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_CSUM 30 bool 31 default y if KASAN 32 33config GENERIC_LOCKBREAK 34 def_bool y if PREEMPTION 35 36config PGSTE 37 def_bool y if KVM 38 39config AUDIT_ARCH 40 def_bool y 41 42config NO_IOPORT_MAP 43 def_bool y 44 45config PCI_QUIRKS 46 def_bool n 47 48config ARCH_SUPPORTS_UPROBES 49 def_bool y 50 51config KASAN_SHADOW_OFFSET 52 hex 53 depends on KASAN 54 default 0x1C000000000000 55 56config S390 57 def_bool y 58 # 59 # Note: keep this list sorted alphabetically 60 # 61 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 62 select ALTERNATE_USER_ADDRESS_SPACE 63 select ARCH_32BIT_USTAT_F_TINODE 64 select ARCH_BINFMT_ELF_STATE 65 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 66 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 67 select ARCH_ENABLE_MEMORY_HOTREMOVE 68 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 69 select ARCH_HAS_CURRENT_STACK_POINTER 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_MEM_ENCRYPT 80 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 81 select ARCH_HAS_PTE_SPECIAL 82 select ARCH_HAS_SCALED_CPUTIME 83 select ARCH_HAS_SET_MEMORY 84 select ARCH_HAS_STRICT_KERNEL_RWX 85 select ARCH_HAS_STRICT_MODULE_RWX 86 select ARCH_HAS_SYSCALL_WRAPPER 87 select ARCH_HAS_UBSAN_SANITIZE_ALL 88 select ARCH_HAS_VDSO_DATA 89 select ARCH_HAVE_NMI_SAFE_CMPXCHG 90 select ARCH_INLINE_READ_LOCK 91 select ARCH_INLINE_READ_LOCK_BH 92 select ARCH_INLINE_READ_LOCK_IRQ 93 select ARCH_INLINE_READ_LOCK_IRQSAVE 94 select ARCH_INLINE_READ_TRYLOCK 95 select ARCH_INLINE_READ_UNLOCK 96 select ARCH_INLINE_READ_UNLOCK_BH 97 select ARCH_INLINE_READ_UNLOCK_IRQ 98 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 99 select ARCH_INLINE_SPIN_LOCK 100 select ARCH_INLINE_SPIN_LOCK_BH 101 select ARCH_INLINE_SPIN_LOCK_IRQ 102 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 103 select ARCH_INLINE_SPIN_TRYLOCK 104 select ARCH_INLINE_SPIN_TRYLOCK_BH 105 select ARCH_INLINE_SPIN_UNLOCK 106 select ARCH_INLINE_SPIN_UNLOCK_BH 107 select ARCH_INLINE_SPIN_UNLOCK_IRQ 108 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 109 select ARCH_INLINE_WRITE_LOCK 110 select ARCH_INLINE_WRITE_LOCK_BH 111 select ARCH_INLINE_WRITE_LOCK_IRQ 112 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 113 select ARCH_INLINE_WRITE_TRYLOCK 114 select ARCH_INLINE_WRITE_UNLOCK 115 select ARCH_INLINE_WRITE_UNLOCK_BH 116 select ARCH_INLINE_WRITE_UNLOCK_IRQ 117 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 118 select ARCH_STACKWALK 119 select ARCH_SUPPORTS_ATOMIC_RMW 120 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 121 select ARCH_SUPPORTS_HUGETLBFS 122 select ARCH_SUPPORTS_NUMA_BALANCING 123 select ARCH_USE_BUILTIN_BSWAP 124 select ARCH_USE_CMPXCHG_LOCKREF 125 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 126 select ARCH_WANTS_NO_INSTR 127 select ARCH_WANT_DEFAULT_BPF_JIT 128 select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP 129 select ARCH_WANT_IPC_PARSE_VERSION 130 select BUILDTIME_TABLE_SORT 131 select CLONE_BACKWARDS2 132 select DMA_OPS if PCI 133 select DYNAMIC_FTRACE if FUNCTION_TRACER 134 select GCC12_NO_ARRAY_BOUNDS 135 select GENERIC_ALLOCATOR 136 select GENERIC_CPU_AUTOPROBE 137 select GENERIC_CPU_VULNERABILITIES 138 select GENERIC_ENTRY 139 select GENERIC_GETTIMEOFDAY 140 select GENERIC_PTDUMP 141 select GENERIC_SMP_IDLE_THREAD 142 select GENERIC_TIME_VSYSCALL 143 select GENERIC_VDSO_TIME_NS 144 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 145 select HAVE_ARCH_AUDITSYSCALL 146 select HAVE_ARCH_JUMP_LABEL 147 select HAVE_ARCH_JUMP_LABEL_RELATIVE 148 select HAVE_ARCH_KASAN 149 select HAVE_ARCH_KASAN_VMALLOC 150 select HAVE_ARCH_KCSAN 151 select HAVE_ARCH_KFENCE 152 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 153 select HAVE_ARCH_SECCOMP_FILTER 154 select HAVE_ARCH_SOFT_DIRTY 155 select HAVE_ARCH_TRACEHOOK 156 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 157 select HAVE_ARCH_VMAP_STACK 158 select HAVE_ASM_MODVERSIONS 159 select HAVE_CMPXCHG_DOUBLE 160 select HAVE_CMPXCHG_LOCAL 161 select HAVE_DEBUG_KMEMLEAK 162 select HAVE_DMA_CONTIGUOUS 163 select HAVE_DYNAMIC_FTRACE 164 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 165 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 166 select HAVE_DYNAMIC_FTRACE_WITH_REGS 167 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 168 select HAVE_EFFICIENT_UNALIGNED_ACCESS 169 select HAVE_FAST_GUP 170 select HAVE_FENTRY 171 select HAVE_FTRACE_MCOUNT_RECORD 172 select HAVE_FUNCTION_ARG_ACCESS_API 173 select HAVE_FUNCTION_ERROR_INJECTION 174 select HAVE_FUNCTION_GRAPH_TRACER 175 select HAVE_FUNCTION_TRACER 176 select HAVE_GCC_PLUGINS 177 select HAVE_GENERIC_VDSO 178 select HAVE_IOREMAP_PROT if PCI 179 select HAVE_KERNEL_BZIP2 180 select HAVE_KERNEL_GZIP 181 select HAVE_KERNEL_LZ4 182 select HAVE_KERNEL_LZMA 183 select HAVE_KERNEL_LZO 184 select HAVE_KERNEL_UNCOMPRESSED 185 select HAVE_KERNEL_XZ 186 select HAVE_KERNEL_ZSTD 187 select HAVE_KPROBES 188 select HAVE_KPROBES_ON_FTRACE 189 select HAVE_KRETPROBES 190 select HAVE_KVM 191 select HAVE_LIVEPATCH 192 select HAVE_MEMBLOCK_PHYS_MAP 193 select HAVE_MOD_ARCH_SPECIFIC 194 select HAVE_NMI 195 select HAVE_NOP_MCOUNT 196 select HAVE_PCI 197 select HAVE_PERF_EVENTS 198 select HAVE_PERF_REGS 199 select HAVE_PERF_USER_STACK_DUMP 200 select HAVE_REGS_AND_STACK_ACCESS_API 201 select HAVE_RELIABLE_STACKTRACE 202 select HAVE_RETHOOK 203 select HAVE_RSEQ 204 select HAVE_SAMPLE_FTRACE_DIRECT 205 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 206 select HAVE_SETUP_PER_CPU_AREA 207 select HAVE_SOFTIRQ_ON_OWN_STACK 208 select HAVE_SYSCALL_TRACEPOINTS 209 select HAVE_VIRT_CPU_ACCOUNTING 210 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 211 select IOMMU_HELPER if PCI 212 select IOMMU_SUPPORT if PCI 213 select MMU_GATHER_MERGE_VMAS 214 select MMU_GATHER_NO_GATHER 215 select MMU_GATHER_RCU_TABLE_FREE 216 select MODULES_USE_ELF_RELA 217 select NEED_DMA_MAP_STATE if PCI 218 select NEED_PER_CPU_EMBED_FIRST_CHUNK 219 select NEED_SG_DMA_LENGTH if PCI 220 select OLD_SIGACTION 221 select OLD_SIGSUSPEND3 222 select PCI_DOMAINS if PCI 223 select PCI_MSI if PCI 224 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 225 select SPARSE_IRQ 226 select SWIOTLB 227 select SYSCTL_EXCEPTION_TRACE 228 select THREAD_INFO_IN_TASK 229 select TRACE_IRQFLAGS_SUPPORT 230 select TTY 231 select VIRT_CPU_ACCOUNTING 232 select ZONE_DMA 233 # Note: keep the above list sorted alphabetically 234 235config SCHED_OMIT_FRAME_POINTER 236 def_bool y 237 238config PGTABLE_LEVELS 239 int 240 default 5 241 242source "kernel/livepatch/Kconfig" 243 244menu "Processor type and features" 245 246config HAVE_MARCH_Z10_FEATURES 247 def_bool n 248 249config HAVE_MARCH_Z196_FEATURES 250 def_bool n 251 select HAVE_MARCH_Z10_FEATURES 252 253config HAVE_MARCH_ZEC12_FEATURES 254 def_bool n 255 select HAVE_MARCH_Z196_FEATURES 256 257config HAVE_MARCH_Z13_FEATURES 258 def_bool n 259 select HAVE_MARCH_ZEC12_FEATURES 260 261config HAVE_MARCH_Z14_FEATURES 262 def_bool n 263 select HAVE_MARCH_Z13_FEATURES 264 265config HAVE_MARCH_Z15_FEATURES 266 def_bool n 267 select HAVE_MARCH_Z14_FEATURES 268 269config HAVE_MARCH_Z16_FEATURES 270 def_bool n 271 select HAVE_MARCH_Z15_FEATURES 272 273choice 274 prompt "Processor type" 275 default MARCH_Z196 276 277config MARCH_Z10 278 bool "IBM System z10" 279 select HAVE_MARCH_Z10_FEATURES 280 depends on $(cc-option,-march=z10) 281 help 282 Select this to enable optimizations for IBM System z10 (2097 and 2098 283 series). This is the oldest machine generation currently supported. 284 285config MARCH_Z196 286 bool "IBM zEnterprise 114 and 196" 287 select HAVE_MARCH_Z196_FEATURES 288 depends on $(cc-option,-march=z196) 289 help 290 Select this to enable optimizations for IBM zEnterprise 114 and 196 291 (2818 and 2817 series). The kernel will be slightly faster but will 292 not work on older machines. 293 294config MARCH_ZEC12 295 bool "IBM zBC12 and zEC12" 296 select HAVE_MARCH_ZEC12_FEATURES 297 depends on $(cc-option,-march=zEC12) 298 help 299 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 300 2827 series). The kernel will be slightly faster but will not work on 301 older machines. 302 303config MARCH_Z13 304 bool "IBM z13s and z13" 305 select HAVE_MARCH_Z13_FEATURES 306 depends on $(cc-option,-march=z13) 307 help 308 Select this to enable optimizations for IBM z13s and z13 (2965 and 309 2964 series). The kernel will be slightly faster but will not work on 310 older machines. 311 312config MARCH_Z14 313 bool "IBM z14 ZR1 and z14" 314 select HAVE_MARCH_Z14_FEATURES 315 depends on $(cc-option,-march=z14) 316 help 317 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 318 and 3906 series). The kernel will be slightly faster but will not 319 work on older machines. 320 321config MARCH_Z15 322 bool "IBM z15" 323 select HAVE_MARCH_Z15_FEATURES 324 depends on $(cc-option,-march=z15) 325 help 326 Select this to enable optimizations for IBM z15 (8562 327 and 8561 series). The kernel will be slightly faster but will not 328 work on older machines. 329 330config MARCH_Z16 331 bool "IBM z16" 332 select HAVE_MARCH_Z16_FEATURES 333 depends on $(cc-option,-march=z16) 334 help 335 Select this to enable optimizations for IBM z16 (3931 and 336 3932 series). 337 338endchoice 339 340config MARCH_Z10_TUNE 341 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 342 343config MARCH_Z196_TUNE 344 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 345 346config MARCH_ZEC12_TUNE 347 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 348 349config MARCH_Z13_TUNE 350 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 351 352config MARCH_Z14_TUNE 353 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 354 355config MARCH_Z15_TUNE 356 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 357 358config MARCH_Z16_TUNE 359 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 360 361choice 362 prompt "Tune code generation" 363 default TUNE_DEFAULT 364 help 365 Cause the compiler to tune (-mtune) the generated code for a machine. 366 This will make the code run faster on the selected machine but 367 somewhat slower on other machines. 368 This option only changes how the compiler emits instructions, not the 369 selection of instructions itself, so the resulting kernel will run on 370 all other machines. 371 372config TUNE_DEFAULT 373 bool "Default" 374 help 375 Tune the generated code for the target processor for which the kernel 376 will be compiled. 377 378config TUNE_Z10 379 bool "IBM System z10" 380 381config TUNE_Z196 382 bool "IBM zEnterprise 114 and 196" 383 depends on $(cc-option,-mtune=z196) 384 385config TUNE_ZEC12 386 bool "IBM zBC12 and zEC12" 387 depends on $(cc-option,-mtune=zEC12) 388 389config TUNE_Z13 390 bool "IBM z13s and z13" 391 depends on $(cc-option,-mtune=z13) 392 393config TUNE_Z14 394 bool "IBM z14 ZR1 and z14" 395 depends on $(cc-option,-mtune=z14) 396 397config TUNE_Z15 398 bool "IBM z15" 399 depends on $(cc-option,-mtune=z15) 400 401config TUNE_Z16 402 bool "IBM z16" 403 depends on $(cc-option,-mtune=z16) 404 405endchoice 406 407config 64BIT 408 def_bool y 409 410config COMMAND_LINE_SIZE 411 int "Maximum size of kernel command line" 412 default 4096 413 range 896 1048576 414 help 415 This allows you to specify the maximum length of the kernel command 416 line. 417 418config COMPAT 419 def_bool y 420 prompt "Kernel support for 31 bit emulation" 421 select ARCH_WANT_OLD_COMPAT_IPC 422 select COMPAT_OLD_SIGACTION 423 select HAVE_UID16 424 depends on MULTIUSER 425 depends on !CC_IS_CLANG 426 help 427 Select this option if you want to enable your system kernel to 428 handle system-calls from ELF binaries for 31 bit ESA. This option 429 (and some other stuff like libraries and such) is needed for 430 executing 31 bit applications. It is safe to say "Y". 431 432config SMP 433 def_bool y 434 435config NR_CPUS 436 int "Maximum number of CPUs (2-512)" 437 range 2 512 438 default "64" 439 help 440 This allows you to specify the maximum number of CPUs which this 441 kernel will support. The maximum supported value is 512 and the 442 minimum value which makes sense is 2. 443 444 This is purely to save memory - each supported CPU adds 445 approximately sixteen kilobytes to the kernel image. 446 447config HOTPLUG_CPU 448 def_bool y 449 450config NUMA 451 bool "NUMA support" 452 depends on SCHED_TOPOLOGY 453 default n 454 help 455 Enable NUMA support 456 457 This option adds NUMA support to the kernel. 458 459config NODES_SHIFT 460 int 461 depends on NUMA 462 default "1" 463 464config SCHED_SMT 465 def_bool n 466 467config SCHED_MC 468 def_bool n 469 470config SCHED_BOOK 471 def_bool n 472 473config SCHED_DRAWER 474 def_bool n 475 476config SCHED_TOPOLOGY 477 def_bool y 478 prompt "Topology scheduler support" 479 select SCHED_SMT 480 select SCHED_MC 481 select SCHED_BOOK 482 select SCHED_DRAWER 483 help 484 Topology scheduler support improves the CPU scheduler's decision 485 making when dealing with machines that have multi-threading, 486 multiple cores or multiple books. 487 488source "kernel/Kconfig.hz" 489 490config KEXEC 491 def_bool y 492 select KEXEC_CORE 493 494config KEXEC_FILE 495 bool "kexec file based system call" 496 select KEXEC_CORE 497 depends on CRYPTO 498 depends on CRYPTO_SHA256 499 depends on CRYPTO_SHA256_S390 500 help 501 Enable the kexec file based system call. In contrast to the normal 502 kexec system call this system call takes file descriptors for the 503 kernel and initramfs as arguments. 504 505config ARCH_HAS_KEXEC_PURGATORY 506 def_bool y 507 depends on KEXEC_FILE 508 509config KEXEC_SIG 510 bool "Verify kernel signature during kexec_file_load() syscall" 511 depends on KEXEC_FILE && MODULE_SIG_FORMAT 512 help 513 This option makes kernel signature verification mandatory for 514 the kexec_file_load() syscall. 515 516 In addition to that option, you need to enable signature 517 verification for the corresponding kernel image type being 518 loaded in order for this to work. 519 520config KERNEL_NOBP 521 def_bool n 522 prompt "Enable modified branch prediction for the kernel by default" 523 help 524 If this option is selected the kernel will switch to a modified 525 branch prediction mode if the firmware interface is available. 526 The modified branch prediction mode improves the behaviour in 527 regard to speculative execution. 528 529 With the option enabled the kernel parameter "nobp=0" or "nospec" 530 can be used to run the kernel in the normal branch prediction mode. 531 532 With the option disabled the modified branch prediction mode is 533 enabled with the "nobp=1" kernel parameter. 534 535 If unsure, say N. 536 537config EXPOLINE 538 def_bool n 539 depends on $(cc-option,-mindirect-branch=thunk) 540 prompt "Avoid speculative indirect branches in the kernel" 541 help 542 Compile the kernel with the expoline compiler options to guard 543 against kernel-to-user data leaks by avoiding speculative indirect 544 branches. 545 Requires a compiler with -mindirect-branch=thunk support for full 546 protection. The kernel may run slower. 547 548 If unsure, say N. 549 550config EXPOLINE_EXTERN 551 def_bool n 552 depends on EXPOLINE 553 depends on CC_IS_GCC && GCC_VERSION >= 110200 554 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 555 prompt "Generate expolines as extern functions." 556 help 557 This option is required for some tooling like kpatch. The kernel is 558 compiled with -mindirect-branch=thunk-extern and requires a newer 559 compiler. 560 561 If unsure, say N. 562 563choice 564 prompt "Expoline default" 565 depends on EXPOLINE 566 default EXPOLINE_FULL 567 568config EXPOLINE_OFF 569 bool "spectre_v2=off" 570 571config EXPOLINE_AUTO 572 bool "spectre_v2=auto" 573 574config EXPOLINE_FULL 575 bool "spectre_v2=on" 576 577endchoice 578 579config RELOCATABLE 580 def_bool y 581 help 582 This builds a kernel image that retains relocation information 583 so it can be loaded at an arbitrary address. 584 The kernel is linked as a position-independent executable (PIE) 585 and contains dynamic relocations which are processed early in the 586 bootup process. 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 RANDOMIZE_BASE 593 bool "Randomize the address of the kernel image (KASLR)" 594 default y 595 help 596 In support of Kernel Address Space Layout Randomization (KASLR), 597 this randomizes the address at which the kernel image is loaded, 598 as a security feature that deters exploit attempts relying on 599 knowledge of the location of kernel internals. 600 601endmenu 602 603menu "Memory setup" 604 605config ARCH_SPARSEMEM_ENABLE 606 def_bool y 607 select SPARSEMEM_VMEMMAP_ENABLE 608 select SPARSEMEM_VMEMMAP 609 610config ARCH_SPARSEMEM_DEFAULT 611 def_bool y 612 613config MAX_PHYSMEM_BITS 614 int "Maximum size of supported physical memory in bits (42-53)" 615 range 42 53 616 default "46" 617 help 618 This option specifies the maximum supported size of physical memory 619 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 620 Increasing the number of bits also increases the kernel image size. 621 By default 46 bits (64TB) are supported. 622 623config CHECK_STACK 624 def_bool y 625 depends on !VMAP_STACK 626 prompt "Detect kernel stack overflow" 627 help 628 This option enables the compiler option -mstack-guard and 629 -mstack-size if they are available. If the compiler supports them 630 it will emit additional code to each function prolog to trigger 631 an illegal operation if the kernel stack is about to overflow. 632 633 Say N if you are unsure. 634 635config STACK_GUARD 636 int "Size of the guard area (128-1024)" 637 range 128 1024 638 depends on CHECK_STACK 639 default "256" 640 help 641 This allows you to specify the size of the guard area at the lower 642 end of the kernel stack. If the kernel stack points into the guard 643 area on function entry an illegal operation is triggered. The size 644 needs to be a power of 2. Please keep in mind that the size of an 645 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 646 The minimum size for the stack guard should be 256 for 31 bit and 647 512 for 64 bit. 648 649endmenu 650 651menu "I/O subsystem" 652 653config QDIO 654 def_tristate y 655 prompt "QDIO support" 656 help 657 This driver provides the Queued Direct I/O base support for 658 IBM System z. 659 660 To compile this driver as a module, choose M here: the 661 module will be called qdio. 662 663 If unsure, say Y. 664 665if PCI 666 667config PCI_NR_FUNCTIONS 668 int "Maximum number of PCI functions (1-4096)" 669 range 1 4096 670 default "512" 671 help 672 This allows you to specify the maximum number of PCI functions which 673 this kernel will support. 674 675endif # PCI 676 677config HAS_IOMEM 678 def_bool PCI 679 680config CHSC_SCH 681 def_tristate m 682 prompt "Support for CHSC subchannels" 683 help 684 This driver allows usage of CHSC subchannels. A CHSC subchannel 685 is usually present on LPAR only. 686 The driver creates a device /dev/chsc, which may be used to 687 obtain I/O configuration information about the machine and 688 to issue asynchronous chsc commands (DANGEROUS). 689 You will usually only want to use this interface on a special 690 LPAR designated for system management. 691 692 To compile this driver as a module, choose M here: the 693 module will be called chsc_sch. 694 695 If unsure, say N. 696 697config SCM_BUS 698 def_bool y 699 prompt "SCM bus driver" 700 help 701 Bus driver for Storage Class Memory. 702 703config EADM_SCH 704 def_tristate m 705 prompt "Support for EADM subchannels" 706 depends on SCM_BUS 707 help 708 This driver allows usage of EADM subchannels. EADM subchannels act 709 as a communication vehicle for SCM increments. 710 711 To compile this driver as a module, choose M here: the 712 module will be called eadm_sch. 713 714config VFIO_CCW 715 def_tristate n 716 prompt "Support for VFIO-CCW subchannels" 717 depends on S390_CCW_IOMMU 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 S390_AP_IOMMU && 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 742menu "Dump support" 743 744config CRASH_DUMP 745 bool "kernel crash dumps" 746 select KEXEC 747 help 748 Generate crash dump after being started by kexec. 749 Crash dump kernels are loaded in the main kernel with kexec-tools 750 into a specially reserved region and then later executed after 751 a crash by kdump/kexec. 752 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 753 This option also enables s390 zfcpdump. 754 See also <file:Documentation/s390/zfcpdump.rst> 755 756endmenu 757 758config CCW 759 def_bool y 760 761config HAVE_PNETID 762 tristate 763 default (SMC || CCWGROUP) 764 765menu "Virtualization" 766 767config PROTECTED_VIRTUALIZATION_GUEST 768 def_bool n 769 prompt "Protected virtualization guest support" 770 help 771 Select this option, if you want to be able to run this 772 kernel as a protected virtualization KVM guest. 773 Protected virtualization capable machines have a mini hypervisor 774 located at machine level (an ultravisor). With help of the 775 Ultravisor, KVM will be able to run "protected" VMs, special 776 VMs whose memory and management data are unavailable to KVM. 777 778config PFAULT 779 def_bool y 780 prompt "Pseudo page fault support" 781 help 782 Select this option, if you want to use PFAULT pseudo page fault 783 handling under VM. If running native or in LPAR, this option 784 has no effect. If your VM does not support PFAULT, PAGEEX 785 pseudo page fault handling will be used. 786 Note that VM 4.2 supports PFAULT but has a bug in its 787 implementation that causes some problems. 788 Everybody who wants to run Linux under VM != VM4.2 should select 789 this option. 790 791config CMM 792 def_tristate n 793 prompt "Cooperative memory management" 794 help 795 Select this option, if you want to enable the kernel interface 796 to reduce the memory size of the system. This is accomplished 797 by allocating pages of memory and put them "on hold". This only 798 makes sense for a system running under VM where the unused pages 799 will be reused by VM for other guest systems. The interface 800 allows an external monitor to balance memory of many systems. 801 Everybody who wants to run Linux under VM should select this 802 option. 803 804config CMM_IUCV 805 def_bool y 806 prompt "IUCV special message interface to cooperative memory management" 807 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 808 help 809 Select this option to enable the special message interface to 810 the cooperative memory management. 811 812config APPLDATA_BASE 813 def_bool n 814 prompt "Linux - VM Monitor Stream, base infrastructure" 815 depends on PROC_SYSCTL 816 help 817 This provides a kernel interface for creating and updating z/VM APPLDATA 818 monitor records. The monitor records are updated at certain time 819 intervals, once the timer is started. 820 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 821 i.e. enables or disables monitoring on the Linux side. 822 A custom interval value (in seconds) can be written to 823 /proc/appldata/interval. 824 825 Defaults are 60 seconds interval and timer off. 826 The /proc entries can also be read from, showing the current settings. 827 828config APPLDATA_MEM 829 def_tristate m 830 prompt "Monitor memory management statistics" 831 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 832 help 833 This provides memory management related data to the Linux - VM Monitor 834 Stream, like paging/swapping rate, memory utilisation, etc. 835 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 836 APPLDATA monitor record, i.e. enables or disables monitoring this record 837 on the z/VM side. 838 839 Default is disabled. 840 The /proc entry can also be read from, showing the current settings. 841 842 This can also be compiled as a module, which will be called 843 appldata_mem.o. 844 845config APPLDATA_OS 846 def_tristate m 847 prompt "Monitor OS statistics" 848 depends on APPLDATA_BASE 849 help 850 This provides OS related data to the Linux - VM Monitor Stream, like 851 CPU utilisation, etc. 852 Writing 1 or 0 to /proc/appldata/os 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_os.o. 859 860config APPLDATA_NET_SUM 861 def_tristate m 862 prompt "Monitor overall network statistics" 863 depends on APPLDATA_BASE && NET 864 help 865 This provides network related data to the Linux - VM Monitor Stream, 866 currently there is only a total sum of network I/O statistics, no 867 per-interface data. 868 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 869 APPLDATA monitor record, i.e. enables or disables monitoring this record 870 on the z/VM side. 871 872 Default is disabled. 873 This can also be compiled as a module, which will be called 874 appldata_net_sum.o. 875 876config S390_HYPFS_FS 877 def_bool y 878 prompt "s390 hypervisor file system support" 879 select SYS_HYPERVISOR 880 help 881 This is a virtual file system intended to provide accounting 882 information in an s390 hypervisor environment. 883 884source "arch/s390/kvm/Kconfig" 885 886config S390_GUEST 887 def_bool y 888 prompt "s390 support for virtio devices" 889 select TTY 890 select VIRTUALIZATION 891 select VIRTIO 892 help 893 Enabling this option adds support for virtio based paravirtual device 894 drivers on s390. 895 896 Select this option if you want to run the kernel as a guest under 897 the KVM hypervisor. 898 899endmenu 900 901config S390_MODULES_SANITY_TEST_HELPERS 902 def_bool n 903 904menu "Selftests" 905 906config S390_UNWIND_SELFTEST 907 def_tristate n 908 depends on KUNIT 909 default KUNIT_ALL_TESTS 910 prompt "Test unwind functions" 911 help 912 This option enables s390 specific stack unwinder testing kernel 913 module. This option is not useful for distributions or general 914 kernels, but only for kernel developers working on architecture code. 915 916 Say N if you are unsure. 917 918config S390_KPROBES_SANITY_TEST 919 def_tristate n 920 prompt "Enable s390 specific kprobes tests" 921 depends on KPROBES 922 depends on KUNIT 923 help 924 This option enables an s390 specific kprobes test module. This option 925 is not useful for distributions or general kernels, but only for kernel 926 developers working on architecture code. 927 928 Say N if you are unsure. 929 930config S390_MODULES_SANITY_TEST 931 def_tristate n 932 depends on KUNIT 933 default KUNIT_ALL_TESTS 934 prompt "Enable s390 specific modules tests" 935 select S390_MODULES_SANITY_TEST_HELPERS 936 help 937 This option enables an s390 specific modules test. This option is 938 not useful for distributions or general kernels, but only for 939 kernel developers working on architecture code. 940 941 Say N if you are unsure. 942endmenu 943