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 GENERIC_HWEIGHT 21 def_bool y 22 23config GENERIC_BUG 24 def_bool y if BUG 25 26config GENERIC_BUG_RELATIVE_POINTERS 27 def_bool y 28 29config GENERIC_LOCKBREAK 30 def_bool y if PREEMPTION 31 32config PGSTE 33 def_bool y if KVM 34 35config AUDIT_ARCH 36 def_bool y 37 38config NO_IOPORT_MAP 39 def_bool y 40 41config PCI_QUIRKS 42 def_bool n 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 S390 53 def_bool y 54 # 55 # Note: keep this list sorted alphabetically 56 # 57 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 58 select ALTERNATE_USER_ADDRESS_SPACE 59 select ARCH_32BIT_USTAT_F_TINODE 60 select ARCH_BINFMT_ELF_STATE 61 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 62 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 63 select ARCH_ENABLE_MEMORY_HOTREMOVE 64 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 65 select ARCH_HAS_CURRENT_STACK_POINTER 66 select ARCH_HAS_DEBUG_VM_PGTABLE 67 select ARCH_HAS_DEBUG_WX 68 select ARCH_HAS_DEVMEM_IS_ALLOWED 69 select ARCH_HAS_ELF_RANDOMIZE 70 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 71 select ARCH_HAS_FORTIFY_SOURCE 72 select ARCH_HAS_GCOV_PROFILE_ALL 73 select ARCH_HAS_GIGANTIC_PAGE 74 select ARCH_HAS_KCOV 75 select ARCH_HAS_MEMBARRIER_SYNC_CORE 76 select ARCH_HAS_MEM_ENCRYPT 77 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 78 select ARCH_HAS_PTE_SPECIAL 79 select ARCH_HAS_SCALED_CPUTIME 80 select ARCH_HAS_SET_DIRECT_MAP 81 select ARCH_HAS_SET_MEMORY 82 select ARCH_HAS_STRICT_KERNEL_RWX 83 select ARCH_HAS_STRICT_MODULE_RWX 84 select ARCH_HAS_SYSCALL_WRAPPER 85 select ARCH_HAS_UBSAN 86 select ARCH_HAS_VDSO_DATA 87 select ARCH_HAVE_NMI_SAFE_CMPXCHG 88 select ARCH_INLINE_READ_LOCK 89 select ARCH_INLINE_READ_LOCK_BH 90 select ARCH_INLINE_READ_LOCK_IRQ 91 select ARCH_INLINE_READ_LOCK_IRQSAVE 92 select ARCH_INLINE_READ_TRYLOCK 93 select ARCH_INLINE_READ_UNLOCK 94 select ARCH_INLINE_READ_UNLOCK_BH 95 select ARCH_INLINE_READ_UNLOCK_IRQ 96 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 97 select ARCH_INLINE_SPIN_LOCK 98 select ARCH_INLINE_SPIN_LOCK_BH 99 select ARCH_INLINE_SPIN_LOCK_IRQ 100 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 101 select ARCH_INLINE_SPIN_TRYLOCK 102 select ARCH_INLINE_SPIN_TRYLOCK_BH 103 select ARCH_INLINE_SPIN_UNLOCK 104 select ARCH_INLINE_SPIN_UNLOCK_BH 105 select ARCH_INLINE_SPIN_UNLOCK_IRQ 106 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 107 select ARCH_INLINE_WRITE_LOCK 108 select ARCH_INLINE_WRITE_LOCK_BH 109 select ARCH_INLINE_WRITE_LOCK_IRQ 110 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 111 select ARCH_INLINE_WRITE_TRYLOCK 112 select ARCH_INLINE_WRITE_UNLOCK 113 select ARCH_INLINE_WRITE_UNLOCK_BH 114 select ARCH_INLINE_WRITE_UNLOCK_IRQ 115 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 116 select ARCH_STACKWALK 117 select ARCH_SUPPORTS_ATOMIC_RMW 118 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 119 select ARCH_SUPPORTS_HUGETLBFS 120 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG 121 select ARCH_SUPPORTS_NUMA_BALANCING 122 select ARCH_SUPPORTS_PER_VMA_LOCK 123 select ARCH_USE_BUILTIN_BSWAP 124 select ARCH_USE_CMPXCHG_LOCKREF 125 select ARCH_USE_SYM_ANNOTATIONS 126 select ARCH_WANTS_NO_INSTR 127 select ARCH_WANT_DEFAULT_BPF_JIT 128 select ARCH_WANT_IPC_PARSE_VERSION 129 select ARCH_WANT_KERNEL_PMD_MKWRITE 130 select ARCH_WANT_LD_ORPHAN_WARN 131 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 132 select BUILDTIME_TABLE_SORT 133 select CLONE_BACKWARDS2 134 select DCACHE_WORD_ACCESS if !KMSAN 135 select DMA_OPS if PCI 136 select DYNAMIC_FTRACE if FUNCTION_TRACER 137 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 138 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 139 select GENERIC_ALLOCATOR 140 select GENERIC_CPU_AUTOPROBE 141 select GENERIC_CPU_VULNERABILITIES 142 select GENERIC_ENTRY 143 select GENERIC_GETTIMEOFDAY 144 select GENERIC_PTDUMP 145 select GENERIC_SMP_IDLE_THREAD 146 select GENERIC_TIME_VSYSCALL 147 select GENERIC_VDSO_TIME_NS 148 select GENERIC_IOREMAP if PCI 149 select HAVE_ALIGNED_STRUCT_PAGE 150 select HAVE_ARCH_AUDITSYSCALL 151 select HAVE_ARCH_JUMP_LABEL 152 select HAVE_ARCH_JUMP_LABEL_RELATIVE 153 select HAVE_ARCH_KASAN 154 select HAVE_ARCH_KASAN_VMALLOC 155 select HAVE_ARCH_KCSAN 156 select HAVE_ARCH_KFENCE 157 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 158 select HAVE_ARCH_SECCOMP_FILTER 159 select HAVE_ARCH_SOFT_DIRTY 160 select HAVE_ARCH_STACKLEAK 161 select HAVE_ARCH_TRACEHOOK 162 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 163 select HAVE_ARCH_VMAP_STACK 164 select HAVE_ASM_MODVERSIONS 165 select HAVE_CMPXCHG_DOUBLE 166 select HAVE_CMPXCHG_LOCAL 167 select HAVE_DEBUG_KMEMLEAK 168 select HAVE_DMA_CONTIGUOUS 169 select HAVE_DYNAMIC_FTRACE 170 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 171 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 172 select HAVE_DYNAMIC_FTRACE_WITH_REGS 173 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 174 select HAVE_EFFICIENT_UNALIGNED_ACCESS 175 select HAVE_FAST_GUP 176 select HAVE_FENTRY 177 select HAVE_FTRACE_MCOUNT_RECORD 178 select HAVE_FUNCTION_ARG_ACCESS_API 179 select HAVE_FUNCTION_ERROR_INJECTION 180 select HAVE_FUNCTION_GRAPH_RETVAL 181 select HAVE_FUNCTION_GRAPH_TRACER 182 select HAVE_FUNCTION_TRACER 183 select HAVE_GCC_PLUGINS 184 select HAVE_GENERIC_VDSO 185 select HAVE_IOREMAP_PROT if PCI 186 select HAVE_KERNEL_BZIP2 187 select HAVE_KERNEL_GZIP 188 select HAVE_KERNEL_LZ4 189 select HAVE_KERNEL_LZMA 190 select HAVE_KERNEL_LZO 191 select HAVE_KERNEL_UNCOMPRESSED 192 select HAVE_KERNEL_XZ 193 select HAVE_KERNEL_ZSTD 194 select HAVE_KPROBES 195 select HAVE_KPROBES_ON_FTRACE 196 select HAVE_KRETPROBES 197 select HAVE_KVM 198 select HAVE_LIVEPATCH 199 select HAVE_MEMBLOCK_PHYS_MAP 200 select HAVE_MOD_ARCH_SPECIFIC 201 select HAVE_NMI 202 select HAVE_NOP_MCOUNT 203 select HAVE_PAGE_SIZE_4KB 204 select HAVE_PCI 205 select HAVE_PERF_EVENTS 206 select HAVE_PERF_REGS 207 select HAVE_PERF_USER_STACK_DUMP 208 select HAVE_REGS_AND_STACK_ACCESS_API 209 select HAVE_RELIABLE_STACKTRACE 210 select HAVE_RETHOOK 211 select HAVE_RSEQ 212 select HAVE_SAMPLE_FTRACE_DIRECT 213 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 214 select HAVE_SETUP_PER_CPU_AREA 215 select HAVE_SOFTIRQ_ON_OWN_STACK 216 select HAVE_SYSCALL_TRACEPOINTS 217 select HAVE_VIRT_CPU_ACCOUNTING 218 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 219 select IOMMU_HELPER if PCI 220 select IOMMU_SUPPORT if PCI 221 select MMU_GATHER_MERGE_VMAS 222 select MMU_GATHER_NO_GATHER 223 select MMU_GATHER_RCU_TABLE_FREE 224 select MODULES_USE_ELF_RELA 225 select NEED_DMA_MAP_STATE if PCI 226 select NEED_PER_CPU_EMBED_FIRST_CHUNK 227 select NEED_SG_DMA_LENGTH if PCI 228 select OLD_SIGACTION 229 select OLD_SIGSUSPEND3 230 select PCI_DOMAINS if PCI 231 select PCI_MSI if PCI 232 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 233 select SPARSE_IRQ 234 select SWIOTLB 235 select SYSCTL_EXCEPTION_TRACE 236 select THREAD_INFO_IN_TASK 237 select TRACE_IRQFLAGS_SUPPORT 238 select TTY 239 select USER_STACKTRACE_SUPPORT 240 select VIRT_CPU_ACCOUNTING 241 select ZONE_DMA 242 # Note: keep the above list sorted alphabetically 243 244config SCHED_OMIT_FRAME_POINTER 245 def_bool y 246 247config PGTABLE_LEVELS 248 int 249 default 5 250 251source "kernel/livepatch/Kconfig" 252 253config ARCH_SUPPORTS_KEXEC 254 def_bool y 255 256config ARCH_SUPPORTS_KEXEC_FILE 257 def_bool y 258 259config ARCH_SUPPORTS_KEXEC_SIG 260 def_bool MODULE_SIG_FORMAT 261 262config ARCH_SUPPORTS_KEXEC_PURGATORY 263 def_bool y 264 265config ARCH_SUPPORTS_CRASH_DUMP 266 def_bool y 267 help 268 Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this. 269 This option also enables s390 zfcpdump. 270 See also <file:Documentation/arch/s390/zfcpdump.rst> 271 272menu "Processor type and features" 273 274config HAVE_MARCH_Z10_FEATURES 275 def_bool n 276 277config HAVE_MARCH_Z196_FEATURES 278 def_bool n 279 select HAVE_MARCH_Z10_FEATURES 280 281config HAVE_MARCH_ZEC12_FEATURES 282 def_bool n 283 select HAVE_MARCH_Z196_FEATURES 284 285config HAVE_MARCH_Z13_FEATURES 286 def_bool n 287 select HAVE_MARCH_ZEC12_FEATURES 288 289config HAVE_MARCH_Z14_FEATURES 290 def_bool n 291 select HAVE_MARCH_Z13_FEATURES 292 293config HAVE_MARCH_Z15_FEATURES 294 def_bool n 295 select HAVE_MARCH_Z14_FEATURES 296 297config HAVE_MARCH_Z16_FEATURES 298 def_bool n 299 select HAVE_MARCH_Z15_FEATURES 300 301choice 302 prompt "Processor type" 303 default MARCH_Z196 304 305config MARCH_Z10 306 bool "IBM System z10" 307 select HAVE_MARCH_Z10_FEATURES 308 depends on $(cc-option,-march=z10) 309 help 310 Select this to enable optimizations for IBM System z10 (2097 and 2098 311 series). This is the oldest machine generation currently supported. 312 313config MARCH_Z196 314 bool "IBM zEnterprise 114 and 196" 315 select HAVE_MARCH_Z196_FEATURES 316 depends on $(cc-option,-march=z196) 317 help 318 Select this to enable optimizations for IBM zEnterprise 114 and 196 319 (2818 and 2817 series). The kernel will be slightly faster but will 320 not work on older machines. 321 322config MARCH_ZEC12 323 bool "IBM zBC12 and zEC12" 324 select HAVE_MARCH_ZEC12_FEATURES 325 depends on $(cc-option,-march=zEC12) 326 help 327 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 328 2827 series). The kernel will be slightly faster but will not work on 329 older machines. 330 331config MARCH_Z13 332 bool "IBM z13s and z13" 333 select HAVE_MARCH_Z13_FEATURES 334 depends on $(cc-option,-march=z13) 335 help 336 Select this to enable optimizations for IBM z13s and z13 (2965 and 337 2964 series). The kernel will be slightly faster but will not work on 338 older machines. 339 340config MARCH_Z14 341 bool "IBM z14 ZR1 and z14" 342 select HAVE_MARCH_Z14_FEATURES 343 depends on $(cc-option,-march=z14) 344 help 345 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 346 and 3906 series). The kernel will be slightly faster but will not 347 work on older machines. 348 349config MARCH_Z15 350 bool "IBM z15" 351 select HAVE_MARCH_Z15_FEATURES 352 depends on $(cc-option,-march=z15) 353 help 354 Select this to enable optimizations for IBM z15 (8562 355 and 8561 series). The kernel will be slightly faster but will not 356 work on older machines. 357 358config MARCH_Z16 359 bool "IBM z16" 360 select HAVE_MARCH_Z16_FEATURES 361 depends on $(cc-option,-march=z16) 362 help 363 Select this to enable optimizations for IBM z16 (3931 and 364 3932 series). 365 366endchoice 367 368config MARCH_Z10_TUNE 369 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 370 371config MARCH_Z196_TUNE 372 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 373 374config MARCH_ZEC12_TUNE 375 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 376 377config MARCH_Z13_TUNE 378 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 379 380config MARCH_Z14_TUNE 381 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 382 383config MARCH_Z15_TUNE 384 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 385 386config MARCH_Z16_TUNE 387 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 388 389choice 390 prompt "Tune code generation" 391 default TUNE_DEFAULT 392 help 393 Cause the compiler to tune (-mtune) the generated code for a machine. 394 This will make the code run faster on the selected machine but 395 somewhat slower on other machines. 396 This option only changes how the compiler emits instructions, not the 397 selection of instructions itself, so the resulting kernel will run on 398 all other machines. 399 400config TUNE_DEFAULT 401 bool "Default" 402 help 403 Tune the generated code for the target processor for which the kernel 404 will be compiled. 405 406config TUNE_Z10 407 bool "IBM System z10" 408 409config TUNE_Z196 410 bool "IBM zEnterprise 114 and 196" 411 depends on $(cc-option,-mtune=z196) 412 413config TUNE_ZEC12 414 bool "IBM zBC12 and zEC12" 415 depends on $(cc-option,-mtune=zEC12) 416 417config TUNE_Z13 418 bool "IBM z13s and z13" 419 depends on $(cc-option,-mtune=z13) 420 421config TUNE_Z14 422 bool "IBM z14 ZR1 and z14" 423 depends on $(cc-option,-mtune=z14) 424 425config TUNE_Z15 426 bool "IBM z15" 427 depends on $(cc-option,-mtune=z15) 428 429config TUNE_Z16 430 bool "IBM z16" 431 depends on $(cc-option,-mtune=z16) 432 433endchoice 434 435config 64BIT 436 def_bool y 437 438config COMMAND_LINE_SIZE 439 int "Maximum size of kernel command line" 440 default 4096 441 range 896 1048576 442 help 443 This allows you to specify the maximum length of the kernel command 444 line. 445 446config COMPAT 447 def_bool n 448 prompt "Kernel support for 31 bit emulation" 449 select ARCH_WANT_OLD_COMPAT_IPC 450 select COMPAT_OLD_SIGACTION 451 select HAVE_UID16 452 depends on MULTIUSER 453 depends on !CC_IS_CLANG && !LD_IS_LLD 454 help 455 Select this option if you want to enable your system kernel to 456 handle system-calls from ELF binaries for 31 bit ESA. This option 457 (and some other stuff like libraries and such) is needed for 458 executing 31 bit applications. 459 460 If unsure say N. 461 462config SMP 463 def_bool y 464 465config NR_CPUS 466 int "Maximum number of CPUs (2-512)" 467 range 2 512 468 default "64" 469 help 470 This allows you to specify the maximum number of CPUs which this 471 kernel will support. The maximum supported value is 512 and the 472 minimum value which makes sense is 2. 473 474 This is purely to save memory - each supported CPU adds 475 approximately sixteen kilobytes to the kernel image. 476 477config HOTPLUG_CPU 478 def_bool y 479 480config NUMA 481 bool "NUMA support" 482 depends on SCHED_TOPOLOGY 483 default n 484 help 485 Enable NUMA support 486 487 This option adds NUMA support to the kernel. 488 489config NODES_SHIFT 490 int 491 depends on NUMA 492 default "1" 493 494config SCHED_SMT 495 def_bool n 496 497config SCHED_MC 498 def_bool n 499 500config SCHED_TOPOLOGY 501 def_bool y 502 prompt "Topology scheduler support" 503 select SCHED_SMT 504 select SCHED_MC 505 help 506 Topology scheduler support improves the CPU scheduler's decision 507 making when dealing with machines that have multi-threading, 508 multiple cores or multiple books. 509 510source "kernel/Kconfig.hz" 511 512config CERT_STORE 513 bool "Get user certificates via DIAG320" 514 depends on KEYS 515 select CRYPTO_LIB_SHA256 516 help 517 Enable this option if you want to access user-provided secure boot 518 certificates via DIAG 0x320. 519 520 These certificates will be made available via the keyring named 521 'cert_store'. 522 523config KERNEL_NOBP 524 def_bool n 525 prompt "Enable modified branch prediction for the kernel by default" 526 help 527 If this option is selected the kernel will switch to a modified 528 branch prediction mode if the firmware interface is available. 529 The modified branch prediction mode improves the behaviour in 530 regard to speculative execution. 531 532 With the option enabled the kernel parameter "nobp=0" or "nospec" 533 can be used to run the kernel in the normal branch prediction mode. 534 535 With the option disabled the modified branch prediction mode is 536 enabled with the "nobp=1" kernel parameter. 537 538 If unsure, say N. 539 540config EXPOLINE 541 def_bool n 542 depends on $(cc-option,-mindirect-branch=thunk) 543 prompt "Avoid speculative indirect branches in the kernel" 544 help 545 Compile the kernel with the expoline compiler options to guard 546 against kernel-to-user data leaks by avoiding speculative indirect 547 branches. 548 Requires a compiler with -mindirect-branch=thunk support for full 549 protection. The kernel may run slower. 550 551 If unsure, say N. 552 553config EXPOLINE_EXTERN 554 def_bool n 555 depends on EXPOLINE 556 depends on CC_IS_GCC && GCC_VERSION >= 110200 557 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 558 prompt "Generate expolines as extern functions." 559 help 560 This option is required for some tooling like kpatch. The kernel is 561 compiled with -mindirect-branch=thunk-extern and requires a newer 562 compiler. 563 564 If unsure, say N. 565 566choice 567 prompt "Expoline default" 568 depends on EXPOLINE 569 default EXPOLINE_FULL 570 571config EXPOLINE_OFF 572 bool "spectre_v2=off" 573 574config EXPOLINE_AUTO 575 bool "spectre_v2=auto" 576 577config EXPOLINE_FULL 578 bool "spectre_v2=on" 579 580endchoice 581 582config RELOCATABLE 583 def_bool y 584 help 585 This builds a kernel image that retains relocation information 586 so it can be loaded at an arbitrary address. 587 The relocations make the kernel image about 15% larger (compressed 588 10%), but are discarded at runtime. 589 Note: this option exists only for documentation purposes, please do 590 not remove it. 591 592config PIE_BUILD 593 def_bool CC_IS_CLANG && !$(cc-option,-munaligned-symbols) 594 help 595 If the compiler is unable to generate code that can manage unaligned 596 symbols, the kernel is linked as a position-independent executable 597 (PIE) and includes dynamic relocations that are processed early 598 during bootup. 599 600 For kpatch functionality, it is recommended to build the kernel 601 without the PIE_BUILD option. PIE_BUILD is only enabled when the 602 compiler lacks proper support for handling unaligned symbols. 603 604config RANDOMIZE_BASE 605 bool "Randomize the address of the kernel image (KASLR)" 606 default y 607 help 608 In support of Kernel Address Space Layout Randomization (KASLR), 609 this randomizes the address at which the kernel image is loaded, 610 as a security feature that deters exploit attempts relying on 611 knowledge of the location of kernel internals. 612 613endmenu 614 615menu "Memory setup" 616 617config ARCH_SPARSEMEM_ENABLE 618 def_bool y 619 select SPARSEMEM_VMEMMAP_ENABLE 620 select SPARSEMEM_VMEMMAP 621 622config ARCH_SPARSEMEM_DEFAULT 623 def_bool y 624 625config MAX_PHYSMEM_BITS 626 int "Maximum size of supported physical memory in bits (42-53)" 627 range 42 53 628 default "46" 629 help 630 This option specifies the maximum supported size of physical memory 631 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 632 Increasing the number of bits also increases the kernel image size. 633 By default 46 bits (64TB) are supported. 634 635config CHECK_STACK 636 def_bool y 637 depends on !VMAP_STACK 638 prompt "Detect kernel stack overflow" 639 help 640 This option enables the compiler option -mstack-guard and 641 -mstack-size if they are available. If the compiler supports them 642 it will emit additional code to each function prolog to trigger 643 an illegal operation if the kernel stack is about to overflow. 644 645 Say N if you are unsure. 646 647config STACK_GUARD 648 int "Size of the guard area (128-1024)" 649 range 128 1024 650 depends on CHECK_STACK 651 default "256" 652 help 653 This allows you to specify the size of the guard area at the lower 654 end of the kernel stack. If the kernel stack points into the guard 655 area on function entry an illegal operation is triggered. The size 656 needs to be a power of 2. Please keep in mind that the size of an 657 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 658 The minimum size for the stack guard should be 256 for 31 bit and 659 512 for 64 bit. 660 661endmenu 662 663menu "I/O subsystem" 664 665config QDIO 666 def_tristate y 667 prompt "QDIO support" 668 help 669 This driver provides the Queued Direct I/O base support for 670 IBM System z. 671 672 To compile this driver as a module, choose M here: the 673 module will be called qdio. 674 675 If unsure, say Y. 676 677if PCI 678 679config PCI_NR_FUNCTIONS 680 int "Maximum number of PCI functions (1-4096)" 681 range 1 4096 682 default "512" 683 help 684 This allows you to specify the maximum number of PCI functions which 685 this kernel will support. 686 687endif # PCI 688 689config HAS_IOMEM 690 def_bool PCI 691 692config CHSC_SCH 693 def_tristate m 694 prompt "Support for CHSC subchannels" 695 help 696 This driver allows usage of CHSC subchannels. A CHSC subchannel 697 is usually present on LPAR only. 698 The driver creates a device /dev/chsc, which may be used to 699 obtain I/O configuration information about the machine and 700 to issue asynchronous chsc commands (DANGEROUS). 701 You will usually only want to use this interface on a special 702 LPAR designated for system management. 703 704 To compile this driver as a module, choose M here: the 705 module will be called chsc_sch. 706 707 If unsure, say N. 708 709config SCM_BUS 710 def_bool y 711 prompt "SCM bus driver" 712 help 713 Bus driver for Storage Class Memory. 714 715config EADM_SCH 716 def_tristate m 717 prompt "Support for EADM subchannels" 718 depends on SCM_BUS 719 help 720 This driver allows usage of EADM subchannels. EADM subchannels act 721 as a communication vehicle for SCM increments. 722 723 To compile this driver as a module, choose M here: the 724 module will be called eadm_sch. 725 726config VFIO_CCW 727 def_tristate n 728 prompt "Support for VFIO-CCW subchannels" 729 depends on VFIO 730 select VFIO_MDEV 731 help 732 This driver allows usage of I/O subchannels via VFIO-CCW. 733 734 To compile this driver as a module, choose M here: the 735 module will be called vfio_ccw. 736 737config VFIO_AP 738 def_tristate n 739 prompt "VFIO support for AP devices" 740 depends on KVM 741 depends on VFIO 742 depends on ZCRYPT 743 select VFIO_MDEV 744 help 745 This driver grants access to Adjunct Processor (AP) devices 746 via the VFIO mediated device interface. 747 748 To compile this driver as a module, choose M here: the module 749 will be called vfio_ap. 750 751endmenu 752 753config CCW 754 def_bool y 755 756config HAVE_PNETID 757 tristate 758 default (SMC || CCWGROUP) 759 760menu "Virtualization" 761 762config PROTECTED_VIRTUALIZATION_GUEST 763 def_bool n 764 prompt "Protected virtualization guest support" 765 help 766 Select this option, if you want to be able to run this 767 kernel as a protected virtualization KVM guest. 768 Protected virtualization capable machines have a mini hypervisor 769 located at machine level (an ultravisor). With help of the 770 Ultravisor, KVM will be able to run "protected" VMs, special 771 VMs whose memory and management data are unavailable to KVM. 772 773config PFAULT 774 def_bool y 775 prompt "Pseudo page fault support" 776 help 777 Select this option, if you want to use PFAULT pseudo page fault 778 handling under VM. If running native or in LPAR, this option 779 has no effect. If your VM does not support PFAULT, PAGEEX 780 pseudo page fault handling will be used. 781 Note that VM 4.2 supports PFAULT but has a bug in its 782 implementation that causes some problems. 783 Everybody who wants to run Linux under VM != VM4.2 should select 784 this option. 785 786config CMM 787 def_tristate n 788 prompt "Cooperative memory management" 789 help 790 Select this option, if you want to enable the kernel interface 791 to reduce the memory size of the system. This is accomplished 792 by allocating pages of memory and put them "on hold". This only 793 makes sense for a system running under VM where the unused pages 794 will be reused by VM for other guest systems. The interface 795 allows an external monitor to balance memory of many systems. 796 Everybody who wants to run Linux under VM should select this 797 option. 798 799config CMM_IUCV 800 def_bool y 801 prompt "IUCV special message interface to cooperative memory management" 802 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 803 help 804 Select this option to enable the special message interface to 805 the cooperative memory management. 806 807config APPLDATA_BASE 808 def_bool n 809 prompt "Linux - VM Monitor Stream, base infrastructure" 810 depends on PROC_SYSCTL 811 help 812 This provides a kernel interface for creating and updating z/VM APPLDATA 813 monitor records. The monitor records are updated at certain time 814 intervals, once the timer is started. 815 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 816 i.e. enables or disables monitoring on the Linux side. 817 A custom interval value (in seconds) can be written to 818 /proc/appldata/interval. 819 820 Defaults are 60 seconds interval and timer off. 821 The /proc entries can also be read from, showing the current settings. 822 823config APPLDATA_MEM 824 def_tristate m 825 prompt "Monitor memory management statistics" 826 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 827 help 828 This provides memory management related data to the Linux - VM Monitor 829 Stream, like paging/swapping rate, memory utilisation, etc. 830 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 831 APPLDATA monitor record, i.e. enables or disables monitoring this record 832 on the z/VM side. 833 834 Default is disabled. 835 The /proc entry can also be read from, showing the current settings. 836 837 This can also be compiled as a module, which will be called 838 appldata_mem.o. 839 840config APPLDATA_OS 841 def_tristate m 842 prompt "Monitor OS statistics" 843 depends on APPLDATA_BASE 844 help 845 This provides OS related data to the Linux - VM Monitor Stream, like 846 CPU utilisation, etc. 847 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 848 APPLDATA monitor record, i.e. enables or disables monitoring this record 849 on the z/VM side. 850 851 Default is disabled. 852 This can also be compiled as a module, which will be called 853 appldata_os.o. 854 855config APPLDATA_NET_SUM 856 def_tristate m 857 prompt "Monitor overall network statistics" 858 depends on APPLDATA_BASE && NET 859 help 860 This provides network related data to the Linux - VM Monitor Stream, 861 currently there is only a total sum of network I/O statistics, no 862 per-interface data. 863 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 864 APPLDATA monitor record, i.e. enables or disables monitoring this record 865 on the z/VM side. 866 867 Default is disabled. 868 This can also be compiled as a module, which will be called 869 appldata_net_sum.o. 870 871config S390_HYPFS 872 def_bool y 873 prompt "s390 hypervisor information" 874 help 875 This provides several binary files at (debugfs)/s390_hypfs/ to 876 provide accounting information in an s390 hypervisor environment. 877 878config S390_HYPFS_FS 879 def_bool n 880 prompt "s390 hypervisor file system support" 881 select SYS_HYPERVISOR 882 depends on S390_HYPFS 883 help 884 This is a virtual file system intended to provide accounting 885 information in an s390 hypervisor environment. This file system 886 is deprecated and should not be used. 887 888 Say N if you are unsure. 889 890source "arch/s390/kvm/Kconfig" 891 892config S390_GUEST 893 def_bool y 894 prompt "s390 support for virtio devices" 895 select TTY 896 select VIRTUALIZATION 897 select VIRTIO 898 help 899 Enabling this option adds support for virtio based paravirtual device 900 drivers on s390. 901 902 Select this option if you want to run the kernel as a guest under 903 the KVM hypervisor. 904 905endmenu 906 907config S390_MODULES_SANITY_TEST_HELPERS 908 def_bool n 909 910menu "Selftests" 911 912config S390_UNWIND_SELFTEST 913 def_tristate n 914 depends on KUNIT 915 default KUNIT_ALL_TESTS 916 prompt "Test unwind functions" 917 help 918 This option enables s390 specific stack unwinder testing kernel 919 module. This option is not useful for distributions or general 920 kernels, but only for kernel developers working on architecture code. 921 922 Say N if you are unsure. 923 924config S390_KPROBES_SANITY_TEST 925 def_tristate n 926 prompt "Enable s390 specific kprobes tests" 927 depends on KPROBES 928 depends on KUNIT 929 help 930 This option enables an s390 specific kprobes test module. This option 931 is not useful for distributions or general kernels, but only for kernel 932 developers working on architecture code. 933 934 Say N if you are unsure. 935 936config S390_MODULES_SANITY_TEST 937 def_tristate n 938 depends on KUNIT 939 default KUNIT_ALL_TESTS 940 prompt "Enable s390 specific modules tests" 941 select S390_MODULES_SANITY_TEST_HELPERS 942 help 943 This option enables an s390 specific modules test. This option is 944 not useful for distributions or general kernels, but only for 945 kernel developers working on architecture code. 946 947 Say N if you are unsure. 948endmenu 949