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_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 62 select ARCH_ENABLE_MEMORY_HOTREMOVE 63 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 64 select ARCH_HAS_CURRENT_STACK_POINTER 65 select ARCH_HAS_DEBUG_VM_PGTABLE 66 select ARCH_HAS_DEBUG_WX 67 select ARCH_HAS_DEVMEM_IS_ALLOWED 68 select ARCH_HAS_ELF_RANDOMIZE 69 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 70 select ARCH_HAS_FORTIFY_SOURCE 71 select ARCH_HAS_GCOV_PROFILE_ALL 72 select ARCH_HAS_GIGANTIC_PAGE 73 select ARCH_HAS_KCOV 74 select ARCH_HAS_MEM_ENCRYPT 75 select ARCH_HAS_PTE_SPECIAL 76 select ARCH_HAS_SCALED_CPUTIME 77 select ARCH_HAS_SET_MEMORY 78 select ARCH_HAS_STRICT_KERNEL_RWX 79 select ARCH_HAS_STRICT_MODULE_RWX 80 select ARCH_HAS_SYSCALL_WRAPPER 81 select ARCH_HAS_UBSAN_SANITIZE_ALL 82 select ARCH_HAS_VDSO_DATA 83 select ARCH_HAVE_NMI_SAFE_CMPXCHG 84 select ARCH_INLINE_READ_LOCK 85 select ARCH_INLINE_READ_LOCK_BH 86 select ARCH_INLINE_READ_LOCK_IRQ 87 select ARCH_INLINE_READ_LOCK_IRQSAVE 88 select ARCH_INLINE_READ_TRYLOCK 89 select ARCH_INLINE_READ_UNLOCK 90 select ARCH_INLINE_READ_UNLOCK_BH 91 select ARCH_INLINE_READ_UNLOCK_IRQ 92 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 93 select ARCH_INLINE_SPIN_LOCK 94 select ARCH_INLINE_SPIN_LOCK_BH 95 select ARCH_INLINE_SPIN_LOCK_IRQ 96 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 97 select ARCH_INLINE_SPIN_TRYLOCK 98 select ARCH_INLINE_SPIN_TRYLOCK_BH 99 select ARCH_INLINE_SPIN_UNLOCK 100 select ARCH_INLINE_SPIN_UNLOCK_BH 101 select ARCH_INLINE_SPIN_UNLOCK_IRQ 102 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 103 select ARCH_INLINE_WRITE_LOCK 104 select ARCH_INLINE_WRITE_LOCK_BH 105 select ARCH_INLINE_WRITE_LOCK_IRQ 106 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 107 select ARCH_INLINE_WRITE_TRYLOCK 108 select ARCH_INLINE_WRITE_UNLOCK 109 select ARCH_INLINE_WRITE_UNLOCK_BH 110 select ARCH_INLINE_WRITE_UNLOCK_IRQ 111 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 112 select ARCH_STACKWALK 113 select ARCH_SUPPORTS_ATOMIC_RMW 114 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 115 select ARCH_SUPPORTS_HUGETLBFS 116 select ARCH_SUPPORTS_NUMA_BALANCING 117 select ARCH_USE_BUILTIN_BSWAP 118 select ARCH_USE_CMPXCHG_LOCKREF 119 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 120 select ARCH_WANTS_NO_INSTR 121 select ARCH_WANT_DEFAULT_BPF_JIT 122 select ARCH_WANT_IPC_PARSE_VERSION 123 select BUILDTIME_TABLE_SORT 124 select CLONE_BACKWARDS2 125 select DMA_OPS if PCI 126 select DYNAMIC_FTRACE if FUNCTION_TRACER 127 select GENERIC_ALLOCATOR 128 select GENERIC_CPU_AUTOPROBE 129 select GENERIC_CPU_VULNERABILITIES 130 select GENERIC_ENTRY 131 select GENERIC_GETTIMEOFDAY 132 select GENERIC_PTDUMP 133 select GENERIC_SMP_IDLE_THREAD 134 select GENERIC_TIME_VSYSCALL 135 select GENERIC_VDSO_TIME_NS 136 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 137 select HAVE_ARCH_AUDITSYSCALL 138 select HAVE_ARCH_JUMP_LABEL 139 select HAVE_ARCH_JUMP_LABEL_RELATIVE 140 select HAVE_ARCH_KASAN 141 select HAVE_ARCH_KASAN_VMALLOC 142 select HAVE_ARCH_KCSAN 143 select HAVE_ARCH_KFENCE 144 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 145 select HAVE_ARCH_SECCOMP_FILTER 146 select HAVE_ARCH_SOFT_DIRTY 147 select HAVE_ARCH_TRACEHOOK 148 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 149 select HAVE_ARCH_VMAP_STACK 150 select HAVE_ASM_MODVERSIONS 151 select HAVE_CMPXCHG_DOUBLE 152 select HAVE_CMPXCHG_LOCAL 153 select HAVE_DEBUG_KMEMLEAK 154 select HAVE_DMA_CONTIGUOUS 155 select HAVE_DYNAMIC_FTRACE 156 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 157 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 158 select HAVE_DYNAMIC_FTRACE_WITH_REGS 159 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 160 select HAVE_EFFICIENT_UNALIGNED_ACCESS 161 select HAVE_FAST_GUP 162 select HAVE_FENTRY 163 select HAVE_FTRACE_MCOUNT_RECORD 164 select HAVE_FUNCTION_ARG_ACCESS_API 165 select HAVE_FUNCTION_ERROR_INJECTION 166 select HAVE_FUNCTION_GRAPH_TRACER 167 select HAVE_FUNCTION_TRACER 168 select HAVE_GCC_PLUGINS 169 select HAVE_GENERIC_VDSO 170 select HAVE_IOREMAP_PROT if PCI 171 select HAVE_KERNEL_BZIP2 172 select HAVE_KERNEL_GZIP 173 select HAVE_KERNEL_LZ4 174 select HAVE_KERNEL_LZMA 175 select HAVE_KERNEL_LZO 176 select HAVE_KERNEL_UNCOMPRESSED 177 select HAVE_KERNEL_XZ 178 select HAVE_KERNEL_ZSTD 179 select HAVE_KPROBES 180 select HAVE_KPROBES_ON_FTRACE 181 select HAVE_KRETPROBES 182 select HAVE_KVM 183 select HAVE_LIVEPATCH 184 select HAVE_MEMBLOCK_PHYS_MAP 185 select HAVE_MOD_ARCH_SPECIFIC 186 select HAVE_NMI 187 select HAVE_NOP_MCOUNT 188 select HAVE_PCI 189 select HAVE_PERF_EVENTS 190 select HAVE_PERF_REGS 191 select HAVE_PERF_USER_STACK_DUMP 192 select HAVE_REGS_AND_STACK_ACCESS_API 193 select HAVE_RELIABLE_STACKTRACE 194 select HAVE_RSEQ 195 select HAVE_SAMPLE_FTRACE_DIRECT 196 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 197 select HAVE_SOFTIRQ_ON_OWN_STACK 198 select HAVE_SYSCALL_TRACEPOINTS 199 select HAVE_VIRT_CPU_ACCOUNTING 200 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 201 select IOMMU_HELPER if PCI 202 select IOMMU_SUPPORT if PCI 203 select MMU_GATHER_NO_GATHER 204 select MMU_GATHER_RCU_TABLE_FREE 205 select MODULES_USE_ELF_RELA 206 select NEED_DMA_MAP_STATE if PCI 207 select NEED_SG_DMA_LENGTH if PCI 208 select OLD_SIGACTION 209 select OLD_SIGSUSPEND3 210 select PCI_DOMAINS if PCI 211 select PCI_MSI if PCI 212 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 213 select SPARSE_IRQ 214 select SWIOTLB 215 select SYSCTL_EXCEPTION_TRACE 216 select THREAD_INFO_IN_TASK 217 select TRACE_IRQFLAGS_SUPPORT 218 select TTY 219 select VIRT_CPU_ACCOUNTING 220 select ZONE_DMA 221 # Note: keep the above list sorted alphabetically 222 223config SCHED_OMIT_FRAME_POINTER 224 def_bool y 225 226config PGTABLE_LEVELS 227 int 228 default 5 229 230source "kernel/livepatch/Kconfig" 231 232menu "Processor type and features" 233 234config HAVE_MARCH_Z10_FEATURES 235 def_bool n 236 237config HAVE_MARCH_Z196_FEATURES 238 def_bool n 239 select HAVE_MARCH_Z10_FEATURES 240 241config HAVE_MARCH_ZEC12_FEATURES 242 def_bool n 243 select HAVE_MARCH_Z196_FEATURES 244 245config HAVE_MARCH_Z13_FEATURES 246 def_bool n 247 select HAVE_MARCH_ZEC12_FEATURES 248 249config HAVE_MARCH_Z14_FEATURES 250 def_bool n 251 select HAVE_MARCH_Z13_FEATURES 252 253config HAVE_MARCH_Z15_FEATURES 254 def_bool n 255 select HAVE_MARCH_Z14_FEATURES 256 257choice 258 prompt "Processor type" 259 default MARCH_Z196 260 261config MARCH_Z10 262 bool "IBM System z10" 263 select HAVE_MARCH_Z10_FEATURES 264 depends on $(cc-option,-march=z10) 265 help 266 Select this to enable optimizations for IBM System z10 (2097 and 2098 267 series). This is the oldest machine generation currently supported. 268 269config MARCH_Z196 270 bool "IBM zEnterprise 114 and 196" 271 select HAVE_MARCH_Z196_FEATURES 272 depends on $(cc-option,-march=z196) 273 help 274 Select this to enable optimizations for IBM zEnterprise 114 and 196 275 (2818 and 2817 series). The kernel will be slightly faster but will 276 not work on older machines. 277 278config MARCH_ZEC12 279 bool "IBM zBC12 and zEC12" 280 select HAVE_MARCH_ZEC12_FEATURES 281 depends on $(cc-option,-march=zEC12) 282 help 283 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 284 2827 series). The kernel will be slightly faster but will not work on 285 older machines. 286 287config MARCH_Z13 288 bool "IBM z13s and z13" 289 select HAVE_MARCH_Z13_FEATURES 290 depends on $(cc-option,-march=z13) 291 help 292 Select this to enable optimizations for IBM z13s and z13 (2965 and 293 2964 series). The kernel will be slightly faster but will not work on 294 older machines. 295 296config MARCH_Z14 297 bool "IBM z14 ZR1 and z14" 298 select HAVE_MARCH_Z14_FEATURES 299 depends on $(cc-option,-march=z14) 300 help 301 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 302 and 3906 series). The kernel will be slightly faster but will not 303 work on older machines. 304 305config MARCH_Z15 306 bool "IBM z15" 307 select HAVE_MARCH_Z15_FEATURES 308 depends on $(cc-option,-march=z15) 309 help 310 Select this to enable optimizations for IBM z15 (8562 311 and 8561 series). The kernel will be slightly faster but will not 312 work on older machines. 313 314endchoice 315 316config MARCH_Z10_TUNE 317 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 318 319config MARCH_Z196_TUNE 320 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 321 322config MARCH_ZEC12_TUNE 323 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 324 325config MARCH_Z13_TUNE 326 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 327 328config MARCH_Z14_TUNE 329 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 330 331config MARCH_Z15_TUNE 332 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 333 334choice 335 prompt "Tune code generation" 336 default TUNE_DEFAULT 337 help 338 Cause the compiler to tune (-mtune) the generated code for a machine. 339 This will make the code run faster on the selected machine but 340 somewhat slower on other machines. 341 This option only changes how the compiler emits instructions, not the 342 selection of instructions itself, so the resulting kernel will run on 343 all other machines. 344 345config TUNE_DEFAULT 346 bool "Default" 347 help 348 Tune the generated code for the target processor for which the kernel 349 will be compiled. 350 351config TUNE_Z10 352 bool "IBM System z10" 353 354config TUNE_Z196 355 bool "IBM zEnterprise 114 and 196" 356 depends on $(cc-option,-mtune=z196) 357 358config TUNE_ZEC12 359 bool "IBM zBC12 and zEC12" 360 depends on $(cc-option,-mtune=zEC12) 361 362config TUNE_Z13 363 bool "IBM z13s and z13" 364 depends on $(cc-option,-mtune=z13) 365 366config TUNE_Z14 367 bool "IBM z14 ZR1 and z14" 368 depends on $(cc-option,-mtune=z14) 369 370config TUNE_Z15 371 bool "IBM z15" 372 depends on $(cc-option,-mtune=z15) 373 374endchoice 375 376config 64BIT 377 def_bool y 378 379config COMMAND_LINE_SIZE 380 int "Maximum size of kernel command line" 381 default 4096 382 range 896 1048576 383 help 384 This allows you to specify the maximum length of the kernel command 385 line. 386 387config COMPAT 388 def_bool y 389 prompt "Kernel support for 31 bit emulation" 390 select ARCH_WANT_OLD_COMPAT_IPC 391 select COMPAT_OLD_SIGACTION 392 select HAVE_UID16 393 depends on MULTIUSER 394 depends on !CC_IS_CLANG 395 help 396 Select this option if you want to enable your system kernel to 397 handle system-calls from ELF binaries for 31 bit ESA. This option 398 (and some other stuff like libraries and such) is needed for 399 executing 31 bit applications. It is safe to say "Y". 400 401config SYSVIPC_COMPAT 402 def_bool y if COMPAT && SYSVIPC 403 404config SMP 405 def_bool y 406 407config NR_CPUS 408 int "Maximum number of CPUs (2-512)" 409 range 2 512 410 default "64" 411 help 412 This allows you to specify the maximum number of CPUs which this 413 kernel will support. The maximum supported value is 512 and the 414 minimum value which makes sense is 2. 415 416 This is purely to save memory - each supported CPU adds 417 approximately sixteen kilobytes to the kernel image. 418 419config HOTPLUG_CPU 420 def_bool y 421 422config NUMA 423 bool "NUMA support" 424 depends on SCHED_TOPOLOGY 425 default n 426 help 427 Enable NUMA support 428 429 This option adds NUMA support to the kernel. 430 431config NODES_SHIFT 432 int 433 depends on NUMA 434 default "1" 435 436config SCHED_SMT 437 def_bool n 438 439config SCHED_MC 440 def_bool n 441 442config SCHED_BOOK 443 def_bool n 444 445config SCHED_DRAWER 446 def_bool n 447 448config SCHED_TOPOLOGY 449 def_bool y 450 prompt "Topology scheduler support" 451 select SCHED_SMT 452 select SCHED_MC 453 select SCHED_BOOK 454 select SCHED_DRAWER 455 help 456 Topology scheduler support improves the CPU scheduler's decision 457 making when dealing with machines that have multi-threading, 458 multiple cores or multiple books. 459 460source "kernel/Kconfig.hz" 461 462config KEXEC 463 def_bool y 464 select KEXEC_CORE 465 466config KEXEC_FILE 467 bool "kexec file based system call" 468 select KEXEC_CORE 469 select BUILD_BIN2C 470 depends on CRYPTO 471 depends on CRYPTO_SHA256 472 depends on CRYPTO_SHA256_S390 473 help 474 Enable the kexec file based system call. In contrast to the normal 475 kexec system call this system call takes file descriptors for the 476 kernel and initramfs as arguments. 477 478config ARCH_HAS_KEXEC_PURGATORY 479 def_bool y 480 depends on KEXEC_FILE 481 482config KEXEC_SIG 483 bool "Verify kernel signature during kexec_file_load() syscall" 484 depends on KEXEC_FILE && MODULE_SIG_FORMAT 485 help 486 This option makes kernel signature verification mandatory for 487 the kexec_file_load() syscall. 488 489 In addition to that option, you need to enable signature 490 verification for the corresponding kernel image type being 491 loaded in order for this to work. 492 493config ARCH_RANDOM 494 def_bool y 495 prompt "s390 architectural random number generation API" 496 help 497 Enable the s390 architectural random number generation API 498 to provide random data for all consumers within the Linux 499 kernel. 500 501 When enabled the arch_random_* functions declared in linux/random.h 502 are implemented. The implementation is based on the s390 CPACF 503 instruction subfunction TRNG which provides a real true random 504 number generator. 505 506 If unsure, say Y. 507 508config KERNEL_NOBP 509 def_bool n 510 prompt "Enable modified branch prediction for the kernel by default" 511 help 512 If this option is selected the kernel will switch to a modified 513 branch prediction mode if the firmware interface is available. 514 The modified branch prediction mode improves the behaviour in 515 regard to speculative execution. 516 517 With the option enabled the kernel parameter "nobp=0" or "nospec" 518 can be used to run the kernel in the normal branch prediction mode. 519 520 With the option disabled the modified branch prediction mode is 521 enabled with the "nobp=1" kernel parameter. 522 523 If unsure, say N. 524 525config EXPOLINE 526 def_bool n 527 depends on $(cc-option,-mindirect-branch=thunk) 528 prompt "Avoid speculative indirect branches in the kernel" 529 help 530 Compile the kernel with the expoline compiler options to guard 531 against kernel-to-user data leaks by avoiding speculative indirect 532 branches. 533 Requires a compiler with -mindirect-branch=thunk support for full 534 protection. The kernel may run slower. 535 536 If unsure, say N. 537 538config EXPOLINE_EXTERN 539 def_bool n 540 depends on EXPOLINE 541 depends on CC_IS_GCC && GCC_VERSION >= 110200 542 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 543 prompt "Generate expolines as extern functions." 544 help 545 This option is required for some tooling like kpatch. The kernel is 546 compiled with -mindirect-branch=thunk-extern and requires a newer 547 compiler. 548 549 If unsure, say N. 550 551choice 552 prompt "Expoline default" 553 depends on EXPOLINE 554 default EXPOLINE_FULL 555 556config EXPOLINE_OFF 557 bool "spectre_v2=off" 558 559config EXPOLINE_AUTO 560 bool "spectre_v2=auto" 561 562config EXPOLINE_FULL 563 bool "spectre_v2=on" 564 565endchoice 566 567config RELOCATABLE 568 bool "Build a relocatable kernel" 569 select MODULE_REL_CRCS if MODVERSIONS 570 default y 571 help 572 This builds a kernel image that retains relocation information 573 so it can be loaded at an arbitrary address. 574 The kernel is linked as a position-independent executable (PIE) 575 and contains dynamic relocations which are processed early in the 576 bootup process. 577 The relocations make the kernel image about 15% larger (compressed 578 10%), but are discarded at runtime. 579 580config RANDOMIZE_BASE 581 bool "Randomize the address of the kernel image (KASLR)" 582 depends on RELOCATABLE 583 default y 584 help 585 In support of Kernel Address Space Layout Randomization (KASLR), 586 this randomizes the address at which the kernel image is loaded, 587 as a security feature that deters exploit attempts relying on 588 knowledge of the location of kernel internals. 589 590endmenu 591 592menu "Memory setup" 593 594config ARCH_SPARSEMEM_ENABLE 595 def_bool y 596 select SPARSEMEM_VMEMMAP_ENABLE 597 select SPARSEMEM_VMEMMAP 598 599config ARCH_SPARSEMEM_DEFAULT 600 def_bool y 601 602config MAX_PHYSMEM_BITS 603 int "Maximum size of supported physical memory in bits (42-53)" 604 range 42 53 605 default "46" 606 help 607 This option specifies the maximum supported size of physical memory 608 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 609 Increasing the number of bits also increases the kernel image size. 610 By default 46 bits (64TB) are supported. 611 612config CHECK_STACK 613 def_bool y 614 depends on !VMAP_STACK 615 prompt "Detect kernel stack overflow" 616 help 617 This option enables the compiler option -mstack-guard and 618 -mstack-size if they are available. If the compiler supports them 619 it will emit additional code to each function prolog to trigger 620 an illegal operation if the kernel stack is about to overflow. 621 622 Say N if you are unsure. 623 624config STACK_GUARD 625 int "Size of the guard area (128-1024)" 626 range 128 1024 627 depends on CHECK_STACK 628 default "256" 629 help 630 This allows you to specify the size of the guard area at the lower 631 end of the kernel stack. If the kernel stack points into the guard 632 area on function entry an illegal operation is triggered. The size 633 needs to be a power of 2. Please keep in mind that the size of an 634 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 635 The minimum size for the stack guard should be 256 for 31 bit and 636 512 for 64 bit. 637 638endmenu 639 640menu "I/O subsystem" 641 642config QDIO 643 def_tristate y 644 prompt "QDIO support" 645 help 646 This driver provides the Queued Direct I/O base support for 647 IBM System z. 648 649 To compile this driver as a module, choose M here: the 650 module will be called qdio. 651 652 If unsure, say Y. 653 654if PCI 655 656config PCI_NR_FUNCTIONS 657 int "Maximum number of PCI functions (1-4096)" 658 range 1 4096 659 default "512" 660 help 661 This allows you to specify the maximum number of PCI functions which 662 this kernel will support. 663 664endif # PCI 665 666config HAS_IOMEM 667 def_bool PCI 668 669config CHSC_SCH 670 def_tristate m 671 prompt "Support for CHSC subchannels" 672 help 673 This driver allows usage of CHSC subchannels. A CHSC subchannel 674 is usually present on LPAR only. 675 The driver creates a device /dev/chsc, which may be used to 676 obtain I/O configuration information about the machine and 677 to issue asynchronous chsc commands (DANGEROUS). 678 You will usually only want to use this interface on a special 679 LPAR designated for system management. 680 681 To compile this driver as a module, choose M here: the 682 module will be called chsc_sch. 683 684 If unsure, say N. 685 686config SCM_BUS 687 def_bool y 688 prompt "SCM bus driver" 689 help 690 Bus driver for Storage Class Memory. 691 692config EADM_SCH 693 def_tristate m 694 prompt "Support for EADM subchannels" 695 depends on SCM_BUS 696 help 697 This driver allows usage of EADM subchannels. EADM subchannels act 698 as a communication vehicle for SCM increments. 699 700 To compile this driver as a module, choose M here: the 701 module will be called eadm_sch. 702 703config VFIO_CCW 704 def_tristate n 705 prompt "Support for VFIO-CCW subchannels" 706 depends on S390_CCW_IOMMU && VFIO_MDEV 707 help 708 This driver allows usage of I/O subchannels via VFIO-CCW. 709 710 To compile this driver as a module, choose M here: the 711 module will be called vfio_ccw. 712 713config VFIO_AP 714 def_tristate n 715 prompt "VFIO support for AP devices" 716 depends on S390_AP_IOMMU && VFIO_MDEV && KVM 717 depends on ZCRYPT 718 help 719 This driver grants access to Adjunct Processor (AP) devices 720 via the VFIO mediated device interface. 721 722 To compile this driver as a module, choose M here: the module 723 will be called vfio_ap. 724 725endmenu 726 727menu "Dump support" 728 729config CRASH_DUMP 730 bool "kernel crash dumps" 731 select KEXEC 732 help 733 Generate crash dump after being started by kexec. 734 Crash dump kernels are loaded in the main kernel with kexec-tools 735 into a specially reserved region and then later executed after 736 a crash by kdump/kexec. 737 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 738 This option also enables s390 zfcpdump. 739 See also <file:Documentation/s390/zfcpdump.rst> 740 741endmenu 742 743config CCW 744 def_bool y 745 746config HAVE_PNETID 747 tristate 748 default (SMC || CCWGROUP) 749 750menu "Virtualization" 751 752config PROTECTED_VIRTUALIZATION_GUEST 753 def_bool n 754 prompt "Protected virtualization guest support" 755 select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS 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