mirror of https://github.com/hak5/openwrt.git
1060 lines
30 KiB
Plaintext
1060 lines
30 KiB
Plaintext
# Copyright (C) 2006-2014 OpenWrt.org
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#
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# This is free software, licensed under the GNU General Public License v2.
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# See /LICENSE for more information.
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#
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config KERNEL_BUILD_USER
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string "Custom Kernel Build User Name"
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default "builder" if BUILDBOT
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default ""
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help
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Sets the Kernel build user string, which for example will be returned
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by 'uname -a' on running systems.
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If not set, uses system user at build time.
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config KERNEL_BUILD_DOMAIN
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string "Custom Kernel Build Domain Name"
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default "buildhost" if BUILDBOT
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default ""
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help
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Sets the Kernel build domain string, which for example will be
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returned by 'uname -a' on running systems.
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If not set, uses system hostname at build time.
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config KERNEL_PRINTK
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bool "Enable support for printk"
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default y
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config KERNEL_CRASHLOG
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bool "Crash logging"
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depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
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default y
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config KERNEL_SWAP
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bool "Support for paging of anonymous memory (swap)"
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default y if !SMALL_FLASH
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config KERNEL_DEBUG_FS
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bool "Compile the kernel with debug filesystem enabled"
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default y
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help
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debugfs is a virtual file system that kernel developers use to put
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debugging files into. Enable this option to be able to read and
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write to these files. Many common debugging facilities, such as
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ftrace, require the existence of debugfs.
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# remove KERNEL_MIPS_FPU_EMULATOR after kernel 4.14 and 4.14 are gone
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config KERNEL_MIPS_FPU_EMULATOR
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bool "Compile the kernel with MIPS FPU Emulator"
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default y if TARGET_pistachio
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depends on (mips || mipsel || mips64 || mips64el)
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config KERNEL_MIPS_FP_SUPPORT
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bool
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default y if KERNEL_MIPS_FPU_EMULATOR
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config KERNEL_ARM_PMU
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bool
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default n
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depends on (arm || aarch64)
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config KERNEL_X86_VSYSCALL_EMULATION
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bool "Enable vsyscall emulation"
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default n
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depends on x86_64
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help
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This enables emulation of the legacy vsyscall page. Disabling
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it is roughly equivalent to booting with vsyscall=none, except
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that it will also disable the helpful warning if a program
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tries to use a vsyscall. With this option set to N, offending
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programs will just segfault, citing addresses of the form
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0xffffffffff600?00.
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This option is required by many programs built before 2013, and
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care should be used even with newer programs if set to N.
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Disabling this option saves about 7K of kernel size and
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possibly 4K of additional runtime pagetable memory.
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config KERNEL_PERF_EVENTS
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bool "Compile the kernel with performance events and counters"
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default n
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select KERNEL_ARM_PMU if (arm || aarch64)
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config KERNEL_PROFILING
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bool "Compile the kernel with profiling enabled"
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default n
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select KERNEL_PERF_EVENTS
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help
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Enable the extended profiling support mechanisms used by profilers such
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as OProfile.
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config KERNEL_UBSAN
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bool "Compile the kernel with undefined behaviour sanity checker"
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help
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This option enables undefined behaviour sanity checker
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Compile-time instrumentation is used to detect various undefined
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behaviours in runtime. Various types of checks may be enabled
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via boot parameter ubsan_handle
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(see: Documentation/dev-tools/ubsan.rst).
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config KERNEL_UBSAN_SANITIZE_ALL
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bool "Enable instrumentation for the entire kernel"
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depends on KERNEL_UBSAN
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default y
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help
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This option activates instrumentation for the entire kernel.
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If you don't enable this option, you have to explicitly specify
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UBSAN_SANITIZE := y for the files/directories you want to check for UB.
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Enabling this option will get kernel image size increased
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significantly.
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config KERNEL_UBSAN_ALIGNMENT
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bool "Enable checking of pointers alignment"
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depends on KERNEL_UBSAN
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help
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This option enables detection of unaligned memory accesses.
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Enabling this option on architectures that support unaligned
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accesses may produce a lot of false positives.
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config KERNEL_UBSAN_NULL
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bool "Enable checking of null pointers"
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depends on KERNEL_UBSAN
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help
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This option enables detection of memory accesses via a
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null pointer.
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config KERNEL_KASAN
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bool "Compile the kernel with KASan: runtime memory debugger"
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select KERNEL_SLUB_DEBUG
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depends on (x86_64 || aarch64)
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help
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Enables kernel address sanitizer - runtime memory debugger,
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designed to find out-of-bounds accesses and use-after-free bugs.
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This is strictly a debugging feature and it requires a gcc version
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of 4.9.2 or later. Detection of out of bounds accesses to stack or
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global variables requires gcc 5.0 or later.
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This feature consumes about 1/8 of available memory and brings about
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~x3 performance slowdown.
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For better error detection enable CONFIG_STACKTRACE.
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Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
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(the resulting kernel does not boot).
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config KERNEL_KASAN_EXTRA
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bool "KAsan: extra checks"
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depends on KERNEL_KASAN && KERNEL_DEBUG_KERNEL
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help
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This enables further checks in the kernel address sanitizer, for now
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it only includes the address-use-after-scope check that can lead
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to excessive kernel stack usage, frame size warnings and longer
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compile time.
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more
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choice
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prompt "Instrumentation type"
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depends on KERNEL_KASAN
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default KERNEL_KASAN_OUTLINE
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config KERNEL_KASAN_OUTLINE
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bool "Outline instrumentation"
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help
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Before every memory access compiler insert function call
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__asan_load*/__asan_store*. These functions performs check
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of shadow memory. This is slower than inline instrumentation,
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however it doesn't bloat size of kernel's .text section so
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much as inline does.
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config KERNEL_KASAN_INLINE
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bool "Inline instrumentation"
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help
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Compiler directly inserts code checking shadow memory before
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memory accesses. This is faster than outline (in some workloads
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it gives about x2 boost over outline instrumentation), but
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make kernel's .text size much bigger.
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This requires a gcc version of 5.0 or later.
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endchoice
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config KERNEL_KCOV
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bool "Compile the kernel with code coverage for fuzzing"
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select KERNEL_DEBUG_FS
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help
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KCOV exposes kernel code coverage information in a form suitable
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for coverage-guided fuzzing (randomized testing).
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If RANDOMIZE_BASE is enabled, PC values will not be stable across
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different machines and across reboots. If you need stable PC values,
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disable RANDOMIZE_BASE.
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For more details, see Documentation/kcov.txt.
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config KERNEL_KCOV_ENABLE_COMPARISONS
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bool "Enable comparison operands collection by KCOV"
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depends on KERNEL_KCOV
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help
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KCOV also exposes operands of every comparison in the instrumented
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code along with operand sizes and PCs of the comparison instructions.
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These operands can be used by fuzzing engines to improve the quality
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of fuzzing coverage.
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config KERNEL_KCOV_INSTRUMENT_ALL
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bool "Instrument all code by default"
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depends on KERNEL_KCOV
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default y if KERNEL_KCOV
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help
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If you are doing generic system call fuzzing (like e.g. syzkaller),
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then you will want to instrument the whole kernel and you should
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say y here. If you are doing more targeted fuzzing (like e.g.
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filesystem fuzzing with AFL) then you will want to enable coverage
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for more specific subsets of files, and should say n here.
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config KERNEL_TASKSTATS
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bool "Compile the kernel with task resource/io statistics and accounting"
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default n
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help
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Enable the collection and publishing of task/io statistics and
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accounting. Enable this option to enable i/o monitoring in system
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monitors.
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if KERNEL_TASKSTATS
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config KERNEL_TASK_DELAY_ACCT
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def_bool y
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config KERNEL_TASK_IO_ACCOUNTING
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def_bool y
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config KERNEL_TASK_XACCT
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def_bool y
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endif
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config KERNEL_KALLSYMS
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bool "Compile the kernel with symbol table information"
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default y if !SMALL_FLASH
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help
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This will give you more information in stack traces from kernel oopses.
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config KERNEL_FTRACE
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bool "Compile the kernel with tracing support"
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depends on !TARGET_uml
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default n
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config KERNEL_FTRACE_SYSCALLS
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bool "Trace system calls"
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depends on KERNEL_FTRACE
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default n
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config KERNEL_ENABLE_DEFAULT_TRACERS
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bool "Trace process context switches and events"
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depends on KERNEL_FTRACE
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default n
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config KERNEL_FUNCTION_TRACER
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bool "Function tracer"
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depends on KERNEL_FTRACE
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default n
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config KERNEL_FUNCTION_GRAPH_TRACER
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bool "Function graph tracer"
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depends on KERNEL_FUNCTION_TRACER
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default n
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config KERNEL_DYNAMIC_FTRACE
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bool "Enable/disable function tracing dynamically"
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depends on KERNEL_FUNCTION_TRACER
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default n
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config KERNEL_FUNCTION_PROFILER
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bool "Function profiler"
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depends on KERNEL_FUNCTION_TRACER
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default n
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config KERNEL_DEBUG_KERNEL
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bool
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default n
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config KERNEL_DEBUG_INFO
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bool "Compile the kernel with debug information"
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default y if !SMALL_FLASH
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select KERNEL_DEBUG_KERNEL
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help
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This will compile your kernel and modules with debug information.
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config KERNEL_DEBUG_LL_UART_NONE
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bool
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default n
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depends on arm
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config KERNEL_DEBUG_LL
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bool
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default n
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depends on arm
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select KERNEL_DEBUG_LL_UART_NONE
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help
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ARM low level debugging.
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config KERNEL_DYNAMIC_DEBUG
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bool "Compile the kernel with dynamic printk"
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select KERNEL_DEBUG_FS
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default n
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help
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Compiles debug level messages into the kernel, which would not
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otherwise be available at runtime. These messages can then be
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enabled/disabled based on various levels of scope - per source file,
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function, module, format string, and line number. This mechanism
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implicitly compiles in all pr_debug() and dev_dbg() calls, which
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enlarges the kernel text size by about 2%.
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config KERNEL_EARLY_PRINTK
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bool "Compile the kernel with early printk"
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default y if TARGET_bcm53xx
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default n
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depends on arm
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select KERNEL_DEBUG_KERNEL
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select KERNEL_DEBUG_LL if arm
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help
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Compile the kernel with early printk support. This is only useful for
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debugging purposes to send messages over the serial console in early boot.
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Enable this to debug early boot problems.
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config KERNEL_KPROBES
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bool "Compile the kernel with kprobes support"
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default n
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select KERNEL_FTRACE
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select KERNEL_PERF_EVENTS
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help
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Compiles the kernel with KPROBES support, which allows you to trap
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at almost any kernel address and execute a callback function.
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register_kprobe() establishes a probepoint and specifies the
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callback. Kprobes is useful for kernel debugging, non-intrusive
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instrumentation and testing.
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If in doubt, say "N".
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config KERNEL_KPROBE_EVENT
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bool
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default y if KERNEL_KPROBES
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config KERNEL_KPROBE_EVENTS
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bool
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default y if KERNEL_KPROBES
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config KERNEL_AIO
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bool "Compile the kernel with asynchronous IO support"
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default y if !SMALL_FLASH
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config KERNEL_FHANDLE
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bool "Compile the kernel with support for fhandle syscalls"
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default y if !SMALL_FLASH
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config KERNEL_FANOTIFY
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bool "Compile the kernel with modern file notification support"
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default y if !SMALL_FLASH
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config KERNEL_BLK_DEV_BSG
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bool "Compile the kernel with SCSI generic v4 support for any block device"
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default n
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config KERNEL_MAGIC_SYSRQ
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bool "Compile the kernel with SysRq support"
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default y
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config KERNEL_DEBUG_PINCTRL
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bool "Compile the kernel with pinctrl debugging"
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select KERNEL_DEBUG_KERNEL
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config KERNEL_DEBUG_GPIO
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bool "Compile the kernel with gpio debugging"
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select KERNEL_DEBUG_KERNEL
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config KERNEL_COREDUMP
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bool
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config KERNEL_ELF_CORE
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bool "Enable process core dump support"
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select KERNEL_COREDUMP
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default y if !SMALL_FLASH
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config KERNEL_PROVE_LOCKING
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bool "Enable kernel lock checking"
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select KERNEL_DEBUG_KERNEL
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default n
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config KERNEL_LOCKUP_DETECTOR
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bool "Compile the kernel with detect Hard and Soft Lockups"
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depends on KERNEL_DEBUG_KERNEL
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help
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Say Y here to enable the kernel to act as a watchdog to detect
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hard and soft lockups.
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Softlockups are bugs that cause the kernel to loop in kernel
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mode for more than 20 seconds, without giving other tasks a
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chance to run. The current stack trace is displayed upon
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detection and the system will stay locked up.
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Hardlockups are bugs that cause the CPU to loop in kernel mode
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for more than 10 seconds, without letting other interrupts have a
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chance to run. The current stack trace is displayed upon detection
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and the system will stay locked up.
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The overhead should be minimal. A periodic hrtimer runs to
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generate interrupts and kick the watchdog task every 4 seconds.
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An NMI is generated every 10 seconds or so to check for hardlockups.
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The frequency of hrtimer and NMI events and the soft and hard lockup
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thresholds can be controlled through the sysctl watchdog_thresh.
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config KERNEL_DETECT_HUNG_TASK
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bool "Compile the kernel with detect Hung Tasks"
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depends on KERNEL_DEBUG_KERNEL
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default KERNEL_LOCKUP_DETECTOR
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help
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Say Y here to enable the kernel to detect "hung tasks",
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which are bugs that cause the task to be stuck in
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uninterruptible "D" state indefinitely.
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When a hung task is detected, the kernel will print the
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current stack trace (which you should report), but the
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task will stay in uninterruptible state. If lockdep is
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enabled then all held locks will also be reported. This
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feature has negligible overhead.
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config KERNEL_WQ_WATCHDOG
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bool "Compile the kernel with detect Workqueue Stalls"
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depends on KERNEL_DEBUG_KERNEL
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help
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Say Y here to enable stall detection on workqueues. If a
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worker pool doesn't make forward progress on a pending work
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item for over a given amount of time, 30s by default, a
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warning message is printed along with dump of workqueue
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state. This can be configured through kernel parameter
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"workqueue.watchdog_thresh" and its sysfs counterpart.
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config KERNEL_DEBUG_ATOMIC_SLEEP
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bool "Compile the kernel with sleep inside atomic section checking"
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depends on KERNEL_DEBUG_KERNEL
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help
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If you say Y here, various routines which may sleep will become very
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noisy if they are called inside atomic sections: when a spinlock is
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held, inside an rcu read side critical section, inside preempt disabled
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sections, inside an interrupt, etc...
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config KERNEL_DEBUG_VM
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bool "Compile the kernel with debug VM"
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depends on KERNEL_DEBUG_KERNEL
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help
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Enable this to turn on extended checks in the virtual-memory system
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that may impact performance.
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If unsure, say N.
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config KERNEL_PRINTK_TIME
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bool "Enable printk timestamps"
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default y
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config KERNEL_SLUB_DEBUG
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bool
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config KERNEL_SLUB_DEBUG_ON
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bool
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config KERNEL_SLABINFO
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select KERNEL_SLUB_DEBUG
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select KERNEL_SLUB_DEBUG_ON
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bool "Enable /proc slab debug info"
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config KERNEL_PROC_PAGE_MONITOR
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bool "Enable /proc page monitoring"
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config KERNEL_RELAY
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bool
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config KERNEL_KEXEC
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bool "Enable kexec support"
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config KERNEL_PROC_VMCORE
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bool
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config KERNEL_PROC_KCORE
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bool
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config KERNEL_CRASH_DUMP
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depends on i386 || x86_64 || arm || armeb
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select KERNEL_KEXEC
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select KERNEL_PROC_VMCORE
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select KERNEL_PROC_KCORE
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bool "Enable support for kexec crashdump"
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default y
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config USE_RFKILL
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bool "Enable rfkill support"
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default RFKILL_SUPPORT
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config USE_SPARSE
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bool "Enable sparse check during kernel build"
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default n
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config KERNEL_DEVTMPFS
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bool "Compile the kernel with device tmpfs enabled"
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default n
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help
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devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
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devices nodes for all registered devices to simplify boot, but leaves more
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complex tasks to userspace (e.g. udev).
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if KERNEL_DEVTMPFS
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config KERNEL_DEVTMPFS_MOUNT
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bool "Automatically mount devtmpfs after root filesystem is mounted"
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default n
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endif
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config KERNEL_KEYS
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bool "Enable kernel access key retention support"
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default n
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config KERNEL_PERSISTENT_KEYRINGS
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bool "Enable kernel persistent keyrings"
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depends on KERNEL_KEYS
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default n
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config KERNEL_BIG_KEYS
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bool "Enable large payload keys on kernel keyrings"
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depends on KERNEL_KEYS
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default n
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config KERNEL_ENCRYPTED_KEYS
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tristate "Enable keys with encrypted payloads on kernel keyrings"
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depends on KERNEL_KEYS
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default n
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#
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# CGROUP support symbols
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#
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config KERNEL_CGROUPS
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bool "Enable kernel cgroups"
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default y if !SMALL_FLASH
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if KERNEL_CGROUPS
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config KERNEL_CGROUP_DEBUG
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bool "Example debug cgroup subsystem"
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default n
|
|
help
|
|
This option enables a simple cgroup subsystem that
|
|
exports useful debugging information about the cgroups
|
|
framework.
|
|
|
|
config KERNEL_FREEZER
|
|
bool
|
|
default y if KERNEL_CGROUP_FREEZER
|
|
|
|
config KERNEL_CGROUP_FREEZER
|
|
bool "Freezer cgroup subsystem"
|
|
default y
|
|
help
|
|
Provides a way to freeze and unfreeze all tasks in a
|
|
cgroup.
|
|
|
|
config KERNEL_CGROUP_DEVICE
|
|
bool "Device controller for cgroups"
|
|
default y
|
|
help
|
|
Provides a cgroup implementing whitelists for devices which
|
|
a process in the cgroup can mknod or open.
|
|
|
|
config KERNEL_CGROUP_PIDS
|
|
bool "PIDs cgroup subsystem"
|
|
default y
|
|
help
|
|
Provides enforcement of process number limits in the scope of a
|
|
cgroup.
|
|
|
|
config KERNEL_CPUSETS
|
|
bool "Cpuset support"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
This option will let you create and manage CPUSETs which
|
|
allow dynamically partitioning a system into sets of CPUs and
|
|
Memory Nodes and assigning tasks to run only within those sets.
|
|
This is primarily useful on large SMP or NUMA systems.
|
|
|
|
config KERNEL_PROC_PID_CPUSET
|
|
bool "Include legacy /proc/<pid>/cpuset file"
|
|
default n
|
|
depends on KERNEL_CPUSETS
|
|
|
|
config KERNEL_CGROUP_CPUACCT
|
|
bool "Simple CPU accounting cgroup subsystem"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
Provides a simple Resource Controller for monitoring the
|
|
total CPU consumed by the tasks in a cgroup.
|
|
|
|
config KERNEL_RESOURCE_COUNTERS
|
|
bool "Resource counters"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
This option enables controller independent resource accounting
|
|
infrastructure that works with cgroups.
|
|
|
|
config KERNEL_MM_OWNER
|
|
bool
|
|
default y if KERNEL_MEMCG
|
|
|
|
config KERNEL_MEMCG
|
|
bool "Memory Resource Controller for Control Groups"
|
|
default y if !SMALL_FLASH
|
|
depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18
|
|
help
|
|
Provides a memory resource controller that manages both anonymous
|
|
memory and page cache. (See Documentation/cgroups/memory.txt)
|
|
|
|
Note that setting this option increases fixed memory overhead
|
|
associated with each page of memory in the system. By this,
|
|
20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
|
|
usage tracking struct at boot. Total amount of this is printed out
|
|
at boot.
|
|
|
|
Only enable when you're ok with these tradeoffs and really
|
|
sure you need the memory resource controller. Even when you enable
|
|
this, you can set "cgroup_disable=memory" at your boot option to
|
|
disable memory resource controller and you can avoid overheads
|
|
(but lose benefits of memory resource controller).
|
|
|
|
This config option also selects MM_OWNER config option, which
|
|
could in turn add some fork/exit overhead.
|
|
|
|
config KERNEL_MEMCG_SWAP
|
|
bool "Memory Resource Controller Swap Extension"
|
|
default n
|
|
depends on KERNEL_MEMCG
|
|
help
|
|
Add swap management feature to memory resource controller. When you
|
|
enable this, you can limit mem+swap usage per cgroup. In other words,
|
|
when you disable this, memory resource controller has no cares to
|
|
usage of swap...a process can exhaust all of the swap. This extension
|
|
is useful when you want to avoid exhaustion swap but this itself
|
|
adds more overheads and consumes memory for remembering information.
|
|
Especially if you use 32bit system or small memory system, please
|
|
be careful about enabling this. When memory resource controller
|
|
is disabled by boot option, this will be automatically disabled and
|
|
there will be no overhead from this. Even when you set this config=y,
|
|
if boot option "swapaccount=0" is set, swap will not be accounted.
|
|
Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
|
|
size is 4096bytes, 512k per 1Gbytes of swap.
|
|
|
|
config KERNEL_MEMCG_SWAP_ENABLED
|
|
bool "Memory Resource Controller Swap Extension enabled by default"
|
|
default n
|
|
depends on KERNEL_MEMCG_SWAP
|
|
help
|
|
Memory Resource Controller Swap Extension comes with its price in
|
|
a bigger memory consumption. General purpose distribution kernels
|
|
which want to enable the feature but keep it disabled by default
|
|
and let the user enable it by swapaccount boot command line
|
|
parameter should have this option unselected.
|
|
|
|
Those who want to have the feature enabled by default should
|
|
select this option (if, for some reason, they need to disable it,
|
|
then swapaccount=0 does the trick).
|
|
|
|
|
|
config KERNEL_MEMCG_KMEM
|
|
bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
|
|
default y if !SMALL_FLASH
|
|
depends on KERNEL_MEMCG
|
|
help
|
|
The Kernel Memory extension for Memory Resource Controller can limit
|
|
the amount of memory used by kernel objects in the system. Those are
|
|
fundamentally different from the entities handled by the standard
|
|
Memory Controller, which are page-based, and can be swapped. Users of
|
|
the kmem extension can use it to guarantee that no group of processes
|
|
will ever exhaust kernel resources alone.
|
|
|
|
config KERNEL_CGROUP_PERF
|
|
bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
|
|
select KERNEL_PERF_EVENTS
|
|
default n
|
|
help
|
|
This option extends the per-cpu mode to restrict monitoring to
|
|
threads which belong to the cgroup specified and run on the
|
|
designated cpu.
|
|
|
|
menuconfig KERNEL_CGROUP_SCHED
|
|
bool "Group CPU scheduler"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
This feature lets CPU scheduler recognize task groups and control CPU
|
|
bandwidth allocation to such task groups. It uses cgroups to group
|
|
tasks.
|
|
|
|
if KERNEL_CGROUP_SCHED
|
|
|
|
config KERNEL_FAIR_GROUP_SCHED
|
|
bool "Group scheduling for SCHED_OTHER"
|
|
default y if !SMALL_FLASH
|
|
|
|
config KERNEL_CFS_BANDWIDTH
|
|
bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
|
|
default n
|
|
depends on KERNEL_FAIR_GROUP_SCHED
|
|
help
|
|
This option allows users to define CPU bandwidth rates (limits) for
|
|
tasks running within the fair group scheduler. Groups with no limit
|
|
set are considered to be unconstrained and will run with no
|
|
restriction.
|
|
See tip/Documentation/scheduler/sched-bwc.txt for more information.
|
|
|
|
config KERNEL_RT_GROUP_SCHED
|
|
bool "Group scheduling for SCHED_RR/FIFO"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
This feature lets you explicitly allocate real CPU bandwidth
|
|
to task groups. If enabled, it will also make it impossible to
|
|
schedule realtime tasks for non-root users until you allocate
|
|
realtime bandwidth for them.
|
|
|
|
endif
|
|
|
|
config KERNEL_BLK_CGROUP
|
|
bool "Block IO controller"
|
|
default y
|
|
help
|
|
Generic block IO controller cgroup interface. This is the common
|
|
cgroup interface which should be used by various IO controlling
|
|
policies.
|
|
|
|
Currently, CFQ IO scheduler uses it to recognize task groups and
|
|
control disk bandwidth allocation (proportional time slice allocation)
|
|
to such task groups. It is also used by bio throttling logic in
|
|
block layer to implement upper limit in IO rates on a device.
|
|
|
|
This option only enables generic Block IO controller infrastructure.
|
|
One needs to also enable actual IO controlling logic/policy. For
|
|
enabling proportional weight division of disk bandwidth in CFQ, set
|
|
CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
|
|
CONFIG_BLK_DEV_THROTTLING=y.
|
|
|
|
if KERNEL_BLK_CGROUP
|
|
|
|
config KERNEL_CFQ_GROUP_IOSCHED
|
|
bool "Proportional weight of disk bandwidth in CFQ"
|
|
|
|
config KERNEL_BLK_DEV_THROTTLING
|
|
bool "Enable throttling policy"
|
|
default y if TARGET_bcm27xx
|
|
|
|
config KERNEL_BLK_DEV_THROTTLING_LOW
|
|
bool "Block throttling .low limit interface support (EXPERIMENTAL)"
|
|
depends on KERNEL_BLK_DEV_THROTTLING
|
|
endif
|
|
|
|
config KERNEL_DEBUG_BLK_CGROUP
|
|
bool "Enable Block IO controller debugging"
|
|
default n
|
|
depends on KERNEL_BLK_CGROUP
|
|
help
|
|
Enable some debugging help. Currently it exports additional stat
|
|
files in a cgroup which can be useful for debugging.
|
|
|
|
config KERNEL_NET_CLS_CGROUP
|
|
bool "Control Group Classifier"
|
|
default y
|
|
|
|
config KERNEL_CGROUP_NET_PRIO
|
|
bool "Network priority cgroup"
|
|
default y
|
|
|
|
endif
|
|
|
|
#
|
|
# Namespace support symbols
|
|
#
|
|
|
|
config KERNEL_NAMESPACES
|
|
bool "Enable kernel namespaces"
|
|
default y if !SMALL_FLASH
|
|
|
|
if KERNEL_NAMESPACES
|
|
|
|
config KERNEL_UTS_NS
|
|
bool "UTS namespace"
|
|
default y
|
|
help
|
|
In this namespace, tasks see different info provided
|
|
with the uname() system call.
|
|
|
|
config KERNEL_IPC_NS
|
|
bool "IPC namespace"
|
|
default y
|
|
help
|
|
In this namespace, tasks work with IPC ids which correspond to
|
|
different IPC objects in different namespaces.
|
|
|
|
config KERNEL_USER_NS
|
|
bool "User namespace (EXPERIMENTAL)"
|
|
default y
|
|
help
|
|
This allows containers, i.e. vservers, to use user namespaces
|
|
to provide different user info for different servers.
|
|
|
|
config KERNEL_PID_NS
|
|
bool "PID Namespaces"
|
|
default y
|
|
help
|
|
Support process id namespaces. This allows having multiple
|
|
processes with the same pid as long as they are in different
|
|
pid namespaces. This is a building block of containers.
|
|
|
|
config KERNEL_NET_NS
|
|
bool "Network namespace"
|
|
default y
|
|
help
|
|
Allow user space to create what appear to be multiple instances
|
|
of the network stack.
|
|
|
|
endif
|
|
|
|
config KERNEL_DEVPTS_MULTIPLE_INSTANCES
|
|
bool "Support multiple instances of devpts"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
Enable support for multiple instances of devpts filesystem.
|
|
If you want to have isolated PTY namespaces (eg: in containers),
|
|
say Y here. Otherwise, say N. If enabled, each mount of devpts
|
|
filesystem with the '-o newinstance' option will create an
|
|
independent PTY namespace.
|
|
|
|
config KERNEL_POSIX_MQUEUE
|
|
bool "POSIX Message Queues"
|
|
default y if !SMALL_FLASH
|
|
help
|
|
POSIX variant of message queues is a part of IPC. In POSIX message
|
|
queues every message has a priority which decides about succession
|
|
of receiving it by a process. If you want to compile and run
|
|
programs written e.g. for Solaris with use of its POSIX message
|
|
queues (functions mq_*) say Y here.
|
|
|
|
POSIX message queues are visible as a filesystem called 'mqueue'
|
|
and can be mounted somewhere if you want to do filesystem
|
|
operations on message queues.
|
|
|
|
|
|
config KERNEL_SECCOMP_FILTER
|
|
bool
|
|
default y if !SMALL_FLASH
|
|
|
|
config KERNEL_SECCOMP
|
|
bool "Enable seccomp support"
|
|
depends on !(TARGET_uml)
|
|
select KERNEL_SECCOMP_FILTER
|
|
default y if !SMALL_FLASH
|
|
help
|
|
Build kernel with support for seccomp.
|
|
|
|
#
|
|
# IPv4 configuration
|
|
#
|
|
|
|
config KERNEL_IP_MROUTE
|
|
bool "Enable IPv4 multicast routing"
|
|
default y
|
|
help
|
|
Multicast routing requires a multicast routing daemon in
|
|
addition to kernel support.
|
|
|
|
#
|
|
# IPv6 configuration
|
|
#
|
|
|
|
config KERNEL_IPV6
|
|
def_bool IPV6
|
|
|
|
if KERNEL_IPV6
|
|
|
|
config KERNEL_IPV6_MULTIPLE_TABLES
|
|
def_bool y
|
|
|
|
config KERNEL_IPV6_SUBTREES
|
|
def_bool y
|
|
|
|
config KERNEL_IPV6_MROUTE
|
|
bool "Enable IPv6 multicast routing"
|
|
default y
|
|
help
|
|
Multicast routing requires a multicast routing daemon in
|
|
addition to kernel support.
|
|
|
|
config KERNEL_IPV6_PIMSM_V2
|
|
def_bool n
|
|
|
|
endif
|
|
|
|
#
|
|
# NFS related symbols
|
|
#
|
|
config KERNEL_IP_PNP
|
|
bool "Compile the kernel with rootfs on NFS"
|
|
help
|
|
If you want to make your kernel boot off a NFS server as root
|
|
filesystem, select Y here.
|
|
|
|
if KERNEL_IP_PNP
|
|
|
|
config KERNEL_IP_PNP_DHCP
|
|
def_bool y
|
|
|
|
config KERNEL_IP_PNP_BOOTP
|
|
def_bool n
|
|
|
|
config KERNEL_IP_PNP_RARP
|
|
def_bool n
|
|
|
|
config KERNEL_NFS_FS
|
|
def_bool y
|
|
|
|
config KERNEL_NFS_V2
|
|
def_bool y
|
|
|
|
config KERNEL_NFS_V3
|
|
def_bool y
|
|
|
|
config KERNEL_ROOT_NFS
|
|
def_bool y
|
|
|
|
endif
|
|
|
|
menu "Filesystem ACL and attr support options"
|
|
config USE_FS_ACL_ATTR
|
|
bool "Use filesystem ACL and attr support by default"
|
|
default n
|
|
help
|
|
Make using ACLs (e.g. POSIX ACL, NFSv4 ACL) the default
|
|
for kernel and packages, except tmpfs, flash filesystems,
|
|
and old NFS. Also enable userspace extended attribute support
|
|
by default. (OpenWrt already has an expection it will be
|
|
present in the kernel).
|
|
|
|
config KERNEL_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL support"
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_BTRFS_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for BtrFS Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_EXT4_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for Ext4 Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_F2FS_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for F2FS Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default n
|
|
|
|
config KERNEL_JFFS2_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for JFFS2 Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default n
|
|
|
|
config KERNEL_TMPFS_POSIX_ACL
|
|
bool "Enable POSIX ACL for TMPFS Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default n
|
|
|
|
config KERNEL_CIFS_ACL
|
|
bool "Enable CIFS ACLs"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_HFS_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for HFS Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_HFSPLUS_FS_POSIX_ACL
|
|
bool "Enable POSIX ACL for HFS+ Filesystems"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_NFS_ACL_SUPPORT
|
|
bool "Enable ACLs for NFS"
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_NFS_V3_ACL_SUPPORT
|
|
bool "Enable ACLs for NFSv3"
|
|
default n
|
|
|
|
config KERNEL_NFSD_V2_ACL_SUPPORT
|
|
bool "Enable ACLs for NFSDv2"
|
|
default n
|
|
|
|
config KERNEL_NFSD_V3_ACL_SUPPORT
|
|
bool "Enable ACLs for NFSDv3"
|
|
default n
|
|
|
|
config KERNEL_REISER_FS_POSIX_ACL
|
|
bool "Enable POSIX ACLs for ReiserFS"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_XFS_POSIX_ACL
|
|
bool "Enable POSIX ACLs for XFS"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
config KERNEL_JFS_POSIX_ACL
|
|
bool "Enable POSIX ACLs for JFS"
|
|
select KERNEL_FS_POSIX_ACL
|
|
default y if USE_FS_ACL_ATTR
|
|
|
|
endmenu
|
|
|
|
config KERNEL_DEVMEM
|
|
bool "/dev/mem virtual device support"
|
|
help
|
|
Say Y here if you want to support the /dev/mem device.
|
|
The /dev/mem device is used to access areas of physical
|
|
memory.
|
|
|
|
config KERNEL_DEVKMEM
|
|
bool "/dev/kmem virtual device support"
|
|
help
|
|
Say Y here if you want to support the /dev/kmem device. The
|
|
/dev/kmem device is rarely used, but can be used for certain
|
|
kind of kernel debugging operations.
|
|
|
|
config KERNEL_SQUASHFS_FRAGMENT_CACHE_SIZE
|
|
int "Number of squashfs fragments cached"
|
|
default 2 if (SMALL_FLASH && !LOW_MEMORY_FOOTPRINT)
|
|
default 3
|
|
|
|
#
|
|
# compile optimiziation setting
|
|
#
|
|
choice
|
|
prompt "Compiler optimization level"
|
|
default KERNEL_CC_OPTIMIZE_FOR_SIZE if SMALL_FLASH
|
|
|
|
config KERNEL_CC_OPTIMIZE_FOR_PERFORMANCE
|
|
bool "Optimize for performance"
|
|
help
|
|
This is the default optimization level for the kernel, building
|
|
with the "-O2" compiler flag for best performance and most
|
|
helpful compile-time warnings.
|
|
|
|
config KERNEL_CC_OPTIMIZE_FOR_SIZE
|
|
bool "Optimize for size"
|
|
help
|
|
Enabling this option will pass "-Os" instead of "-O2" to
|
|
your compiler resulting in a smaller kernel.
|
|
|
|
endchoice
|