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 depends on CRYPTO 488 depends on CRYPTO_SHA256 489 depends on CRYPTO_SHA256_S390 490 help 491 Enable the kexec file based system call. In contrast to the normal 492 kexec system call this system call takes file descriptors for the 493 kernel and initramfs as arguments. 494 495config ARCH_HAS_KEXEC_PURGATORY 496 def_bool y 497 depends on KEXEC_FILE 498 499config KEXEC_SIG 500 bool "Verify kernel signature during kexec_file_load() syscall" 501 depends on KEXEC_FILE && MODULE_SIG_FORMAT 502 help 503 This option makes kernel signature verification mandatory for 504 the kexec_file_load() syscall. 505 506 In addition to that option, you need to enable signature 507 verification for the corresponding kernel image type being 508 loaded in order for this to work. 509 510config KERNEL_NOBP 511 def_bool n 512 prompt "Enable modified branch prediction for the kernel by default" 513 help 514 If this option is selected the kernel will switch to a modified 515 branch prediction mode if the firmware interface is available. 516 The modified branch prediction mode improves the behaviour in 517 regard to speculative execution. 518 519 With the option enabled the kernel parameter "nobp=0" or "nospec" 520 can be used to run the kernel in the normal branch prediction mode. 521 522 With the option disabled the modified branch prediction mode is 523 enabled with the "nobp=1" kernel parameter. 524 525 If unsure, say N. 526 527config EXPOLINE 528 def_bool n 529 depends on $(cc-option,-mindirect-branch=thunk) 530 prompt "Avoid speculative indirect branches in the kernel" 531 help 532 Compile the kernel with the expoline compiler options to guard 533 against kernel-to-user data leaks by avoiding speculative indirect 534 branches. 535 Requires a compiler with -mindirect-branch=thunk support for full 536 protection. The kernel may run slower. 537 538 If unsure, say N. 539 540config EXPOLINE_EXTERN 541 def_bool n 542 depends on EXPOLINE 543 depends on CC_IS_GCC && GCC_VERSION >= 110200 544 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 545 prompt "Generate expolines as extern functions." 546 help 547 This option is required for some tooling like kpatch. The kernel is 548 compiled with -mindirect-branch=thunk-extern and requires a newer 549 compiler. 550 551 If unsure, say N. 552 553choice 554 prompt "Expoline default" 555 depends on EXPOLINE 556 default EXPOLINE_FULL 557 558config EXPOLINE_OFF 559 bool "spectre_v2=off" 560 561config EXPOLINE_AUTO 562 bool "spectre_v2=auto" 563 564config EXPOLINE_FULL 565 bool "spectre_v2=on" 566 567endchoice 568 569config RELOCATABLE 570 bool "Build a relocatable kernel" 571 default y 572 help 573 This builds a kernel image that retains relocation information 574 so it can be loaded at an arbitrary address. 575 The kernel is linked as a position-independent executable (PIE) 576 and contains dynamic relocations which are processed early in the 577 bootup process. 578 The relocations make the kernel image about 15% larger (compressed 579 10%), but are discarded at runtime. 580 581config RANDOMIZE_BASE 582 bool "Randomize the address of the kernel image (KASLR)" 583 depends on RELOCATABLE 584 default y 585 help 586 In support of Kernel Address Space Layout Randomization (KASLR), 587 this randomizes the address at which the kernel image is loaded, 588 as a security feature that deters exploit attempts relying on 589 knowledge of the location of kernel internals. 590 591endmenu 592 593menu "Memory setup" 594 595config ARCH_SPARSEMEM_ENABLE 596 def_bool y 597 select SPARSEMEM_VMEMMAP_ENABLE 598 select SPARSEMEM_VMEMMAP 599 600config ARCH_SPARSEMEM_DEFAULT 601 def_bool y 602 603config MAX_PHYSMEM_BITS 604 int "Maximum size of supported physical memory in bits (42-53)" 605 range 42 53 606 default "46" 607 help 608 This option specifies the maximum supported size of physical memory 609 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 610 Increasing the number of bits also increases the kernel image size. 611 By default 46 bits (64TB) are supported. 612 613config CHECK_STACK 614 def_bool y 615 depends on !VMAP_STACK 616 prompt "Detect kernel stack overflow" 617 help 618 This option enables the compiler option -mstack-guard and 619 -mstack-size if they are available. If the compiler supports them 620 it will emit additional code to each function prolog to trigger 621 an illegal operation if the kernel stack is about to overflow. 622 623 Say N if you are unsure. 624 625config STACK_GUARD 626 int "Size of the guard area (128-1024)" 627 range 128 1024 628 depends on CHECK_STACK 629 default "256" 630 help 631 This allows you to specify the size of the guard area at the lower 632 end of the kernel stack. If the kernel stack points into the guard 633 area on function entry an illegal operation is triggered. The size 634 needs to be a power of 2. Please keep in mind that the size of an 635 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 636 The minimum size for the stack guard should be 256 for 31 bit and 637 512 for 64 bit. 638 639endmenu 640 641menu "I/O subsystem" 642 643config QDIO 644 def_tristate y 645 prompt "QDIO support" 646 help 647 This driver provides the Queued Direct I/O base support for 648 IBM System z. 649 650 To compile this driver as a module, choose M here: the 651 module will be called qdio. 652 653 If unsure, say Y. 654 655if PCI 656 657config PCI_NR_FUNCTIONS 658 int "Maximum number of PCI functions (1-4096)" 659 range 1 4096 660 default "512" 661 help 662 This allows you to specify the maximum number of PCI functions which 663 this kernel will support. 664 665endif # PCI 666 667config HAS_IOMEM 668 def_bool PCI 669 670config CHSC_SCH 671 def_tristate m 672 prompt "Support for CHSC subchannels" 673 help 674 This driver allows usage of CHSC subchannels. A CHSC subchannel 675 is usually present on LPAR only. 676 The driver creates a device /dev/chsc, which may be used to 677 obtain I/O configuration information about the machine and 678 to issue asynchronous chsc commands (DANGEROUS). 679 You will usually only want to use this interface on a special 680 LPAR designated for system management. 681 682 To compile this driver as a module, choose M here: the 683 module will be called chsc_sch. 684 685 If unsure, say N. 686 687config SCM_BUS 688 def_bool y 689 prompt "SCM bus driver" 690 help 691 Bus driver for Storage Class Memory. 692 693config EADM_SCH 694 def_tristate m 695 prompt "Support for EADM subchannels" 696 depends on SCM_BUS 697 help 698 This driver allows usage of EADM subchannels. EADM subchannels act 699 as a communication vehicle for SCM increments. 700 701 To compile this driver as a module, choose M here: the 702 module will be called eadm_sch. 703 704config VFIO_CCW 705 def_tristate n 706 prompt "Support for VFIO-CCW subchannels" 707 depends on S390_CCW_IOMMU && VFIO_MDEV 708 help 709 This driver allows usage of I/O subchannels via VFIO-CCW. 710 711 To compile this driver as a module, choose M here: the 712 module will be called vfio_ccw. 713 714config VFIO_AP 715 def_tristate n 716 prompt "VFIO support for AP devices" 717 depends on S390_AP_IOMMU && VFIO_MDEV && KVM 718 depends on ZCRYPT 719 help 720 This driver grants access to Adjunct Processor (AP) devices 721 via the VFIO mediated device interface. 722 723 To compile this driver as a module, choose M here: the module 724 will be called vfio_ap. 725 726endmenu 727 728menu "Dump support" 729 730config CRASH_DUMP 731 bool "kernel crash dumps" 732 select KEXEC 733 help 734 Generate crash dump after being started by kexec. 735 Crash dump kernels are loaded in the main kernel with kexec-tools 736 into a specially reserved region and then later executed after 737 a crash by kdump/kexec. 738 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 739 This option also enables s390 zfcpdump. 740 See also <file:Documentation/s390/zfcpdump.rst> 741 742endmenu 743 744config CCW 745 def_bool y 746 747config HAVE_PNETID 748 tristate 749 default (SMC || CCWGROUP) 750 751menu "Virtualization" 752 753config PROTECTED_VIRTUALIZATION_GUEST 754 def_bool n 755 prompt "Protected virtualization guest support" 756 help 757 Select this option, if you want to be able to run this 758 kernel as a protected virtualization KVM guest. 759 Protected virtualization capable machines have a mini hypervisor 760 located at machine level (an ultravisor). With help of the 761 Ultravisor, KVM will be able to run "protected" VMs, special 762 VMs whose memory and management data are unavailable to KVM. 763 764config PFAULT 765 def_bool y 766 prompt "Pseudo page fault support" 767 help 768 Select this option, if you want to use PFAULT pseudo page fault 769 handling under VM. If running native or in LPAR, this option 770 has no effect. If your VM does not support PFAULT, PAGEEX 771 pseudo page fault handling will be used. 772 Note that VM 4.2 supports PFAULT but has a bug in its 773 implementation that causes some problems. 774 Everybody who wants to run Linux under VM != VM4.2 should select 775 this option. 776 777config CMM 778 def_tristate n 779 prompt "Cooperative memory management" 780 help 781 Select this option, if you want to enable the kernel interface 782 to reduce the memory size of the system. This is accomplished 783 by allocating pages of memory and put them "on hold". This only 784 makes sense for a system running under VM where the unused pages 785 will be reused by VM for other guest systems. The interface 786 allows an external monitor to balance memory of many systems. 787 Everybody who wants to run Linux under VM should select this 788 option. 789 790config CMM_IUCV 791 def_bool y 792 prompt "IUCV special message interface to cooperative memory management" 793 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 794 help 795 Select this option to enable the special message interface to 796 the cooperative memory management. 797 798config APPLDATA_BASE 799 def_bool n 800 prompt "Linux - VM Monitor Stream, base infrastructure" 801 depends on PROC_SYSCTL 802 help 803 This provides a kernel interface for creating and updating z/VM APPLDATA 804 monitor records. The monitor records are updated at certain time 805 intervals, once the timer is started. 806 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 807 i.e. enables or disables monitoring on the Linux side. 808 A custom interval value (in seconds) can be written to 809 /proc/appldata/interval. 810 811 Defaults are 60 seconds interval and timer off. 812 The /proc entries can also be read from, showing the current settings. 813 814config APPLDATA_MEM 815 def_tristate m 816 prompt "Monitor memory management statistics" 817 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 818 help 819 This provides memory management related data to the Linux - VM Monitor 820 Stream, like paging/swapping rate, memory utilisation, etc. 821 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 822 APPLDATA monitor record, i.e. enables or disables monitoring this record 823 on the z/VM side. 824 825 Default is disabled. 826 The /proc entry can also be read from, showing the current settings. 827 828 This can also be compiled as a module, which will be called 829 appldata_mem.o. 830 831config APPLDATA_OS 832 def_tristate m 833 prompt "Monitor OS statistics" 834 depends on APPLDATA_BASE 835 help 836 This provides OS related data to the Linux - VM Monitor Stream, like 837 CPU utilisation, etc. 838 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 839 APPLDATA monitor record, i.e. enables or disables monitoring this record 840 on the z/VM side. 841 842 Default is disabled. 843 This can also be compiled as a module, which will be called 844 appldata_os.o. 845 846config APPLDATA_NET_SUM 847 def_tristate m 848 prompt "Monitor overall network statistics" 849 depends on APPLDATA_BASE && NET 850 help 851 This provides network related data to the Linux - VM Monitor Stream, 852 currently there is only a total sum of network I/O statistics, no 853 per-interface data. 854 Writing 1 or 0 to /proc/appldata/net_sum 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_net_sum.o. 861 862config S390_HYPFS_FS 863 def_bool y 864 prompt "s390 hypervisor file system support" 865 select SYS_HYPERVISOR 866 help 867 This is a virtual file system intended to provide accounting 868 information in an s390 hypervisor environment. 869 870source "arch/s390/kvm/Kconfig" 871 872config S390_GUEST 873 def_bool y 874 prompt "s390 support for virtio devices" 875 select TTY 876 select VIRTUALIZATION 877 select VIRTIO 878 help 879 Enabling this option adds support for virtio based paravirtual device 880 drivers on s390. 881 882 Select this option if you want to run the kernel as a guest under 883 the KVM hypervisor. 884 885endmenu 886 887config S390_MODULES_SANITY_TEST_HELPERS 888 def_bool n 889 890menu "Selftests" 891 892config S390_UNWIND_SELFTEST 893 def_tristate n 894 depends on KUNIT 895 default KUNIT_ALL_TESTS 896 prompt "Test unwind functions" 897 help 898 This option enables s390 specific stack unwinder testing kernel 899 module. This option is not useful for distributions or general 900 kernels, but only for kernel developers working on architecture code. 901 902 Say N if you are unsure. 903 904config S390_KPROBES_SANITY_TEST 905 def_tristate n 906 prompt "Enable s390 specific kprobes tests" 907 depends on KPROBES 908 depends on KUNIT 909 help 910 This option enables an s390 specific kprobes test module. This option 911 is not useful for distributions or general kernels, but only for kernel 912 developers working on architecture code. 913 914 Say N if you are unsure. 915 916config S390_MODULES_SANITY_TEST 917 def_tristate n 918 depends on KUNIT 919 default KUNIT_ALL_TESTS 920 prompt "Enable s390 specific modules tests" 921 select S390_MODULES_SANITY_TEST_HELPERS 922 help 923 This option enables an s390 specific modules test. This option is 924 not useful for distributions or general kernels, but only for 925 kernel developers working on architecture code. 926 927 Say N if you are unsure. 928endmenu 929