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_SANITIZE_ALL 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_DYNAMIC_TASK_STRUCT 127 select ARCH_WANTS_NO_INSTR 128 select ARCH_WANT_DEFAULT_BPF_JIT 129 select ARCH_WANT_IPC_PARSE_VERSION 130 select ARCH_WANT_KERNEL_PMD_MKWRITE 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 if SLUB 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_PCI 204 select HAVE_PERF_EVENTS 205 select HAVE_PERF_REGS 206 select HAVE_PERF_USER_STACK_DUMP 207 select HAVE_REGS_AND_STACK_ACCESS_API 208 select HAVE_RELIABLE_STACKTRACE 209 select HAVE_RETHOOK 210 select HAVE_RSEQ 211 select HAVE_SAMPLE_FTRACE_DIRECT 212 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 213 select HAVE_SETUP_PER_CPU_AREA 214 select HAVE_SOFTIRQ_ON_OWN_STACK 215 select HAVE_SYSCALL_TRACEPOINTS 216 select HAVE_VIRT_CPU_ACCOUNTING 217 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 218 select IOMMU_HELPER if PCI 219 select IOMMU_SUPPORT if PCI 220 select KEXEC 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 CRYPTO && CRYPTO_SHA256 && CRYPTO_SHA256_S390 258 259config ARCH_SUPPORTS_KEXEC_SIG 260 def_bool MODULE_SIG_FORMAT 261 262config ARCH_SUPPORTS_KEXEC_PURGATORY 263 def_bool KEXEC_FILE 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 y 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 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. It is safe to say "Y". 459 460config SMP 461 def_bool y 462 463config NR_CPUS 464 int "Maximum number of CPUs (2-512)" 465 range 2 512 466 default "64" 467 help 468 This allows you to specify the maximum number of CPUs which this 469 kernel will support. The maximum supported value is 512 and the 470 minimum value which makes sense is 2. 471 472 This is purely to save memory - each supported CPU adds 473 approximately sixteen kilobytes to the kernel image. 474 475config HOTPLUG_CPU 476 def_bool y 477 478config NUMA 479 bool "NUMA support" 480 depends on SCHED_TOPOLOGY 481 default n 482 help 483 Enable NUMA support 484 485 This option adds NUMA support to the kernel. 486 487config NODES_SHIFT 488 int 489 depends on NUMA 490 default "1" 491 492config SCHED_SMT 493 def_bool n 494 495config SCHED_MC 496 def_bool n 497 498config SCHED_TOPOLOGY 499 def_bool y 500 prompt "Topology scheduler support" 501 select SCHED_SMT 502 select SCHED_MC 503 help 504 Topology scheduler support improves the CPU scheduler's decision 505 making when dealing with machines that have multi-threading, 506 multiple cores or multiple books. 507 508source "kernel/Kconfig.hz" 509 510config CERT_STORE 511 bool "Get user certificates via DIAG320" 512 depends on KEYS 513 select CRYPTO_LIB_SHA256 514 help 515 Enable this option if you want to access user-provided secure boot 516 certificates via DIAG 0x320. 517 518 These certificates will be made available via the keyring named 519 'cert_store'. 520 521config KERNEL_NOBP 522 def_bool n 523 prompt "Enable modified branch prediction for the kernel by default" 524 help 525 If this option is selected the kernel will switch to a modified 526 branch prediction mode if the firmware interface is available. 527 The modified branch prediction mode improves the behaviour in 528 regard to speculative execution. 529 530 With the option enabled the kernel parameter "nobp=0" or "nospec" 531 can be used to run the kernel in the normal branch prediction mode. 532 533 With the option disabled the modified branch prediction mode is 534 enabled with the "nobp=1" kernel parameter. 535 536 If unsure, say N. 537 538config EXPOLINE 539 def_bool n 540 depends on $(cc-option,-mindirect-branch=thunk) 541 prompt "Avoid speculative indirect branches in the kernel" 542 help 543 Compile the kernel with the expoline compiler options to guard 544 against kernel-to-user data leaks by avoiding speculative indirect 545 branches. 546 Requires a compiler with -mindirect-branch=thunk support for full 547 protection. The kernel may run slower. 548 549 If unsure, say N. 550 551config EXPOLINE_EXTERN 552 def_bool n 553 depends on EXPOLINE 554 depends on CC_IS_GCC && GCC_VERSION >= 110200 555 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 556 prompt "Generate expolines as extern functions." 557 help 558 This option is required for some tooling like kpatch. The kernel is 559 compiled with -mindirect-branch=thunk-extern and requires a newer 560 compiler. 561 562 If unsure, say N. 563 564choice 565 prompt "Expoline default" 566 depends on EXPOLINE 567 default EXPOLINE_FULL 568 569config EXPOLINE_OFF 570 bool "spectre_v2=off" 571 572config EXPOLINE_AUTO 573 bool "spectre_v2=auto" 574 575config EXPOLINE_FULL 576 bool "spectre_v2=on" 577 578endchoice 579 580config RELOCATABLE 581 def_bool y 582 help 583 This builds a kernel image that retains relocation information 584 so it can be loaded at an arbitrary address. 585 The kernel is linked as a position-independent executable (PIE) 586 and contains dynamic relocations which are processed early in the 587 bootup process. 588 The relocations make the kernel image about 15% larger (compressed 589 10%), but are discarded at runtime. 590 Note: this option exists only for documentation purposes, please do 591 not remove it. 592 593config RANDOMIZE_BASE 594 bool "Randomize the address of the kernel image (KASLR)" 595 default y 596 help 597 In support of Kernel Address Space Layout Randomization (KASLR), 598 this randomizes the address at which the kernel image is loaded, 599 as a security feature that deters exploit attempts relying on 600 knowledge of the location of kernel internals. 601 602endmenu 603 604menu "Memory setup" 605 606config ARCH_SPARSEMEM_ENABLE 607 def_bool y 608 select SPARSEMEM_VMEMMAP_ENABLE 609 select SPARSEMEM_VMEMMAP 610 611config ARCH_SPARSEMEM_DEFAULT 612 def_bool y 613 614config MAX_PHYSMEM_BITS 615 int "Maximum size of supported physical memory in bits (42-53)" 616 range 42 53 617 default "46" 618 help 619 This option specifies the maximum supported size of physical memory 620 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 621 Increasing the number of bits also increases the kernel image size. 622 By default 46 bits (64TB) are supported. 623 624config CHECK_STACK 625 def_bool y 626 depends on !VMAP_STACK 627 prompt "Detect kernel stack overflow" 628 help 629 This option enables the compiler option -mstack-guard and 630 -mstack-size if they are available. If the compiler supports them 631 it will emit additional code to each function prolog to trigger 632 an illegal operation if the kernel stack is about to overflow. 633 634 Say N if you are unsure. 635 636config STACK_GUARD 637 int "Size of the guard area (128-1024)" 638 range 128 1024 639 depends on CHECK_STACK 640 default "256" 641 help 642 This allows you to specify the size of the guard area at the lower 643 end of the kernel stack. If the kernel stack points into the guard 644 area on function entry an illegal operation is triggered. The size 645 needs to be a power of 2. Please keep in mind that the size of an 646 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 647 The minimum size for the stack guard should be 256 for 31 bit and 648 512 for 64 bit. 649 650endmenu 651 652menu "I/O subsystem" 653 654config QDIO 655 def_tristate y 656 prompt "QDIO support" 657 help 658 This driver provides the Queued Direct I/O base support for 659 IBM System z. 660 661 To compile this driver as a module, choose M here: the 662 module will be called qdio. 663 664 If unsure, say Y. 665 666if PCI 667 668config PCI_NR_FUNCTIONS 669 int "Maximum number of PCI functions (1-4096)" 670 range 1 4096 671 default "512" 672 help 673 This allows you to specify the maximum number of PCI functions which 674 this kernel will support. 675 676endif # PCI 677 678config HAS_IOMEM 679 def_bool PCI 680 681config CHSC_SCH 682 def_tristate m 683 prompt "Support for CHSC subchannels" 684 help 685 This driver allows usage of CHSC subchannels. A CHSC subchannel 686 is usually present on LPAR only. 687 The driver creates a device /dev/chsc, which may be used to 688 obtain I/O configuration information about the machine and 689 to issue asynchronous chsc commands (DANGEROUS). 690 You will usually only want to use this interface on a special 691 LPAR designated for system management. 692 693 To compile this driver as a module, choose M here: the 694 module will be called chsc_sch. 695 696 If unsure, say N. 697 698config SCM_BUS 699 def_bool y 700 prompt "SCM bus driver" 701 help 702 Bus driver for Storage Class Memory. 703 704config EADM_SCH 705 def_tristate m 706 prompt "Support for EADM subchannels" 707 depends on SCM_BUS 708 help 709 This driver allows usage of EADM subchannels. EADM subchannels act 710 as a communication vehicle for SCM increments. 711 712 To compile this driver as a module, choose M here: the 713 module will be called eadm_sch. 714 715config VFIO_CCW 716 def_tristate n 717 prompt "Support for VFIO-CCW subchannels" 718 depends on VFIO 719 select VFIO_MDEV 720 help 721 This driver allows usage of I/O subchannels via VFIO-CCW. 722 723 To compile this driver as a module, choose M here: the 724 module will be called vfio_ccw. 725 726config VFIO_AP 727 def_tristate n 728 prompt "VFIO support for AP devices" 729 depends on KVM 730 depends on VFIO 731 depends on ZCRYPT 732 select VFIO_MDEV 733 help 734 This driver grants access to Adjunct Processor (AP) devices 735 via the VFIO mediated device interface. 736 737 To compile this driver as a module, choose M here: the module 738 will be called vfio_ap. 739 740endmenu 741 742config CCW 743 def_bool y 744 745config HAVE_PNETID 746 tristate 747 default (SMC || CCWGROUP) 748 749menu "Virtualization" 750 751config PROTECTED_VIRTUALIZATION_GUEST 752 def_bool n 753 prompt "Protected virtualization guest support" 754 help 755 Select this option, if you want to be able to run this 756 kernel as a protected virtualization KVM guest. 757 Protected virtualization capable machines have a mini hypervisor 758 located at machine level (an ultravisor). With help of the 759 Ultravisor, KVM will be able to run "protected" VMs, special 760 VMs whose memory and management data are unavailable to KVM. 761 762config PFAULT 763 def_bool y 764 prompt "Pseudo page fault support" 765 help 766 Select this option, if you want to use PFAULT pseudo page fault 767 handling under VM. If running native or in LPAR, this option 768 has no effect. If your VM does not support PFAULT, PAGEEX 769 pseudo page fault handling will be used. 770 Note that VM 4.2 supports PFAULT but has a bug in its 771 implementation that causes some problems. 772 Everybody who wants to run Linux under VM != VM4.2 should select 773 this option. 774 775config CMM 776 def_tristate n 777 prompt "Cooperative memory management" 778 help 779 Select this option, if you want to enable the kernel interface 780 to reduce the memory size of the system. This is accomplished 781 by allocating pages of memory and put them "on hold". This only 782 makes sense for a system running under VM where the unused pages 783 will be reused by VM for other guest systems. The interface 784 allows an external monitor to balance memory of many systems. 785 Everybody who wants to run Linux under VM should select this 786 option. 787 788config CMM_IUCV 789 def_bool y 790 prompt "IUCV special message interface to cooperative memory management" 791 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 792 help 793 Select this option to enable the special message interface to 794 the cooperative memory management. 795 796config APPLDATA_BASE 797 def_bool n 798 prompt "Linux - VM Monitor Stream, base infrastructure" 799 depends on PROC_SYSCTL 800 help 801 This provides a kernel interface for creating and updating z/VM APPLDATA 802 monitor records. The monitor records are updated at certain time 803 intervals, once the timer is started. 804 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 805 i.e. enables or disables monitoring on the Linux side. 806 A custom interval value (in seconds) can be written to 807 /proc/appldata/interval. 808 809 Defaults are 60 seconds interval and timer off. 810 The /proc entries can also be read from, showing the current settings. 811 812config APPLDATA_MEM 813 def_tristate m 814 prompt "Monitor memory management statistics" 815 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 816 help 817 This provides memory management related data to the Linux - VM Monitor 818 Stream, like paging/swapping rate, memory utilisation, etc. 819 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 820 APPLDATA monitor record, i.e. enables or disables monitoring this record 821 on the z/VM side. 822 823 Default is disabled. 824 The /proc entry can also be read from, showing the current settings. 825 826 This can also be compiled as a module, which will be called 827 appldata_mem.o. 828 829config APPLDATA_OS 830 def_tristate m 831 prompt "Monitor OS statistics" 832 depends on APPLDATA_BASE 833 help 834 This provides OS related data to the Linux - VM Monitor Stream, like 835 CPU utilisation, etc. 836 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 837 APPLDATA monitor record, i.e. enables or disables monitoring this record 838 on the z/VM side. 839 840 Default is disabled. 841 This can also be compiled as a module, which will be called 842 appldata_os.o. 843 844config APPLDATA_NET_SUM 845 def_tristate m 846 prompt "Monitor overall network statistics" 847 depends on APPLDATA_BASE && NET 848 help 849 This provides network related data to the Linux - VM Monitor Stream, 850 currently there is only a total sum of network I/O statistics, no 851 per-interface data. 852 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 853 APPLDATA monitor record, i.e. enables or disables monitoring this record 854 on the z/VM side. 855 856 Default is disabled. 857 This can also be compiled as a module, which will be called 858 appldata_net_sum.o. 859 860config S390_HYPFS 861 def_bool y 862 prompt "s390 hypervisor information" 863 help 864 This provides several binary files at (debugfs)/s390_hypfs/ to 865 provide accounting information in an s390 hypervisor environment. 866 867config S390_HYPFS_FS 868 def_bool n 869 prompt "s390 hypervisor file system support" 870 select SYS_HYPERVISOR 871 depends on S390_HYPFS 872 help 873 This is a virtual file system intended to provide accounting 874 information in an s390 hypervisor environment. This file system 875 is deprecated and should not be used. 876 877 Say N if you are unsure. 878 879source "arch/s390/kvm/Kconfig" 880 881config S390_GUEST 882 def_bool y 883 prompt "s390 support for virtio devices" 884 select TTY 885 select VIRTUALIZATION 886 select VIRTIO 887 help 888 Enabling this option adds support for virtio based paravirtual device 889 drivers on s390. 890 891 Select this option if you want to run the kernel as a guest under 892 the KVM hypervisor. 893 894endmenu 895 896config S390_MODULES_SANITY_TEST_HELPERS 897 def_bool n 898 899menu "Selftests" 900 901config S390_UNWIND_SELFTEST 902 def_tristate n 903 depends on KUNIT 904 default KUNIT_ALL_TESTS 905 prompt "Test unwind functions" 906 help 907 This option enables s390 specific stack unwinder testing kernel 908 module. This option is not useful for distributions or general 909 kernels, but only for kernel developers working on architecture code. 910 911 Say N if you are unsure. 912 913config S390_KPROBES_SANITY_TEST 914 def_tristate n 915 prompt "Enable s390 specific kprobes tests" 916 depends on KPROBES 917 depends on KUNIT 918 help 919 This option enables an s390 specific kprobes test module. This option 920 is not useful for distributions or general kernels, but only for kernel 921 developers working on architecture code. 922 923 Say N if you are unsure. 924 925config S390_MODULES_SANITY_TEST 926 def_tristate n 927 depends on KUNIT 928 default KUNIT_ALL_TESTS 929 prompt "Enable s390 specific modules tests" 930 select S390_MODULES_SANITY_TEST_HELPERS 931 help 932 This option enables an s390 specific modules test. This option is 933 not useful for distributions or general kernels, but only for 934 kernel developers working on architecture code. 935 936 Say N if you are unsure. 937endmenu 938