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 S390 56 def_bool y 57 # 58 # Note: keep this list sorted alphabetically 59 # 60 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 61 select ALTERNATE_USER_ADDRESS_SPACE 62 select ARCH_32BIT_USTAT_F_TINODE 63 select ARCH_BINFMT_ELF_STATE 64 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 65 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 66 select ARCH_ENABLE_MEMORY_HOTREMOVE 67 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 68 select ARCH_HAS_CURRENT_STACK_POINTER 69 select ARCH_HAS_DEBUG_VIRTUAL 70 select ARCH_HAS_DEBUG_VM_PGTABLE 71 select ARCH_HAS_DEBUG_WX 72 select ARCH_HAS_DEVMEM_IS_ALLOWED 73 select ARCH_HAS_DMA_OPS if PCI 74 select ARCH_HAS_ELF_RANDOMIZE 75 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 76 select ARCH_HAS_FORTIFY_SOURCE 77 select ARCH_HAS_GCOV_PROFILE_ALL 78 select ARCH_HAS_GIGANTIC_PAGE 79 select ARCH_HAS_KCOV 80 select ARCH_HAS_MEMBARRIER_SYNC_CORE 81 select ARCH_HAS_MEM_ENCRYPT 82 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 83 select ARCH_HAS_PTE_SPECIAL 84 select ARCH_HAS_SCALED_CPUTIME 85 select ARCH_HAS_SET_DIRECT_MAP 86 select ARCH_HAS_SET_MEMORY 87 select ARCH_HAS_STRICT_KERNEL_RWX 88 select ARCH_HAS_STRICT_MODULE_RWX 89 select ARCH_HAS_SYSCALL_WRAPPER 90 select ARCH_HAS_UBSAN 91 select ARCH_HAS_VDSO_DATA 92 select ARCH_HAVE_NMI_SAFE_CMPXCHG 93 select ARCH_INLINE_READ_LOCK 94 select ARCH_INLINE_READ_LOCK_BH 95 select ARCH_INLINE_READ_LOCK_IRQ 96 select ARCH_INLINE_READ_LOCK_IRQSAVE 97 select ARCH_INLINE_READ_TRYLOCK 98 select ARCH_INLINE_READ_UNLOCK 99 select ARCH_INLINE_READ_UNLOCK_BH 100 select ARCH_INLINE_READ_UNLOCK_IRQ 101 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 102 select ARCH_INLINE_SPIN_LOCK 103 select ARCH_INLINE_SPIN_LOCK_BH 104 select ARCH_INLINE_SPIN_LOCK_IRQ 105 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 106 select ARCH_INLINE_SPIN_TRYLOCK 107 select ARCH_INLINE_SPIN_TRYLOCK_BH 108 select ARCH_INLINE_SPIN_UNLOCK 109 select ARCH_INLINE_SPIN_UNLOCK_BH 110 select ARCH_INLINE_SPIN_UNLOCK_IRQ 111 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 112 select ARCH_INLINE_WRITE_LOCK 113 select ARCH_INLINE_WRITE_LOCK_BH 114 select ARCH_INLINE_WRITE_LOCK_IRQ 115 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 116 select ARCH_INLINE_WRITE_TRYLOCK 117 select ARCH_INLINE_WRITE_UNLOCK 118 select ARCH_INLINE_WRITE_UNLOCK_BH 119 select ARCH_INLINE_WRITE_UNLOCK_IRQ 120 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 121 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE 122 select ARCH_STACKWALK 123 select ARCH_SUPPORTS_ATOMIC_RMW 124 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 125 select ARCH_SUPPORTS_HUGETLBFS 126 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG 127 select ARCH_SUPPORTS_NUMA_BALANCING 128 select ARCH_SUPPORTS_PER_VMA_LOCK 129 select ARCH_USE_BUILTIN_BSWAP 130 select ARCH_USE_CMPXCHG_LOCKREF 131 select ARCH_USE_SYM_ANNOTATIONS 132 select ARCH_WANTS_NO_INSTR 133 select ARCH_WANT_DEFAULT_BPF_JIT 134 select ARCH_WANT_IPC_PARSE_VERSION 135 select ARCH_WANT_KERNEL_PMD_MKWRITE 136 select ARCH_WANT_LD_ORPHAN_WARN 137 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 138 select BUILDTIME_TABLE_SORT 139 select CLONE_BACKWARDS2 140 select DCACHE_WORD_ACCESS if !KMSAN 141 select DYNAMIC_FTRACE if FUNCTION_TRACER 142 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 143 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 144 select GENERIC_ALLOCATOR 145 select GENERIC_CPU_DEVICES 146 select GENERIC_CPU_AUTOPROBE 147 select GENERIC_CPU_VULNERABILITIES 148 select GENERIC_ENTRY 149 select GENERIC_GETTIMEOFDAY 150 select GENERIC_PTDUMP 151 select GENERIC_SMP_IDLE_THREAD 152 select GENERIC_TIME_VSYSCALL 153 select GENERIC_VDSO_TIME_NS 154 select GENERIC_IOREMAP if PCI 155 select HAVE_ALIGNED_STRUCT_PAGE 156 select HAVE_ARCH_AUDITSYSCALL 157 select HAVE_ARCH_JUMP_LABEL 158 select HAVE_ARCH_JUMP_LABEL_RELATIVE 159 select HAVE_ARCH_KASAN 160 select HAVE_ARCH_KASAN_VMALLOC 161 select HAVE_ARCH_KCSAN 162 select HAVE_ARCH_KMSAN 163 select HAVE_ARCH_KFENCE 164 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 165 select HAVE_ARCH_SECCOMP_FILTER 166 select HAVE_ARCH_SOFT_DIRTY 167 select HAVE_ARCH_STACKLEAK 168 select HAVE_ARCH_TRACEHOOK 169 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 170 select HAVE_ARCH_VMAP_STACK 171 select HAVE_ASM_MODVERSIONS 172 select HAVE_CMPXCHG_DOUBLE 173 select HAVE_CMPXCHG_LOCAL 174 select HAVE_DEBUG_KMEMLEAK 175 select HAVE_DMA_CONTIGUOUS 176 select HAVE_DYNAMIC_FTRACE 177 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 178 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 179 select HAVE_DYNAMIC_FTRACE_WITH_REGS 180 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 181 select HAVE_EFFICIENT_UNALIGNED_ACCESS 182 select HAVE_GUP_FAST 183 select HAVE_FENTRY 184 select HAVE_FTRACE_MCOUNT_RECORD 185 select HAVE_FUNCTION_ARG_ACCESS_API 186 select HAVE_FUNCTION_ERROR_INJECTION 187 select HAVE_FUNCTION_GRAPH_RETVAL 188 select HAVE_FUNCTION_GRAPH_TRACER 189 select HAVE_FUNCTION_TRACER 190 select HAVE_GCC_PLUGINS 191 select HAVE_GENERIC_VDSO 192 select HAVE_IOREMAP_PROT if PCI 193 select HAVE_KERNEL_BZIP2 194 select HAVE_KERNEL_GZIP 195 select HAVE_KERNEL_LZ4 196 select HAVE_KERNEL_LZMA 197 select HAVE_KERNEL_LZO 198 select HAVE_KERNEL_UNCOMPRESSED 199 select HAVE_KERNEL_XZ 200 select HAVE_KERNEL_ZSTD 201 select HAVE_KPROBES 202 select HAVE_KPROBES_ON_FTRACE 203 select HAVE_KRETPROBES 204 select HAVE_LIVEPATCH 205 select HAVE_MEMBLOCK_PHYS_MAP 206 select HAVE_MOD_ARCH_SPECIFIC 207 select HAVE_NMI 208 select HAVE_NOP_MCOUNT 209 select HAVE_PAGE_SIZE_4KB 210 select HAVE_PCI 211 select HAVE_PERF_EVENTS 212 select HAVE_PERF_REGS 213 select HAVE_PERF_USER_STACK_DUMP 214 select HAVE_REGS_AND_STACK_ACCESS_API 215 select HAVE_RELIABLE_STACKTRACE 216 select HAVE_RETHOOK 217 select HAVE_RSEQ 218 select HAVE_SAMPLE_FTRACE_DIRECT 219 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 220 select HAVE_SETUP_PER_CPU_AREA 221 select HAVE_SOFTIRQ_ON_OWN_STACK 222 select HAVE_SYSCALL_TRACEPOINTS 223 select HAVE_VIRT_CPU_ACCOUNTING 224 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 225 select IOMMU_HELPER if PCI 226 select IOMMU_SUPPORT if PCI 227 select MMU_GATHER_MERGE_VMAS 228 select MMU_GATHER_NO_GATHER 229 select MMU_GATHER_RCU_TABLE_FREE 230 select MODULES_USE_ELF_RELA 231 select NEED_DMA_MAP_STATE if PCI 232 select NEED_PER_CPU_EMBED_FIRST_CHUNK 233 select NEED_SG_DMA_LENGTH if PCI 234 select OLD_SIGACTION 235 select OLD_SIGSUSPEND3 236 select PCI_DOMAINS if PCI 237 select PCI_MSI if PCI 238 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 239 select SPARSE_IRQ 240 select SWIOTLB 241 select SYSCTL_EXCEPTION_TRACE 242 select THREAD_INFO_IN_TASK 243 select TRACE_IRQFLAGS_SUPPORT 244 select TTY 245 select USER_STACKTRACE_SUPPORT 246 select VDSO_GETRANDOM 247 select VIRT_CPU_ACCOUNTING 248 select ZONE_DMA 249 # Note: keep the above list sorted alphabetically 250 251config SCHED_OMIT_FRAME_POINTER 252 def_bool y 253 254config PGTABLE_LEVELS 255 int 256 default 5 257 258source "kernel/livepatch/Kconfig" 259 260config ARCH_SUPPORTS_KEXEC 261 def_bool y 262 263config ARCH_SUPPORTS_KEXEC_FILE 264 def_bool y 265 266config ARCH_SUPPORTS_KEXEC_SIG 267 def_bool MODULE_SIG_FORMAT 268 269config ARCH_SUPPORTS_KEXEC_PURGATORY 270 def_bool y 271 272config ARCH_SUPPORTS_CRASH_DUMP 273 def_bool y 274 help 275 Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this. 276 This option also enables s390 zfcpdump. 277 See also <file:Documentation/arch/s390/zfcpdump.rst> 278 279config ARCH_DEFAULT_CRASH_DUMP 280 def_bool y 281 282menu "Processor type and features" 283 284config HAVE_MARCH_Z10_FEATURES 285 def_bool n 286 287config HAVE_MARCH_Z196_FEATURES 288 def_bool n 289 select HAVE_MARCH_Z10_FEATURES 290 291config HAVE_MARCH_ZEC12_FEATURES 292 def_bool n 293 select HAVE_MARCH_Z196_FEATURES 294 295config HAVE_MARCH_Z13_FEATURES 296 def_bool n 297 select HAVE_MARCH_ZEC12_FEATURES 298 299config HAVE_MARCH_Z14_FEATURES 300 def_bool n 301 select HAVE_MARCH_Z13_FEATURES 302 303config HAVE_MARCH_Z15_FEATURES 304 def_bool n 305 select HAVE_MARCH_Z14_FEATURES 306 307config HAVE_MARCH_Z16_FEATURES 308 def_bool n 309 select HAVE_MARCH_Z15_FEATURES 310 311choice 312 prompt "Processor type" 313 default MARCH_Z196 314 315config MARCH_Z10 316 bool "IBM System z10" 317 select HAVE_MARCH_Z10_FEATURES 318 depends on $(cc-option,-march=z10) 319 help 320 Select this to enable optimizations for IBM System z10 (2097 and 2098 321 series). This is the oldest machine generation currently supported. 322 323config MARCH_Z196 324 bool "IBM zEnterprise 114 and 196" 325 select HAVE_MARCH_Z196_FEATURES 326 depends on $(cc-option,-march=z196) 327 help 328 Select this to enable optimizations for IBM zEnterprise 114 and 196 329 (2818 and 2817 series). The kernel will be slightly faster but will 330 not work on older machines. 331 332config MARCH_ZEC12 333 bool "IBM zBC12 and zEC12" 334 select HAVE_MARCH_ZEC12_FEATURES 335 depends on $(cc-option,-march=zEC12) 336 help 337 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 338 2827 series). The kernel will be slightly faster but will not work on 339 older machines. 340 341config MARCH_Z13 342 bool "IBM z13s and z13" 343 select HAVE_MARCH_Z13_FEATURES 344 depends on $(cc-option,-march=z13) 345 help 346 Select this to enable optimizations for IBM z13s and z13 (2965 and 347 2964 series). The kernel will be slightly faster but will not work on 348 older machines. 349 350config MARCH_Z14 351 bool "IBM z14 ZR1 and z14" 352 select HAVE_MARCH_Z14_FEATURES 353 depends on $(cc-option,-march=z14) 354 help 355 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 356 and 3906 series). The kernel will be slightly faster but will not 357 work on older machines. 358 359config MARCH_Z15 360 bool "IBM z15" 361 select HAVE_MARCH_Z15_FEATURES 362 depends on $(cc-option,-march=z15) 363 help 364 Select this to enable optimizations for IBM z15 (8562 365 and 8561 series). The kernel will be slightly faster but will not 366 work on older machines. 367 368config MARCH_Z16 369 bool "IBM z16" 370 select HAVE_MARCH_Z16_FEATURES 371 depends on $(cc-option,-march=z16) 372 help 373 Select this to enable optimizations for IBM z16 (3931 and 374 3932 series). 375 376endchoice 377 378config MARCH_Z10_TUNE 379 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 380 381config MARCH_Z196_TUNE 382 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 383 384config MARCH_ZEC12_TUNE 385 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 386 387config MARCH_Z13_TUNE 388 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 389 390config MARCH_Z14_TUNE 391 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 392 393config MARCH_Z15_TUNE 394 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 395 396config MARCH_Z16_TUNE 397 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 398 399choice 400 prompt "Tune code generation" 401 default TUNE_DEFAULT 402 help 403 Cause the compiler to tune (-mtune) the generated code for a machine. 404 This will make the code run faster on the selected machine but 405 somewhat slower on other machines. 406 This option only changes how the compiler emits instructions, not the 407 selection of instructions itself, so the resulting kernel will run on 408 all other machines. 409 410config TUNE_DEFAULT 411 bool "Default" 412 help 413 Tune the generated code for the target processor for which the kernel 414 will be compiled. 415 416config TUNE_Z10 417 bool "IBM System z10" 418 419config TUNE_Z196 420 bool "IBM zEnterprise 114 and 196" 421 depends on $(cc-option,-mtune=z196) 422 423config TUNE_ZEC12 424 bool "IBM zBC12 and zEC12" 425 depends on $(cc-option,-mtune=zEC12) 426 427config TUNE_Z13 428 bool "IBM z13s and z13" 429 depends on $(cc-option,-mtune=z13) 430 431config TUNE_Z14 432 bool "IBM z14 ZR1 and z14" 433 depends on $(cc-option,-mtune=z14) 434 435config TUNE_Z15 436 bool "IBM z15" 437 depends on $(cc-option,-mtune=z15) 438 439config TUNE_Z16 440 bool "IBM z16" 441 depends on $(cc-option,-mtune=z16) 442 443endchoice 444 445config 64BIT 446 def_bool y 447 448config COMMAND_LINE_SIZE 449 int "Maximum size of kernel command line" 450 default 4096 451 range 896 1048576 452 help 453 This allows you to specify the maximum length of the kernel command 454 line. 455 456config COMPAT 457 def_bool n 458 prompt "Kernel support for 31 bit emulation" 459 select ARCH_WANT_OLD_COMPAT_IPC 460 select COMPAT_OLD_SIGACTION 461 select HAVE_UID16 462 depends on MULTIUSER 463 depends on !CC_IS_CLANG && !LD_IS_LLD 464 help 465 Select this option if you want to enable your system kernel to 466 handle system-calls from ELF binaries for 31 bit ESA. This option 467 (and some other stuff like libraries and such) is needed for 468 executing 31 bit applications. 469 470 If unsure say N. 471 472config SMP 473 def_bool y 474 475config NR_CPUS 476 int "Maximum number of CPUs (2-512)" 477 range 2 512 478 default "64" 479 help 480 This allows you to specify the maximum number of CPUs which this 481 kernel will support. The maximum supported value is 512 and the 482 minimum value which makes sense is 2. 483 484 This is purely to save memory - each supported CPU adds 485 approximately sixteen kilobytes to the kernel image. 486 487config HOTPLUG_CPU 488 def_bool y 489 490config NUMA 491 bool "NUMA support" 492 depends on SCHED_TOPOLOGY 493 default n 494 help 495 Enable NUMA support 496 497 This option adds NUMA support to the kernel. 498 499config NODES_SHIFT 500 int 501 depends on NUMA 502 default "1" 503 504config SCHED_SMT 505 def_bool n 506 507config SCHED_MC 508 def_bool n 509 510config SCHED_TOPOLOGY 511 def_bool y 512 prompt "Topology scheduler support" 513 select SCHED_SMT 514 select SCHED_MC 515 help 516 Topology scheduler support improves the CPU scheduler's decision 517 making when dealing with machines that have multi-threading, 518 multiple cores or multiple books. 519 520config SCHED_TOPOLOGY_VERTICAL 521 def_bool y 522 bool "Use vertical CPU polarization by default" 523 depends on SCHED_TOPOLOGY 524 help 525 Use vertical CPU polarization by default if available. 526 The default CPU polarization is horizontal. 527 528config HIPERDISPATCH_ON 529 def_bool y 530 bool "Use hiperdispatch on vertical polarization by default" 531 depends on SCHED_TOPOLOGY 532 depends on PROC_SYSCTL 533 help 534 Hiperdispatch aims to improve the CPU scheduler's decision 535 making when using vertical polarization by adjusting CPU 536 capacities dynamically. Set this option to use hiperdispatch 537 on vertical polarization by default. This can be overwritten 538 by sysctl's s390.hiperdispatch attribute later on. 539 540source "kernel/Kconfig.hz" 541 542config CERT_STORE 543 bool "Get user certificates via DIAG320" 544 depends on KEYS 545 select CRYPTO_LIB_SHA256 546 help 547 Enable this option if you want to access user-provided secure boot 548 certificates via DIAG 0x320. 549 550 These certificates will be made available via the keyring named 551 'cert_store'. 552 553config KERNEL_NOBP 554 def_bool n 555 prompt "Enable modified branch prediction for the kernel by default" 556 help 557 If this option is selected the kernel will switch to a modified 558 branch prediction mode if the firmware interface is available. 559 The modified branch prediction mode improves the behaviour in 560 regard to speculative execution. 561 562 With the option enabled the kernel parameter "nobp=0" or "nospec" 563 can be used to run the kernel in the normal branch prediction mode. 564 565 With the option disabled the modified branch prediction mode is 566 enabled with the "nobp=1" kernel parameter. 567 568 If unsure, say N. 569 570config EXPOLINE 571 def_bool n 572 depends on $(cc-option,-mindirect-branch=thunk) 573 prompt "Avoid speculative indirect branches in the kernel" 574 help 575 Compile the kernel with the expoline compiler options to guard 576 against kernel-to-user data leaks by avoiding speculative indirect 577 branches. 578 Requires a compiler with -mindirect-branch=thunk support for full 579 protection. The kernel may run slower. 580 581 If unsure, say N. 582 583config EXPOLINE_EXTERN 584 def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \ 585 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 586 help 587 Generate expolines as external functions if the compiler supports it. 588 This option is required for some tooling like kpatch, if expolines 589 are enabled. The kernel is compiled with 590 -mindirect-branch=thunk-extern, which requires a newer compiler. 591 592choice 593 prompt "Expoline default" 594 depends on EXPOLINE 595 default EXPOLINE_FULL 596 597config EXPOLINE_OFF 598 bool "spectre_v2=off" 599 600config EXPOLINE_AUTO 601 bool "spectre_v2=auto" 602 603config EXPOLINE_FULL 604 bool "spectre_v2=on" 605 606endchoice 607 608config RELOCATABLE 609 def_bool y 610 help 611 This builds a kernel image that retains relocation information 612 so it can be loaded at an arbitrary address. 613 The relocations make the kernel image about 15% larger (compressed 614 10%), but are discarded at runtime. 615 Note: this option exists only for documentation purposes, please do 616 not remove it. 617 618config RANDOMIZE_BASE 619 bool "Randomize the address of the kernel image (KASLR)" 620 default y 621 help 622 In support of Kernel Address Space Layout Randomization (KASLR), 623 this randomizes the address at which the kernel image is loaded, 624 as a security feature that deters exploit attempts relying on 625 knowledge of the location of kernel internals. 626 627config RANDOMIZE_IDENTITY_BASE 628 bool "Randomize the address of the identity mapping base" 629 depends on RANDOMIZE_BASE 630 default DEBUG_VM 631 help 632 The identity mapping base address is pinned to zero by default. 633 Allow randomization of that base to expose otherwise missed 634 notion of physical and virtual addresses of data structures. 635 That does not have any impact on the base address at which the 636 kernel image is loaded. 637 638 If unsure, say N 639 640config KERNEL_IMAGE_BASE 641 hex "Kernel image base address" 642 range 0x100000 0x1FFFFFE0000000 if !KASAN 643 range 0x100000 0x1BFFFFE0000000 if KASAN 644 default 0x3FFE0000000 if !KASAN 645 default 0x7FFFE0000000 if KASAN 646 help 647 This is the address at which the kernel image is loaded in case 648 Kernel Address Space Layout Randomization (KASLR) is disabled. 649 650 In case the Protected virtualization guest support is enabled the 651 Ultravisor imposes a virtual address limit. If the value of this 652 option leads to the kernel image exceeding the Ultravisor limit, 653 this option is ignored and the image is loaded below the limit. 654 655 If the value of this option leads to the kernel image overlapping 656 the virtual memory where other data structures are located, this 657 option is ignored and the image is loaded above the structures. 658 659endmenu 660 661menu "Memory setup" 662 663config ARCH_SPARSEMEM_ENABLE 664 def_bool y 665 select SPARSEMEM_VMEMMAP_ENABLE 666 select SPARSEMEM_VMEMMAP 667 668config ARCH_SPARSEMEM_DEFAULT 669 def_bool y 670 671config MAX_PHYSMEM_BITS 672 int "Maximum size of supported physical memory in bits (42-53)" 673 range 42 53 674 default "46" 675 help 676 This option specifies the maximum supported size of physical memory 677 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 678 Increasing the number of bits also increases the kernel image size. 679 By default 46 bits (64TB) are supported. 680 681config CHECK_STACK 682 def_bool y 683 depends on !VMAP_STACK 684 prompt "Detect kernel stack overflow" 685 help 686 This option enables the compiler option -mstack-guard and 687 -mstack-size if they are available. If the compiler supports them 688 it will emit additional code to each function prolog to trigger 689 an illegal operation if the kernel stack is about to overflow. 690 691 Say N if you are unsure. 692 693config STACK_GUARD 694 int "Size of the guard area (128-1024)" 695 range 128 1024 696 depends on CHECK_STACK 697 default "256" 698 help 699 This allows you to specify the size of the guard area at the lower 700 end of the kernel stack. If the kernel stack points into the guard 701 area on function entry an illegal operation is triggered. The size 702 needs to be a power of 2. Please keep in mind that the size of an 703 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 704 The minimum size for the stack guard should be 256 for 31 bit and 705 512 for 64 bit. 706 707endmenu 708 709menu "I/O subsystem" 710 711config QDIO 712 def_tristate y 713 prompt "QDIO support" 714 help 715 This driver provides the Queued Direct I/O base support for 716 IBM System z. 717 718 To compile this driver as a module, choose M here: the 719 module will be called qdio. 720 721 If unsure, say Y. 722 723if PCI 724 725config PCI_NR_FUNCTIONS 726 int "Maximum number of PCI functions (1-4096)" 727 range 1 4096 728 default "512" 729 help 730 This allows you to specify the maximum number of PCI functions which 731 this kernel will support. 732 733endif # PCI 734 735config HAS_IOMEM 736 def_bool PCI 737 738config CHSC_SCH 739 def_tristate m 740 prompt "Support for CHSC subchannels" 741 help 742 This driver allows usage of CHSC subchannels. A CHSC subchannel 743 is usually present on LPAR only. 744 The driver creates a device /dev/chsc, which may be used to 745 obtain I/O configuration information about the machine and 746 to issue asynchronous chsc commands (DANGEROUS). 747 You will usually only want to use this interface on a special 748 LPAR designated for system management. 749 750 To compile this driver as a module, choose M here: the 751 module will be called chsc_sch. 752 753 If unsure, say N. 754 755config SCM_BUS 756 def_bool y 757 prompt "SCM bus driver" 758 help 759 Bus driver for Storage Class Memory. 760 761config EADM_SCH 762 def_tristate m 763 prompt "Support for EADM subchannels" 764 depends on SCM_BUS 765 help 766 This driver allows usage of EADM subchannels. EADM subchannels act 767 as a communication vehicle for SCM increments. 768 769 To compile this driver as a module, choose M here: the 770 module will be called eadm_sch. 771 772config AP 773 def_tristate y 774 prompt "Support for Adjunct Processors (ap)" 775 help 776 This driver allows usage to Adjunct Processor (AP) devices via 777 the ap bus, cards and queues. Supported Adjunct Processors are 778 the CryptoExpress Cards (CEX). 779 780 To compile this driver as a module, choose M here: the 781 module will be called ap. 782 783 If unsure, say Y (default). 784 785config AP_DEBUG 786 def_bool n 787 prompt "Enable debug features for Adjunct Processor (ap) devices" 788 depends on AP 789 help 790 Say 'Y' here to enable some additional debug features for Adjunct 791 Processor (ap) devices. 792 793 There will be some more sysfs attributes displayed for ap queues. 794 795 Do not enable on production level kernel build. 796 797 If unsure, say N. 798 799config VFIO_CCW 800 def_tristate n 801 prompt "Support for VFIO-CCW subchannels" 802 depends on VFIO 803 select VFIO_MDEV 804 help 805 This driver allows usage of I/O subchannels via VFIO-CCW. 806 807 To compile this driver as a module, choose M here: the 808 module will be called vfio_ccw. 809 810config VFIO_AP 811 def_tristate n 812 prompt "VFIO support for AP devices" 813 depends on KVM 814 depends on VFIO 815 depends on AP 816 select VFIO_MDEV 817 help 818 This driver grants access to Adjunct Processor (AP) devices 819 via the VFIO mediated device interface. 820 821 To compile this driver as a module, choose M here: the module 822 will be called vfio_ap. 823 824endmenu 825 826config CCW 827 def_bool y 828 829config HAVE_PNETID 830 tristate 831 default (SMC || CCWGROUP) 832 833menu "Virtualization" 834 835config PFAULT 836 def_bool y 837 prompt "Pseudo page fault support" 838 help 839 Select this option, if you want to use PFAULT pseudo page fault 840 handling under VM. If running native or in LPAR, this option 841 has no effect. If your VM does not support PFAULT, PAGEEX 842 pseudo page fault handling will be used. 843 Note that VM 4.2 supports PFAULT but has a bug in its 844 implementation that causes some problems. 845 Everybody who wants to run Linux under VM != VM4.2 should select 846 this option. 847 848config CMM 849 def_tristate n 850 prompt "Cooperative memory management" 851 help 852 Select this option, if you want to enable the kernel interface 853 to reduce the memory size of the system. This is accomplished 854 by allocating pages of memory and put them "on hold". This only 855 makes sense for a system running under VM where the unused pages 856 will be reused by VM for other guest systems. The interface 857 allows an external monitor to balance memory of many systems. 858 Everybody who wants to run Linux under VM should select this 859 option. 860 861config CMM_IUCV 862 def_bool y 863 prompt "IUCV special message interface to cooperative memory management" 864 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 865 help 866 Select this option to enable the special message interface to 867 the cooperative memory management. 868 869config APPLDATA_BASE 870 def_bool n 871 prompt "Linux - VM Monitor Stream, base infrastructure" 872 depends on PROC_SYSCTL 873 help 874 This provides a kernel interface for creating and updating z/VM APPLDATA 875 monitor records. The monitor records are updated at certain time 876 intervals, once the timer is started. 877 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 878 i.e. enables or disables monitoring on the Linux side. 879 A custom interval value (in seconds) can be written to 880 /proc/appldata/interval. 881 882 Defaults are 60 seconds interval and timer off. 883 The /proc entries can also be read from, showing the current settings. 884 885config APPLDATA_MEM 886 def_tristate m 887 prompt "Monitor memory management statistics" 888 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 889 help 890 This provides memory management related data to the Linux - VM Monitor 891 Stream, like paging/swapping rate, memory utilisation, etc. 892 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 893 APPLDATA monitor record, i.e. enables or disables monitoring this record 894 on the z/VM side. 895 896 Default is disabled. 897 The /proc entry can also be read from, showing the current settings. 898 899 This can also be compiled as a module, which will be called 900 appldata_mem.o. 901 902config APPLDATA_OS 903 def_tristate m 904 prompt "Monitor OS statistics" 905 depends on APPLDATA_BASE 906 help 907 This provides OS related data to the Linux - VM Monitor Stream, like 908 CPU utilisation, etc. 909 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 910 APPLDATA monitor record, i.e. enables or disables monitoring this record 911 on the z/VM side. 912 913 Default is disabled. 914 This can also be compiled as a module, which will be called 915 appldata_os.o. 916 917config APPLDATA_NET_SUM 918 def_tristate m 919 prompt "Monitor overall network statistics" 920 depends on APPLDATA_BASE && NET 921 help 922 This provides network related data to the Linux - VM Monitor Stream, 923 currently there is only a total sum of network I/O statistics, no 924 per-interface data. 925 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 926 APPLDATA monitor record, i.e. enables or disables monitoring this record 927 on the z/VM side. 928 929 Default is disabled. 930 This can also be compiled as a module, which will be called 931 appldata_net_sum.o. 932 933config S390_HYPFS 934 def_bool y 935 prompt "s390 hypervisor information" 936 help 937 This provides several binary files at (debugfs)/s390_hypfs/ to 938 provide accounting information in an s390 hypervisor environment. 939 940config S390_HYPFS_FS 941 def_bool n 942 prompt "s390 hypervisor file system support" 943 select SYS_HYPERVISOR 944 depends on S390_HYPFS 945 help 946 This is a virtual file system intended to provide accounting 947 information in an s390 hypervisor environment. This file system 948 is deprecated and should not be used. 949 950 Say N if you are unsure. 951 952source "arch/s390/kvm/Kconfig" 953 954config S390_GUEST 955 def_bool y 956 prompt "s390 support for virtio devices" 957 select TTY 958 select VIRTUALIZATION 959 select VIRTIO 960 help 961 Enabling this option adds support for virtio based paravirtual device 962 drivers on s390. 963 964 Select this option if you want to run the kernel as a guest under 965 the KVM hypervisor. 966 967endmenu 968 969config S390_MODULES_SANITY_TEST_HELPERS 970 def_bool n 971 972menu "Selftests" 973 974config S390_UNWIND_SELFTEST 975 def_tristate n 976 depends on KUNIT 977 default KUNIT_ALL_TESTS 978 prompt "Test unwind functions" 979 help 980 This option enables s390 specific stack unwinder testing kernel 981 module. This option is not useful for distributions or general 982 kernels, but only for kernel developers working on architecture code. 983 984 Say N if you are unsure. 985 986config S390_KPROBES_SANITY_TEST 987 def_tristate n 988 prompt "Enable s390 specific kprobes tests" 989 depends on KPROBES 990 depends on KUNIT 991 help 992 This option enables an s390 specific kprobes test module. This option 993 is not useful for distributions or general kernels, but only for kernel 994 developers working on architecture code. 995 996 Say N if you are unsure. 997 998config S390_MODULES_SANITY_TEST 999 def_tristate n 1000 depends on KUNIT 1001 default KUNIT_ALL_TESTS 1002 prompt "Enable s390 specific modules tests" 1003 select S390_MODULES_SANITY_TEST_HELPERS 1004 help 1005 This option enables an s390 specific modules test. This option is 1006 not useful for distributions or general kernels, but only for 1007 kernel developers working on architecture code. 1008 1009 Say N if you are unsure. 1010endmenu 1011