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 GENERIC_ALLOCATOR 129 select GENERIC_CPU_AUTOPROBE 130 select GENERIC_CPU_VULNERABILITIES 131 select GENERIC_ENTRY 132 select GENERIC_GETTIMEOFDAY 133 select GENERIC_PTDUMP 134 select GENERIC_SMP_IDLE_THREAD 135 select GENERIC_TIME_VSYSCALL 136 select GENERIC_VDSO_TIME_NS 137 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 138 select HAVE_ARCH_AUDITSYSCALL 139 select HAVE_ARCH_JUMP_LABEL 140 select HAVE_ARCH_JUMP_LABEL_RELATIVE 141 select HAVE_ARCH_KASAN 142 select HAVE_ARCH_KASAN_VMALLOC 143 select HAVE_ARCH_KCSAN 144 select HAVE_ARCH_KFENCE 145 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 146 select HAVE_ARCH_SECCOMP_FILTER 147 select HAVE_ARCH_SOFT_DIRTY 148 select HAVE_ARCH_TRACEHOOK 149 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 150 select HAVE_ARCH_VMAP_STACK 151 select HAVE_ASM_MODVERSIONS 152 select HAVE_CMPXCHG_DOUBLE 153 select HAVE_CMPXCHG_LOCAL 154 select HAVE_DEBUG_KMEMLEAK 155 select HAVE_DMA_CONTIGUOUS 156 select HAVE_DYNAMIC_FTRACE 157 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 158 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 159 select HAVE_DYNAMIC_FTRACE_WITH_REGS 160 select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES 161 select HAVE_EFFICIENT_UNALIGNED_ACCESS 162 select HAVE_FAST_GUP 163 select HAVE_FENTRY 164 select HAVE_FTRACE_MCOUNT_RECORD 165 select HAVE_FUNCTION_ARG_ACCESS_API 166 select HAVE_FUNCTION_ERROR_INJECTION 167 select HAVE_FUNCTION_GRAPH_TRACER 168 select HAVE_FUNCTION_TRACER 169 select HAVE_GCC_PLUGINS 170 select HAVE_GENERIC_VDSO 171 select HAVE_IOREMAP_PROT if PCI 172 select HAVE_KERNEL_BZIP2 173 select HAVE_KERNEL_GZIP 174 select HAVE_KERNEL_LZ4 175 select HAVE_KERNEL_LZMA 176 select HAVE_KERNEL_LZO 177 select HAVE_KERNEL_UNCOMPRESSED 178 select HAVE_KERNEL_XZ 179 select HAVE_KERNEL_ZSTD 180 select HAVE_KPROBES 181 select HAVE_KPROBES_ON_FTRACE 182 select HAVE_KRETPROBES 183 select HAVE_KVM 184 select HAVE_LIVEPATCH 185 select HAVE_MEMBLOCK_PHYS_MAP 186 select HAVE_MOD_ARCH_SPECIFIC 187 select HAVE_NMI 188 select HAVE_NOP_MCOUNT 189 select HAVE_PCI 190 select HAVE_PERF_EVENTS 191 select HAVE_PERF_REGS 192 select HAVE_PERF_USER_STACK_DUMP 193 select HAVE_REGS_AND_STACK_ACCESS_API 194 select HAVE_RELIABLE_STACKTRACE 195 select HAVE_RSEQ 196 select HAVE_SAMPLE_FTRACE_DIRECT 197 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 198 select HAVE_SOFTIRQ_ON_OWN_STACK 199 select HAVE_SYSCALL_TRACEPOINTS 200 select HAVE_VIRT_CPU_ACCOUNTING 201 select HAVE_VIRT_CPU_ACCOUNTING_IDLE 202 select IOMMU_HELPER if PCI 203 select IOMMU_SUPPORT if PCI 204 select MMU_GATHER_NO_GATHER 205 select MMU_GATHER_RCU_TABLE_FREE 206 select MODULES_USE_ELF_RELA 207 select NEED_DMA_MAP_STATE if PCI 208 select NEED_SG_DMA_LENGTH if PCI 209 select OLD_SIGACTION 210 select OLD_SIGSUSPEND3 211 select PCI_DOMAINS if PCI 212 select PCI_MSI if PCI 213 select PCI_MSI_ARCH_FALLBACKS if PCI_MSI 214 select SPARSE_IRQ 215 select SWIOTLB 216 select SYSCTL_EXCEPTION_TRACE 217 select THREAD_INFO_IN_TASK 218 select TRACE_IRQFLAGS_SUPPORT 219 select TTY 220 select VIRT_CPU_ACCOUNTING 221 select ZONE_DMA 222 # Note: keep the above list sorted alphabetically 223 224config SCHED_OMIT_FRAME_POINTER 225 def_bool y 226 227config PGTABLE_LEVELS 228 int 229 default 5 230 231source "kernel/livepatch/Kconfig" 232 233menu "Processor type and features" 234 235config HAVE_MARCH_Z10_FEATURES 236 def_bool n 237 238config HAVE_MARCH_Z196_FEATURES 239 def_bool n 240 select HAVE_MARCH_Z10_FEATURES 241 242config HAVE_MARCH_ZEC12_FEATURES 243 def_bool n 244 select HAVE_MARCH_Z196_FEATURES 245 246config HAVE_MARCH_Z13_FEATURES 247 def_bool n 248 select HAVE_MARCH_ZEC12_FEATURES 249 250config HAVE_MARCH_Z14_FEATURES 251 def_bool n 252 select HAVE_MARCH_Z13_FEATURES 253 254config HAVE_MARCH_Z15_FEATURES 255 def_bool n 256 select HAVE_MARCH_Z14_FEATURES 257 258config HAVE_MARCH_Z16_FEATURES 259 def_bool n 260 select HAVE_MARCH_Z15_FEATURES 261 262choice 263 prompt "Processor type" 264 default MARCH_Z196 265 266config MARCH_Z10 267 bool "IBM System z10" 268 select HAVE_MARCH_Z10_FEATURES 269 depends on $(cc-option,-march=z10) 270 help 271 Select this to enable optimizations for IBM System z10 (2097 and 2098 272 series). This is the oldest machine generation currently supported. 273 274config MARCH_Z196 275 bool "IBM zEnterprise 114 and 196" 276 select HAVE_MARCH_Z196_FEATURES 277 depends on $(cc-option,-march=z196) 278 help 279 Select this to enable optimizations for IBM zEnterprise 114 and 196 280 (2818 and 2817 series). The kernel will be slightly faster but will 281 not work on older machines. 282 283config MARCH_ZEC12 284 bool "IBM zBC12 and zEC12" 285 select HAVE_MARCH_ZEC12_FEATURES 286 depends on $(cc-option,-march=zEC12) 287 help 288 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and 289 2827 series). The kernel will be slightly faster but will not work on 290 older machines. 291 292config MARCH_Z13 293 bool "IBM z13s and z13" 294 select HAVE_MARCH_Z13_FEATURES 295 depends on $(cc-option,-march=z13) 296 help 297 Select this to enable optimizations for IBM z13s and z13 (2965 and 298 2964 series). The kernel will be slightly faster but will not work on 299 older machines. 300 301config MARCH_Z14 302 bool "IBM z14 ZR1 and z14" 303 select HAVE_MARCH_Z14_FEATURES 304 depends on $(cc-option,-march=z14) 305 help 306 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907 307 and 3906 series). The kernel will be slightly faster but will not 308 work on older machines. 309 310config MARCH_Z15 311 bool "IBM z15" 312 select HAVE_MARCH_Z15_FEATURES 313 depends on $(cc-option,-march=z15) 314 help 315 Select this to enable optimizations for IBM z15 (8562 316 and 8561 series). The kernel will be slightly faster but will not 317 work on older machines. 318 319config MARCH_Z16 320 bool "IBM z16" 321 select HAVE_MARCH_Z16_FEATURES 322 depends on $(cc-option,-march=z16) 323 help 324 Select this to enable optimizations for IBM z16 (3931 and 325 3932 series). 326 327endchoice 328 329config MARCH_Z10_TUNE 330 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT 331 332config MARCH_Z196_TUNE 333 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT 334 335config MARCH_ZEC12_TUNE 336 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT 337 338config MARCH_Z13_TUNE 339 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT 340 341config MARCH_Z14_TUNE 342 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT 343 344config MARCH_Z15_TUNE 345 def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT 346 347config MARCH_Z16_TUNE 348 def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT 349 350choice 351 prompt "Tune code generation" 352 default TUNE_DEFAULT 353 help 354 Cause the compiler to tune (-mtune) the generated code for a machine. 355 This will make the code run faster on the selected machine but 356 somewhat slower on other machines. 357 This option only changes how the compiler emits instructions, not the 358 selection of instructions itself, so the resulting kernel will run on 359 all other machines. 360 361config TUNE_DEFAULT 362 bool "Default" 363 help 364 Tune the generated code for the target processor for which the kernel 365 will be compiled. 366 367config TUNE_Z10 368 bool "IBM System z10" 369 370config TUNE_Z196 371 bool "IBM zEnterprise 114 and 196" 372 depends on $(cc-option,-mtune=z196) 373 374config TUNE_ZEC12 375 bool "IBM zBC12 and zEC12" 376 depends on $(cc-option,-mtune=zEC12) 377 378config TUNE_Z13 379 bool "IBM z13s and z13" 380 depends on $(cc-option,-mtune=z13) 381 382config TUNE_Z14 383 bool "IBM z14 ZR1 and z14" 384 depends on $(cc-option,-mtune=z14) 385 386config TUNE_Z15 387 bool "IBM z15" 388 depends on $(cc-option,-mtune=z15) 389 390config TUNE_Z16 391 bool "IBM z16" 392 depends on $(cc-option,-mtune=z16) 393 394endchoice 395 396config 64BIT 397 def_bool y 398 399config COMMAND_LINE_SIZE 400 int "Maximum size of kernel command line" 401 default 4096 402 range 896 1048576 403 help 404 This allows you to specify the maximum length of the kernel command 405 line. 406 407config COMPAT 408 def_bool y 409 prompt "Kernel support for 31 bit emulation" 410 select ARCH_WANT_OLD_COMPAT_IPC 411 select COMPAT_OLD_SIGACTION 412 select HAVE_UID16 413 depends on MULTIUSER 414 depends on !CC_IS_CLANG 415 help 416 Select this option if you want to enable your system kernel to 417 handle system-calls from ELF binaries for 31 bit ESA. This option 418 (and some other stuff like libraries and such) is needed for 419 executing 31 bit applications. It is safe to say "Y". 420 421config SYSVIPC_COMPAT 422 def_bool y if COMPAT && SYSVIPC 423 424config SMP 425 def_bool y 426 427config NR_CPUS 428 int "Maximum number of CPUs (2-512)" 429 range 2 512 430 default "64" 431 help 432 This allows you to specify the maximum number of CPUs which this 433 kernel will support. The maximum supported value is 512 and the 434 minimum value which makes sense is 2. 435 436 This is purely to save memory - each supported CPU adds 437 approximately sixteen kilobytes to the kernel image. 438 439config HOTPLUG_CPU 440 def_bool y 441 442config NUMA 443 bool "NUMA support" 444 depends on SCHED_TOPOLOGY 445 default n 446 help 447 Enable NUMA support 448 449 This option adds NUMA support to the kernel. 450 451config NODES_SHIFT 452 int 453 depends on NUMA 454 default "1" 455 456config SCHED_SMT 457 def_bool n 458 459config SCHED_MC 460 def_bool n 461 462config SCHED_BOOK 463 def_bool n 464 465config SCHED_DRAWER 466 def_bool n 467 468config SCHED_TOPOLOGY 469 def_bool y 470 prompt "Topology scheduler support" 471 select SCHED_SMT 472 select SCHED_MC 473 select SCHED_BOOK 474 select SCHED_DRAWER 475 help 476 Topology scheduler support improves the CPU scheduler's decision 477 making when dealing with machines that have multi-threading, 478 multiple cores or multiple books. 479 480source "kernel/Kconfig.hz" 481 482config KEXEC 483 def_bool y 484 select KEXEC_CORE 485 486config KEXEC_FILE 487 bool "kexec file based system call" 488 select KEXEC_CORE 489 select BUILD_BIN2C 490 depends on CRYPTO 491 depends on CRYPTO_SHA256 492 depends on CRYPTO_SHA256_S390 493 help 494 Enable the kexec file based system call. In contrast to the normal 495 kexec system call this system call takes file descriptors for the 496 kernel and initramfs as arguments. 497 498config ARCH_HAS_KEXEC_PURGATORY 499 def_bool y 500 depends on KEXEC_FILE 501 502config KEXEC_SIG 503 bool "Verify kernel signature during kexec_file_load() syscall" 504 depends on KEXEC_FILE && MODULE_SIG_FORMAT 505 help 506 This option makes kernel signature verification mandatory for 507 the kexec_file_load() syscall. 508 509 In addition to that option, you need to enable signature 510 verification for the corresponding kernel image type being 511 loaded in order for this to work. 512 513config ARCH_RANDOM 514 def_bool y 515 prompt "s390 architectural random number generation API" 516 help 517 Enable the s390 architectural random number generation API 518 to provide random data for all consumers within the Linux 519 kernel. 520 521 When enabled the arch_random_* functions declared in linux/random.h 522 are implemented. The implementation is based on the s390 CPACF 523 instruction subfunction TRNG which provides a real true random 524 number generator. 525 526 If unsure, say Y. 527 528config KERNEL_NOBP 529 def_bool n 530 prompt "Enable modified branch prediction for the kernel by default" 531 help 532 If this option is selected the kernel will switch to a modified 533 branch prediction mode if the firmware interface is available. 534 The modified branch prediction mode improves the behaviour in 535 regard to speculative execution. 536 537 With the option enabled the kernel parameter "nobp=0" or "nospec" 538 can be used to run the kernel in the normal branch prediction mode. 539 540 With the option disabled the modified branch prediction mode is 541 enabled with the "nobp=1" kernel parameter. 542 543 If unsure, say N. 544 545config EXPOLINE 546 def_bool n 547 depends on $(cc-option,-mindirect-branch=thunk) 548 prompt "Avoid speculative indirect branches in the kernel" 549 help 550 Compile the kernel with the expoline compiler options to guard 551 against kernel-to-user data leaks by avoiding speculative indirect 552 branches. 553 Requires a compiler with -mindirect-branch=thunk support for full 554 protection. The kernel may run slower. 555 556 If unsure, say N. 557 558config EXPOLINE_EXTERN 559 def_bool n 560 depends on EXPOLINE 561 depends on CC_IS_GCC && GCC_VERSION >= 110200 562 depends on $(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC)) 563 prompt "Generate expolines as extern functions." 564 help 565 This option is required for some tooling like kpatch. The kernel is 566 compiled with -mindirect-branch=thunk-extern and requires a newer 567 compiler. 568 569 If unsure, say N. 570 571choice 572 prompt "Expoline default" 573 depends on EXPOLINE 574 default EXPOLINE_FULL 575 576config EXPOLINE_OFF 577 bool "spectre_v2=off" 578 579config EXPOLINE_AUTO 580 bool "spectre_v2=auto" 581 582config EXPOLINE_FULL 583 bool "spectre_v2=on" 584 585endchoice 586 587config RELOCATABLE 588 bool "Build a relocatable kernel" 589 select MODULE_REL_CRCS if MODVERSIONS 590 default y 591 help 592 This builds a kernel image that retains relocation information 593 so it can be loaded at an arbitrary address. 594 The kernel is linked as a position-independent executable (PIE) 595 and contains dynamic relocations which are processed early in the 596 bootup process. 597 The relocations make the kernel image about 15% larger (compressed 598 10%), but are discarded at runtime. 599 600config RANDOMIZE_BASE 601 bool "Randomize the address of the kernel image (KASLR)" 602 depends on RELOCATABLE 603 default y 604 help 605 In support of Kernel Address Space Layout Randomization (KASLR), 606 this randomizes the address at which the kernel image is loaded, 607 as a security feature that deters exploit attempts relying on 608 knowledge of the location of kernel internals. 609 610endmenu 611 612menu "Memory setup" 613 614config ARCH_SPARSEMEM_ENABLE 615 def_bool y 616 select SPARSEMEM_VMEMMAP_ENABLE 617 select SPARSEMEM_VMEMMAP 618 619config ARCH_SPARSEMEM_DEFAULT 620 def_bool y 621 622config MAX_PHYSMEM_BITS 623 int "Maximum size of supported physical memory in bits (42-53)" 624 range 42 53 625 default "46" 626 help 627 This option specifies the maximum supported size of physical memory 628 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB). 629 Increasing the number of bits also increases the kernel image size. 630 By default 46 bits (64TB) are supported. 631 632config CHECK_STACK 633 def_bool y 634 depends on !VMAP_STACK 635 prompt "Detect kernel stack overflow" 636 help 637 This option enables the compiler option -mstack-guard and 638 -mstack-size if they are available. If the compiler supports them 639 it will emit additional code to each function prolog to trigger 640 an illegal operation if the kernel stack is about to overflow. 641 642 Say N if you are unsure. 643 644config STACK_GUARD 645 int "Size of the guard area (128-1024)" 646 range 128 1024 647 depends on CHECK_STACK 648 default "256" 649 help 650 This allows you to specify the size of the guard area at the lower 651 end of the kernel stack. If the kernel stack points into the guard 652 area on function entry an illegal operation is triggered. The size 653 needs to be a power of 2. Please keep in mind that the size of an 654 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. 655 The minimum size for the stack guard should be 256 for 31 bit and 656 512 for 64 bit. 657 658endmenu 659 660menu "I/O subsystem" 661 662config QDIO 663 def_tristate y 664 prompt "QDIO support" 665 help 666 This driver provides the Queued Direct I/O base support for 667 IBM System z. 668 669 To compile this driver as a module, choose M here: the 670 module will be called qdio. 671 672 If unsure, say Y. 673 674if PCI 675 676config PCI_NR_FUNCTIONS 677 int "Maximum number of PCI functions (1-4096)" 678 range 1 4096 679 default "512" 680 help 681 This allows you to specify the maximum number of PCI functions which 682 this kernel will support. 683 684endif # PCI 685 686config HAS_IOMEM 687 def_bool PCI 688 689config CHSC_SCH 690 def_tristate m 691 prompt "Support for CHSC subchannels" 692 help 693 This driver allows usage of CHSC subchannels. A CHSC subchannel 694 is usually present on LPAR only. 695 The driver creates a device /dev/chsc, which may be used to 696 obtain I/O configuration information about the machine and 697 to issue asynchronous chsc commands (DANGEROUS). 698 You will usually only want to use this interface on a special 699 LPAR designated for system management. 700 701 To compile this driver as a module, choose M here: the 702 module will be called chsc_sch. 703 704 If unsure, say N. 705 706config SCM_BUS 707 def_bool y 708 prompt "SCM bus driver" 709 help 710 Bus driver for Storage Class Memory. 711 712config EADM_SCH 713 def_tristate m 714 prompt "Support for EADM subchannels" 715 depends on SCM_BUS 716 help 717 This driver allows usage of EADM subchannels. EADM subchannels act 718 as a communication vehicle for SCM increments. 719 720 To compile this driver as a module, choose M here: the 721 module will be called eadm_sch. 722 723config VFIO_CCW 724 def_tristate n 725 prompt "Support for VFIO-CCW subchannels" 726 depends on S390_CCW_IOMMU && VFIO_MDEV 727 help 728 This driver allows usage of I/O subchannels via VFIO-CCW. 729 730 To compile this driver as a module, choose M here: the 731 module will be called vfio_ccw. 732 733config VFIO_AP 734 def_tristate n 735 prompt "VFIO support for AP devices" 736 depends on S390_AP_IOMMU && VFIO_MDEV && KVM 737 depends on ZCRYPT 738 help 739 This driver grants access to Adjunct Processor (AP) devices 740 via the VFIO mediated device interface. 741 742 To compile this driver as a module, choose M here: the module 743 will be called vfio_ap. 744 745endmenu 746 747menu "Dump support" 748 749config CRASH_DUMP 750 bool "kernel crash dumps" 751 select KEXEC 752 help 753 Generate crash dump after being started by kexec. 754 Crash dump kernels are loaded in the main kernel with kexec-tools 755 into a specially reserved region and then later executed after 756 a crash by kdump/kexec. 757 Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this. 758 This option also enables s390 zfcpdump. 759 See also <file:Documentation/s390/zfcpdump.rst> 760 761endmenu 762 763config CCW 764 def_bool y 765 766config HAVE_PNETID 767 tristate 768 default (SMC || CCWGROUP) 769 770menu "Virtualization" 771 772config PROTECTED_VIRTUALIZATION_GUEST 773 def_bool n 774 prompt "Protected virtualization guest support" 775 select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS 776 help 777 Select this option, if you want to be able to run this 778 kernel as a protected virtualization KVM guest. 779 Protected virtualization capable machines have a mini hypervisor 780 located at machine level (an ultravisor). With help of the 781 Ultravisor, KVM will be able to run "protected" VMs, special 782 VMs whose memory and management data are unavailable to KVM. 783 784config PFAULT 785 def_bool y 786 prompt "Pseudo page fault support" 787 help 788 Select this option, if you want to use PFAULT pseudo page fault 789 handling under VM. If running native or in LPAR, this option 790 has no effect. If your VM does not support PFAULT, PAGEEX 791 pseudo page fault handling will be used. 792 Note that VM 4.2 supports PFAULT but has a bug in its 793 implementation that causes some problems. 794 Everybody who wants to run Linux under VM != VM4.2 should select 795 this option. 796 797config CMM 798 def_tristate n 799 prompt "Cooperative memory management" 800 help 801 Select this option, if you want to enable the kernel interface 802 to reduce the memory size of the system. This is accomplished 803 by allocating pages of memory and put them "on hold". This only 804 makes sense for a system running under VM where the unused pages 805 will be reused by VM for other guest systems. The interface 806 allows an external monitor to balance memory of many systems. 807 Everybody who wants to run Linux under VM should select this 808 option. 809 810config CMM_IUCV 811 def_bool y 812 prompt "IUCV special message interface to cooperative memory management" 813 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) 814 help 815 Select this option to enable the special message interface to 816 the cooperative memory management. 817 818config APPLDATA_BASE 819 def_bool n 820 prompt "Linux - VM Monitor Stream, base infrastructure" 821 depends on PROC_SYSCTL 822 help 823 This provides a kernel interface for creating and updating z/VM APPLDATA 824 monitor records. The monitor records are updated at certain time 825 intervals, once the timer is started. 826 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, 827 i.e. enables or disables monitoring on the Linux side. 828 A custom interval value (in seconds) can be written to 829 /proc/appldata/interval. 830 831 Defaults are 60 seconds interval and timer off. 832 The /proc entries can also be read from, showing the current settings. 833 834config APPLDATA_MEM 835 def_tristate m 836 prompt "Monitor memory management statistics" 837 depends on APPLDATA_BASE && VM_EVENT_COUNTERS 838 help 839 This provides memory management related data to the Linux - VM Monitor 840 Stream, like paging/swapping rate, memory utilisation, etc. 841 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM 842 APPLDATA monitor record, i.e. enables or disables monitoring this record 843 on the z/VM side. 844 845 Default is disabled. 846 The /proc entry can also be read from, showing the current settings. 847 848 This can also be compiled as a module, which will be called 849 appldata_mem.o. 850 851config APPLDATA_OS 852 def_tristate m 853 prompt "Monitor OS statistics" 854 depends on APPLDATA_BASE 855 help 856 This provides OS related data to the Linux - VM Monitor Stream, like 857 CPU utilisation, etc. 858 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM 859 APPLDATA monitor record, i.e. enables or disables monitoring this record 860 on the z/VM side. 861 862 Default is disabled. 863 This can also be compiled as a module, which will be called 864 appldata_os.o. 865 866config APPLDATA_NET_SUM 867 def_tristate m 868 prompt "Monitor overall network statistics" 869 depends on APPLDATA_BASE && NET 870 help 871 This provides network related data to the Linux - VM Monitor Stream, 872 currently there is only a total sum of network I/O statistics, no 873 per-interface data. 874 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM 875 APPLDATA monitor record, i.e. enables or disables monitoring this record 876 on the z/VM side. 877 878 Default is disabled. 879 This can also be compiled as a module, which will be called 880 appldata_net_sum.o. 881 882config S390_HYPFS_FS 883 def_bool y 884 prompt "s390 hypervisor file system support" 885 select SYS_HYPERVISOR 886 help 887 This is a virtual file system intended to provide accounting 888 information in an s390 hypervisor environment. 889 890source "arch/s390/kvm/Kconfig" 891 892config S390_GUEST 893 def_bool y 894 prompt "s390 support for virtio devices" 895 select TTY 896 select VIRTUALIZATION 897 select VIRTIO 898 help 899 Enabling this option adds support for virtio based paravirtual device 900 drivers on s390. 901 902 Select this option if you want to run the kernel as a guest under 903 the KVM hypervisor. 904 905endmenu 906 907config S390_MODULES_SANITY_TEST_HELPERS 908 def_bool n 909 910menu "Selftests" 911 912config S390_UNWIND_SELFTEST 913 def_tristate n 914 depends on KUNIT 915 default KUNIT_ALL_TESTS 916 prompt "Test unwind functions" 917 help 918 This option enables s390 specific stack unwinder testing kernel 919 module. This option is not useful for distributions or general 920 kernels, but only for kernel developers working on architecture code. 921 922 Say N if you are unsure. 923 924config S390_KPROBES_SANITY_TEST 925 def_tristate n 926 prompt "Enable s390 specific kprobes tests" 927 depends on KPROBES 928 depends on KUNIT 929 help 930 This option enables an s390 specific kprobes test module. This option 931 is not useful for distributions or general kernels, but only for kernel 932 developers working on architecture code. 933 934 Say N if you are unsure. 935 936config S390_MODULES_SANITY_TEST 937 def_tristate n 938 depends on KUNIT 939 default KUNIT_ALL_TESTS 940 prompt "Enable s390 specific modules tests" 941 select S390_MODULES_SANITY_TEST_HELPERS 942 help 943 This option enables an s390 specific modules test. This option is 944 not useful for distributions or general kernels, but only for 945 kernel developers working on architecture code. 946 947 Say N if you are unsure. 948endmenu 949