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_MEM_ENCRYPT 76 select ARCH_HAS_PTE_SPECIAL 77 select ARCH_HAS_SCALED_CPUTIME 78 select ARCH_HAS_SET_MEMORY 79 select ARCH_HAS_STRICT_KERNEL_RWX 80 select ARCH_HAS_STRICT_MODULE_RWX 81 select ARCH_HAS_SYSCALL_WRAPPER 82 select ARCH_HAS_UBSAN_SANITIZE_ALL 83 select ARCH_HAS_VDSO_DATA 84 select ARCH_HAVE_NMI_SAFE_CMPXCHG 85 select ARCH_INLINE_READ_LOCK 86 select ARCH_INLINE_READ_LOCK_BH 87 select ARCH_INLINE_READ_LOCK_IRQ 88 select ARCH_INLINE_READ_LOCK_IRQSAVE 89 select ARCH_INLINE_READ_TRYLOCK 90 select ARCH_INLINE_READ_UNLOCK 91 select ARCH_INLINE_READ_UNLOCK_BH 92 select ARCH_INLINE_READ_UNLOCK_IRQ 93 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 94 select ARCH_INLINE_SPIN_LOCK 95 select ARCH_INLINE_SPIN_LOCK_BH 96 select ARCH_INLINE_SPIN_LOCK_IRQ 97 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 98 select ARCH_INLINE_SPIN_TRYLOCK 99 select ARCH_INLINE_SPIN_TRYLOCK_BH 100 select ARCH_INLINE_SPIN_UNLOCK 101 select ARCH_INLINE_SPIN_UNLOCK_BH 102 select ARCH_INLINE_SPIN_UNLOCK_IRQ 103 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 104 select ARCH_INLINE_WRITE_LOCK 105 select ARCH_INLINE_WRITE_LOCK_BH 106 select ARCH_INLINE_WRITE_LOCK_IRQ 107 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 108 select ARCH_INLINE_WRITE_TRYLOCK 109 select ARCH_INLINE_WRITE_UNLOCK 110 select ARCH_INLINE_WRITE_UNLOCK_BH 111 select ARCH_INLINE_WRITE_UNLOCK_IRQ 112 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 113 select ARCH_STACKWALK 114 select ARCH_SUPPORTS_ATOMIC_RMW 115 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 116 select ARCH_SUPPORTS_HUGETLBFS 117 select ARCH_SUPPORTS_NUMA_BALANCING 118 select ARCH_USE_BUILTIN_BSWAP 119 select ARCH_USE_CMPXCHG_LOCKREF 120 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 121 select ARCH_WANTS_NO_INSTR 122 select ARCH_WANT_DEFAULT_BPF_JIT 123 select ARCH_WANT_IPC_PARSE_VERSION 124 select BUILDTIME_TABLE_SORT 125 select CLONE_BACKWARDS2 126 select DMA_OPS if PCI 127 select DYNAMIC_FTRACE if FUNCTION_TRACER 128 select GCC12_NO_ARRAY_BOUNDS 129 select GENERIC_ALLOCATOR 130 select GENERIC_CPU_AUTOPROBE 131 select GENERIC_CPU_VULNERABILITIES 132 select GENERIC_ENTRY 133 select GENERIC_GETTIMEOFDAY 134 select GENERIC_PTDUMP 135 select GENERIC_SMP_IDLE_THREAD 136 select GENERIC_TIME_VSYSCALL 137 select GENERIC_VDSO_TIME_NS 138 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 139 select HAVE_ARCH_AUDITSYSCALL 140 select HAVE_ARCH_JUMP_LABEL 141 select HAVE_ARCH_JUMP_LABEL_RELATIVE 142 select HAVE_ARCH_KASAN 143 select HAVE_ARCH_KASAN_VMALLOC 144 select HAVE_ARCH_KCSAN 145 select HAVE_ARCH_KFENCE 146 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 147 select HAVE_ARCH_SECCOMP_FILTER 148 select HAVE_ARCH_SOFT_DIRTY 149 select HAVE_ARCH_TRACEHOOK 150 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 151 select HAVE_ARCH_VMAP_STACK 152 select HAVE_ASM_MODVERSIONS 153 select HAVE_CMPXCHG_DOUBLE 154 select HAVE_CMPXCHG_LOCAL 155 select HAVE_DEBUG_KMEMLEAK 156 select HAVE_DMA_CONTIGUOUS 157 select HAVE_DYNAMIC_FTRACE 158 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 159 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 160 select HAVE_DYNAMIC_FTRACE_WITH_REGS 161 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 162 select HAVE_EFFICIENT_UNALIGNED_ACCESS 163 select HAVE_FAST_GUP 164 select HAVE_FENTRY 165 select HAVE_FTRACE_MCOUNT_RECORD 166 select HAVE_FUNCTION_ARG_ACCESS_API 167 select HAVE_FUNCTION_ERROR_INJECTION 168 select HAVE_FUNCTION_GRAPH_TRACER 169 select HAVE_FUNCTION_TRACER 170 select HAVE_GCC_PLUGINS 171 select HAVE_GENERIC_VDSO 172 select HAVE_IOREMAP_PROT if PCI 173 select HAVE_KERNEL_BZIP2 174 select HAVE_KERNEL_GZIP 175 select HAVE_KERNEL_LZ4 176 select HAVE_KERNEL_LZMA 177 select HAVE_KERNEL_LZO 178 select HAVE_KERNEL_UNCOMPRESSED 179 select HAVE_KERNEL_XZ 180 select HAVE_KERNEL_ZSTD 181 select HAVE_KPROBES 182 select HAVE_KPROBES_ON_FTRACE 183 select HAVE_KRETPROBES 184 select HAVE_KVM 185 select HAVE_LIVEPATCH 186 select HAVE_MEMBLOCK_PHYS_MAP 187 select HAVE_MOD_ARCH_SPECIFIC 188 select HAVE_NMI 189 select HAVE_NOP_MCOUNT 190 select HAVE_PCI 191 select HAVE_PERF_EVENTS 192 select HAVE_PERF_REGS 193 select HAVE_PERF_USER_STACK_DUMP 194 select HAVE_REGS_AND_STACK_ACCESS_API 195 select HAVE_RELIABLE_STACKTRACE 196 select HAVE_RSEQ 197 select HAVE_SAMPLE_FTRACE_DIRECT 198 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 199 select HAVE_SOFTIRQ_ON_OWN_STACK 200 select HAVE_SYSCALL_TRACEPOINTS 201 select HAVE_VIRT_CPU_ACCOUNTING 202 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 203 select IOMMU_HELPER if PCI 204 select IOMMU_SUPPORT if PCI 205 select MMU_GATHER_NO_GATHER 206 select MMU_GATHER_RCU_TABLE_FREE 207 select MODULES_USE_ELF_RELA 208 select NEED_DMA_MAP_STATE if PCI 209 select NEED_SG_DMA_LENGTH if PCI 210 select OLD_SIGACTION 211 select OLD_SIGSUSPEND3 212 select PCI_DOMAINS if PCI 213 select PCI_MSI if PCI 214 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 215 select SPARSE_IRQ 216 select SWIOTLB 217 select SYSCTL_EXCEPTION_TRACE 218 select THREAD_INFO_IN_TASK 219 select TRACE_IRQFLAGS_SUPPORT 220 select TTY 221 select VIRT_CPU_ACCOUNTING 222 select ZONE_DMA 223 # Note: keep the above list sorted alphabetically 224 225config SCHED_OMIT_FRAME_POINTER 226 def_bool y 227 228config PGTABLE_LEVELS 229 int 230 default 5 231 232source "kernel/livepatch/Kconfig" 233 234menu "Processor type and features" 235 236config HAVE_MARCH_Z10_FEATURES 237 def_bool n 238 239config HAVE_MARCH_Z196_FEATURES 240 def_bool n 241 select HAVE_MARCH_Z10_FEATURES 242 243config HAVE_MARCH_ZEC12_FEATURES 244 def_bool n 245 select HAVE_MARCH_Z196_FEATURES 246 247config HAVE_MARCH_Z13_FEATURES 248 def_bool n 249 select HAVE_MARCH_ZEC12_FEATURES 250 251config HAVE_MARCH_Z14_FEATURES 252 def_bool n 253 select HAVE_MARCH_Z13_FEATURES 254 255config HAVE_MARCH_Z15_FEATURES 256 def_bool n 257 select HAVE_MARCH_Z14_FEATURES 258 259config HAVE_MARCH_Z16_FEATURES 260 def_bool n 261 select HAVE_MARCH_Z15_FEATURES 262 263choice 264 prompt "Processor type" 265 default MARCH_Z196 266 267config MARCH_Z10 268 bool "IBM System z10" 269 select HAVE_MARCH_Z10_FEATURES 270 depends on $(cc-option,-march=z10) 271 help 272 Select this to enable optimizations for IBM System z10 (2097 and 2098 273 series). This is the oldest machine generation currently supported. 274 275config MARCH_Z196 276 bool "IBM zEnterprise 114 and 196" 277 select HAVE_MARCH_Z196_FEATURES 278 depends on $(cc-option,-march=z196) 279 help 280 Select this to enable optimizations for IBM zEnterprise 114 and 196 281 (2818 and 2817 series). The kernel will be slightly faster but will 282 not work on older machines. 283 284config MARCH_ZEC12 285 bool "IBM zBC12 and zEC12" 286 select HAVE_MARCH_ZEC12_FEATURES 287 depends on $(cc-option,-march=zEC12) 288 help 289 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 290 2827 series). The kernel will be slightly faster but will not work on 291 older machines. 292 293config MARCH_Z13 294 bool "IBM z13s and z13" 295 select HAVE_MARCH_Z13_FEATURES 296 depends on $(cc-option,-march=z13) 297 help 298 Select this to enable optimizations for IBM z13s and z13 (2965 and 299 2964 series). The kernel will be slightly faster but will not work on 300 older machines. 301 302config MARCH_Z14 303 bool "IBM z14 ZR1 and z14" 304 select HAVE_MARCH_Z14_FEATURES 305 depends on $(cc-option,-march=z14) 306 help 307 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 308 and 3906 series). The kernel will be slightly faster but will not 309 work on older machines. 310 311config MARCH_Z15 312 bool "IBM z15" 313 select HAVE_MARCH_Z15_FEATURES 314 depends on $(cc-option,-march=z15) 315 help 316 Select this to enable optimizations for IBM z15 (8562 317 and 8561 series). The kernel will be slightly faster but will not 318 work on older machines. 319 320config MARCH_Z16 321 bool "IBM z16" 322 select HAVE_MARCH_Z16_FEATURES 323 depends on $(cc-option,-march=z16) 324 help 325 Select this to enable optimizations for IBM z16 (3931 and 326 3932 series). 327 328endchoice 329 330config MARCH_Z10_TUNE 331 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 332 333config MARCH_Z196_TUNE 334 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 335 336config MARCH_ZEC12_TUNE 337 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 338 339config MARCH_Z13_TUNE 340 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 341 342config MARCH_Z14_TUNE 343 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 344 345config MARCH_Z15_TUNE 346 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 347 348config MARCH_Z16_TUNE 349 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 350 351choice 352 prompt "Tune code generation" 353 default TUNE_DEFAULT 354 help 355 Cause the compiler to tune (-mtune) the generated code for a machine. 356 This will make the code run faster on the selected machine but 357 somewhat slower on other machines. 358 This option only changes how the compiler emits instructions, not the 359 selection of instructions itself, so the resulting kernel will run on 360 all other machines. 361 362config TUNE_DEFAULT 363 bool "Default" 364 help 365 Tune the generated code for the target processor for which the kernel 366 will be compiled. 367 368config TUNE_Z10 369 bool "IBM System z10" 370 371config TUNE_Z196 372 bool "IBM zEnterprise 114 and 196" 373 depends on $(cc-option,-mtune=z196) 374 375config TUNE_ZEC12 376 bool "IBM zBC12 and zEC12" 377 depends on $(cc-option,-mtune=zEC12) 378 379config TUNE_Z13 380 bool "IBM z13s and z13" 381 depends on $(cc-option,-mtune=z13) 382 383config TUNE_Z14 384 bool "IBM z14 ZR1 and z14" 385 depends on $(cc-option,-mtune=z14) 386 387config TUNE_Z15 388 bool "IBM z15" 389 depends on $(cc-option,-mtune=z15) 390 391config TUNE_Z16 392 bool "IBM z16" 393 depends on $(cc-option,-mtune=z16) 394 395endchoice 396 397config 64BIT 398 def_bool y 399 400config COMMAND_LINE_SIZE 401 int "Maximum size of kernel command line" 402 default 4096 403 range 896 1048576 404 help 405 This allows you to specify the maximum length of the kernel command 406 line. 407 408config COMPAT 409 def_bool y 410 prompt "Kernel support for 31 bit emulation" 411 select ARCH_WANT_OLD_COMPAT_IPC 412 select COMPAT_OLD_SIGACTION 413 select HAVE_UID16 414 depends on MULTIUSER 415 depends on !CC_IS_CLANG 416 help 417 Select this option if you want to enable your system kernel to 418 handle system-calls from ELF binaries for 31 bit ESA. This option 419 (and some other stuff like libraries and such) is needed for 420 executing 31 bit applications. It is safe to say "Y". 421 422config SMP 423 def_bool y 424 425config NR_CPUS 426 int "Maximum number of CPUs (2-512)" 427 range 2 512 428 default "64" 429 help 430 This allows you to specify the maximum number of CPUs which this 431 kernel will support. The maximum supported value is 512 and the 432 minimum value which makes sense is 2. 433 434 This is purely to save memory - each supported CPU adds 435 approximately sixteen kilobytes to the kernel image. 436 437config HOTPLUG_CPU 438 def_bool y 439 440config NUMA 441 bool "NUMA support" 442 depends on SCHED_TOPOLOGY 443 default n 444 help 445 Enable NUMA support 446 447 This option adds NUMA support to the kernel. 448 449config NODES_SHIFT 450 int 451 depends on NUMA 452 default "1" 453 454config SCHED_SMT 455 def_bool n 456 457config SCHED_MC 458 def_bool n 459 460config SCHED_BOOK 461 def_bool n 462 463config SCHED_DRAWER 464 def_bool n 465 466config SCHED_TOPOLOGY 467 def_bool y 468 prompt "Topology scheduler support" 469 select SCHED_SMT 470 select SCHED_MC 471 select SCHED_BOOK 472 select SCHED_DRAWER 473 help 474 Topology scheduler support improves the CPU scheduler's decision 475 making when dealing with machines that have multi-threading, 476 multiple cores or multiple books. 477 478source "kernel/Kconfig.hz" 479 480config KEXEC 481 def_bool y 482 select KEXEC_CORE 483 484config KEXEC_FILE 485 bool "kexec file based system call" 486 select KEXEC_CORE 487 select BUILD_BIN2C 488 depends on CRYPTO 489 depends on CRYPTO_SHA256 490 depends on CRYPTO_SHA256_S390 491 help 492 Enable the kexec file based system call. In contrast to the normal 493 kexec system call this system call takes file descriptors for the 494 kernel and initramfs as arguments. 495 496config ARCH_HAS_KEXEC_PURGATORY 497 def_bool y 498 depends on KEXEC_FILE 499 500config KEXEC_SIG 501 bool "Verify kernel signature during kexec_file_load() syscall" 502 depends on KEXEC_FILE && MODULE_SIG_FORMAT 503 help 504 This option makes kernel signature verification mandatory for 505 the kexec_file_load() syscall. 506 507 In addition to that option, you need to enable signature 508 verification for the corresponding kernel image type being 509 loaded in order for this to work. 510 511config ARCH_RANDOM 512 def_bool y 513 prompt "s390 architectural random number generation API" 514 help 515 Enable the s390 architectural random number generation API 516 to provide random data for all consumers within the Linux 517 kernel. 518 519 When enabled the arch_random_* functions declared in linux/random.h 520 are implemented. The implementation is based on the s390 CPACF 521 instruction subfunction TRNG which provides a real true random 522 number generator. 523 524 If unsure, say Y. 525 526config KERNEL_NOBP 527 def_bool n 528 prompt "Enable modified branch prediction for the kernel by default" 529 help 530 If this option is selected the kernel will switch to a modified 531 branch prediction mode if the firmware interface is available. 532 The modified branch prediction mode improves the behaviour in 533 regard to speculative execution. 534 535 With the option enabled the kernel parameter "nobp=0" or "nospec" 536 can be used to run the kernel in the normal branch prediction mode. 537 538 With the option disabled the modified branch prediction mode is 539 enabled with the "nobp=1" kernel parameter. 540 541 If unsure, say N. 542 543config EXPOLINE 544 def_bool n 545 depends on $(cc-option,-mindirect-branch=thunk) 546 prompt "Avoid speculative indirect branches in the kernel" 547 help 548 Compile the kernel with the expoline compiler options to guard 549 against kernel-to-user data leaks by avoiding speculative indirect 550 branches. 551 Requires a compiler with -mindirect-branch=thunk support for full 552 protection. The kernel may run slower. 553 554 If unsure, say N. 555 556config EXPOLINE_EXTERN 557 def_bool n 558 depends on EXPOLINE 559 depends on CC_IS_GCC && GCC_VERSION >= 110200 560 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 561 prompt "Generate expolines as extern functions." 562 help 563 This option is required for some tooling like kpatch. The kernel is 564 compiled with -mindirect-branch=thunk-extern and requires a newer 565 compiler. 566 567 If unsure, say N. 568 569choice 570 prompt "Expoline default" 571 depends on EXPOLINE 572 default EXPOLINE_FULL 573 574config EXPOLINE_OFF 575 bool "spectre_v2=off" 576 577config EXPOLINE_AUTO 578 bool "spectre_v2=auto" 579 580config EXPOLINE_FULL 581 bool "spectre_v2=on" 582 583endchoice 584 585config RELOCATABLE 586 bool "Build a relocatable kernel" 587 default y 588 help 589 This builds a kernel image that retains relocation information 590 so it can be loaded at an arbitrary address. 591 The kernel is linked as a position-independent executable (PIE) 592 and contains dynamic relocations which are processed early in the 593 bootup process. 594 The relocations make the kernel image about 15% larger (compressed 595 10%), but are discarded at runtime. 596 597config RANDOMIZE_BASE 598 bool "Randomize the address of the kernel image (KASLR)" 599 depends on RELOCATABLE 600 default y 601 help 602 In support of Kernel Address Space Layout Randomization (KASLR), 603 this randomizes the address at which the kernel image is loaded, 604 as a security feature that deters exploit attempts relying on 605 knowledge of the location of kernel internals. 606 607endmenu 608 609menu "Memory setup" 610 611config ARCH_SPARSEMEM_ENABLE 612 def_bool y 613 select SPARSEMEM_VMEMMAP_ENABLE 614 select SPARSEMEM_VMEMMAP 615 616config ARCH_SPARSEMEM_DEFAULT 617 def_bool y 618 619config MAX_PHYSMEM_BITS 620 int "Maximum size of supported physical memory in bits (42-53)" 621 range 42 53 622 default "46" 623 help 624 This option specifies the maximum supported size of physical memory 625 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 626 Increasing the number of bits also increases the kernel image size. 627 By default 46 bits (64TB) are supported. 628 629config CHECK_STACK 630 def_bool y 631 depends on !VMAP_STACK 632 prompt "Detect kernel stack overflow" 633 help 634 This option enables the compiler option -mstack-guard and 635 -mstack-size if they are available. If the compiler supports them 636 it will emit additional code to each function prolog to trigger 637 an illegal operation if the kernel stack is about to overflow. 638 639 Say N if you are unsure. 640 641config STACK_GUARD 642 int "Size of the guard area (128-1024)" 643 range 128 1024 644 depends on CHECK_STACK 645 default "256" 646 help 647 This allows you to specify the size of the guard area at the lower 648 end of the kernel stack. If the kernel stack points into the guard 649 area on function entry an illegal operation is triggered. The size 650 needs to be a power of 2. Please keep in mind that the size of an 651 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 652 The minimum size for the stack guard should be 256 for 31 bit and 653 512 for 64 bit. 654 655endmenu 656 657menu "I/O subsystem" 658 659config QDIO 660 def_tristate y 661 prompt "QDIO support" 662 help 663 This driver provides the Queued Direct I/O base support for 664 IBM System z. 665 666 To compile this driver as a module, choose M here: the 667 module will be called qdio. 668 669 If unsure, say Y. 670 671if PCI 672 673config PCI_NR_FUNCTIONS 674 int "Maximum number of PCI functions (1-4096)" 675 range 1 4096 676 default "512" 677 help 678 This allows you to specify the maximum number of PCI functions which 679 this kernel will support. 680 681endif # PCI 682 683config HAS_IOMEM 684 def_bool PCI 685 686config CHSC_SCH 687 def_tristate m 688 prompt "Support for CHSC subchannels" 689 help 690 This driver allows usage of CHSC subchannels. A CHSC subchannel 691 is usually present on LPAR only. 692 The driver creates a device /dev/chsc, which may be used to 693 obtain I/O configuration information about the machine and 694 to issue asynchronous chsc commands (DANGEROUS). 695 You will usually only want to use this interface on a special 696 LPAR designated for system management. 697 698 To compile this driver as a module, choose M here: the 699 module will be called chsc_sch. 700 701 If unsure, say N. 702 703config SCM_BUS 704 def_bool y 705 prompt "SCM bus driver" 706 help 707 Bus driver for Storage Class Memory. 708 709config EADM_SCH 710 def_tristate m 711 prompt "Support for EADM subchannels" 712 depends on SCM_BUS 713 help 714 This driver allows usage of EADM subchannels. EADM subchannels act 715 as a communication vehicle for SCM increments. 716 717 To compile this driver as a module, choose M here: the 718 module will be called eadm_sch. 719 720config VFIO_CCW 721 def_tristate n 722 prompt "Support for VFIO-CCW subchannels" 723 depends on S390_CCW_IOMMU && VFIO_MDEV 724 help 725 This driver allows usage of I/O subchannels via VFIO-CCW. 726 727 To compile this driver as a module, choose M here: the 728 module will be called vfio_ccw. 729 730config VFIO_AP 731 def_tristate n 732 prompt "VFIO support for AP devices" 733 depends on S390_AP_IOMMU && VFIO_MDEV && KVM 734 depends on ZCRYPT 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