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 ARCH_SUPPORTS_UPROBES 45 def_bool y 46 47config KASAN_SHADOW_OFFSET 48 hex 49 depends on KASAN 50 default 0x1C000000000000 51 52config CC_ASM_FLAG_OUTPUT_BROKEN 53 def_bool CC_IS_GCC && GCC_VERSION < 140200 54 help 55 GCC versions before 14.2.0 may die with an internal 56 compiler error in some configurations if flag output 57 operands are used within inline assemblies. 58 59config CC_HAS_ASM_AOR_FORMAT_FLAGS 60 def_bool !(CC_IS_CLANG && CLANG_VERSION < 190100) 61 help 62 Clang versions before 19.1.0 do not support A, 63 O, and R inline assembly format flags. 64 65config S390 66 def_bool y 67 # 68 # Note: keep this list sorted alphabetically 69 # 70 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 71 select ALTERNATE_USER_ADDRESS_SPACE 72 select ARCH_32BIT_USTAT_F_TINODE 73 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 74 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 75 select ARCH_ENABLE_MEMORY_HOTREMOVE 76 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 77 select ARCH_HAS_CPU_FINALIZE_INIT 78 select ARCH_HAS_CRC32 79 select ARCH_HAS_CURRENT_STACK_POINTER 80 select ARCH_HAS_DEBUG_VIRTUAL 81 select ARCH_HAS_DEBUG_VM_PGTABLE 82 select ARCH_HAS_DEBUG_WX 83 select ARCH_HAS_DEVMEM_IS_ALLOWED 84 select ARCH_HAS_DMA_OPS if PCI 85 select ARCH_HAS_ELF_RANDOMIZE 86 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 87 select ARCH_HAS_FORTIFY_SOURCE 88 select ARCH_HAS_GCOV_PROFILE_ALL 89 select ARCH_HAS_GIGANTIC_PAGE 90 select ARCH_HAS_KCOV 91 select ARCH_HAS_MEMBARRIER_SYNC_CORE 92 select ARCH_HAS_MEM_ENCRYPT 93 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 94 select ARCH_HAS_PREEMPT_LAZY 95 select ARCH_HAS_PTDUMP 96 select ARCH_HAS_PTE_SPECIAL 97 select ARCH_HAS_SCALED_CPUTIME 98 select ARCH_HAS_SET_DIRECT_MAP 99 select ARCH_HAS_SET_MEMORY 100 select ARCH_HAS_STRICT_KERNEL_RWX 101 select ARCH_HAS_STRICT_MODULE_RWX 102 select ARCH_HAS_SYSCALL_WRAPPER 103 select ARCH_HAS_UBSAN 104 select ARCH_HAS_VDSO_TIME_DATA 105 select ARCH_HAVE_NMI_SAFE_CMPXCHG 106 select ARCH_INLINE_READ_LOCK 107 select ARCH_INLINE_READ_LOCK_BH 108 select ARCH_INLINE_READ_LOCK_IRQ 109 select ARCH_INLINE_READ_LOCK_IRQSAVE 110 select ARCH_INLINE_READ_TRYLOCK 111 select ARCH_INLINE_READ_UNLOCK 112 select ARCH_INLINE_READ_UNLOCK_BH 113 select ARCH_INLINE_READ_UNLOCK_IRQ 114 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 115 select ARCH_INLINE_SPIN_LOCK 116 select ARCH_INLINE_SPIN_LOCK_BH 117 select ARCH_INLINE_SPIN_LOCK_IRQ 118 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 119 select ARCH_INLINE_SPIN_TRYLOCK 120 select ARCH_INLINE_SPIN_TRYLOCK_BH 121 select ARCH_INLINE_SPIN_UNLOCK 122 select ARCH_INLINE_SPIN_UNLOCK_BH 123 select ARCH_INLINE_SPIN_UNLOCK_IRQ 124 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 125 select ARCH_INLINE_WRITE_LOCK 126 select ARCH_INLINE_WRITE_LOCK_BH 127 select ARCH_INLINE_WRITE_LOCK_IRQ 128 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 129 select ARCH_INLINE_WRITE_TRYLOCK 130 select ARCH_INLINE_WRITE_UNLOCK 131 select ARCH_INLINE_WRITE_UNLOCK_BH 132 select ARCH_INLINE_WRITE_UNLOCK_IRQ 133 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 134 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE 135 select ARCH_STACKWALK 136 select ARCH_SUPPORTS_ATOMIC_RMW 137 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 138 select ARCH_SUPPORTS_HUGETLBFS 139 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG 140 select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS 141 select ARCH_SUPPORTS_NUMA_BALANCING 142 select ARCH_SUPPORTS_PER_VMA_LOCK 143 select ARCH_USE_BUILTIN_BSWAP 144 select ARCH_USE_CMPXCHG_LOCKREF 145 select ARCH_USE_SYM_ANNOTATIONS 146 select ARCH_WANTS_NO_INSTR 147 select ARCH_WANT_DEFAULT_BPF_JIT 148 select ARCH_WANT_IPC_PARSE_VERSION 149 select ARCH_WANT_KERNEL_PMD_MKWRITE 150 select ARCH_WANT_LD_ORPHAN_WARN 151 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 152 select BUILDTIME_TABLE_SORT 153 select CLONE_BACKWARDS2 154 select DCACHE_WORD_ACCESS if !KMSAN 155 select DYNAMIC_FTRACE if FUNCTION_TRACER 156 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 157 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 158 select GENERIC_ALLOCATOR 159 select GENERIC_CPU_DEVICES 160 select GENERIC_CPU_AUTOPROBE 161 select GENERIC_CPU_VULNERABILITIES 162 select GENERIC_ENTRY 163 select GENERIC_GETTIMEOFDAY 164 select GENERIC_SMP_IDLE_THREAD 165 select GENERIC_TIME_VSYSCALL 166 select GENERIC_VDSO_DATA_STORE 167 select GENERIC_VDSO_TIME_NS 168 select GENERIC_IOREMAP if PCI 169 select HAVE_ALIGNED_STRUCT_PAGE 170 select HAVE_ARCH_AUDITSYSCALL 171 select HAVE_ARCH_JUMP_LABEL 172 select HAVE_ARCH_JUMP_LABEL_RELATIVE 173 select HAVE_ARCH_KASAN 174 select HAVE_ARCH_KASAN_VMALLOC 175 select HAVE_ARCH_KCSAN 176 select HAVE_ARCH_KMSAN 177 select HAVE_ARCH_KFENCE 178 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 179 select HAVE_ARCH_SECCOMP_FILTER 180 select HAVE_ARCH_SOFT_DIRTY 181 select HAVE_ARCH_STACKLEAK 182 select HAVE_ARCH_TRACEHOOK 183 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 184 select HAVE_ARCH_VMAP_STACK 185 select HAVE_ASM_MODVERSIONS 186 select HAVE_BUILDTIME_MCOUNT_SORT 187 select HAVE_CMPXCHG_DOUBLE 188 select HAVE_CMPXCHG_LOCAL 189 select HAVE_DEBUG_KMEMLEAK 190 select HAVE_DMA_CONTIGUOUS 191 select HAVE_DYNAMIC_FTRACE 192 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 193 select HAVE_FTRACE_REGS_HAVING_PT_REGS 194 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 195 select HAVE_DYNAMIC_FTRACE_WITH_REGS 196 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 197 select HAVE_EFFICIENT_UNALIGNED_ACCESS 198 select HAVE_GUP_FAST 199 select HAVE_FENTRY 200 select HAVE_FTRACE_GRAPH_FUNC 201 select HAVE_FTRACE_MCOUNT_RECORD 202 select HAVE_FUNCTION_ARG_ACCESS_API 203 select HAVE_FUNCTION_ERROR_INJECTION 204 select HAVE_FUNCTION_GRAPH_FREGS 205 select HAVE_FUNCTION_GRAPH_TRACER 206 select HAVE_FUNCTION_TRACER 207 select HAVE_GCC_PLUGINS 208 select HAVE_GENERIC_VDSO 209 select HAVE_IOREMAP_PROT if PCI 210 select HAVE_KERNEL_BZIP2 211 select HAVE_KERNEL_GZIP 212 select HAVE_KERNEL_LZ4 213 select HAVE_KERNEL_LZMA 214 select HAVE_KERNEL_LZO 215 select HAVE_KERNEL_UNCOMPRESSED 216 select HAVE_KERNEL_XZ 217 select HAVE_KERNEL_ZSTD 218 select HAVE_KPROBES 219 select HAVE_KPROBES_ON_FTRACE 220 select HAVE_KRETPROBES 221 select HAVE_LIVEPATCH 222 select HAVE_MEMBLOCK_PHYS_MAP 223 select HAVE_MOD_ARCH_SPECIFIC 224 select HAVE_NMI 225 select HAVE_NOP_MCOUNT 226 select HAVE_PAGE_SIZE_4KB 227 select HAVE_PCI 228 select HAVE_PERF_EVENTS 229 select HAVE_PERF_REGS 230 select HAVE_PERF_USER_STACK_DUMP 231 select HAVE_PREEMPT_DYNAMIC_KEY 232 select HAVE_REGS_AND_STACK_ACCESS_API 233 select HAVE_RELIABLE_STACKTRACE 234 select HAVE_RETHOOK 235 select HAVE_RSEQ 236 select HAVE_SAMPLE_FTRACE_DIRECT 237 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 238 select HAVE_SETUP_PER_CPU_AREA 239 select HAVE_SOFTIRQ_ON_OWN_STACK 240 select HAVE_SYSCALL_TRACEPOINTS 241 select HAVE_VIRT_CPU_ACCOUNTING 242 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 243 select HOTPLUG_SMT 244 select IOMMU_HELPER if PCI 245 select IOMMU_SUPPORT if PCI 246 select KASAN_VMALLOC if KASAN 247 select LOCK_MM_AND_FIND_VMA 248 select MMU_GATHER_MERGE_VMAS 249 select MMU_GATHER_NO_GATHER 250 select MMU_GATHER_RCU_TABLE_FREE 251 select MODULES_USE_ELF_RELA 252 select NEED_DMA_MAP_STATE if PCI 253 select NEED_PER_CPU_EMBED_FIRST_CHUNK 254 select NEED_PROC_VMCORE_DEVICE_RAM if PROC_VMCORE 255 select NEED_SG_DMA_LENGTH if PCI 256 select OLD_SIGACTION 257 select OLD_SIGSUSPEND3 258 select PCI_DOMAINS if PCI 259 select PCI_MSI if PCI 260 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 261 select PCI_QUIRKS if PCI 262 select SPARSE_IRQ 263 select SWIOTLB 264 select SYSCTL_EXCEPTION_TRACE 265 select THREAD_INFO_IN_TASK 266 select TRACE_IRQFLAGS_SUPPORT 267 select TTY 268 select USER_STACKTRACE_SUPPORT 269 select VDSO_GETRANDOM 270 select VIRT_CPU_ACCOUNTING 271 select VMAP_STACK 272 select ZONE_DMA 273 # Note: keep the above list sorted alphabetically 274 275config SCHED_OMIT_FRAME_POINTER 276 def_bool y 277 278config PGTABLE_LEVELS 279 int 280 default 5 281 282source "kernel/livepatch/Kconfig" 283 284config ARCH_SUPPORTS_KEXEC 285 def_bool y 286 287config ARCH_SUPPORTS_KEXEC_FILE 288 def_bool y 289 290config ARCH_SUPPORTS_KEXEC_SIG 291 def_bool MODULE_SIG_FORMAT 292 293config ARCH_SUPPORTS_KEXEC_PURGATORY 294 def_bool y 295 296config ARCH_SUPPORTS_CRASH_DUMP 297 def_bool y 298 help 299 Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this. 300 This option also enables s390 zfcpdump. 301 See also <file:Documentation/arch/s390/zfcpdump.rst> 302 303config ARCH_DEFAULT_CRASH_DUMP 304 def_bool y 305 306menu "Processor type and features" 307 308config HAVE_MARCH_Z10_FEATURES 309 def_bool n 310 311config HAVE_MARCH_Z196_FEATURES 312 def_bool n 313 select HAVE_MARCH_Z10_FEATURES 314 315config HAVE_MARCH_ZEC12_FEATURES 316 def_bool n 317 select HAVE_MARCH_Z196_FEATURES 318 319config HAVE_MARCH_Z13_FEATURES 320 def_bool n 321 select HAVE_MARCH_ZEC12_FEATURES 322 323config HAVE_MARCH_Z14_FEATURES 324 def_bool n 325 select HAVE_MARCH_Z13_FEATURES 326 327config HAVE_MARCH_Z15_FEATURES 328 def_bool n 329 select HAVE_MARCH_Z14_FEATURES 330 331config HAVE_MARCH_Z16_FEATURES 332 def_bool n 333 select HAVE_MARCH_Z15_FEATURES 334 335choice 336 prompt "Processor type" 337 default MARCH_Z196 338 339config MARCH_Z10 340 bool "IBM System z10" 341 select HAVE_MARCH_Z10_FEATURES 342 depends on $(cc-option,-march=z10) 343 help 344 Select this to enable optimizations for IBM System z10 (2097 and 2098 345 series). This is the oldest machine generation currently supported. 346 347config MARCH_Z196 348 bool "IBM zEnterprise 114 and 196" 349 select HAVE_MARCH_Z196_FEATURES 350 depends on $(cc-option,-march=z196) 351 help 352 Select this to enable optimizations for IBM zEnterprise 114 and 196 353 (2818 and 2817 series). The kernel will be slightly faster but will 354 not work on older machines. 355 356config MARCH_ZEC12 357 bool "IBM zBC12 and zEC12" 358 select HAVE_MARCH_ZEC12_FEATURES 359 depends on $(cc-option,-march=zEC12) 360 help 361 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 362 2827 series). The kernel will be slightly faster but will not work on 363 older machines. 364 365config MARCH_Z13 366 bool "IBM z13s and z13" 367 select HAVE_MARCH_Z13_FEATURES 368 depends on $(cc-option,-march=z13) 369 help 370 Select this to enable optimizations for IBM z13s and z13 (2965 and 371 2964 series). The kernel will be slightly faster but will not work on 372 older machines. 373 374config MARCH_Z14 375 bool "IBM z14 ZR1 and z14" 376 select HAVE_MARCH_Z14_FEATURES 377 depends on $(cc-option,-march=z14) 378 help 379 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 380 and 3906 series). The kernel will be slightly faster but will not 381 work on older machines. 382 383config MARCH_Z15 384 bool "IBM z15" 385 select HAVE_MARCH_Z15_FEATURES 386 depends on $(cc-option,-march=z15) 387 help 388 Select this to enable optimizations for IBM z15 (8562 389 and 8561 series). The kernel will be slightly faster but will not 390 work on older machines. 391 392config MARCH_Z16 393 bool "IBM z16" 394 select HAVE_MARCH_Z16_FEATURES 395 depends on $(cc-option,-march=z16) 396 help 397 Select this to enable optimizations for IBM z16 (3931 and 398 3932 series). 399 400endchoice 401 402config MARCH_Z10_TUNE 403 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 404 405config MARCH_Z196_TUNE 406 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 407 408config MARCH_ZEC12_TUNE 409 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 410 411config MARCH_Z13_TUNE 412 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 413 414config MARCH_Z14_TUNE 415 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 416 417config MARCH_Z15_TUNE 418 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 419 420config MARCH_Z16_TUNE 421 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 422 423choice 424 prompt "Tune code generation" 425 default TUNE_DEFAULT 426 help 427 Cause the compiler to tune (-mtune) the generated code for a machine. 428 This will make the code run faster on the selected machine but 429 somewhat slower on other machines. 430 This option only changes how the compiler emits instructions, not the 431 selection of instructions itself, so the resulting kernel will run on 432 all other machines. 433 434config TUNE_DEFAULT 435 bool "Default" 436 help 437 Tune the generated code for the target processor for which the kernel 438 will be compiled. 439 440config TUNE_Z10 441 bool "IBM System z10" 442 443config TUNE_Z196 444 bool "IBM zEnterprise 114 and 196" 445 depends on $(cc-option,-mtune=z196) 446 447config TUNE_ZEC12 448 bool "IBM zBC12 and zEC12" 449 depends on $(cc-option,-mtune=zEC12) 450 451config TUNE_Z13 452 bool "IBM z13s and z13" 453 depends on $(cc-option,-mtune=z13) 454 455config TUNE_Z14 456 bool "IBM z14 ZR1 and z14" 457 depends on $(cc-option,-mtune=z14) 458 459config TUNE_Z15 460 bool "IBM z15" 461 depends on $(cc-option,-mtune=z15) 462 463config TUNE_Z16 464 bool "IBM z16" 465 depends on $(cc-option,-mtune=z16) 466 467endchoice 468 469config 64BIT 470 def_bool y 471 472config COMMAND_LINE_SIZE 473 int "Maximum size of kernel command line" 474 default 4096 475 range 896 1048576 476 help 477 This allows you to specify the maximum length of the kernel command 478 line. 479 480config COMPAT 481 def_bool n 482 prompt "Kernel support for 31 bit emulation" 483 select ARCH_WANT_OLD_COMPAT_IPC 484 select COMPAT_OLD_SIGACTION 485 select HAVE_UID16 486 depends on MULTIUSER 487 depends on !CC_IS_CLANG && !LD_IS_LLD 488 help 489 Select this option if you want to enable your system kernel to 490 handle system-calls from ELF binaries for 31 bit ESA. This option 491 (and some other stuff like libraries and such) is needed for 492 executing 31 bit applications. 493 494 If unsure say N. 495 496config SMP 497 def_bool y 498 499config NR_CPUS 500 int "Maximum number of CPUs (2-512)" 501 range 2 512 502 default "64" 503 help 504 This allows you to specify the maximum number of CPUs which this 505 kernel will support. The maximum supported value is 512 and the 506 minimum value which makes sense is 2. 507 508 This is purely to save memory - each supported CPU adds 509 approximately sixteen kilobytes to the kernel image. 510 511config HOTPLUG_CPU 512 def_bool y 513 514config NUMA 515 bool "NUMA support" 516 depends on SCHED_TOPOLOGY 517 default n 518 help 519 Enable NUMA support 520 521 This option adds NUMA support to the kernel. 522 523config NODES_SHIFT 524 int 525 depends on NUMA 526 default "1" 527 528config SCHED_SMT 529 def_bool n 530 531config SCHED_MC 532 def_bool n 533 534config SCHED_TOPOLOGY 535 def_bool y 536 prompt "Topology scheduler support" 537 select SCHED_SMT 538 select SCHED_MC 539 help 540 Topology scheduler support improves the CPU scheduler's decision 541 making when dealing with machines that have multi-threading, 542 multiple cores or multiple books. 543 544config SCHED_TOPOLOGY_VERTICAL 545 def_bool y 546 bool "Use vertical CPU polarization by default" 547 depends on SCHED_TOPOLOGY 548 help 549 Use vertical CPU polarization by default if available. 550 The default CPU polarization is horizontal. 551 552config HIPERDISPATCH_ON 553 def_bool y 554 bool "Use hiperdispatch on vertical polarization by default" 555 depends on SCHED_TOPOLOGY 556 depends on PROC_SYSCTL 557 help 558 Hiperdispatch aims to improve the CPU scheduler's decision 559 making when using vertical polarization by adjusting CPU 560 capacities dynamically. Set this option to use hiperdispatch 561 on vertical polarization by default. This can be overwritten 562 by sysctl's s390.hiperdispatch attribute later on. 563 564source "kernel/Kconfig.hz" 565 566config CERT_STORE 567 bool "Get user certificates via DIAG320" 568 depends on KEYS 569 select CRYPTO_LIB_SHA256 570 help 571 Enable this option if you want to access user-provided secure boot 572 certificates via DIAG 0x320. 573 574 These certificates will be made available via the keyring named 575 'cert_store'. 576 577config KERNEL_NOBP 578 def_bool n 579 prompt "Enable modified branch prediction for the kernel by default" 580 help 581 If this option is selected the kernel will switch to a modified 582 branch prediction mode if the firmware interface is available. 583 The modified branch prediction mode improves the behaviour in 584 regard to speculative execution. 585 586 With the option enabled the kernel parameter "nobp=0" or "nospec" 587 can be used to run the kernel in the normal branch prediction mode. 588 589 With the option disabled the modified branch prediction mode is 590 enabled with the "nobp=1" kernel parameter. 591 592 If unsure, say N. 593 594config EXPOLINE 595 def_bool n 596 depends on $(cc-option,-mindirect-branch=thunk) 597 prompt "Avoid speculative indirect branches in the kernel" 598 help 599 Compile the kernel with the expoline compiler options to guard 600 against kernel-to-user data leaks by avoiding speculative indirect 601 branches. 602 Requires a compiler with -mindirect-branch=thunk support for full 603 protection. The kernel may run slower. 604 605 If unsure, say N. 606 607config EXPOLINE_EXTERN 608 def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \ 609 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 610 help 611 Generate expolines as external functions if the compiler supports it. 612 This option is required for some tooling like kpatch, if expolines 613 are enabled. The kernel is compiled with 614 -mindirect-branch=thunk-extern, which requires a newer compiler. 615 616choice 617 prompt "Expoline default" 618 depends on EXPOLINE 619 default EXPOLINE_FULL 620 621config EXPOLINE_OFF 622 bool "spectre_v2=off" 623 624config EXPOLINE_AUTO 625 bool "spectre_v2=auto" 626 627config EXPOLINE_FULL 628 bool "spectre_v2=on" 629 630endchoice 631 632config RELOCATABLE 633 def_bool y 634 select ARCH_VMLINUX_NEEDS_RELOCS 635 help 636 This builds a kernel image that retains relocation information 637 so it can be loaded at an arbitrary address. 638 The relocations make the kernel image about 15% larger (compressed 639 10%), but are discarded at runtime. 640 Note: this option exists only for documentation purposes, please do 641 not remove it. 642 643config RANDOMIZE_BASE 644 bool "Randomize the address of the kernel image (KASLR)" 645 default y 646 help 647 In support of Kernel Address Space Layout Randomization (KASLR), 648 this randomizes the address at which the kernel image is loaded, 649 as a security feature that deters exploit attempts relying on 650 knowledge of the location of kernel internals. 651 652config RANDOMIZE_IDENTITY_BASE 653 bool "Randomize the address of the identity mapping base" 654 depends on RANDOMIZE_BASE 655 default DEBUG_VM 656 help 657 The identity mapping base address is pinned to zero by default. 658 Allow randomization of that base to expose otherwise missed 659 notion of physical and virtual addresses of data structures. 660 That does not have any impact on the base address at which the 661 kernel image is loaded. 662 663 If unsure, say N 664 665config KERNEL_IMAGE_BASE 666 hex "Kernel image base address" 667 range 0x100000 0x1FFFFFE0000000 if !KASAN 668 range 0x100000 0x1BFFFFE0000000 if KASAN 669 default 0x3FFE0000000 if !KASAN 670 default 0x7FFFE0000000 if KASAN 671 help 672 This is the address at which the kernel image is loaded in case 673 Kernel Address Space Layout Randomization (KASLR) is disabled. 674 675 In case the Protected virtualization guest support is enabled the 676 Ultravisor imposes a virtual address limit. If the value of this 677 option leads to the kernel image exceeding the Ultravisor limit, 678 this option is ignored and the image is loaded below the limit. 679 680 If the value of this option leads to the kernel image overlapping 681 the virtual memory where other data structures are located, this 682 option is ignored and the image is loaded above the structures. 683 684endmenu 685 686menu "Memory setup" 687 688config ARCH_SPARSEMEM_ENABLE 689 def_bool y 690 select SPARSEMEM_VMEMMAP_ENABLE 691 select SPARSEMEM_VMEMMAP 692 693config ARCH_SPARSEMEM_DEFAULT 694 def_bool y 695 696config MAX_PHYSMEM_BITS 697 int "Maximum size of supported physical memory in bits (42-53)" 698 range 42 53 699 default "46" 700 help 701 This option specifies the maximum supported size of physical memory 702 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 703 Increasing the number of bits also increases the kernel image size. 704 By default 46 bits (64TB) are supported. 705 706endmenu 707 708menu "I/O subsystem" 709 710config QDIO 711 def_tristate y 712 prompt "QDIO support" 713 help 714 This driver provides the Queued Direct I/O base support for 715 IBM System z. 716 717 To compile this driver as a module, choose M here: the 718 module will be called qdio. 719 720 If unsure, say Y. 721 722if PCI 723 724config PCI_NR_FUNCTIONS 725 int "Maximum number of PCI functions (1-4096)" 726 range 1 4096 727 default "512" 728 help 729 This allows you to specify the maximum number of PCI functions which 730 this kernel will support. 731 732endif # PCI 733 734config HAS_IOMEM 735 def_bool PCI 736 737config CHSC_SCH 738 def_tristate m 739 prompt "Support for CHSC subchannels" 740 help 741 This driver allows usage of CHSC subchannels. A CHSC subchannel 742 is usually present on LPAR only. 743 The driver creates a device /dev/chsc, which may be used to 744 obtain I/O configuration information about the machine and 745 to issue asynchronous chsc commands (DANGEROUS). 746 You will usually only want to use this interface on a special 747 LPAR designated for system management. 748 749 To compile this driver as a module, choose M here: the 750 module will be called chsc_sch. 751 752 If unsure, say N. 753 754config SCM_BUS 755 def_bool y 756 prompt "SCM bus driver" 757 help 758 Bus driver for Storage Class Memory. 759 760config EADM_SCH 761 def_tristate m 762 prompt "Support for EADM subchannels" 763 depends on SCM_BUS 764 help 765 This driver allows usage of EADM subchannels. EADM subchannels act 766 as a communication vehicle for SCM increments. 767 768 To compile this driver as a module, choose M here: the 769 module will be called eadm_sch. 770 771config AP 772 def_tristate y 773 prompt "Support for Adjunct Processors (ap)" 774 help 775 This driver allows usage to Adjunct Processor (AP) devices via 776 the ap bus, cards and queues. Supported Adjunct Processors are 777 the CryptoExpress Cards (CEX). 778 779 To compile this driver as a module, choose M here: the 780 module will be called ap. 781 782 If unsure, say Y (default). 783 784config AP_DEBUG 785 def_bool n 786 prompt "Enable debug features for Adjunct Processor (ap) devices" 787 depends on AP 788 help 789 Say 'Y' here to enable some additional debug features for Adjunct 790 Processor (ap) devices. 791 792 There will be some more sysfs attributes displayed for ap queues. 793 794 Do not enable on production level kernel build. 795 796 If unsure, say N. 797 798config VFIO_CCW 799 def_tristate n 800 prompt "Support for VFIO-CCW subchannels" 801 depends on VFIO 802 select VFIO_MDEV 803 help 804 This driver allows usage of I/O subchannels via VFIO-CCW. 805 806 To compile this driver as a module, choose M here: the 807 module will be called vfio_ccw. 808 809config VFIO_AP 810 def_tristate n 811 prompt "VFIO support for AP devices" 812 depends on KVM 813 depends on VFIO 814 depends on AP 815 select VFIO_MDEV 816 help 817 This driver grants access to Adjunct Processor (AP) devices 818 via the VFIO mediated device interface. 819 820 To compile this driver as a module, choose M here: the module 821 will be called vfio_ap. 822 823endmenu 824 825config CCW 826 def_bool y 827 828config HAVE_PNETID 829 tristate 830 default (SMC || CCWGROUP) 831 832menu "Virtualization" 833 834config PFAULT 835 def_bool y 836 prompt "Pseudo page fault support" 837 help 838 Select this option, if you want to use PFAULT pseudo page fault 839 handling under VM. If running native or in LPAR, this option 840 has no effect. If your VM does not support PFAULT, PAGEEX 841 pseudo page fault handling will be used. 842 Note that VM 4.2 supports PFAULT but has a bug in its 843 implementation that causes some problems. 844 Everybody who wants to run Linux under VM != VM4.2 should select 845 this option. 846 847config CMM 848 def_tristate n 849 prompt "Cooperative memory management" 850 help 851 Select this option, if you want to enable the kernel interface 852 to reduce the memory size of the system. This is accomplished 853 by allocating pages of memory and put them "on hold". This only 854 makes sense for a system running under VM where the unused pages 855 will be reused by VM for other guest systems. The interface 856 allows an external monitor to balance memory of many systems. 857 Everybody who wants to run Linux under VM should select this 858 option. 859 860config CMM_IUCV 861 def_bool y 862 prompt "IUCV special message interface to cooperative memory management" 863 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 864 help 865 Select this option to enable the special message interface to 866 the cooperative memory management. 867 868config APPLDATA_BASE 869 def_bool n 870 prompt "Linux - VM Monitor Stream, base infrastructure" 871 depends on PROC_SYSCTL 872 help 873 This provides a kernel interface for creating and updating z/VM APPLDATA 874 monitor records. The monitor records are updated at certain time 875 intervals, once the timer is started. 876 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 877 i.e. enables or disables monitoring on the Linux side. 878 A custom interval value (in seconds) can be written to 879 /proc/appldata/interval. 880 881 Defaults are 60 seconds interval and timer off. 882 The /proc entries can also be read from, showing the current settings. 883 884config APPLDATA_MEM 885 def_tristate m 886 prompt "Monitor memory management statistics" 887 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 888 help 889 This provides memory management related data to the Linux - VM Monitor 890 Stream, like paging/swapping rate, memory utilisation, etc. 891 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 892 APPLDATA monitor record, i.e. enables or disables monitoring this record 893 on the z/VM side. 894 895 Default is disabled. 896 The /proc entry can also be read from, showing the current settings. 897 898 This can also be compiled as a module, which will be called 899 appldata_mem.o. 900 901config APPLDATA_OS 902 def_tristate m 903 prompt "Monitor OS statistics" 904 depends on APPLDATA_BASE 905 help 906 This provides OS related data to the Linux - VM Monitor Stream, like 907 CPU utilisation, etc. 908 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 909 APPLDATA monitor record, i.e. enables or disables monitoring this record 910 on the z/VM side. 911 912 Default is disabled. 913 This can also be compiled as a module, which will be called 914 appldata_os.o. 915 916config APPLDATA_NET_SUM 917 def_tristate m 918 prompt "Monitor overall network statistics" 919 depends on APPLDATA_BASE && NET 920 help 921 This provides network related data to the Linux - VM Monitor Stream, 922 currently there is only a total sum of network I/O statistics, no 923 per-interface data. 924 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 925 APPLDATA monitor record, i.e. enables or disables monitoring this record 926 on the z/VM side. 927 928 Default is disabled. 929 This can also be compiled as a module, which will be called 930 appldata_net_sum.o. 931 932config S390_HYPFS 933 def_bool y 934 prompt "s390 hypervisor information" 935 help 936 This provides several binary files at (debugfs)/s390_hypfs/ to 937 provide accounting information in an s390 hypervisor environment. 938 939config S390_HYPFS_FS 940 def_bool n 941 prompt "s390 hypervisor file system support" 942 select SYS_HYPERVISOR 943 depends on S390_HYPFS 944 help 945 This is a virtual file system intended to provide accounting 946 information in an s390 hypervisor environment. This file system 947 is deprecated and should not be used. 948 949 Say N if you are unsure. 950 951source "arch/s390/kvm/Kconfig" 952 953config S390_GUEST 954 def_bool y 955 prompt "s390 support for virtio devices" 956 select TTY 957 select VIRTUALIZATION 958 select VIRTIO 959 help 960 Enabling this option adds support for virtio based paravirtual device 961 drivers on s390. 962 963 Select this option if you want to run the kernel as a guest under 964 the KVM hypervisor. 965 966endmenu 967 968config S390_MODULES_SANITY_TEST_HELPERS 969 def_bool n 970 971menu "Selftests" 972 973config S390_UNWIND_SELFTEST 974 def_tristate n 975 depends on KUNIT 976 default KUNIT_ALL_TESTS 977 prompt "Test unwind functions" 978 help 979 This option enables s390 specific stack unwinder testing kernel 980 module. This option is not useful for distributions or general 981 kernels, but only for kernel developers working on architecture code. 982 983 Say N if you are unsure. 984 985config S390_KPROBES_SANITY_TEST 986 def_tristate n 987 prompt "Enable s390 specific kprobes tests" 988 depends on KPROBES 989 depends on KUNIT 990 help 991 This option enables an s390 specific kprobes test module. This option 992 is not useful for distributions or general kernels, but only for kernel 993 developers working on architecture code. 994 995 Say N if you are unsure. 996 997config S390_MODULES_SANITY_TEST 998 def_tristate n 999 depends on KUNIT 1000 default KUNIT_ALL_TESTS 1001 prompt "Enable s390 specific modules tests" 1002 select S390_MODULES_SANITY_TEST_HELPERS 1003 help 1004 This option enables an s390 specific modules test. This option is 1005 not useful for distributions or general kernels, but only for 1006 kernel developers working on architecture code. 1007 1008 Say N if you are unsure. 1009endmenu 1010