFS_FS 930 def_bool n 931 prompt "s390 hypervisor file system support" 932 select SYS_HYPERVISOR 933 depends on S390_HYPFS 934 help 935 This is a virtual file system intended to provide accounting 936 information in an s390 hypervisor environment. This file system 937 is deprecated and should not be used. 938 939 Say N if you are unsure. 940 941source "arch/s390/kvm/Kconfig" 942 943config S390_GUEST 944 def_bool y 945 prompt "s390 support for virtio devices" 946 select TTY 947 select VIRTUALIZATION 948 select VIRTIO 949 help 950 Enabling this option adds support for virtio based paravirtual device 951 drivers on s390. 952 953 Select this option if you want to run the kernel as a guest under 954 the KVM hypervisor. 955 956endmenu 957 958config S390_MODULES_SANITY_TEST_HELPERS 959 def_bool n 960 961menu "Selftests" 962 963config S390_UNWIND_SELFTEST 964 def_tristate n 965 depends on KUNIT 966 default KUNIT_ALL_TESTS 967 prompt "Test unwind functions" 968 help 969 This option enables s390 specific stack unwinder testing kernel 970 module. This option is not useful for distributions or general 971 kernels, but only for kernel developers working on architecture code. 972 973 Say N if you are unsure. 974 975config S390_KPROBES_SANITY_TEST 976 def_tristate n 977 prompt "Enable s390 specific kprobes tests" 978 depends on KPROBES 979 depends on KUNIT 980 help 981 This option enables an s390 specific kprobes test module. This option 982 is not useful for distributions or general kernels, but only for kernel 983 developers working on architecture code. 984 985 Say N if you are unsure. 986 987config S390_MODULES_SANITY_TEST 988 def_tristate n 989 depends on KUNIT 990 default KUNIT_ALL_TESTS 991 prompt "Enable s390 specific modules tests" 992 select S390_MODULES_SANITY_TEST_HELPERS 993 help 994 This option enables an s390 specific modules test. This option is 995 not useful for distributions or general kernels, but only for 996 kernel developers working on architecture code. 997 998 Say N if you are unsure. 999endmenu 1000