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 279menu "Processor type and features" 280 281config HAVE_MARCH_Z10_FEATURES 282 def_bool n 283 284config HAVE_MARCH_Z196_FEATURES 285 def_bool n 286 select HAVE_MARCH_Z10_FEATURES 287 288config HAVE_MARCH_ZEC12_FEATURES 289 def_bool n 290 select HAVE_MARCH_Z196_FEATURES 291 292config HAVE_MARCH_Z13_FEATURES 293 def_bool n 294 select HAVE_MARCH_ZEC12_FEATURES 295 296config HAVE_MARCH_Z14_FEATURES 297 def_bool n 298 select HAVE_MARCH_Z13_FEATURES 299 300config HAVE_MARCH_Z15_FEATURES 301 def_bool n 302 select HAVE_MARCH_Z14_FEATURES 303 304config HAVE_MARCH_Z16_FEATURES 305 def_bool n 306 select HAVE_MARCH_Z15_FEATURES 307 308choice 309 prompt "Processor type" 310 default MARCH_Z196 311 312config MARCH_Z10 313 bool "IBM System z10" 314 select HAVE_MARCH_Z10_FEATURES 315 depends on $(cc-option,-march=z10) 316 help 317 Select this to enable optimizations for IBM System z10 (2097 and 2098 318 series). This is the oldest machine generation currently supported. 319 320config MARCH_Z196 321 bool "IBM zEnterprise 114 and 196" 322 select HAVE_MARCH_Z196_FEATURES 323 depends on $(cc-option,-march=z196) 324 help 325 Select this to enable optimizations for IBM zEnterprise 114 and 196 326 (2818 and 2817 series). The kernel will be slightly faster but will 327 not work on older machines. 328 329config MARCH_ZEC12 330 bool "IBM zBC12 and zEC12" 331 select HAVE_MARCH_ZEC12_FEATURES 332 depends on $(cc-option,-march=zEC12) 333 help 334 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 335 2827 series). The kernel will be slightly faster but will not work on 336 older machines. 337 338config MARCH_Z13 339 bool "IBM z13s and z13" 340 select HAVE_MARCH_Z13_FEATURES 341 depends on $(cc-option,-march=z13) 342 help 343 Select this to enable optimizations for IBM z13s and z13 (2965 and 344 2964 series). The kernel will be slightly faster but will not work on 345 older machines. 346 347config MARCH_Z14 348 bool "IBM z14 ZR1 and z14" 349 select HAVE_MARCH_Z14_FEATURES 350 depends on $(cc-option,-march=z14) 351 help 352 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 353 and 3906 series). The kernel will be slightly faster but will not 354 work on older machines. 355 356config MARCH_Z15 357 bool "IBM z15" 358 select HAVE_MARCH_Z15_FEATURES 359 depends on $(cc-option,-march=z15) 360 help 361 Select this to enable optimizations for IBM z15 (8562 362 and 8561 series). The kernel will be slightly faster but will not 363 work on older machines. 364 365config MARCH_Z16 366 bool "IBM z16" 367 select HAVE_MARCH_Z16_FEATURES 368 depends on $(cc-option,-march=z16) 369 help 370 Select this to enable optimizations for IBM z16 (3931 and 371 3932 series). 372 373endchoice 374 375config MARCH_Z10_TUNE 376 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 377 378config MARCH_Z196_TUNE 379 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 380 381config MARCH_ZEC12_TUNE 382 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 383 384config MARCH_Z13_TUNE 385 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 386 387config MARCH_Z14_TUNE 388 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 389 390config MARCH_Z15_TUNE 391 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 392 393config MARCH_Z16_TUNE 394 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 395 396choice 397 prompt "Tune code generation" 398 default TUNE_DEFAULT 399 help 400 Cause the compiler to tune (-mtune) the generated code for a machine. 401 This will make the code run faster on the selected machine but 402 somewhat slower on other machines. 403 This option only changes how the compiler emits instructions, not the 404 selection of instructions itself, so the resulting kernel will run on 405 all other machines. 406 407config TUNE_DEFAULT 408 bool "Default" 409 help 410 Tune the generated code for the target processor for which the kernel 411 will be compiled. 412 413config TUNE_Z10 414 bool "IBM System z10" 415 416config TUNE_Z196 417 bool "IBM zEnterprise 114 and 196" 418 depends on $(cc-option,-mtune=z196) 419 420config TUNE_ZEC12 421 bool "IBM zBC12 and zEC12" 422 depends on $(cc-option,-mtune=zEC12) 423 424config TUNE_Z13 425 bool "IBM z13s and z13" 426 depends on $(cc-option,-mtune=z13) 427 428config TUNE_Z14 429 bool "IBM z14 ZR1 and z14" 430 depends on $(cc-option,-mtune=z14) 431 432config TUNE_Z15 433 bool "IBM z15" 434 depends on $(cc-option,-mtune=z15) 435 436config TUNE_Z16 437 bool "IBM z16" 438 depends on $(cc-option,-mtune=z16) 439 440endchoice 441 442config 64BIT 443 def_bool y 444 445config COMMAND_LINE_SIZE 446 int "Maximum size of kernel command line" 447 default 4096 448 range 896 1048576 449 help 450 This allows you to specify the maximum length of the kernel command 451 line. 452 453config COMPAT 454 def_bool n 455 prompt "Kernel support for 31 bit emulation" 456 select ARCH_WANT_OLD_COMPAT_IPC 457 select COMPAT_OLD_SIGACTION 458 select HAVE_UID16 459 depends on MULTIUSER 460 depends on !CC_IS_CLANG && !LD_IS_LLD 461 help 462 Select this option if you want to enable your system kernel to 463 handle system-calls from ELF binaries for 31 bit ESA. This option 464 (and some other stuff like libraries and such) is needed for 465 executing 31 bit applications. 466 467 If unsure say N. 468 469config SMP 470 def_bool y 471 472config NR_CPUS 473 int "Maximum number of CPUs (2-512)" 474 range 2 512 475 default "64" 476 help 477 This allows you to specify the maximum number of CPUs which this 478 kernel will support. The maximum supported value is 512 and the 479 minimum value which makes sense is 2. 480 481 This is purely to save memory - each supported CPU adds 482 approximately sixteen kilobytes to the kernel image. 483 484config HOTPLUG_CPU 485 def_bool y 486 487config NUMA 488 bool "NUMA support" 489 depends on SCHED_TOPOLOGY 490 default n 491 help 492 Enable NUMA support 493 494 This option adds NUMA support to the kernel. 495 496config NODES_SHIFT 497 int 498 depends on NUMA 499 default "1" 500 501config SCHED_SMT 502 def_bool n 503 504config SCHED_MC 505 def_bool n 506 507config SCHED_TOPOLOGY 508 def_bool y 509 prompt "Topology scheduler support" 510 select SCHED_SMT 511 select SCHED_MC 512 help 513 Topology scheduler support improves the CPU scheduler's decision 514 making when dealing with machines that have multi-threading, 515 multiple cores or multiple books. 516 517config SCHED_TOPOLOGY_VERTICAL 518 def_bool y 519 bool "Use vertical CPU polarization by default" 520 depends on SCHED_TOPOLOGY 521 help 522 Use vertical CPU polarization by default if available. 523 The default CPU polarization is horizontal. 524 525config HIPERDISPATCH_ON 526 def_bool y 527 bool "Use hiperdispatch on vertical polarization by default" 528 depends on SCHED_TOPOLOGY 529 depends on PROC_SYSCTL 530 help 531 Hiperdispatch aims to improve the CPU scheduler's decision 532 making when using vertical polarization by adjusting CPU 533 capacities dynamically. Set this option to use hiperdispatch 534 on vertical polarization by default. This can be overwritten 535 by sysctl's s390.hiperdispatch attribute later on. 536 537source "kernel/Kconfig.hz" 538 539config CERT_STORE 540 bool "Get user certificates via DIAG320" 541 depends on KEYS 542 select CRYPTO_LIB_SHA256 543 help 544 Enable this option if you want to access user-provided secure boot 545 certificates via DIAG 0x320. 546 547 These certificates will be made available via the keyring named 548 'cert_store'. 549 550config KERNEL_NOBP 551 def_bool n 552 prompt "Enable modified branch prediction for the kernel by default" 553 help 554 If this option is selected the kernel will switch to a modified 555 branch prediction mode if the firmware interface is available. 556 The modified branch prediction mode improves the behaviour in 557 regard to speculative execution. 558 559 With the option enabled the kernel parameter "nobp=0" or "nospec" 560 can be used to run the kernel in the normal branch prediction mode. 561 562 With the option disabled the modified branch prediction mode is 563 enabled with the "nobp=1" kernel parameter. 564 565 If unsure, say N. 566 567config EXPOLINE 568 def_bool n 569 depends on $(cc-option,-mindirect-branch=thunk) 570 prompt "Avoid speculative indirect branches in the kernel" 571 help 572 Compile the kernel with the expoline compiler options to guard 573 against kernel-to-user data leaks by avoiding speculative indirect 574 branches. 575 Requires a compiler with -mindirect-branch=thunk support for full 576 protection. The kernel may run slower. 577 578 If unsure, say N. 579 580config EXPOLINE_EXTERN 581 def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \ 582 $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 583 help 584 Generate expolines as external functions if the compiler supports it. 585 This option is required for some tooling like kpatch, if expolines 586 are enabled. The kernel is compiled with 587 -mindirect-branch=thunk-extern, which requires a newer compiler. 588 589choice 590 prompt "Expoline default" 591 depends on EXPOLINE 592 default EXPOLINE_FULL 593 594config EXPOLINE_OFF 595 bool "spectre_v2=off" 596 597config EXPOLINE_AUTO 598 bool "spectre_v2=auto" 599 600config EXPOLINE_FULL 601 bool "spectre_v2=on" 602 603endchoice 604 605config RELOCATABLE 606 def_bool y 607 help 608 This builds a kernel image that retains relocation information 609 so it can be loaded at an arbitrary address. 610 The relocations make the kernel image about 15% larger (compressed 611 10%), but are discarded at runtime. 612 Note: this option exists only for documentation purposes, please do 613 not remove it. 614 615config RANDOMIZE_BASE 616 bool "Randomize the address of the kernel image (KASLR)" 617 default y 618 help 619 In support of Kernel Address Space Layout Randomization (KASLR), 620 this randomizes the address at which the kernel image is loaded, 621 as a security feature that deters exploit attempts relying on 622 knowledge of the location of kernel internals. 623 624config RANDOMIZE_IDENTITY_BASE 625 bool "Randomize the address of the identity mapping base" 626 depends on RANDOMIZE_BASE 627 default DEBUG_VM 628 help 629 The identity mapping base address is pinned to zero by default. 630 Allow randomization of that base to expose otherwise missed 631 notion of physical and virtual addresses of data structures. 632 That does not have any impact on the base address at which the 633 kernel image is loaded. 634 635 If unsure, say N 636 637config KERNEL_IMAGE_BASE 638 hex "Kernel image base address" 639 range 0x100000 0x1FFFFFE0000000 if !KASAN 640 range 0x100000 0x1BFFFFE0000000 if KASAN 641 default 0x3FFE0000000 if !KASAN 642 default 0x7FFFE0000000 if KASAN 643 help 644 This is the address at which the kernel image is loaded in case 645 Kernel Address Space Layout Randomization (KASLR) is disabled. 646 647 In case the Protected virtualization guest support is enabled the 648 Ultravisor imposes a virtual address limit. If the value of this 649 option leads to the kernel image exceeding the Ultravisor limit, 650 this option is ignored and the image is loaded below the limit. 651 652 If the value of this option leads to the kernel image overlapping 653 the virtual memory where other data structures are located, this 654 option is ignored and the image is loaded above the structures. 655 656endmenu 657 658menu "Memory setup" 659 660config ARCH_SPARSEMEM_ENABLE 661 def_bool y 662 select SPARSEMEM_VMEMMAP_ENABLE 663 select SPARSEMEM_VMEMMAP 664 665config ARCH_SPARSEMEM_DEFAULT 666 def_bool y 667 668config MAX_PHYSMEM_BITS 669 int "Maximum size of supported physical memory in bits (42-53)" 670 range 42 53 671 default "46" 672 help 673 This option specifies the maximum supported size of physical memory 674 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 675 Increasing the number of bits also increases the kernel image size. 676 By default 46 bits (64TB) are supported. 677 678config CHECK_STACK 679 def_bool y 680 depends on !VMAP_STACK 681 prompt "Detect kernel stack overflow" 682 help 683 This option enables the compiler option -mstack-guard and 684 -mstack-size if they are available. If the compiler supports them 685 it will emit additional code to each function prolog to trigger 686 an illegal operation if the kernel stack is about to overflow. 687 688 Say N if you are unsure. 689 690config STACK_GUARD 691 int "Size of the guard area (128-1024)" 692 range 128 1024 693 depends on CHECK_STACK 694 default "256" 695 help 696 This allows you to specify the size of the guard area at the lower 697 end of the kernel stack. If the kernel stack points into the guard 698 area on function entry an illegal operation is triggered. The size 699 needs to be a power of 2. Please keep in mind that the size of an 700 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 701 The minimum size for the stack guard should be 256 for 31 bit and 702 512 for 64 bit. 703 704endmenu 705 706menu "I/O subsystem" 707 708config QDIO 709 def_tristate y 710 prompt "QDIO support" 711 help 712 This driver provides the Queued Direct I/O base support for 713 IBM System z. 714 715 To compile this driver as a module, choose M here: the 716 module will be called qdio. 717 718 If unsure, say Y. 719 720if PCI 721 722config PCI_NR_FUNCTIONS 723 int "Maximum number of PCI functions (1-4096)" 724 range 1 4096 725 default "512" 726 help 727 This allows you to specify the maximum number of PCI functions which 728 this kernel will support. 729 730endif # PCI 731 732config HAS_IOMEM 733 def_bool PCI 734 735config CHSC_SCH 736 def_tristate m 737 prompt "Support for CHSC subchannels" 738 help 739 This driver allows usage of CHSC subchannels. A CHSC subchannel 740 is usually present on LPAR only. 741 The driver creates a device /dev/chsc, which may be used to 742 obtain I/O configuration information about the machine and 743 to issue asynchronous chsc commands (DANGEROUS). 744 You will usually only want to use this interface on a special 745 LPAR designated for system management. 746 747 To compile this driver as a module, choose M here: the 748 module will be called chsc_sch. 749 750 If unsure, say N. 751 752config SCM_BUS 753 def_bool y 754 prompt "SCM bus driver" 755 help 756 Bus driver for Storage Class Memory. 757 758config EADM_SCH 759 def_tristate m 760 prompt "Support for EADM subchannels" 761 depends on SCM_BUS 762 help 763 This driver allows usage of EADM subchannels. EADM subchannels act 764 as a communication vehicle for SCM increments. 765 766 To compile this driver as a module, choose M here: the 767 module will be called eadm_sch. 768 769config AP 770 def_tristate y 771 prompt "Support for Adjunct Processors (ap)" 772 help 773 This driver allows usage to Adjunct Processor (AP) devices via 774 the ap bus, cards and queues. Supported Adjunct Processors are 775 the CryptoExpress Cards (CEX). 776 777 To compile this driver as a module, choose M here: the 778 module will be called ap. 779 780 If unsure, say Y (default). 781 782config AP_DEBUG 783 def_bool n 784 prompt "Enable debug features for Adjunct Processor (ap) devices" 785 depends on AP 786 help 787 Say 'Y' here to enable some additional debug features for Adjunct 788 Processor (ap) devices. 789 790 There will be some more sysfs attributes displayed for ap queues. 791 792 Do not enable on production level kernel build. 793 794 If unsure, say N. 795 796config VFIO_CCW 797 def_tristate n 798 prompt "Support for VFIO-CCW subchannels" 799 depends on VFIO 800 select VFIO_MDEV 801 help 802 This driver allows usage of I/O subchannels via VFIO-CCW. 803 804 To compile this driver as a module, choose M here: the 805 module will be called vfio_ccw. 806 807config VFIO_AP 808 def_tristate n 809 prompt "VFIO support for AP devices" 810 depends on KVM 811 depends on VFIO 812 depends on AP 813 select VFIO_MDEV 814 help 815 This driver grants access to Adjunct Processor (AP) devices 816 via the VFIO mediated device interface. 817 818 To compile this driver as a module, choose M here: the module 819 will be called vfio_ap. 820 821endmenu 822 823config CCW 824 def_bool y 825 826config HAVE_PNETID 827 tristate 828 default (SMC || CCWGROUP) 829 830menu "Virtualization" 831 832config PFAULT 833 def_bool y 834 prompt "Pseudo page fault support" 835 help 836 Select this option, if you want to use PFAULT pseudo page fault 837 handling under VM. If running native or in LPAR, this option 838 has no effect. If your VM does not support PFAULT, PAGEEX 839 pseudo page fault handling will be used. 840 Note that VM 4.2 supports PFAULT but has a bug in its 841 implementation that causes some problems. 842 Everybody who wants to run Linux under VM != VM4.2 should select 843 this option. 844 845config CMM 846 def_tristate n 847 prompt "Cooperative memory management" 848 help 849 Select this option, if you want to enable the kernel interface 850 to reduce the memory size of the system. This is accomplished 851 by allocating pages of memory and put them "on hold". This only 852 makes sense for a system running under VM where the unused pages 853 will be reused by VM for other guest systems. The interface 854 allows an external monitor to balance memory of many systems. 855 Everybody who wants to run Linux under VM should select this 856 option. 857 858config CMM_IUCV 859 def_bool y 860 prompt "IUCV special message interface to cooperative memory management" 861 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 862 help 863 Select this option to enable the special message interface to 864 the cooperative memory management. 865 866config APPLDATA_BASE 867 def_bool n 868 prompt "Linux - VM Monitor Stream, base infrastructure" 869 depends on PROC_SYSCTL 870 help 871 This provides a kernel interface for creating and updating z/VM APPLDATA 872 monitor records. The monitor records are updated at certain time 873 intervals, once the timer is started. 874 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 875 i.e. enables or disables monitoring on the Linux side. 876 A custom interval value (in seconds) can be written to 877 /proc/appldata/interval. 878 879 Defaults are 60 seconds interval and timer off. 880 The /proc entries can also be read from, showing the current settings. 881 882config APPLDATA_MEM 883 def_tristate m 884 prompt "Monitor memory management statistics" 885 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 886 help 887 This provides memory management related data to the Linux - VM Monitor 888 Stream, like paging/swapping rate, memory utilisation, etc. 889 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 890 APPLDATA monitor record, i.e. enables or disables monitoring this record 891 on the z/VM side. 892 893 Default is disabled. 894 The /proc entry can also be read from, showing the current settings. 895 896 This can also be compiled as a module, which will be called 897 appldata_mem.o. 898 899config APPLDATA_OS 900 def_tristate m 901 prompt "Monitor OS statistics" 902 depends on APPLDATA_BASE 903 help 904 This provides OS related data to the Linux - VM Monitor Stream, like 905 CPU utilisation, etc. 906 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 907 APPLDATA monitor record, i.e. enables or disables monitoring this record 908 on the z/VM side. 909 910 Default is disabled. 911 This can also be compiled as a module, which will be called 912 appldata_os.o. 913 914config APPLDATA_NET_SUM 915 def_tristate m 916 prompt "Monitor overall network statistics" 917 depends on APPLDATA_BASE && NET 918 help 919 This provides network related data to the Linux - VM Monitor Stream, 920 currently there is only a total sum of network I/O statistics, no 921 per-interface data. 922 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 923 APPLDATA monitor record, i.e. enables or disables monitoring this record 924 on the z/VM side. 925 926 Default is disabled. 927 This can also be compiled as a module, which will be called 928 appldata_net_sum.o. 929 930config S390_HYPFS 931 def_bool y 932 prompt "s390 hypervisor information" 933 help 934 This provides several binary files at (debugfs)/s390_hypfs/ to 935 provide accounting information in an s390 hypervisor environment. 936 937config S390_HYPFS_FS 938 def_bool n 939 prompt "s390 hypervisor file system support" 940 select SYS_HYPERVISOR 941 depends on S390_HYPFS 942 help 943 This is a virtual file system intended to provide accounting 944 information in an s390 hypervisor environment. This file system 945 is deprecated and should not be used. 946 947 Say N if you are unsure. 948 949source "arch/s390/kvm/Kconfig" 950 951config S390_GUEST 952 def_bool y 953 prompt "s390 support for virtio devices" 954 select TTY 955 select VIRTUALIZATION 956 select VIRTIO 957 help 958 Enabling this option adds support for virtio based paravirtual device 959 drivers on s390. 960 961 Select this option if you want to run the kernel as a guest under 962 the KVM hypervisor. 963 964endmenu 965 966config S390_MODULES_SANITY_TEST_HELPERS 967 def_bool n 968 969menu "Selftests" 970 971config S390_UNWIND_SELFTEST 972 def_tristate n 973 depends on KUNIT 974 default KUNIT_ALL_TESTS 975 prompt "Test unwind functions" 976 help 977 This option enables s390 specific stack unwinder testing kernel 978 module. This option is not useful for distributions or general 979 kernels, but only for kernel developers working on architecture code. 980 981 Say N if you are unsure. 982 983config S390_KPROBES_SANITY_TEST 984 def_tristate n 985 prompt "Enable s390 specific kprobes tests" 986 depends on KPROBES 987 depends on KUNIT 988 help 989 This option enables an s390 specific kprobes test module. This option 990 is not useful for distributions or general kernels, but only for kernel 991 developers working on architecture code. 992 993 Say N if you are unsure. 994 995config S390_MODULES_SANITY_TEST 996 def_tristate n 997 depends on KUNIT 998 default KUNIT_ALL_TESTS 999 prompt "Enable s390 specific modules tests" 1000 select S390_MODULES_SANITY_TEST_HELPERS 1001 help 1002 This option enables an s390 specific modules test. This option is 1003 not useful for distributions or general kernels, but only for 1004 kernel developers working on architecture code. 1005 1006 Say N if you are unsure. 1007endmenu 1008