# # For a description of the syntax of this configuration file, # see Documentation/kbuild/kconfig-language.txt. # config SCHED_MC def_bool y depends on SMP config MMU def_bool y config ZONE_DMA def_bool y depends on 64BIT config LOCKDEP_SUPPORT def_bool y config STACKTRACE_SUPPORT def_bool y config HAVE_LATENCYTOP_SUPPORT def_bool y config RWSEM_GENERIC_SPINLOCK bool config RWSEM_XCHGADD_ALGORITHM def_bool y config ARCH_HAS_ILOG2_U32 bool default n config ARCH_HAS_ILOG2_U64 bool default n config GENERIC_HWEIGHT def_bool y config GENERIC_TIME def_bool y config GENERIC_TIME_VSYSCALL def_bool y config GENERIC_CLOCKEVENTS def_bool y config GENERIC_BUG bool depends on BUG default y config NO_IOMEM def_bool y config NO_DMA def_bool y config GENERIC_LOCKBREAK bool default y depends on SMP && PREEMPT config PGSTE bool default y if KVM config VIRT_CPU_ACCOUNTING def_bool y config ARCH_SUPPORTS_DEBUG_PAGEALLOC def_bool y mainmenu "Linux Kernel Configuration" config S390 def_bool y select USE_GENERIC_SMP_HELPERS if SMP select HAVE_SYSCALL_WRAPPERS select HAVE_FUNCTION_TRACER select HAVE_FUNCTION_TRACE_MCOUNT_TEST select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FTRACE_SYSCALLS select HAVE_DYNAMIC_FTRACE select HAVE_FUNCTION_GRAPH_TRACER select HAVE_DEFAULT_NO_SPIN_MUTEXES select HAVE_OPROFILE select HAVE_KPROBES select HAVE_KRETPROBES select HAVE_KVM if 64BIT select HAVE_ARCH_TRACEHOOK select INIT_ALL_POSSIBLE source "init/Kconfig" source "kernel/Kconfig.freezer" menu "Base setup" comment "Processor type and features" source "kernel/time/Kconfig" config 64BIT bool "64 bit kernel" help Select this option if you have a 64 bit IBM zSeries machine and want to use the 64 bit addressing mode. config 32BIT bool default y if !64BIT config SMP bool "Symmetric multi-processing support" ---help--- This enables support for systems with more than one CPU. If you have a system with only one CPU, like most personal computers, say N. If you have a system with more than one CPU, say Y. If you say N here, the kernel will run on single and multiprocessor machines, but will use only one CPU of a multiprocessor machine. If you say Y here, the kernel will run on many, but not all, singleprocessor machines. On a singleprocessor machine, the kernel will run faster if you say N here. See also the SMP-HOWTO available at . Even if you don't know what to do here, say Y. config NR_CPUS int "Maximum number of CPUs (2-64)" range 2 64 depends on SMP default "32" if !64BIT default "64" if 64BIT help This allows you to specify the maximum number of CPUs which this kernel will support. The maximum supported value is 64 and the minimum value which makes sense is 2. This is purely to save memory - each supported CPU adds approximately sixteen kilobytes to the kernel image. config HOTPLUG_CPU bool "Support for hot-pluggable CPUs" depends on SMP select HOTPLUG default n help Say Y here to be able to turn CPUs off and on. CPUs can be controlled through /sys/devices/system/cpu/cpu#. Say N if you want to disable CPU hotplug. config MATHEMU bool "IEEE FPU emulation" depends on MARCH_G5 help This option is required for IEEE compliant floating point arithmetic on older S/390 machines. Say Y unless you know your machine doesn't need this. config COMPAT bool "Kernel support for 31 bit emulation" depends on 64BIT select COMPAT_BINFMT_ELF help Select this option if you want to enable your system kernel to handle system-calls from ELF binaries for 31 bit ESA. This option (and some other stuff like libraries and such) is needed for executing 31 bit applications. It is safe to say "Y". config SYSVIPC_COMPAT bool depends on COMPAT && SYSVIPC default y config AUDIT_ARCH bool default y config S390_SWITCH_AMODE bool "Switch kernel/user addressing modes" help This option allows to switch the addressing modes of kernel and user space. The kernel parameter switch_amode=on will enable this feature, default is disabled. Enabling this (via kernel parameter) on machines earlier than IBM System z9-109 EC/BC will reduce system performance. Note that this option will also be selected by selecting the execute protection option below. Enabling the execute protection via the noexec kernel parameter will also switch the addressing modes, independent of the switch_amode kernel parameter. config S390_EXEC_PROTECT bool "Data execute protection" select S390_SWITCH_AMODE help This option allows to enable a buffer overflow protection for user space programs and it also selects the addressing mode option above. The kernel parameter noexec=on will enable this feature and also switch the addressing modes, default is disabled. Enabling this (via kernel parameter) on machines earlier than IBM System z9-109 EC/BC will reduce system performance. comment "Code generation options" choice prompt "Processor type" default MARCH_G5 config MARCH_G5 bool "S/390 model G5 and G6" depends on !64BIT help Select this to build a 31 bit kernel that works on all S/390 and zSeries machines. config MARCH_Z900 bool "IBM eServer zSeries model z800 and z900" help Select this to optimize for zSeries machines. This will enable some optimizations that are not available on older 31 bit only CPUs. config MARCH_Z990 bool "IBM eServer zSeries model z890 and z990" help Select this enable optimizations for model z890/z990. This will be slightly faster but does not work on older machines such as the z900. config MARCH_Z9_109 bool "IBM System z9" help Select this to enable optimizations for IBM System z9-109, IBM System z9 Enterprise Class (z9 EC), and IBM System z9 Business Class (z9 BC). The kernel will be slightly faster but will not work on older machines such as the z990, z890, z900, and z800. config MARCH_Z10 bool "IBM System z10" help Select this to enable optimizations for IBM System z10. The kernel will be slightly faster but will not work on older machines such as the z990, z890, z900, z800, z9-109, z9-ec and z9-bc. endchoice config PACK_STACK bool "Pack kernel stack" help This option enables the compiler option -mkernel-backchain if it is available. If the option is available the compiler supports the new stack layout which dramatically reduces the minimum stack frame size. With an old compiler a non-leaf function needs a minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With -mkernel-backchain the minimum size drops to 16 byte on 31 bit and 24 byte on 64 bit. Say Y if you are unsure. config SMALL_STACK bool "Use 8kb for kernel stack instead of 16kb" depends on PACK_STACK && 64BIT && !LOCKDEP help If you say Y here and the compiler supports the -mkernel-backchain option the kernel will use a smaller kernel stack size. The reduced size is 8kb instead of 16kb. This allows to run more threads on a system and reduces the pressure on the memory management for higher order page allocations. Say N if you are unsure. config CHECK_STACK bool "Detect kernel stack overflow" help This option enables the compiler option -mstack-guard and -mstack-size if they are available. If the compiler supports them it will emit additional code to each function prolog to trigger an illegal operation if the kernel stack is about to overflow. Say N if you are unsure. config STACK_GUARD int "Size of the guard area (128-1024)" range 128 1024 depends on CHECK_STACK default "256" help This allows you to specify the size of the guard area at the lower end of the kernel stack. If the kernel stack points into the guard area on function entry an illegal operation is triggered. The size needs to be a power of 2. Please keep in mind that the size of an interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit. The minimum size for the stack guard should be 256 for 31 bit and 512 for 64 bit. config WARN_STACK bool "Emit compiler warnings for function with broken stack usage" help This option enables the compiler options -mwarn-framesize and -mwarn-dynamicstack. If the compiler supports these options it will generate warnings for function which either use alloca or create a stack frame bigger than CONFIG_WARN_STACK_SIZE. Say N if you are unsure. config WARN_STACK_SIZE int "Maximum frame size considered safe (128-2048)" range 128 2048 depends on WARN_STACK default "2048" help This allows you to specify the maximum frame size a function may have without the compiler complaining about it. config ARCH_POPULATES_NODE_MAP def_bool y comment "Kernel preemption" source "kernel/Kconfig.preempt" config ARCH_SPARSEMEM_ENABLE def_bool y select SPARSEMEM_VMEMMAP_ENABLE select SPARSEMEM_VMEMMAP select SPARSEMEM_STATIC if !64BIT config ARCH_SPARSEMEM_DEFAULT def_bool y config ARCH_SELECT_MEMORY_MODEL def_bool y config ARCH_ENABLE_MEMORY_HOTPLUG def_bool y depends on SPARSEMEM config ARCH_ENABLE_MEMORY_HOTREMOVE def_bool y config ARCH_HIBERNATION_POSSIBLE def_bool y if 64BIT source "mm/Kconfig" comment "I/O subsystem configuration" config QDIO tristate "QDIO support" ---help--- This driver provides the Queued Direct I/O base support for IBM System z. To compile this driver as a module, choose M here: the module will be called qdio. If unsure, say Y. config CHSC_SCH tristate "Support for CHSC subchannels" help This driver allows usage of CHSC subchannels. A CHSC subchannel is usually present on LPAR only. The driver creates a device /dev/chsc, which may be used to obtain I/O configuration information about the machine and to issue asynchronous chsc commands (DANGEROUS). You will usually only want to use this interface on a special LPAR designated for system management. To compile this driver as a module, choose M here: the module will be called chsc_sch. If unsure, say N. comment "Misc" config IPL bool "Builtin IPL record support" help If you want to use the produced kernel to IPL directly from a device, you have to merge a bootsector specific to the device into the first bytes of the kernel. You will have to select the IPL device. choice prompt "IPL method generated into head.S" depends on IPL default IPL_VM help Select "tape" if you want to IPL the image from a Tape. Select "vm_reader" if you are running under VM/ESA and want to IPL the image from the emulated card reader. config IPL_TAPE bool "tape" config IPL_VM bool "vm_reader" endchoice source "fs/Kconfig.binfmt" config FORCE_MAX_ZONEORDER int default "9" config PROCESS_DEBUG bool "Show crashed user process info" help Say Y to print all process fault locations to the console. This is a debugging option; you probably do not want to set it unless you are an S390 port maintainer. config PFAULT bool "Pseudo page fault support" help Select this option, if you want to use PFAULT pseudo page fault handling under VM. If running native or in LPAR, this option has no effect. If your VM does not support PFAULT, PAGEEX pseudo page fault handling will be used. Note that VM 4.2 supports PFAULT but has a bug in its implementation that causes some problems. Everybody who wants to run Linux under VM != VM4.2 should select this option. config SHARED_KERNEL bool "VM shared kernel support" help Select this option, if you want to share the text segment of the Linux kernel between different VM guests. This reduces memory usage with lots of guests but greatly increases kernel size. Also if a kernel was IPL'ed from a shared segment the kexec system call will not work. You should only select this option if you know what you are doing and want to exploit this feature. config CMM tristate "Cooperative memory management" help Select this option, if you want to enable the kernel interface to reduce the memory size of the system. This is accomplished by allocating pages of memory and put them "on hold". This only makes sense for a system running under VM where the unused pages will be reused by VM for other guest systems. The interface allows an external monitor to balance memory of many systems. Everybody who wants to run Linux under VM should select this option. config CMM_PROC bool "/proc interface to cooperative memory management" depends on CMM help Select this option to enable the /proc interface to the cooperative memory management. config CMM_IUCV bool "IUCV special message interface to cooperative memory management" depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV) help Select this option to enable the special message interface to the cooperative memory management. config PAGE_STATES bool "Unused page notification" help This enables the notification of unused pages to the hypervisor. The ESSA instruction is used to do the states changes between a page that has content and the unused state. config APPLDATA_BASE bool "Linux - VM Monitor Stream, base infrastructure" depends on PROC_FS help This provides a kernel interface for creating and updating z/VM APPLDATA monitor records. The monitor records are updated at certain time intervals, once the timer is started. Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer, i.e. enables or disables monitoring on the Linux side. A custom interval value (in seconds) can be written to /proc/appldata/interval. Defaults are 60 seconds interval and timer off. The /proc entries can also be read from, showing the current settings. config APPLDATA_MEM tristate "Monitor memory management statistics" depends on APPLDATA_BASE && VM_EVENT_COUNTERS help This provides memory management related data to the Linux - VM Monitor Stream, like paging/swapping rate, memory utilisation, etc. Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM APPLDATA monitor record, i.e. enables or disables monitoring this record on the z/VM side. Default is disabled. The /proc entry can also be read from, showing the current settings. This can also be compiled as a module, which will be called appldata_mem.o. config APPLDATA_OS tristate "Monitor OS statistics" depends on APPLDATA_BASE help This provides OS related data to the Linux - VM Monitor Stream, like CPU utilisation, etc. Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM APPLDATA monitor record, i.e. enables or disables monitoring this record on the z/VM side. Default is disabled. This can also be compiled as a module, which will be called appldata_os.o. config APPLDATA_NET_SUM tristate "Monitor overall network statistics" depends on APPLDATA_BASE && NET help This provides network related data to the Linux - VM Monitor Stream, currently there is only a total sum of network I/O statistics, no per-interface data. Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM APPLDATA monitor record, i.e. enables or disables monitoring this record on the z/VM side. Default is disabled. This can also be compiled as a module, which will be called appldata_net_sum.o. source kernel/Kconfig.hz config S390_HYPFS_FS bool "s390 hypervisor file system support" select SYS_HYPERVISOR default y help This is a virtual file system intended to provide accounting information in an s390 hypervisor environment. config KEXEC bool "kexec system call" help kexec is a system call that implements the ability to shutdown your current kernel, and to start another kernel. It is like a reboot but is independent of hardware/microcode support. config ZFCPDUMP bool "zfcpdump support" select SMP default n help Select this option if you want to build an zfcpdump enabled kernel. Refer to for more details on this. config S390_GUEST bool "s390 guest support for KVM (EXPERIMENTAL)" depends on 64BIT && EXPERIMENTAL select VIRTIO select VIRTIO_RING select VIRTIO_CONSOLE help Select this option if you want to run the kernel as a guest under the KVM hypervisor. This will add detection for KVM as well as a virtio transport. If KVM is detected, the virtio console will be the default console. config SECCOMP bool "Enable seccomp to safely compute untrusted bytecode" depends on PROC_FS default y help This kernel feature is useful for number crunching applications that may need to compute untrusted bytecode during their execution. By using pipes or other transports made available to the process as file descriptors supporting the read/write syscalls, it's possible to isolate those applications in their own address space using seccomp. Once seccomp is enabled via /proc//seccomp, it cannot be disabled and the task is only allowed to execute a few safe syscalls defined by each seccomp mode. If unsure, say Y. endmenu menu "Power Management" source "kernel/power/Kconfig" endmenu source "net/Kconfig" config PCMCIA def_bool n config CCW def_bool y source "drivers/Kconfig" source "fs/Kconfig" source "arch/s390/Kconfig.debug" source "security/Kconfig" source "crypto/Kconfig" source "lib/Kconfig" source "arch/s390/kvm/Kconfig"