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