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_NUMA_BALANCING 121 select ARCH_SUPPORTS_PER_VMA_LOCK 122 select ARCH_USE_BUILTIN_BSWAP 123 select ARCH_USE_CMPXCHG_LOCKREF 124 select ARCH_USE_SYM_ANNOTATIONS 125 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 126 select ARCH_WANTS_NO_INSTR 127 select ARCH_WANT_DEFAULT_BPF_JIT 128 select ARCH_WANT_IPC_PARSE_VERSION 129 select ARCH_WANT_OPTIMIZE_VMEMMAP 130 select BUILDTIME_TABLE_SORT 131 select CLONE_BACKWARDS2 132 select DMA_OPS if PCI 133 select DYNAMIC_FTRACE if FUNCTION_TRACER 134 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 135 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 136 select GENERIC_ALLOCATOR 137 select GENERIC_CPU_AUTOPROBE 138 select GENERIC_CPU_VULNERABILITIES 139 select GENERIC_ENTRY 140 select GENERIC_GETTIMEOFDAY 141 select GENERIC_PTDUMP 142 select GENERIC_SMP_IDLE_THREAD 143 select GENERIC_TIME_VSYSCALL 144 select GENERIC_VDSO_TIME_NS 145 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 146 select HAVE_ARCH_AUDITSYSCALL 147 select HAVE_ARCH_JUMP_LABEL 148 select HAVE_ARCH_JUMP_LABEL_RELATIVE 149 select HAVE_ARCH_KASAN 150 select HAVE_ARCH_KASAN_VMALLOC 151 select HAVE_ARCH_KCSAN 152 select HAVE_ARCH_KFENCE 153 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 154 select HAVE_ARCH_SECCOMP_FILTER 155 select HAVE_ARCH_SOFT_DIRTY 156 select HAVE_ARCH_STACKLEAK 157 select HAVE_ARCH_TRACEHOOK 158 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 159 select HAVE_ARCH_VMAP_STACK 160 select HAVE_ASM_MODVERSIONS 161 select HAVE_CMPXCHG_DOUBLE 162 select HAVE_CMPXCHG_LOCAL 163 select HAVE_DEBUG_KMEMLEAK 164 select HAVE_DMA_CONTIGUOUS 165 select HAVE_DYNAMIC_FTRACE 166 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 167 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 168 select HAVE_DYNAMIC_FTRACE_WITH_REGS 169 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 170 select HAVE_EFFICIENT_UNALIGNED_ACCESS 171 select HAVE_FAST_GUP 172 select HAVE_FENTRY 173 select HAVE_FTRACE_MCOUNT_RECORD 174 select HAVE_FUNCTION_ARG_ACCESS_API 175 select HAVE_FUNCTION_ERROR_INJECTION 176 select HAVE_FUNCTION_GRAPH_TRACER 177 select HAVE_FUNCTION_TRACER 178 select HAVE_GCC_PLUGINS 179 select HAVE_GENERIC_VDSO 180 select HAVE_IOREMAP_PROT if PCI 181 select HAVE_KERNEL_BZIP2 182 select HAVE_KERNEL_GZIP 183 select HAVE_KERNEL_LZ4 184 select HAVE_KERNEL_LZMA 185 select HAVE_KERNEL_LZO 186 select HAVE_KERNEL_UNCOMPRESSED 187 select HAVE_KERNEL_XZ 188 select HAVE_KERNEL_ZSTD 189 select HAVE_KPROBES 190 select HAVE_KPROBES_ON_FTRACE 191 select HAVE_KRETPROBES 192 select HAVE_KVM 193 select HAVE_LIVEPATCH 194 select HAVE_MEMBLOCK_PHYS_MAP 195 select HAVE_MOD_ARCH_SPECIFIC 196 select HAVE_NMI 197 select HAVE_NOP_MCOUNT 198 select HAVE_PCI 199 select HAVE_PERF_EVENTS 200 select HAVE_PERF_REGS 201 select HAVE_PERF_USER_STACK_DUMP 202 select HAVE_REGS_AND_STACK_ACCESS_API 203 select HAVE_RELIABLE_STACKTRACE 204 select HAVE_RETHOOK 205 select HAVE_RSEQ 206 select HAVE_SAMPLE_FTRACE_DIRECT 207 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 208 select HAVE_SETUP_PER_CPU_AREA 209 select HAVE_SOFTIRQ_ON_OWN_STACK 210 select HAVE_SYSCALL_TRACEPOINTS 211 select HAVE_VIRT_CPU_ACCOUNTING 212 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 213 select IOMMU_HELPER if PCI 214 select IOMMU_SUPPORT if PCI 215 select MMU_GATHER_MERGE_VMAS 216 select MMU_GATHER_NO_GATHER 217 select MMU_GATHER_RCU_TABLE_FREE 218 select MODULES_USE_ELF_RELA 219 select NEED_DMA_MAP_STATE if PCI 220 select NEED_PER_CPU_EMBED_FIRST_CHUNK 221 select NEED_SG_DMA_LENGTH if PCI 222 select OLD_SIGACTION 223 select OLD_SIGSUSPEND3 224 select PCI_DOMAINS if PCI 225 select PCI_MSI if PCI 226 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 227 select SPARSE_IRQ 228 select SWIOTLB 229 select SYSCTL_EXCEPTION_TRACE 230 select THREAD_INFO_IN_TASK 231 select TRACE_IRQFLAGS_SUPPORT 232 select TTY 233 select VIRT_CPU_ACCOUNTING 234 select ZONE_DMA 235 # Note: keep the above list sorted alphabetically 236 237config SCHED_OMIT_FRAME_POINTER 238 def_bool y 239 240config PGTABLE_LEVELS 241 int 242 default 5 243 244source "kernel/livepatch/Kconfig" 245 246menu "Processor type and features" 247 248config HAVE_MARCH_Z10_FEATURES 249 def_bool n 250 251config HAVE_MARCH_Z196_FEATURES 252 def_bool n 253 select HAVE_MARCH_Z10_FEATURES 254 255config HAVE_MARCH_ZEC12_FEATURES 256 def_bool n 257 select HAVE_MARCH_Z196_FEATURES 258 259config HAVE_MARCH_Z13_FEATURES 260 def_bool n 261 select HAVE_MARCH_ZEC12_FEATURES 262 263config HAVE_MARCH_Z14_FEATURES 264 def_bool n 265 select HAVE_MARCH_Z13_FEATURES 266 267config HAVE_MARCH_Z15_FEATURES 268 def_bool n 269 select HAVE_MARCH_Z14_FEATURES 270 271config HAVE_MARCH_Z16_FEATURES 272 def_bool n 273 select HAVE_MARCH_Z15_FEATURES 274 275choice 276 prompt "Processor type" 277 default MARCH_Z196 278 279config MARCH_Z10 280 bool "IBM System z10" 281 select HAVE_MARCH_Z10_FEATURES 282 depends on $(cc-option,-march=z10) 283 help 284 Select this to enable optimizations for IBM System z10 (2097 and 2098 285 series). This is the oldest machine generation currently supported. 286 287config MARCH_Z196 288 bool "IBM zEnterprise 114 and 196" 289 select HAVE_MARCH_Z196_FEATURES 290 depends on $(cc-option,-march=z196) 291 help 292 Select this to enable optimizations for IBM zEnterprise 114 and 196 293 (2818 and 2817 series). The kernel will be slightly faster but will 294 not work on older machines. 295 296config MARCH_ZEC12 297 bool "IBM zBC12 and zEC12" 298 select HAVE_MARCH_ZEC12_FEATURES 299 depends on $(cc-option,-march=zEC12) 300 help 301 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 302 2827 series). The kernel will be slightly faster but will not work on 303 older machines. 304 305config MARCH_Z13 306 bool "IBM z13s and z13" 307 select HAVE_MARCH_Z13_FEATURES 308 depends on $(cc-option,-march=z13) 309 help 310 Select this to enable optimizations for IBM z13s and z13 (2965 and 311 2964 series). The kernel will be slightly faster but will not work on 312 older machines. 313 314config MARCH_Z14 315 bool "IBM z14 ZR1 and z14" 316 select HAVE_MARCH_Z14_FEATURES 317 depends on $(cc-option,-march=z14) 318 help 319 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 320 and 3906 series). The kernel will be slightly faster but will not 321 work on older machines. 322 323config MARCH_Z15 324 bool "IBM z15" 325 select HAVE_MARCH_Z15_FEATURES 326 depends on $(cc-option,-march=z15) 327 help 328 Select this to enable optimizations for IBM z15 (8562 329 and 8561 series). The kernel will be slightly faster but will not 330 work on older machines. 331 332config MARCH_Z16 333 bool "IBM z16" 334 select HAVE_MARCH_Z16_FEATURES 335 depends on $(cc-option,-march=z16) 336 help 337 Select this to enable optimizations for IBM z16 (3931 and 338 3932 series). 339 340endchoice 341 342config MARCH_Z10_TUNE 343 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 344 345config MARCH_Z196_TUNE 346 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 347 348config MARCH_ZEC12_TUNE 349 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 350 351config MARCH_Z13_TUNE 352 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 353 354config MARCH_Z14_TUNE 355 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 356 357config MARCH_Z15_TUNE 358 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 359 360config MARCH_Z16_TUNE 361 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 362 363choice 364 prompt "Tune code generation" 365 default TUNE_DEFAULT 366 help 367 Cause the compiler to tune (-mtune) the generated code for a machine. 368 This will make the code run faster on the selected machine but 369 somewhat slower on other machines. 370 This option only changes how the compiler emits instructions, not the 371 selection of instructions itself, so the resulting kernel will run on 372 all other machines. 373 374config TUNE_DEFAULT 375 bool "Default" 376 help 377 Tune the generated code for the target processor for which the kernel 378 will be compiled. 379 380config TUNE_Z10 381 bool "IBM System z10" 382 383config TUNE_Z196 384 bool "IBM zEnterprise 114 and 196" 385 depends on $(cc-option,-mtune=z196) 386 387config TUNE_ZEC12 388 bool "IBM zBC12 and zEC12" 389 depends on $(cc-option,-mtune=zEC12) 390 391config TUNE_Z13 392 bool "IBM z13s and z13" 393 depends on $(cc-option,-mtune=z13) 394 395config TUNE_Z14 396 bool "IBM z14 ZR1 and z14" 397 depends on $(cc-option,-mtune=z14) 398 399config TUNE_Z15 400 bool "IBM z15" 401 depends on $(cc-option,-mtune=z15) 402 403config TUNE_Z16 404 bool "IBM z16" 405 depends on $(cc-option,-mtune=z16) 406 407endchoice 408 409config 64BIT 410 def_bool y 411 412config COMMAND_LINE_SIZE 413 int "Maximum size of kernel command line" 414 default 4096 415 range 896 1048576 416 help 417 This allows you to specify the maximum length of the kernel command 418 line. 419 420config COMPAT 421 def_bool y 422 prompt "Kernel support for 31 bit emulation" 423 select ARCH_WANT_OLD_COMPAT_IPC 424 select COMPAT_OLD_SIGACTION 425 select HAVE_UID16 426 depends on MULTIUSER 427 depends on !CC_IS_CLANG 428 help 429 Select this option if you want to enable your system kernel to 430 handle system-calls from ELF binaries for 31 bit ESA. This option 431 (and some other stuff like libraries and such) is needed for 432 executing 31 bit applications. It is safe to say "Y". 433 434config SMP 435 def_bool y 436 437config NR_CPUS 438 int "Maximum number of CPUs (2-512)" 439 range 2 512 440 default "64" 441 help 442 This allows you to specify the maximum number of CPUs which this 443 kernel will support. The maximum supported value is 512 and the 444 minimum value which makes sense is 2. 445 446 This is purely to save memory - each supported CPU adds 447 approximately sixteen kilobytes to the kernel image. 448 449config HOTPLUG_CPU 450 def_bool y 451 452config NUMA 453 bool "NUMA support" 454 depends on SCHED_TOPOLOGY 455 default n 456 help 457 Enable NUMA support 458 459 This option adds NUMA support to the kernel. 460 461config NODES_SHIFT 462 int 463 depends on NUMA 464 default "1" 465 466config SCHED_SMT 467 def_bool n 468 469config SCHED_MC 470 def_bool n 471 472config SCHED_BOOK 473 def_bool n 474 475config SCHED_DRAWER 476 def_bool n 477 478config SCHED_TOPOLOGY 479 def_bool y 480 prompt "Topology scheduler support" 481 select SCHED_SMT 482 select SCHED_MC 483 select SCHED_BOOK 484 select SCHED_DRAWER 485 help 486 Topology scheduler support improves the CPU scheduler's decision 487 making when dealing with machines that have multi-threading, 488 multiple cores or multiple books. 489 490source "kernel/Kconfig.hz" 491 492config KEXEC 493 def_bool y 494 select KEXEC_CORE 495 496config KEXEC_FILE 497 bool "kexec file based system call" 498 select KEXEC_CORE 499 depends on CRYPTO 500 depends on CRYPTO_SHA256 501 depends on CRYPTO_SHA256_S390 502 help 503 Enable the kexec file based system call. In contrast to the normal 504 kexec system call this system call takes file descriptors for the 505 kernel and initramfs as arguments. 506 507config ARCH_HAS_KEXEC_PURGATORY 508 def_bool y 509 depends on KEXEC_FILE 510 511config KEXEC_SIG 512 bool "Verify kernel signature during kexec_file_load() syscall" 513 depends on KEXEC_FILE && MODULE_SIG_FORMAT 514 help 515 This option makes kernel signature verification mandatory for 516 the kexec_file_load() syscall. 517 518 In addition to that option, you need to enable signature 519 verification for the corresponding kernel image type being 520 loaded in order for this to work. 521 522config KERNEL_NOBP 523 def_bool n 524 prompt "Enable modified branch prediction for the kernel by default" 525 help 526 If this option is selected the kernel will switch to a modified 527 branch prediction mode if the firmware interface is available. 528 The modified branch prediction mode improves the behaviour in 529 regard to speculative execution. 530 531 With the option enabled the kernel parameter "nobp=0" or "nospec" 532 can be used to run the kernel in the normal branch prediction mode. 533 534 With the option disabled the modified branch prediction mode is 535 enabled with the "nobp=1" kernel parameter. 536 537 If unsure, say N. 538 539config EXPOLINE 540 def_bool n 541 depends on $(cc-option,-mindirect-branch=thunk) 542 prompt "Avoid speculative indirect branches in the kernel" 543 help 544 Compile the kernel with the expoline compiler options to guard 545 against kernel-to-user data leaks by avoiding speculative indirect 546 branches. 547 Requires a compiler with -mindirect-branch=thunk support for full 548 protection. The kernel may run slower. 549 550 If unsure, say N. 551 552config EXPOLINE_EXTERN 553 def_bool n 554 depends on EXPOLINE 555 depends on CC_IS_GCC && GCC_VERSION >= 110200 556 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 557 prompt "Generate expolines as extern functions." 558 help 559 This option is required for some tooling like kpatch. The kernel is 560 compiled with -mindirect-branch=thunk-extern and requires a newer 561 compiler. 562 563 If unsure, say N. 564 565choice 566 prompt "Expoline default" 567 depends on EXPOLINE 568 default EXPOLINE_FULL 569 570config EXPOLINE_OFF 571 bool "spectre_v2=off" 572 573config EXPOLINE_AUTO 574 bool "spectre_v2=auto" 575 576config EXPOLINE_FULL 577 bool "spectre_v2=on" 578 579endchoice 580 581config RELOCATABLE 582 def_bool y 583 help 584 This builds a kernel image that retains relocation information 585 so it can be loaded at an arbitrary address. 586 The kernel is linked as a position-independent executable (PIE) 587 and contains dynamic relocations which are processed early in the 588 bootup process. 589 The relocations make the kernel image about 15% larger (compressed 590 10%), but are discarded at runtime. 591 Note: this option exists only for documentation purposes, please do 592 not remove it. 593 594config RANDOMIZE_BASE 595 bool "Randomize the address of the kernel image (KASLR)" 596 default y 597 help 598 In support of Kernel Address Space Layout Randomization (KASLR), 599 this randomizes the address at which the kernel image is loaded, 600 as a security feature that deters exploit attempts relying on 601 knowledge of the location of kernel internals. 602 603endmenu 604 605menu "Memory setup" 606 607config ARCH_SPARSEMEM_ENABLE 608 def_bool y 609 select SPARSEMEM_VMEMMAP_ENABLE 610 select SPARSEMEM_VMEMMAP 611 612config ARCH_SPARSEMEM_DEFAULT 613 def_bool y 614 615config MAX_PHYSMEM_BITS 616 int "Maximum size of supported physical memory in bits (42-53)" 617 range 42 53 618 default "46" 619 help 620 This option specifies the maximum supported size of physical memory 621 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 622 Increasing the number of bits also increases the kernel image size. 623 By default 46 bits (64TB) are supported. 624 625config CHECK_STACK 626 def_bool y 627 depends on !VMAP_STACK 628 prompt "Detect kernel stack overflow" 629 help 630 This option enables the compiler option -mstack-guard and 631 -mstack-size if they are available. If the compiler supports them 632 it will emit additional code to each function prolog to trigger 633 an illegal operation if the kernel stack is about to overflow. 634 635 Say N if you are unsure. 636 637config STACK_GUARD 638 int "Size of the guard area (128-1024)" 639 range 128 1024 640 depends on CHECK_STACK 641 default "256" 642 help 643 This allows you to specify the size of the guard area at the lower 644 end of the kernel stack. If the kernel stack points into the guard 645 area on function entry an illegal operation is triggered. The size 646 needs to be a power of 2. Please keep in mind that the size of an 647 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 648 The minimum size for the stack guard should be 256 for 31 bit and 649 512 for 64 bit. 650 651endmenu 652 653menu "I/O subsystem" 654 655config QDIO 656 def_tristate y 657 prompt "QDIO support" 658 help 659 This driver provides the Queued Direct I/O base support for 660 IBM System z. 661 662 To compile this driver as a module, choose M here: the 663 module will be called qdio. 664 665 If unsure, say Y. 666 667if PCI 668 669config PCI_NR_FUNCTIONS 670 int "Maximum number of PCI functions (1-4096)" 671 range 1 4096 672 default "512" 673 help 674 This allows you to specify the maximum number of PCI functions which 675 this kernel will support. 676 677endif # PCI 678 679config HAS_IOMEM 680 def_bool PCI 681 682config CHSC_SCH 683 def_tristate m 684 prompt "Support for CHSC subchannels" 685 help 686 This driver allows usage of CHSC subchannels. A CHSC subchannel 687 is usually present on LPAR only. 688 The driver creates a device /dev/chsc, which may be used to 689 obtain I/O configuration information about the machine and 690 to issue asynchronous chsc commands (DANGEROUS). 691 You will usually only want to use this interface on a special 692 LPAR designated for system management. 693 694 To compile this driver as a module, choose M here: the 695 module will be called chsc_sch. 696 697 If unsure, say N. 698 699config SCM_BUS 700 def_bool y 701 prompt "SCM bus driver" 702 help 703 Bus driver for Storage Class Memory. 704 705config EADM_SCH 706 def_tristate m 707 prompt "Support for EADM subchannels" 708 depends on SCM_BUS 709 help 710 This driver allows usage of EADM subchannels. EADM subchannels act 711 as a communication vehicle for SCM increments. 712 713 To compile this driver as a module, choose M here: the 714 module will be called eadm_sch. 715 716config VFIO_CCW 717 def_tristate n 718 prompt "Support for VFIO-CCW subchannels" 719 depends on S390_CCW_IOMMU 720 depends on VFIO 721 select VFIO_MDEV 722 help 723 This driver allows usage of I/O subchannels via VFIO-CCW. 724 725 To compile this driver as a module, choose M here: the 726 module will be called vfio_ccw. 727 728config VFIO_AP 729 def_tristate n 730 prompt "VFIO support for AP devices" 731 depends on S390_AP_IOMMU && KVM 732 depends on VFIO 733 depends on ZCRYPT 734 select VFIO_MDEV 735 help 736 This driver grants access to Adjunct Processor (AP) devices 737 via the VFIO mediated device interface. 738 739 To compile this driver as a module, choose M here: the module 740 will be called vfio_ap. 741 742endmenu 743 744menu "Dump support" 745 746config CRASH_DUMP 747 bool "kernel crash dumps" 748 select KEXEC 749 help 750 Generate crash dump after being started by kexec. 751 Crash dump kernels are loaded in the main kernel with kexec-tools 752 into a specially reserved region and then later executed after 753 a crash by kdump/kexec. 754 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 755 This option also enables s390 zfcpdump. 756 See also <file:Documentation/s390/zfcpdump.rst> 757 758endmenu 759 760config CCW 761 def_bool y 762 763config HAVE_PNETID 764 tristate 765 default (SMC || CCWGROUP) 766 767menu "Virtualization" 768 769config PROTECTED_VIRTUALIZATION_GUEST 770 def_bool n 771 prompt "Protected virtualization guest support" 772 help 773 Select this option, if you want to be able to run this 774 kernel as a protected virtualization KVM guest. 775 Protected virtualization capable machines have a mini hypervisor 776 located at machine level (an ultravisor). With help of the 777 Ultravisor, KVM will be able to run "protected" VMs, special 778 VMs whose memory and management data are unavailable to KVM. 779 780config PFAULT 781 def_bool y 782 prompt "Pseudo page fault support" 783 help 784 Select this option, if you want to use PFAULT pseudo page fault 785 handling under VM. If running native or in LPAR, this option 786 has no effect. If your VM does not support PFAULT, PAGEEX 787 pseudo page fault handling will be used. 788 Note that VM 4.2 supports PFAULT but has a bug in its 789 implementation that causes some problems. 790 Everybody who wants to run Linux under VM != VM4.2 should select 791 this option. 792 793config CMM 794 def_tristate n 795 prompt "Cooperative memory management" 796 help 797 Select this option, if you want to enable the kernel interface 798 to reduce the memory size of the system. This is accomplished 799 by allocating pages of memory and put them "on hold". This only 800 makes sense for a system running under VM where the unused pages 801 will be reused by VM for other guest systems. The interface 802 allows an external monitor to balance memory of many systems. 803 Everybody who wants to run Linux under VM should select this 804 option. 805 806config CMM_IUCV 807 def_bool y 808 prompt "IUCV special message interface to cooperative memory management" 809 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 810 help 811 Select this option to enable the special message interface to 812 the cooperative memory management. 813 814config APPLDATA_BASE 815 def_bool n 816 prompt "Linux - VM Monitor Stream, base infrastructure" 817 depends on PROC_SYSCTL 818 help 819 This provides a kernel interface for creating and updating z/VM APPLDATA 820 monitor records. The monitor records are updated at certain time 821 intervals, once the timer is started. 822 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 823 i.e. enables or disables monitoring on the Linux side. 824 A custom interval value (in seconds) can be written to 825 /proc/appldata/interval. 826 827 Defaults are 60 seconds interval and timer off. 828 The /proc entries can also be read from, showing the current settings. 829 830config APPLDATA_MEM 831 def_tristate m 832 prompt "Monitor memory management statistics" 833 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 834 help 835 This provides memory management related data to the Linux - VM Monitor 836 Stream, like paging/swapping rate, memory utilisation, etc. 837 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 838 APPLDATA monitor record, i.e. enables or disables monitoring this record 839 on the z/VM side. 840 841 Default is disabled. 842 The /proc entry can also be read from, showing the current settings. 843 844 This can also be compiled as a module, which will be called 845 appldata_mem.o. 846 847config APPLDATA_OS 848 def_tristate m 849 prompt "Monitor OS statistics" 850 depends on APPLDATA_BASE 851 help 852 This provides OS related data to the Linux - VM Monitor Stream, like 853 CPU utilisation, etc. 854 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 855 APPLDATA monitor record, i.e. enables or disables monitoring this record 856 on the z/VM side. 857 858 Default is disabled. 859 This can also be compiled as a module, which will be called 860 appldata_os.o. 861 862config APPLDATA_NET_SUM 863 def_tristate m 864 prompt "Monitor overall network statistics" 865 depends on APPLDATA_BASE && NET 866 help 867 This provides network related data to the Linux - VM Monitor Stream, 868 currently there is only a total sum of network I/O statistics, no 869 per-interface data. 870 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 871 APPLDATA monitor record, i.e. enables or disables monitoring this record 872 on the z/VM side. 873 874 Default is disabled. 875 This can also be compiled as a module, which will be called 876 appldata_net_sum.o. 877 878config S390_HYPFS_FS 879 def_bool y 880 prompt "s390 hypervisor file system support" 881 select SYS_HYPERVISOR 882 help 883 This is a virtual file system intended to provide accounting 884 information in an s390 hypervisor environment. 885 886source "arch/s390/kvm/Kconfig" 887 888config S390_GUEST 889 def_bool y 890 prompt "s390 support for virtio devices" 891 select TTY 892 select VIRTUALIZATION 893 select VIRTIO 894 help 895 Enabling this option adds support for virtio based paravirtual device 896 drivers on s390. 897 898 Select this option if you want to run the kernel as a guest under 899 the KVM hypervisor. 900 901endmenu 902 903config S390_MODULES_SANITY_TEST_HELPERS 904 def_bool n 905 906menu "Selftests" 907 908config S390_UNWIND_SELFTEST 909 def_tristate n 910 depends on KUNIT 911 default KUNIT_ALL_TESTS 912 prompt "Test unwind functions" 913 help 914 This option enables s390 specific stack unwinder testing kernel 915 module. This option is not useful for distributions or general 916 kernels, but only for kernel developers working on architecture code. 917 918 Say N if you are unsure. 919 920config S390_KPROBES_SANITY_TEST 921 def_tristate n 922 prompt "Enable s390 specific kprobes tests" 923 depends on KPROBES 924 depends on KUNIT 925 help 926 This option enables an s390 specific kprobes test module. This option 927 is not useful for distributions or general kernels, but only for kernel 928 developers working on architecture code. 929 930 Say N if you are unsure. 931 932config S390_MODULES_SANITY_TEST 933 def_tristate n 934 depends on KUNIT 935 default KUNIT_ALL_TESTS 936 prompt "Enable s390 specific modules tests" 937 select S390_MODULES_SANITY_TEST_HELPERS 938 help 939 This option enables an s390 specific modules test. This option is 940 not useful for distributions or general kernels, but only for 941 kernel developers working on architecture code. 942 943 Say N if you are unsure. 944endmenu 945