1# SPDX-License-Identifier: GPL-2.0 2config MMU 3 def_bool y 4 5config CPU_BIG_ENDIAN 6 def_bool y 7 8config LOCKDEP_SUPPORT 9 def_bool y 10 11config STACKTRACE_SUPPORT 12 def_bool y 13 14config ARCH_HAS_ILOG2_U32 15 def_bool n 16 17config ARCH_HAS_ILOG2_U64 18 def_bool n 19 20config GENERIC_HWEIGHT 21 def_bool y 22 23config GENERIC_BUG 24 def_bool y if BUG 25 26config GENERIC_BUG_RELATIVE_POINTERS 27 def_bool y 28 29config GENERIC_LOCKBREAK 30 def_bool y if PREEMPTION 31 32config PGSTE 33 def_bool y if KVM 34 35config AUDIT_ARCH 36 def_bool y 37 38config NO_IOPORT_MAP 39 def_bool y 40 41config PCI_QUIRKS 42 def_bool n 43 44config ARCH_SUPPORTS_UPROBES 45 def_bool y 46 47config KASAN_SHADOW_OFFSET 48 hex 49 depends on KASAN 50 default 0x1C000000000000 51 52config S390 53 def_bool y 54 # 55 # Note: keep this list sorted alphabetically 56 # 57 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 58 select ALTERNATE_USER_ADDRESS_SPACE 59 select ARCH_32BIT_USTAT_F_TINODE 60 select ARCH_BINFMT_ELF_STATE 61 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 62 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM 63 select ARCH_ENABLE_MEMORY_HOTREMOVE 64 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 65 select ARCH_HAS_CURRENT_STACK_POINTER 66 select ARCH_HAS_DEBUG_VM_PGTABLE 67 select ARCH_HAS_DEBUG_WX 68 select ARCH_HAS_DEVMEM_IS_ALLOWED 69 select ARCH_HAS_ELF_RANDOMIZE 70 select ARCH_HAS_FORCE_DMA_UNENCRYPTED 71 select ARCH_HAS_FORTIFY_SOURCE 72 select ARCH_HAS_GCOV_PROFILE_ALL 73 select ARCH_HAS_GIGANTIC_PAGE 74 select ARCH_HAS_KCOV 75 select ARCH_HAS_MEMBARRIER_SYNC_CORE 76 select ARCH_HAS_MEM_ENCRYPT 77 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 78 select ARCH_HAS_PTE_SPECIAL 79 select ARCH_HAS_SCALED_CPUTIME 80 select ARCH_HAS_SET_DIRECT_MAP 81 select ARCH_HAS_SET_MEMORY 82 select ARCH_HAS_STRICT_KERNEL_RWX 83 select ARCH_HAS_STRICT_MODULE_RWX 84 select ARCH_HAS_SYSCALL_WRAPPER 85 select ARCH_HAS_UBSAN_SANITIZE_ALL 86 select ARCH_HAS_VDSO_DATA 87 select ARCH_HAVE_NMI_SAFE_CMPXCHG 88 select ARCH_INLINE_READ_LOCK 89 select ARCH_INLINE_READ_LOCK_BH 90 select ARCH_INLINE_READ_LOCK_IRQ 91 select ARCH_INLINE_READ_LOCK_IRQSAVE 92 select ARCH_INLINE_READ_TRYLOCK 93 select ARCH_INLINE_READ_UNLOCK 94 select ARCH_INLINE_READ_UNLOCK_BH 95 select ARCH_INLINE_READ_UNLOCK_IRQ 96 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE 97 select ARCH_INLINE_SPIN_LOCK 98 select ARCH_INLINE_SPIN_LOCK_BH 99 select ARCH_INLINE_SPIN_LOCK_IRQ 100 select ARCH_INLINE_SPIN_LOCK_IRQSAVE 101 select ARCH_INLINE_SPIN_TRYLOCK 102 select ARCH_INLINE_SPIN_TRYLOCK_BH 103 select ARCH_INLINE_SPIN_UNLOCK 104 select ARCH_INLINE_SPIN_UNLOCK_BH 105 select ARCH_INLINE_SPIN_UNLOCK_IRQ 106 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE 107 select ARCH_INLINE_WRITE_LOCK 108 select ARCH_INLINE_WRITE_LOCK_BH 109 select ARCH_INLINE_WRITE_LOCK_IRQ 110 select ARCH_INLINE_WRITE_LOCK_IRQSAVE 111 select ARCH_INLINE_WRITE_TRYLOCK 112 select ARCH_INLINE_WRITE_UNLOCK 113 select ARCH_INLINE_WRITE_UNLOCK_BH 114 select ARCH_INLINE_WRITE_UNLOCK_IRQ 115 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE 116 select ARCH_STACKWALK 117 select ARCH_SUPPORTS_ATOMIC_RMW 118 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 119 select ARCH_SUPPORTS_HUGETLBFS 120 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG 121 select ARCH_SUPPORTS_NUMA_BALANCING 122 select ARCH_SUPPORTS_PER_VMA_LOCK 123 select ARCH_USE_BUILTIN_BSWAP 124 select ARCH_USE_CMPXCHG_LOCKREF 125 select ARCH_USE_SYM_ANNOTATIONS 126 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 127 select ARCH_WANTS_NO_INSTR 128 select ARCH_WANT_DEFAULT_BPF_JIT 129 select ARCH_WANT_IPC_PARSE_VERSION 130 select ARCH_WANT_OPTIMIZE_VMEMMAP 131 select BUILDTIME_TABLE_SORT 132 select CLONE_BACKWARDS2 133 select DMA_OPS if PCI 134 select DYNAMIC_FTRACE if FUNCTION_TRACER 135 select FUNCTION_ALIGNMENT_8B if CC_IS_GCC 136 select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC 137 select GENERIC_ALLOCATOR 138 select GENERIC_CPU_AUTOPROBE 139 select GENERIC_CPU_VULNERABILITIES 140 select GENERIC_ENTRY 141 select GENERIC_GETTIMEOFDAY 142 select GENERIC_PTDUMP 143 select GENERIC_SMP_IDLE_THREAD 144 select GENERIC_TIME_VSYSCALL 145 select GENERIC_VDSO_TIME_NS 146 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 147 select HAVE_ARCH_AUDITSYSCALL 148 select HAVE_ARCH_JUMP_LABEL 149 select HAVE_ARCH_JUMP_LABEL_RELATIVE 150 select HAVE_ARCH_KASAN 151 select HAVE_ARCH_KASAN_VMALLOC 152 select HAVE_ARCH_KCSAN 153 select HAVE_ARCH_KFENCE 154 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 155 select HAVE_ARCH_SECCOMP_FILTER 156 select HAVE_ARCH_SOFT_DIRTY 157 select HAVE_ARCH_STACKLEAK 158 select HAVE_ARCH_TRACEHOOK 159 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 160 select HAVE_ARCH_VMAP_STACK 161 select HAVE_ASM_MODVERSIONS 162 select HAVE_CMPXCHG_DOUBLE 163 select HAVE_CMPXCHG_LOCAL 164 select HAVE_DEBUG_KMEMLEAK 165 select HAVE_DMA_CONTIGUOUS 166 select HAVE_DYNAMIC_FTRACE 167 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 168 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 169 select HAVE_DYNAMIC_FTRACE_WITH_REGS 170 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 171 select HAVE_EFFICIENT_UNALIGNED_ACCESS 172 select HAVE_FAST_GUP 173 select HAVE_FENTRY 174 select HAVE_FTRACE_MCOUNT_RECORD 175 select HAVE_FUNCTION_ARG_ACCESS_API 176 select HAVE_FUNCTION_ERROR_INJECTION 177 select HAVE_FUNCTION_GRAPH_TRACER 178 select HAVE_FUNCTION_TRACER 179 select HAVE_GCC_PLUGINS 180 select HAVE_GENERIC_VDSO 181 select HAVE_IOREMAP_PROT if PCI 182 select HAVE_KERNEL_BZIP2 183 select HAVE_KERNEL_GZIP 184 select HAVE_KERNEL_LZ4 185 select HAVE_KERNEL_LZMA 186 select HAVE_KERNEL_LZO 187 select HAVE_KERNEL_UNCOMPRESSED 188 select HAVE_KERNEL_XZ 189 select HAVE_KERNEL_ZSTD 190 select HAVE_KPROBES 191 select HAVE_KPROBES_ON_FTRACE 192 select HAVE_KRETPROBES 193 select HAVE_KVM 194 select HAVE_LIVEPATCH 195 select HAVE_MEMBLOCK_PHYS_MAP 196 select HAVE_MOD_ARCH_SPECIFIC 197 select HAVE_NMI 198 select HAVE_NOP_MCOUNT 199 select HAVE_PCI 200 select HAVE_PERF_EVENTS 201 select HAVE_PERF_REGS 202 select HAVE_PERF_USER_STACK_DUMP 203 select HAVE_REGS_AND_STACK_ACCESS_API 204 select HAVE_RELIABLE_STACKTRACE 205 select HAVE_RETHOOK 206 select HAVE_RSEQ 207 select HAVE_SAMPLE_FTRACE_DIRECT 208 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 209 select HAVE_SETUP_PER_CPU_AREA 210 select HAVE_SOFTIRQ_ON_OWN_STACK 211 select HAVE_SYSCALL_TRACEPOINTS 212 select HAVE_VIRT_CPU_ACCOUNTING 213 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 214 select IOMMU_HELPER if PCI 215 select IOMMU_SUPPORT if PCI 216 select MMU_GATHER_MERGE_VMAS 217 select MMU_GATHER_NO_GATHER 218 select MMU_GATHER_RCU_TABLE_FREE 219 select MODULES_USE_ELF_RELA 220 select NEED_DMA_MAP_STATE if PCI 221 select NEED_PER_CPU_EMBED_FIRST_CHUNK 222 select NEED_SG_DMA_LENGTH if PCI 223 select OLD_SIGACTION 224 select OLD_SIGSUSPEND3 225 select PCI_DOMAINS if PCI 226 select PCI_MSI if PCI 227 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 228 select SPARSE_IRQ 229 select SWIOTLB 230 select SYSCTL_EXCEPTION_TRACE 231 select THREAD_INFO_IN_TASK 232 select TRACE_IRQFLAGS_SUPPORT 233 select TTY 234 select VIRT_CPU_ACCOUNTING 235 select ZONE_DMA 236 # Note: keep the above list sorted alphabetically 237 238config SCHED_OMIT_FRAME_POINTER 239 def_bool y 240 241config PGTABLE_LEVELS 242 int 243 default 5 244 245source "kernel/livepatch/Kconfig" 246 247menu "Processor type and features" 248 249config HAVE_MARCH_Z10_FEATURES 250 def_bool n 251 252config HAVE_MARCH_Z196_FEATURES 253 def_bool n 254 select HAVE_MARCH_Z10_FEATURES 255 256config HAVE_MARCH_ZEC12_FEATURES 257 def_bool n 258 select HAVE_MARCH_Z196_FEATURES 259 260config HAVE_MARCH_Z13_FEATURES 261 def_bool n 262 select HAVE_MARCH_ZEC12_FEATURES 263 264config HAVE_MARCH_Z14_FEATURES 265 def_bool n 266 select HAVE_MARCH_Z13_FEATURES 267 268config HAVE_MARCH_Z15_FEATURES 269 def_bool n 270 select HAVE_MARCH_Z14_FEATURES 271 272config HAVE_MARCH_Z16_FEATURES 273 def_bool n 274 select HAVE_MARCH_Z15_FEATURES 275 276choice 277 prompt "Processor type" 278 default MARCH_Z196 279 280config MARCH_Z10 281 bool "IBM System z10" 282 select HAVE_MARCH_Z10_FEATURES 283 depends on $(cc-option,-march=z10) 284 help 285 Select this to enable optimizations for IBM System z10 (2097 and 2098 286 series). This is the oldest machine generation currently supported. 287 288config MARCH_Z196 289 bool "IBM zEnterprise 114 and 196" 290 select HAVE_MARCH_Z196_FEATURES 291 depends on $(cc-option,-march=z196) 292 help 293 Select this to enable optimizations for IBM zEnterprise 114 and 196 294 (2818 and 2817 series). The kernel will be slightly faster but will 295 not work on older machines. 296 297config MARCH_ZEC12 298 bool "IBM zBC12 and zEC12" 299 select HAVE_MARCH_ZEC12_FEATURES 300 depends on $(cc-option,-march=zEC12) 301 help 302 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 303 2827 series). The kernel will be slightly faster but will not work on 304 older machines. 305 306config MARCH_Z13 307 bool "IBM z13s and z13" 308 select HAVE_MARCH_Z13_FEATURES 309 depends on $(cc-option,-march=z13) 310 help 311 Select this to enable optimizations for IBM z13s and z13 (2965 and 312 2964 series). The kernel will be slightly faster but will not work on 313 older machines. 314 315config MARCH_Z14 316 bool "IBM z14 ZR1 and z14" 317 select HAVE_MARCH_Z14_FEATURES 318 depends on $(cc-option,-march=z14) 319 help 320 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 321 and 3906 series). The kernel will be slightly faster but will not 322 work on older machines. 323 324config MARCH_Z15 325 bool "IBM z15" 326 select HAVE_MARCH_Z15_FEATURES 327 depends on $(cc-option,-march=z15) 328 help 329 Select this to enable optimizations for IBM z15 (8562 330 and 8561 series). The kernel will be slightly faster but will not 331 work on older machines. 332 333config MARCH_Z16 334 bool "IBM z16" 335 select HAVE_MARCH_Z16_FEATURES 336 depends on $(cc-option,-march=z16) 337 help 338 Select this to enable optimizations for IBM z16 (3931 and 339 3932 series). 340 341endchoice 342 343config MARCH_Z10_TUNE 344 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 345 346config MARCH_Z196_TUNE 347 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 348 349config MARCH_ZEC12_TUNE 350 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 351 352config MARCH_Z13_TUNE 353 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 354 355config MARCH_Z14_TUNE 356 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 357 358config MARCH_Z15_TUNE 359 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 360 361config MARCH_Z16_TUNE 362 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 363 364choice 365 prompt "Tune code generation" 366 default TUNE_DEFAULT 367 help 368 Cause the compiler to tune (-mtune) the generated code for a machine. 369 This will make the code run faster on the selected machine but 370 somewhat slower on other machines. 371 This option only changes how the compiler emits instructions, not the 372 selection of instructions itself, so the resulting kernel will run on 373 all other machines. 374 375config TUNE_DEFAULT 376 bool "Default" 377 help 378 Tune the generated code for the target processor for which the kernel 379 will be compiled. 380 381config TUNE_Z10 382 bool "IBM System z10" 383 384config TUNE_Z196 385 bool "IBM zEnterprise 114 and 196" 386 depends on $(cc-option,-mtune=z196) 387 388config TUNE_ZEC12 389 bool "IBM zBC12 and zEC12" 390 depends on $(cc-option,-mtune=zEC12) 391 392config TUNE_Z13 393 bool "IBM z13s and z13" 394 depends on $(cc-option,-mtune=z13) 395 396config TUNE_Z14 397 bool "IBM z14 ZR1 and z14" 398 depends on $(cc-option,-mtune=z14) 399 400config TUNE_Z15 401 bool "IBM z15" 402 depends on $(cc-option,-mtune=z15) 403 404config TUNE_Z16 405 bool "IBM z16" 406 depends on $(cc-option,-mtune=z16) 407 408endchoice 409 410config 64BIT 411 def_bool y 412 413config COMMAND_LINE_SIZE 414 int "Maximum size of kernel command line" 415 default 4096 416 range 896 1048576 417 help 418 This allows you to specify the maximum length of the kernel command 419 line. 420 421config COMPAT 422 def_bool y 423 prompt "Kernel support for 31 bit emulation" 424 select ARCH_WANT_OLD_COMPAT_IPC 425 select COMPAT_OLD_SIGACTION 426 select HAVE_UID16 427 depends on MULTIUSER 428 depends on !CC_IS_CLANG 429 help 430 Select this option if you want to enable your system kernel to 431 handle system-calls from ELF binaries for 31 bit ESA. This option 432 (and some other stuff like libraries and such) is needed for 433 executing 31 bit applications. It is safe to say "Y". 434 435config SMP 436 def_bool y 437 438config NR_CPUS 439 int "Maximum number of CPUs (2-512)" 440 range 2 512 441 default "64" 442 help 443 This allows you to specify the maximum number of CPUs which this 444 kernel will support. The maximum supported value is 512 and the 445 minimum value which makes sense is 2. 446 447 This is purely to save memory - each supported CPU adds 448 approximately sixteen kilobytes to the kernel image. 449 450config HOTPLUG_CPU 451 def_bool y 452 453config NUMA 454 bool "NUMA support" 455 depends on SCHED_TOPOLOGY 456 default n 457 help 458 Enable NUMA support 459 460 This option adds NUMA support to the kernel. 461 462config NODES_SHIFT 463 int 464 depends on NUMA 465 default "1" 466 467config SCHED_SMT 468 def_bool n 469 470config SCHED_MC 471 def_bool n 472 473config SCHED_TOPOLOGY 474 def_bool y 475 prompt "Topology scheduler support" 476 select SCHED_SMT 477 select SCHED_MC 478 help 479 Topology scheduler support improves the CPU scheduler's decision 480 making when dealing with machines that have multi-threading, 481 multiple cores or multiple books. 482 483source "kernel/Kconfig.hz" 484 485config KEXEC 486 def_bool y 487 select KEXEC_CORE 488 489config KEXEC_FILE 490 bool "kexec file based system call" 491 select KEXEC_CORE 492 depends on CRYPTO 493 depends on CRYPTO_SHA256 494 depends on CRYPTO_SHA256_S390 495 help 496 Enable the kexec file based system call. In contrast to the normal 497 kexec system call this system call takes file descriptors for the 498 kernel and initramfs as arguments. 499 500config ARCH_HAS_KEXEC_PURGATORY 501 def_bool y 502 depends on KEXEC_FILE 503 504config KEXEC_SIG 505 bool "Verify kernel signature during kexec_file_load() syscall" 506 depends on KEXEC_FILE && MODULE_SIG_FORMAT 507 help 508 This option makes kernel signature verification mandatory for 509 the kexec_file_load() syscall. 510 511 In addition to that option, you need to enable signature 512 verification for the corresponding kernel image type being 513 loaded in order for this to work. 514 515config KERNEL_NOBP 516 def_bool n 517 prompt "Enable modified branch prediction for the kernel by default" 518 help 519 If this option is selected the kernel will switch to a modified 520 branch prediction mode if the firmware interface is available. 521 The modified branch prediction mode improves the behaviour in 522 regard to speculative execution. 523 524 With the option enabled the kernel parameter "nobp=0" or "nospec" 525 can be used to run the kernel in the normal branch prediction mode. 526 527 With the option disabled the modified branch prediction mode is 528 enabled with the "nobp=1" kernel parameter. 529 530 If unsure, say N. 531 532config EXPOLINE 533 def_bool n 534 depends on $(cc-option,-mindirect-branch=thunk) 535 prompt "Avoid speculative indirect branches in the kernel" 536 help 537 Compile the kernel with the expoline compiler options to guard 538 against kernel-to-user data leaks by avoiding speculative indirect 539 branches. 540 Requires a compiler with -mindirect-branch=thunk support for full 541 protection. The kernel may run slower. 542 543 If unsure, say N. 544 545config EXPOLINE_EXTERN 546 def_bool n 547 depends on EXPOLINE 548 depends on CC_IS_GCC && GCC_VERSION >= 110200 549 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 550 prompt "Generate expolines as extern functions." 551 help 552 This option is required for some tooling like kpatch. The kernel is 553 compiled with -mindirect-branch=thunk-extern and requires a newer 554 compiler. 555 556 If unsure, say N. 557 558choice 559 prompt "Expoline default" 560 depends on EXPOLINE 561 default EXPOLINE_FULL 562 563config EXPOLINE_OFF 564 bool "spectre_v2=off" 565 566config EXPOLINE_AUTO 567 bool "spectre_v2=auto" 568 569config EXPOLINE_FULL 570 bool "spectre_v2=on" 571 572endchoice 573 574config RELOCATABLE 575 def_bool y 576 help 577 This builds a kernel image that retains relocation information 578 so it can be loaded at an arbitrary address. 579 The kernel is linked as a position-independent executable (PIE) 580 and contains dynamic relocations which are processed early in the 581 bootup process. 582 The relocations make the kernel image about 15% larger (compressed 583 10%), but are discarded at runtime. 584 Note: this option exists only for documentation purposes, please do 585 not remove it. 586 587config RANDOMIZE_BASE 588 bool "Randomize the address of the kernel image (KASLR)" 589 default y 590 help 591 In support of Kernel Address Space Layout Randomization (KASLR), 592 this randomizes the address at which the kernel image is loaded, 593 as a security feature that deters exploit attempts relying on 594 knowledge of the location of kernel internals. 595 596endmenu 597 598menu "Memory setup" 599 600config ARCH_SPARSEMEM_ENABLE 601 def_bool y 602 select SPARSEMEM_VMEMMAP_ENABLE 603 select SPARSEMEM_VMEMMAP 604 605config ARCH_SPARSEMEM_DEFAULT 606 def_bool y 607 608config MAX_PHYSMEM_BITS 609 int "Maximum size of supported physical memory in bits (42-53)" 610 range 42 53 611 default "46" 612 help 613 This option specifies the maximum supported size of physical memory 614 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 615 Increasing the number of bits also increases the kernel image size. 616 By default 46 bits (64TB) are supported. 617 618config CHECK_STACK 619 def_bool y 620 depends on !VMAP_STACK 621 prompt "Detect kernel stack overflow" 622 help 623 This option enables the compiler option -mstack-guard and 624 -mstack-size if they are available. If the compiler supports them 625 it will emit additional code to each function prolog to trigger 626 an illegal operation if the kernel stack is about to overflow. 627 628 Say N if you are unsure. 629 630config STACK_GUARD 631 int "Size of the guard area (128-1024)" 632 range 128 1024 633 depends on CHECK_STACK 634 default "256" 635 help 636 This allows you to specify the size of the guard area at the lower 637 end of the kernel stack. If the kernel stack points into the guard 638 area on function entry an illegal operation is triggered. The size 639 needs to be a power of 2. Please keep in mind that the size of an 640 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 641 The minimum size for the stack guard should be 256 for 31 bit and 642 512 for 64 bit. 643 644endmenu 645 646menu "I/O subsystem" 647 648config QDIO 649 def_tristate y 650 prompt "QDIO support" 651 help 652 This driver provides the Queued Direct I/O base support for 653 IBM System z. 654 655 To compile this driver as a module, choose M here: the 656 module will be called qdio. 657 658 If unsure, say Y. 659 660if PCI 661 662config PCI_NR_FUNCTIONS 663 int "Maximum number of PCI functions (1-4096)" 664 range 1 4096 665 default "512" 666 help 667 This allows you to specify the maximum number of PCI functions which 668 this kernel will support. 669 670endif # PCI 671 672config HAS_IOMEM 673 def_bool PCI 674 675config CHSC_SCH 676 def_tristate m 677 prompt "Support for CHSC subchannels" 678 help 679 This driver allows usage of CHSC subchannels. A CHSC subchannel 680 is usually present on LPAR only. 681 The driver creates a device /dev/chsc, which may be used to 682 obtain I/O configuration information about the machine and 683 to issue asynchronous chsc commands (DANGEROUS). 684 You will usually only want to use this interface on a special 685 LPAR designated for system management. 686 687 To compile this driver as a module, choose M here: the 688 module will be called chsc_sch. 689 690 If unsure, say N. 691 692config SCM_BUS 693 def_bool y 694 prompt "SCM bus driver" 695 help 696 Bus driver for Storage Class Memory. 697 698config EADM_SCH 699 def_tristate m 700 prompt "Support for EADM subchannels" 701 depends on SCM_BUS 702 help 703 This driver allows usage of EADM subchannels. EADM subchannels act 704 as a communication vehicle for SCM increments. 705 706 To compile this driver as a module, choose M here: the 707 module will be called eadm_sch. 708 709config VFIO_CCW 710 def_tristate n 711 prompt "Support for VFIO-CCW subchannels" 712 depends on VFIO 713 select VFIO_MDEV 714 help 715 This driver allows usage of I/O subchannels via VFIO-CCW. 716 717 To compile this driver as a module, choose M here: the 718 module will be called vfio_ccw. 719 720config VFIO_AP 721 def_tristate n 722 prompt "VFIO support for AP devices" 723 depends on KVM 724 depends on VFIO 725 depends on ZCRYPT 726 select VFIO_MDEV 727 help 728 This driver grants access to Adjunct Processor (AP) devices 729 via the VFIO mediated device interface. 730 731 To compile this driver as a module, choose M here: the module 732 will be called vfio_ap. 733 734endmenu 735 736menu "Dump support" 737 738config CRASH_DUMP 739 bool "kernel crash dumps" 740 select KEXEC 741 help 742 Generate crash dump after being started by kexec. 743 Crash dump kernels are loaded in the main kernel with kexec-tools 744 into a specially reserved region and then later executed after 745 a crash by kdump/kexec. 746 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 747 This option also enables s390 zfcpdump. 748 See also <file:Documentation/s390/zfcpdump.rst> 749 750endmenu 751 752config CCW 753 def_bool y 754 755config HAVE_PNETID 756 tristate 757 default (SMC || CCWGROUP) 758 759menu "Virtualization" 760 761config PROTECTED_VIRTUALIZATION_GUEST 762 def_bool n 763 prompt "Protected virtualization guest support" 764 help 765 Select this option, if you want to be able to run this 766 kernel as a protected virtualization KVM guest. 767 Protected virtualization capable machines have a mini hypervisor 768 located at machine level (an ultravisor). With help of the 769 Ultravisor, KVM will be able to run "protected" VMs, special 770 VMs whose memory and management data are unavailable to KVM. 771 772config PFAULT 773 def_bool y 774 prompt "Pseudo page fault support" 775 help 776 Select this option, if you want to use PFAULT pseudo page fault 777 handling under VM. If running native or in LPAR, this option 778 has no effect. If your VM does not support PFAULT, PAGEEX 779 pseudo page fault handling will be used. 780 Note that VM 4.2 supports PFAULT but has a bug in its 781 implementation that causes some problems. 782 Everybody who wants to run Linux under VM != VM4.2 should select 783 this option. 784 785config CMM 786 def_tristate n 787 prompt "Cooperative memory management" 788 help 789 Select this option, if you want to enable the kernel interface 790 to reduce the memory size of the system. This is accomplished 791 by allocating pages of memory and put them "on hold". This only 792 makes sense for a system running under VM where the unused pages 793 will be reused by VM for other guest systems. The interface 794 allows an external monitor to balance memory of many systems. 795 Everybody who wants to run Linux under VM should select this 796 option. 797 798config CMM_IUCV 799 def_bool y 800 prompt "IUCV special message interface to cooperative memory management" 801 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 802 help 803 Select this option to enable the special message interface to 804 the cooperative memory management. 805 806config APPLDATA_BASE 807 def_bool n 808 prompt "Linux - VM Monitor Stream, base infrastructure" 809 depends on PROC_SYSCTL 810 help 811 This provides a kernel interface for creating and updating z/VM APPLDATA 812 monitor records. The monitor records are updated at certain time 813 intervals, once the timer is started. 814 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 815 i.e. enables or disables monitoring on the Linux side. 816 A custom interval value (in seconds) can be written to 817 /proc/appldata/interval. 818 819 Defaults are 60 seconds interval and timer off. 820 The /proc entries can also be read from, showing the current settings. 821 822config APPLDATA_MEM 823 def_tristate m 824 prompt "Monitor memory management statistics" 825 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 826 help 827 This provides memory management related data to the Linux - VM Monitor 828 Stream, like paging/swapping rate, memory utilisation, etc. 829 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 830 APPLDATA monitor record, i.e. enables or disables monitoring this record 831 on the z/VM side. 832 833 Default is disabled. 834 The /proc entry can also be read from, showing the current settings. 835 836 This can also be compiled as a module, which will be called 837 appldata_mem.o. 838 839config APPLDATA_OS 840 def_tristate m 841 prompt "Monitor OS statistics" 842 depends on APPLDATA_BASE 843 help 844 This provides OS related data to the Linux - VM Monitor Stream, like 845 CPU utilisation, etc. 846 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 847 APPLDATA monitor record, i.e. enables or disables monitoring this record 848 on the z/VM side. 849 850 Default is disabled. 851 This can also be compiled as a module, which will be called 852 appldata_os.o. 853 854config APPLDATA_NET_SUM 855 def_tristate m 856 prompt "Monitor overall network statistics" 857 depends on APPLDATA_BASE && NET 858 help 859 This provides network related data to the Linux - VM Monitor Stream, 860 currently there is only a total sum of network I/O statistics, no 861 per-interface data. 862 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 863 APPLDATA monitor record, i.e. enables or disables monitoring this record 864 on the z/VM side. 865 866 Default is disabled. 867 This can also be compiled as a module, which will be called 868 appldata_net_sum.o. 869 870config S390_HYPFS_FS 871 def_bool y 872 prompt "s390 hypervisor file system support" 873 select SYS_HYPERVISOR 874 help 875 This is a virtual file system intended to provide accounting 876 information in an s390 hypervisor environment. 877 878source "arch/s390/kvm/Kconfig" 879 880config S390_GUEST 881 def_bool y 882 prompt "s390 support for virtio devices" 883 select TTY 884 select VIRTUALIZATION 885 select VIRTIO 886 help 887 Enabling this option adds support for virtio based paravirtual device 888 drivers on s390. 889 890 Select this option if you want to run the kernel as a guest under 891 the KVM hypervisor. 892 893endmenu 894 895config S390_MODULES_SANITY_TEST_HELPERS 896 def_bool n 897 898menu "Selftests" 899 900config S390_UNWIND_SELFTEST 901 def_tristate n 902 depends on KUNIT 903 default KUNIT_ALL_TESTS 904 prompt "Test unwind functions" 905 help 906 This option enables s390 specific stack unwinder testing kernel 907 module. This option is not useful for distributions or general 908 kernels, but only for kernel developers working on architecture code. 909 910 Say N if you are unsure. 911 912config S390_KPROBES_SANITY_TEST 913 def_tristate n 914 prompt "Enable s390 specific kprobes tests" 915 depends on KPROBES 916 depends on KUNIT 917 help 918 This option enables an s390 specific kprobes test module. This option 919 is not useful for distributions or general kernels, but only for kernel 920 developers working on architecture code. 921 922 Say N if you are unsure. 923 924config S390_MODULES_SANITY_TEST 925 def_tristate n 926 depends on KUNIT 927 default KUNIT_ALL_TESTS 928 prompt "Enable s390 specific modules tests" 929 select S390_MODULES_SANITY_TEST_HELPERS 930 help 931 This option enables an s390 specific modules test. This option is 932 not useful for distributions or general kernels, but only for 933 kernel developers working on architecture code. 934 935 Say N if you are unsure. 936endmenu 937