1
linux/arch/s390/Kconfig
Dave Vasilevsky 31daa34315 crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32
Fixes boot failures on 6.9 on PPC_BOOK3S_32 machines using Open Firmware. 
On these machines, the kernel refuses to boot from non-zero
PHYSICAL_START, which occurs when CRASH_DUMP is on.

Since most PPC_BOOK3S_32 machines boot via Open Firmware, it should
default to off for them.  Users booting via some other mechanism can still
turn it on explicitly.

Does not change the default on any other architectures for the
time being.

Link: https://lkml.kernel.org/r/20240917163720.1644584-1-dave@vasilevsky.ca
Fixes: 75bc255a74 ("crash: clean up kdump related config items")
Signed-off-by: Dave Vasilevsky <dave@vasilevsky.ca>
Reported-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Closes: https://lists.debian.org/debian-powerpc/2024/07/msg00001.html
Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-14 22:43:48 -08:00

1011 lines
27 KiB
Plaintext

# SPDX-License-Identifier: GPL-2.0
config MMU
def_bool y
config CPU_BIG_ENDIAN
def_bool y
config LOCKDEP_SUPPORT
def_bool y
config STACKTRACE_SUPPORT
def_bool y
config ARCH_HAS_ILOG2_U32
def_bool n
config ARCH_HAS_ILOG2_U64
def_bool n
config ARCH_PROC_KCORE_TEXT
def_bool y
config GENERIC_HWEIGHT
def_bool !HAVE_MARCH_Z196_FEATURES
config GENERIC_BUG
def_bool y if BUG
config GENERIC_BUG_RELATIVE_POINTERS
def_bool y
config GENERIC_LOCKBREAK
def_bool y if PREEMPTION
config PGSTE
def_bool y if KVM
config AUDIT_ARCH
def_bool y
config NO_IOPORT_MAP
def_bool y
config PCI_QUIRKS
def_bool n
config ARCH_SUPPORTS_UPROBES
def_bool y
config KASAN_SHADOW_OFFSET
hex
depends on KASAN
default 0x1C000000000000
config S390
def_bool y
#
# Note: keep this list sorted alphabetically
#
imply IMA_SECURE_AND_OR_TRUSTED_BOOT
select ALTERNATE_USER_ADDRESS_SPACE
select ARCH_32BIT_USTAT_F_TINODE
select ARCH_BINFMT_ELF_STATE
select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM
select ARCH_ENABLE_MEMORY_HOTREMOVE
select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
select ARCH_HAS_CURRENT_STACK_POINTER
select ARCH_HAS_DEBUG_VIRTUAL
select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DEBUG_WX
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_DMA_OPS if PCI
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORCE_DMA_UNENCRYPTED
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_GIGANTIC_PAGE
select ARCH_HAS_KCOV
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_MEM_ENCRYPT
select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SCALED_CPUTIME
select ARCH_HAS_SET_DIRECT_MAP
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_UBSAN
select ARCH_HAS_VDSO_DATA
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_INLINE_READ_LOCK
select ARCH_INLINE_READ_LOCK_BH
select ARCH_INLINE_READ_LOCK_IRQ
select ARCH_INLINE_READ_LOCK_IRQSAVE
select ARCH_INLINE_READ_TRYLOCK
select ARCH_INLINE_READ_UNLOCK
select ARCH_INLINE_READ_UNLOCK_BH
select ARCH_INLINE_READ_UNLOCK_IRQ
select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
select ARCH_INLINE_SPIN_LOCK
select ARCH_INLINE_SPIN_LOCK_BH
select ARCH_INLINE_SPIN_LOCK_IRQ
select ARCH_INLINE_SPIN_LOCK_IRQSAVE
select ARCH_INLINE_SPIN_TRYLOCK
select ARCH_INLINE_SPIN_TRYLOCK_BH
select ARCH_INLINE_SPIN_UNLOCK
select ARCH_INLINE_SPIN_UNLOCK_BH
select ARCH_INLINE_SPIN_UNLOCK_IRQ
select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
select ARCH_INLINE_WRITE_LOCK
select ARCH_INLINE_WRITE_LOCK_BH
select ARCH_INLINE_WRITE_LOCK_IRQ
select ARCH_INLINE_WRITE_LOCK_IRQSAVE
select ARCH_INLINE_WRITE_TRYLOCK
select ARCH_INLINE_WRITE_UNLOCK
select ARCH_INLINE_WRITE_UNLOCK_BH
select ARCH_INLINE_WRITE_UNLOCK_IRQ
select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
select ARCH_STACKWALK
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC
select ARCH_SUPPORTS_HUGETLBFS
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && CC_IS_CLANG
select ARCH_SUPPORTS_NUMA_BALANCING
select ARCH_SUPPORTS_PER_VMA_LOCK
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF
select ARCH_USE_SYM_ANNOTATIONS
select ARCH_WANTS_NO_INSTR
select ARCH_WANT_DEFAULT_BPF_JIT
select ARCH_WANT_IPC_PARSE_VERSION
select ARCH_WANT_KERNEL_PMD_MKWRITE
select ARCH_WANT_LD_ORPHAN_WARN
select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
select BUILDTIME_TABLE_SORT
select CLONE_BACKWARDS2
select DCACHE_WORD_ACCESS if !KMSAN
select DYNAMIC_FTRACE if FUNCTION_TRACER
select FUNCTION_ALIGNMENT_8B if CC_IS_GCC
select FUNCTION_ALIGNMENT_16B if !CC_IS_GCC
select GENERIC_ALLOCATOR
select GENERIC_CPU_DEVICES
select GENERIC_CPU_AUTOPROBE
select GENERIC_CPU_VULNERABILITIES
select GENERIC_ENTRY
select GENERIC_GETTIMEOFDAY
select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_VDSO_TIME_NS
select GENERIC_IOREMAP if PCI
select HAVE_ALIGNED_STRUCT_PAGE
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL
select HAVE_ARCH_JUMP_LABEL_RELATIVE
select HAVE_ARCH_KASAN
select HAVE_ARCH_KASAN_VMALLOC
select HAVE_ARCH_KCSAN
select HAVE_ARCH_KMSAN
select HAVE_ARCH_KFENCE
select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
select HAVE_ARCH_SECCOMP_FILTER
select HAVE_ARCH_SOFT_DIRTY
select HAVE_ARCH_STACKLEAK
select HAVE_ARCH_TRACEHOOK
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
select HAVE_ARCH_VMAP_STACK
select HAVE_ASM_MODVERSIONS
select HAVE_CMPXCHG_DOUBLE
select HAVE_CMPXCHG_LOCAL
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_CONTIGUOUS
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_ARGS
select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
select HAVE_DYNAMIC_FTRACE_WITH_REGS
select HAVE_EBPF_JIT if HAVE_MARCH_Z196_FEATURES
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select HAVE_GUP_FAST
select HAVE_FENTRY
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_FUNCTION_ARG_ACCESS_API
select HAVE_FUNCTION_ERROR_INJECTION
select HAVE_FUNCTION_GRAPH_RETVAL
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_TRACER
select HAVE_GCC_PLUGINS
select HAVE_GENERIC_VDSO
select HAVE_IOREMAP_PROT if PCI
select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_KERNEL_UNCOMPRESSED
select HAVE_KERNEL_XZ
select HAVE_KERNEL_ZSTD
select HAVE_KPROBES
select HAVE_KPROBES_ON_FTRACE
select HAVE_KRETPROBES
select HAVE_LIVEPATCH
select HAVE_MEMBLOCK_PHYS_MAP
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_NMI
select HAVE_NOP_MCOUNT
select HAVE_PAGE_SIZE_4KB
select HAVE_PCI
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_RELIABLE_STACKTRACE
select HAVE_RETHOOK
select HAVE_RSEQ
select HAVE_SAMPLE_FTRACE_DIRECT
select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
select HAVE_SETUP_PER_CPU_AREA
select HAVE_SOFTIRQ_ON_OWN_STACK
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
select HAVE_VIRT_CPU_ACCOUNTING_IDLE
select IOMMU_HELPER if PCI
select IOMMU_SUPPORT if PCI
select MMU_GATHER_MERGE_VMAS
select MMU_GATHER_NO_GATHER
select MMU_GATHER_RCU_TABLE_FREE
select MODULES_USE_ELF_RELA
select NEED_DMA_MAP_STATE if PCI
select NEED_PER_CPU_EMBED_FIRST_CHUNK
select NEED_SG_DMA_LENGTH if PCI
select OLD_SIGACTION
select OLD_SIGSUSPEND3
select PCI_DOMAINS if PCI
select PCI_MSI if PCI
select PCI_MSI_ARCH_FALLBACKS if PCI_MSI
select SPARSE_IRQ
select SWIOTLB
select SYSCTL_EXCEPTION_TRACE
select THREAD_INFO_IN_TASK
select TRACE_IRQFLAGS_SUPPORT
select TTY
select USER_STACKTRACE_SUPPORT
select VDSO_GETRANDOM
select VIRT_CPU_ACCOUNTING
select ZONE_DMA
# Note: keep the above list sorted alphabetically
config SCHED_OMIT_FRAME_POINTER
def_bool y
config PGTABLE_LEVELS
int
default 5
source "kernel/livepatch/Kconfig"
config ARCH_SUPPORTS_KEXEC
def_bool y
config ARCH_SUPPORTS_KEXEC_FILE
def_bool y
config ARCH_SUPPORTS_KEXEC_SIG
def_bool MODULE_SIG_FORMAT
config ARCH_SUPPORTS_KEXEC_PURGATORY
def_bool y
config ARCH_SUPPORTS_CRASH_DUMP
def_bool y
help
Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this.
This option also enables s390 zfcpdump.
See also <file:Documentation/arch/s390/zfcpdump.rst>
config ARCH_DEFAULT_CRASH_DUMP
def_bool y
menu "Processor type and features"
config HAVE_MARCH_Z10_FEATURES
def_bool n
config HAVE_MARCH_Z196_FEATURES
def_bool n
select HAVE_MARCH_Z10_FEATURES
config HAVE_MARCH_ZEC12_FEATURES
def_bool n
select HAVE_MARCH_Z196_FEATURES
config HAVE_MARCH_Z13_FEATURES
def_bool n
select HAVE_MARCH_ZEC12_FEATURES
config HAVE_MARCH_Z14_FEATURES
def_bool n
select HAVE_MARCH_Z13_FEATURES
config HAVE_MARCH_Z15_FEATURES
def_bool n
select HAVE_MARCH_Z14_FEATURES
config HAVE_MARCH_Z16_FEATURES
def_bool n
select HAVE_MARCH_Z15_FEATURES
choice
prompt "Processor type"
default MARCH_Z196
config MARCH_Z10
bool "IBM System z10"
select HAVE_MARCH_Z10_FEATURES
depends on $(cc-option,-march=z10)
help
Select this to enable optimizations for IBM System z10 (2097 and 2098
series). This is the oldest machine generation currently supported.
config MARCH_Z196
bool "IBM zEnterprise 114 and 196"
select HAVE_MARCH_Z196_FEATURES
depends on $(cc-option,-march=z196)
help
Select this to enable optimizations for IBM zEnterprise 114 and 196
(2818 and 2817 series). The kernel will be slightly faster but will
not work on older machines.
config MARCH_ZEC12
bool "IBM zBC12 and zEC12"
select HAVE_MARCH_ZEC12_FEATURES
depends on $(cc-option,-march=zEC12)
help
Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
2827 series). The kernel will be slightly faster but will not work on
older machines.
config MARCH_Z13
bool "IBM z13s and z13"
select HAVE_MARCH_Z13_FEATURES
depends on $(cc-option,-march=z13)
help
Select this to enable optimizations for IBM z13s and z13 (2965 and
2964 series). The kernel will be slightly faster but will not work on
older machines.
config MARCH_Z14
bool "IBM z14 ZR1 and z14"
select HAVE_MARCH_Z14_FEATURES
depends on $(cc-option,-march=z14)
help
Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
and 3906 series). The kernel will be slightly faster but will not
work on older machines.
config MARCH_Z15
bool "IBM z15"
select HAVE_MARCH_Z15_FEATURES
depends on $(cc-option,-march=z15)
help
Select this to enable optimizations for IBM z15 (8562
and 8561 series). The kernel will be slightly faster but will not
work on older machines.
config MARCH_Z16
bool "IBM z16"
select HAVE_MARCH_Z16_FEATURES
depends on $(cc-option,-march=z16)
help
Select this to enable optimizations for IBM z16 (3931 and
3932 series).
endchoice
config MARCH_Z10_TUNE
def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
config MARCH_Z196_TUNE
def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
config MARCH_ZEC12_TUNE
def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
config MARCH_Z13_TUNE
def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
config MARCH_Z14_TUNE
def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
config MARCH_Z15_TUNE
def_bool TUNE_Z15 || MARCH_Z15 && TUNE_DEFAULT
config MARCH_Z16_TUNE
def_bool TUNE_Z16 || MARCH_Z16 && TUNE_DEFAULT
choice
prompt "Tune code generation"
default TUNE_DEFAULT
help
Cause the compiler to tune (-mtune) the generated code for a machine.
This will make the code run faster on the selected machine but
somewhat slower on other machines.
This option only changes how the compiler emits instructions, not the
selection of instructions itself, so the resulting kernel will run on
all other machines.
config TUNE_DEFAULT
bool "Default"
help
Tune the generated code for the target processor for which the kernel
will be compiled.
config TUNE_Z10
bool "IBM System z10"
config TUNE_Z196
bool "IBM zEnterprise 114 and 196"
depends on $(cc-option,-mtune=z196)
config TUNE_ZEC12
bool "IBM zBC12 and zEC12"
depends on $(cc-option,-mtune=zEC12)
config TUNE_Z13
bool "IBM z13s and z13"
depends on $(cc-option,-mtune=z13)
config TUNE_Z14
bool "IBM z14 ZR1 and z14"
depends on $(cc-option,-mtune=z14)
config TUNE_Z15
bool "IBM z15"
depends on $(cc-option,-mtune=z15)
config TUNE_Z16
bool "IBM z16"
depends on $(cc-option,-mtune=z16)
endchoice
config 64BIT
def_bool y
config COMMAND_LINE_SIZE
int "Maximum size of kernel command line"
default 4096
range 896 1048576
help
This allows you to specify the maximum length of the kernel command
line.
config COMPAT
def_bool n
prompt "Kernel support for 31 bit emulation"
select ARCH_WANT_OLD_COMPAT_IPC
select COMPAT_OLD_SIGACTION
select HAVE_UID16
depends on MULTIUSER
depends on !CC_IS_CLANG && !LD_IS_LLD
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.
If unsure say N.
config SMP
def_bool y
config NR_CPUS
int "Maximum number of CPUs (2-512)"
range 2 512
default "64"
help
This allows you to specify the maximum number of CPUs which this
kernel will support. The maximum supported value is 512 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
def_bool y
config NUMA
bool "NUMA support"
depends on SCHED_TOPOLOGY
default n
help
Enable NUMA support
This option adds NUMA support to the kernel.
config NODES_SHIFT
int
depends on NUMA
default "1"
config SCHED_SMT
def_bool n
config SCHED_MC
def_bool n
config SCHED_TOPOLOGY
def_bool y
prompt "Topology scheduler support"
select SCHED_SMT
select SCHED_MC
help
Topology scheduler support improves the CPU scheduler's decision
making when dealing with machines that have multi-threading,
multiple cores or multiple books.
config SCHED_TOPOLOGY_VERTICAL
def_bool y
bool "Use vertical CPU polarization by default"
depends on SCHED_TOPOLOGY
help
Use vertical CPU polarization by default if available.
The default CPU polarization is horizontal.
config HIPERDISPATCH_ON
def_bool y
bool "Use hiperdispatch on vertical polarization by default"
depends on SCHED_TOPOLOGY
depends on PROC_SYSCTL
help
Hiperdispatch aims to improve the CPU scheduler's decision
making when using vertical polarization by adjusting CPU
capacities dynamically. Set this option to use hiperdispatch
on vertical polarization by default. This can be overwritten
by sysctl's s390.hiperdispatch attribute later on.
source "kernel/Kconfig.hz"
config CERT_STORE
bool "Get user certificates via DIAG320"
depends on KEYS
select CRYPTO_LIB_SHA256
help
Enable this option if you want to access user-provided secure boot
certificates via DIAG 0x320.
These certificates will be made available via the keyring named
'cert_store'.
config KERNEL_NOBP
def_bool n
prompt "Enable modified branch prediction for the kernel by default"
help
If this option is selected the kernel will switch to a modified
branch prediction mode if the firmware interface is available.
The modified branch prediction mode improves the behaviour in
regard to speculative execution.
With the option enabled the kernel parameter "nobp=0" or "nospec"
can be used to run the kernel in the normal branch prediction mode.
With the option disabled the modified branch prediction mode is
enabled with the "nobp=1" kernel parameter.
If unsure, say N.
config EXPOLINE
def_bool n
depends on $(cc-option,-mindirect-branch=thunk)
prompt "Avoid speculative indirect branches in the kernel"
help
Compile the kernel with the expoline compiler options to guard
against kernel-to-user data leaks by avoiding speculative indirect
branches.
Requires a compiler with -mindirect-branch=thunk support for full
protection. The kernel may run slower.
If unsure, say N.
config EXPOLINE_EXTERN
def_bool EXPOLINE && CC_IS_GCC && GCC_VERSION >= 110200 && \
$(success,$(srctree)/arch/s390/tools/gcc-thunk-extern.sh $(CC))
help
Generate expolines as external functions if the compiler supports it.
This option is required for some tooling like kpatch, if expolines
are enabled. The kernel is compiled with
-mindirect-branch=thunk-extern, which requires a newer compiler.
choice
prompt "Expoline default"
depends on EXPOLINE
default EXPOLINE_FULL
config EXPOLINE_OFF
bool "spectre_v2=off"
config EXPOLINE_AUTO
bool "spectre_v2=auto"
config EXPOLINE_FULL
bool "spectre_v2=on"
endchoice
config RELOCATABLE
def_bool y
help
This builds a kernel image that retains relocation information
so it can be loaded at an arbitrary address.
The relocations make the kernel image about 15% larger (compressed
10%), but are discarded at runtime.
Note: this option exists only for documentation purposes, please do
not remove it.
config RANDOMIZE_BASE
bool "Randomize the address of the kernel image (KASLR)"
default y
help
In support of Kernel Address Space Layout Randomization (KASLR),
this randomizes the address at which the kernel image is loaded,
as a security feature that deters exploit attempts relying on
knowledge of the location of kernel internals.
config RANDOMIZE_IDENTITY_BASE
bool "Randomize the address of the identity mapping base"
depends on RANDOMIZE_BASE
default DEBUG_VM
help
The identity mapping base address is pinned to zero by default.
Allow randomization of that base to expose otherwise missed
notion of physical and virtual addresses of data structures.
That does not have any impact on the base address at which the
kernel image is loaded.
If unsure, say N
config KERNEL_IMAGE_BASE
hex "Kernel image base address"
range 0x100000 0x1FFFFFE0000000 if !KASAN
range 0x100000 0x1BFFFFE0000000 if KASAN
default 0x3FFE0000000 if !KASAN
default 0x7FFFE0000000 if KASAN
help
This is the address at which the kernel image is loaded in case
Kernel Address Space Layout Randomization (KASLR) is disabled.
In case the Protected virtualization guest support is enabled the
Ultravisor imposes a virtual address limit. If the value of this
option leads to the kernel image exceeding the Ultravisor limit,
this option is ignored and the image is loaded below the limit.
If the value of this option leads to the kernel image overlapping
the virtual memory where other data structures are located, this
option is ignored and the image is loaded above the structures.
endmenu
menu "Memory setup"
config ARCH_SPARSEMEM_ENABLE
def_bool y
select SPARSEMEM_VMEMMAP_ENABLE
select SPARSEMEM_VMEMMAP
config ARCH_SPARSEMEM_DEFAULT
def_bool y
config MAX_PHYSMEM_BITS
int "Maximum size of supported physical memory in bits (42-53)"
range 42 53
default "46"
help
This option specifies the maximum supported size of physical memory
in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
Increasing the number of bits also increases the kernel image size.
By default 46 bits (64TB) are supported.
config CHECK_STACK
def_bool y
depends on !VMAP_STACK
prompt "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.
endmenu
menu "I/O subsystem"
config QDIO
def_tristate y
prompt "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.
if PCI
config PCI_NR_FUNCTIONS
int "Maximum number of PCI functions (1-4096)"
range 1 4096
default "512"
help
This allows you to specify the maximum number of PCI functions which
this kernel will support.
endif # PCI
config HAS_IOMEM
def_bool PCI
config CHSC_SCH
def_tristate m
prompt "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.
config SCM_BUS
def_bool y
prompt "SCM bus driver"
help
Bus driver for Storage Class Memory.
config EADM_SCH
def_tristate m
prompt "Support for EADM subchannels"
depends on SCM_BUS
help
This driver allows usage of EADM subchannels. EADM subchannels act
as a communication vehicle for SCM increments.
To compile this driver as a module, choose M here: the
module will be called eadm_sch.
config AP
def_tristate y
prompt "Support for Adjunct Processors (ap)"
help
This driver allows usage to Adjunct Processor (AP) devices via
the ap bus, cards and queues. Supported Adjunct Processors are
the CryptoExpress Cards (CEX).
To compile this driver as a module, choose M here: the
module will be called ap.
If unsure, say Y (default).
config AP_DEBUG
def_bool n
prompt "Enable debug features for Adjunct Processor (ap) devices"
depends on AP
help
Say 'Y' here to enable some additional debug features for Adjunct
Processor (ap) devices.
There will be some more sysfs attributes displayed for ap queues.
Do not enable on production level kernel build.
If unsure, say N.
config VFIO_CCW
def_tristate n
prompt "Support for VFIO-CCW subchannels"
depends on VFIO
select VFIO_MDEV
help
This driver allows usage of I/O subchannels via VFIO-CCW.
To compile this driver as a module, choose M here: the
module will be called vfio_ccw.
config VFIO_AP
def_tristate n
prompt "VFIO support for AP devices"
depends on KVM
depends on VFIO
depends on AP
select VFIO_MDEV
help
This driver grants access to Adjunct Processor (AP) devices
via the VFIO mediated device interface.
To compile this driver as a module, choose M here: the module
will be called vfio_ap.
endmenu
config CCW
def_bool y
config HAVE_PNETID
tristate
default (SMC || CCWGROUP)
menu "Virtualization"
config PFAULT
def_bool y
prompt "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 CMM
def_tristate n
prompt "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_IUCV
def_bool y
prompt "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 APPLDATA_BASE
def_bool n
prompt "Linux - VM Monitor Stream, base infrastructure"
depends on PROC_SYSCTL
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
def_tristate m
prompt "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
def_tristate m
prompt "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
def_tristate m
prompt "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.
config S390_HYPFS
def_bool y
prompt "s390 hypervisor information"
help
This provides several binary files at (debugfs)/s390_hypfs/ to
provide accounting information in an s390 hypervisor environment.
config S390_HYPFS_FS
def_bool n
prompt "s390 hypervisor file system support"
select SYS_HYPERVISOR
depends on S390_HYPFS
help
This is a virtual file system intended to provide accounting
information in an s390 hypervisor environment. This file system
is deprecated and should not be used.
Say N if you are unsure.
source "arch/s390/kvm/Kconfig"
config S390_GUEST
def_bool y
prompt "s390 support for virtio devices"
select TTY
select VIRTUALIZATION
select VIRTIO
help
Enabling this option adds support for virtio based paravirtual device
drivers on s390.
Select this option if you want to run the kernel as a guest under
the KVM hypervisor.
endmenu
config S390_MODULES_SANITY_TEST_HELPERS
def_bool n
menu "Selftests"
config S390_UNWIND_SELFTEST
def_tristate n
depends on KUNIT
default KUNIT_ALL_TESTS
prompt "Test unwind functions"
help
This option enables s390 specific stack unwinder testing kernel
module. This option is not useful for distributions or general
kernels, but only for kernel developers working on architecture code.
Say N if you are unsure.
config S390_KPROBES_SANITY_TEST
def_tristate n
prompt "Enable s390 specific kprobes tests"
depends on KPROBES
depends on KUNIT
help
This option enables an s390 specific kprobes test module. This option
is not useful for distributions or general kernels, but only for kernel
developers working on architecture code.
Say N if you are unsure.
config S390_MODULES_SANITY_TEST
def_tristate n
depends on KUNIT
default KUNIT_ALL_TESTS
prompt "Enable s390 specific modules tests"
select S390_MODULES_SANITY_TEST_HELPERS
help
This option enables an s390 specific modules test. This option is
not useful for distributions or general kernels, but only for
kernel developers working on architecture code.
Say N if you are unsure.
endmenu