operations. This is useful for identifying long delays
in kernel startup.
+config ENABLE_WARN_DEPRECATED
+ bool "Enable __deprecated logic"
+ default y
+ help
+ Enable the __deprecated logic in the kernel build.
+ Disable this to suppress the "warning: 'foo' is deprecated
+ (declared at kernel/power/somefile.c:1234)" messages.
+
config ENABLE_MUST_CHECK
bool "Enable __must_check logic"
default y
suppress the "warning: ignoring return value of 'foo', declared with
attribute warn_unused_result" messages.
+config FRAME_WARN
+ int "Warn for stack frames larger than (needs gcc 4.4)"
+ range 0 8192
+ default 1024 if !64BIT
+ default 2048 if 64BIT
+ help
+ Tell gcc to warn at build time for stack frames larger than this.
+ Setting this too low will cause a lot of warnings.
+ Setting it to 0 disables the warning.
+ Requires gcc 4.4
+
config MAGIC_SYSRQ
bool "Magic SysRq key"
depends on !UML
debugging files into. Enable this option to be able to read and
write to these files.
+ For detailed documentation on the debugfs API, see
+ Documentation/DocBook/filesystems.
+
If unsure, say N.
config HEADERS_CHECK
exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in
your build tree), to make sure they're suitable.
+config DEBUG_SECTION_MISMATCH
+ bool "Enable full Section mismatch analysis"
+ depends on UNDEFINED
+ # This option is on purpose disabled for now.
+ # It will be enabled when we are down to a resonable number
+ # of section mismatch warnings (< 10 for an allyesconfig build)
+ help
+ The section mismatch analysis checks if there are illegal
+ references from one section to another section.
+ Linux will during link or during runtime drop some sections
+ and any use of code/data previously in these sections will
+ most likely result in an oops.
+ In the code functions and variables are annotated with
+ __init, __devinit etc. (see full list in include/linux/init.h)
+ which results in the code/data being placed in specific sections.
+ The section mismatch analysis is always done after a full
+ kernel build but enabling this option will in addition
+ do the following:
+ - Add the option -fno-inline-functions-called-once to gcc
+ When inlining a function annotated __init in a non-init
+ function we would lose the section information and thus
+ the analysis would not catch the illegal reference.
+ This option tells gcc to inline less but will also
+ result in a larger kernel.
+ - Run the section mismatch analysis for each module/built-in.o
+ When we run the section mismatch analysis on vmlinux.o we
+ lose valueble information about where the mismatch was
+ introduced.
+ Running the analysis for each module/built-in.o file
+ will tell where the mismatch happens much closer to the
+ source. The drawback is that we will report the same
+ mismatch at least twice.
+ - Enable verbose reporting from modpost to help solving
+ the section mismatches reported.
+
config DEBUG_KERNEL
bool "Kernel debugging"
help
help
Say Y here to enable the kernel to detect "soft lockups",
which are bugs that cause the kernel to loop in kernel
- mode for more than 10 seconds, without giving other tasks a
+ mode for more than 60 seconds, without giving other tasks a
chance to run.
When a soft-lockup is detected, the kernel will print the
can be detected via the NMI-watchdog, on platforms that
support it.)
+config BOOTPARAM_SOFTLOCKUP_PANIC
+ bool "Panic (Reboot) On Soft Lockups"
+ depends on DETECT_SOFTLOCKUP
+ help
+ Say Y here to enable the kernel to panic on "soft lockups",
+ which are bugs that cause the kernel to loop in kernel
+ mode for more than 60 seconds, without giving other tasks a
+ chance to run.
+
+ The panic can be used in combination with panic_timeout,
+ to cause the system to reboot automatically after a
+ lockup has been detected. This feature is useful for
+ high-availability systems that have uptime guarantees and
+ where a lockup must be resolved ASAP.
+
+ Say N if unsure.
+
+config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE
+ int
+ depends on DETECT_SOFTLOCKUP
+ range 0 1
+ default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC
+ default 1 if BOOTPARAM_SOFTLOCKUP_PANIC
+
config SCHED_DEBUG
bool "Collect scheduler debugging info"
depends on DEBUG_KERNEL && PROC_FS
(it defaults to deactivated on bootup and will only be activated
if some application like powertop activates it explicitly).
+config DEBUG_OBJECTS
+ bool "Debug object operations"
+ depends on DEBUG_KERNEL
+ help
+ If you say Y here, additional code will be inserted into the
+ kernel to track the life time of various objects and validate
+ the operations on those objects.
+
+config DEBUG_OBJECTS_SELFTEST
+ bool "Debug objects selftest"
+ depends on DEBUG_OBJECTS
+ help
+ This enables the selftest of the object debug code.
+
+config DEBUG_OBJECTS_FREE
+ bool "Debug objects in freed memory"
+ depends on DEBUG_OBJECTS
+ help
+ This enables checks whether a k/v free operation frees an area
+ which contains an object which has not been deactivated
+ properly. This can make kmalloc/kfree-intensive workloads
+ much slower.
+
+config DEBUG_OBJECTS_TIMERS
+ bool "Debug timer objects"
+ depends on DEBUG_OBJECTS
+ help
+ If you say Y here, additional code will be inserted into the
+ timer routines to track the life time of timer objects and
+ validate the timer operations.
+
config DEBUG_SLAB
bool "Debug slab memory allocations"
depends on DEBUG_KERNEL && SLAB
off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying
"slub_debug=-".
+config SLUB_STATS
+ default n
+ bool "Enable SLUB performance statistics"
+ depends on SLUB && SLUB_DEBUG && SYSFS
+ help
+ SLUB statistics are useful to debug SLUBs allocation behavior in
+ order find ways to optimize the allocator. This should never be
+ enabled for production use since keeping statistics slows down
+ the allocator by a few percentage points. The slabinfo command
+ supports the determination of the most active slabs to figure
+ out which slabs are relevant to a particular load.
+ Try running: slabinfo -DA
+
config DEBUG_PREEMPT
bool "Debug preemptible kernel"
depends on DEBUG_KERNEL && PREEMPT && (TRACE_IRQFLAGS_SUPPORT || PPC64)
This feature allows mutex semantics violations to be detected and
reported.
-config DEBUG_SEMAPHORE
- bool "Semaphore debugging"
- depends on DEBUG_KERNEL
- depends on ALPHA || FRV
- default n
- help
- If you say Y here then semaphore processing will issue lots of
- verbose debugging messages. If you suspect a semaphore problem or a
- kernel hacker asks for this option then say Y. Otherwise say N.
-
config DEBUG_LOCK_ALLOC
bool "Lock debugging: detect incorrect freeing of live locks"
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
select STACKTRACE
- select FRAME_POINTER if !X86 && !MIPS
+ select FRAME_POINTER if !X86 && !MIPS && !PPC
select KALLSYMS
select KALLSYMS_ALL
config STACKTRACE
bool
- depends on DEBUG_KERNEL
depends on STACKTRACE_SUPPORT
config DEBUG_KOBJECT
config DEBUG_BUGVERBOSE
bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EMBEDDED
depends on BUG
- depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || FRV || SUPERH || GENERIC_BUG || BFIN
+ depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \
+ FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300
default !EMBEDDED
help
Say Y here to make BUG() panics output the file name and line number
If unsure, say N.
+config DEBUG_WRITECOUNT
+ bool "Debug filesystem writers count"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to catch wrong use of the writers count in struct
+ vfsmount. This will increase the size of each file struct by
+ 32 bits.
+
+ If unsure, say N.
+
+config DEBUG_MEMORY_INIT
+ bool "Debug memory initialisation" if EMBEDDED
+ default !EMBEDDED
+ help
+ Enable this for additional checks during memory initialisation.
+ The sanity checks verify aspects of the VM such as the memory model
+ and other information provided by the architecture. Verbose
+ information will be printed at KERN_DEBUG loglevel depending
+ on the mminit_loglevel= command-line option.
+
+ If unsure, say Y
+
config DEBUG_LIST
bool "Debug linked list manipulation"
depends on DEBUG_KERNEL
If unsure, say N.
+config DEBUG_SG
+ bool "Debug SG table operations"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on checks on scatter-gather tables. This can
+ help find problems with drivers that do not properly initialize
+ their sg tables.
+
+ If unsure, say N.
+
config FRAME_POINTER
bool "Compile the kernel with frame pointers"
- depends on DEBUG_KERNEL && (X86 || CRIS || M68K || M68KNOMMU || FRV || UML || S390 || AVR32 || SUPERH || BFIN)
+ depends on DEBUG_KERNEL && \
+ (X86 || CRIS || M68K || M68KNOMMU || FRV || UML || S390 || \
+ AVR32 || SUPERH || BLACKFIN || MN10300)
default y if DEBUG_INFO && UML
help
If you say Y here the resulting kernel image will be slightly larger
some architectures or if you use external debuggers.
If you don't debug the kernel, you can say N.
-config FORCED_INLINING
- bool "Force gcc to inline functions marked 'inline'"
- depends on DEBUG_KERNEL
- default y
- help
- This option determines if the kernel forces gcc to inline the functions
- developers have marked 'inline'. Doing so takes away freedom from gcc to
- do what it thinks is best, which is desirable for the gcc 3.x series of
- compilers. The gcc 4.x series have a rewritten inlining algorithm and
- disabling this option will generate a smaller kernel there. Hopefully
- this algorithm is so good that allowing gcc4 to make the decision can
- become the default in the future, until then this option is there to
- test gcc for this.
-
config BOOT_PRINTK_DELAY
bool "Delay each boot printk message by N milliseconds"
depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY
config RCU_TORTURE_TEST
tristate "torture tests for RCU"
depends on DEBUG_KERNEL
- depends on m
default n
help
This option provides a kernel module that runs torture tests
on the RCU infrastructure. The kernel module may be built
after the fact on the running kernel to be tested, if desired.
+ Say Y here if you want RCU torture tests to be built into
+ the kernel.
Say M if you want the RCU torture tests to build as a module.
Say N if you are unsure.
+config RCU_TORTURE_TEST_RUNNABLE
+ bool "torture tests for RCU runnable by default"
+ depends on RCU_TORTURE_TEST = y
+ default n
+ help
+ This option provides a way to build the RCU torture tests
+ directly into the kernel without them starting up at boot
+ time. You can use /proc/sys/kernel/rcutorture_runnable
+ to manually override this setting. This /proc file is
+ available only when the RCU torture tests have been built
+ into the kernel.
+
+ Say Y here if you want the RCU torture tests to start during
+ boot (you probably don't).
+ Say N here if you want the RCU torture tests to start only
+ after being manually enabled via /proc.
+
+config RCU_CPU_STALL_DETECTOR
+ bool "Check for stalled CPUs delaying RCU grace periods"
+ depends on CLASSIC_RCU
+ default n
+ help
+ This option causes RCU to printk information on which
+ CPUs are delaying the current grace period, but only when
+ the grace period extends for excessive time periods.
+
+ Say Y if you want RCU to perform such checks.
+
+ Say N if you are unsure.
+
+config KPROBES_SANITY_TEST
+ bool "Kprobes sanity tests"
+ depends on DEBUG_KERNEL
+ depends on KPROBES
+ default n
+ help
+ This option provides for testing basic kprobes functionality on
+ boot. A sample kprobe, jprobe and kretprobe are inserted and
+ verified for functionality.
+
+ Say N if you are unsure.
+
+config BACKTRACE_SELF_TEST
+ tristate "Self test for the backtrace code"
+ depends on DEBUG_KERNEL
+ default n
+ help
+ This option provides a kernel module that can be used to test
+ the kernel stack backtrace code. This option is not useful
+ for distributions or general kernels, but only for kernel
+ developers working on architecture code.
+
+ Note that if you want to also test saved backtraces, you will
+ have to enable STACKTRACE as well.
+
+ Say N if you are unsure.
+
+config DEBUG_BLOCK_EXT_DEVT
+ bool "Force extended block device numbers and spread them"
+ depends on DEBUG_KERNEL
+ depends on BLOCK
+ default n
+ help
+ Conventionally, block device numbers are allocated from
+ predetermined contiguous area. However, extended block area
+ may introduce non-contiguous block device numbers. This
+ option forces most block device numbers to be allocated from
+ the extended space and spreads them to discover kernel or
+ userland code paths which assume predetermined contiguous
+ device number allocation.
+
+ Note that turning on this debug option shuffles all the
+ device numbers for all IDE and SCSI devices including libata
+ ones, so root partition specified using device number
+ directly (via rdev or root=MAJ:MIN) won't work anymore.
+ Textual device names (root=/dev/sdXn) will continue to work.
+
+ Say N if you are unsure.
+
config LKDTM
tristate "Linux Kernel Dump Test Tool Module"
depends on DEBUG_KERNEL
depends on KPROBES
+ depends on BLOCK
default n
help
This module enables testing of the different dumping mechanisms by
config FAIL_MAKE_REQUEST
bool "Fault-injection capability for disk IO"
- depends on FAULT_INJECTION
+ depends on FAULT_INJECTION && BLOCK
help
Provide fault-injection capability for disk IO.
+config FAIL_IO_TIMEOUT
+ bool "Faul-injection capability for faking disk interrupts"
+ depends on FAULT_INJECTION && BLOCK
+ help
+ Provide fault-injection capability on end IO handling. This
+ will make the block layer "forget" an interrupt as configured,
+ thus exercising the error handling.
+
+ Only works with drivers that use the generic timeout handling,
+ for others it wont do anything.
+
config FAULT_INJECTION_DEBUG_FS
bool "Debugfs entries for fault-injection capabilities"
depends on FAULT_INJECTION && SYSFS && DEBUG_FS
depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT
depends on !X86_64
select STACKTRACE
- select FRAME_POINTER
+ select FRAME_POINTER if !PPC
help
Provide stacktrace filter for fault-injection capabilities
+config LATENCYTOP
+ bool "Latency measuring infrastructure"
+ select FRAME_POINTER if !MIPS && !PPC
+ select KALLSYMS
+ select KALLSYMS_ALL
+ select STACKTRACE
+ select SCHEDSTATS
+ select SCHED_DEBUG
+ depends on HAVE_LATENCYTOP_SUPPORT
+ help
+ Enable this option if you want to use the LatencyTOP tool
+ to find out which userspace is blocking on what kernel operations.
+
+config SYSCTL_SYSCALL_CHECK
+ bool "Sysctl checks"
+ depends on SYSCTL_SYSCALL
+ ---help---
+ sys_sysctl uses binary paths that have been found challenging
+ to properly maintain and use. This enables checks that help
+ you to keep things correct.
+
+source kernel/trace/Kconfig
+
+config PROVIDE_OHCI1394_DMA_INIT
+ bool "Remote debugging over FireWire early on boot"
+ depends on PCI && X86
+ help
+ If you want to debug problems which hang or crash the kernel early
+ on boot and the crashing machine has a FireWire port, you can use
+ this feature to remotely access the memory of the crashed machine
+ over FireWire. This employs remote DMA as part of the OHCI1394
+ specification which is now the standard for FireWire controllers.
+
+ With remote DMA, you can monitor the printk buffer remotely using
+ firescope and access all memory below 4GB using fireproxy from gdb.
+ Even controlling a kernel debugger is possible using remote DMA.
+
+ Usage:
+
+ If ohci1394_dma=early is used as boot parameter, it will initialize
+ all OHCI1394 controllers which are found in the PCI config space.
+
+ As all changes to the FireWire bus such as enabling and disabling
+ devices cause a bus reset and thereby disable remote DMA for all
+ devices, be sure to have the cable plugged and FireWire enabled on
+ the debugging host before booting the debug target for debugging.
+
+ This code (~1k) is freed after boot. By then, the firewire stack
+ in charge of the OHCI-1394 controllers should be used instead.
+
+ See Documentation/debugging-via-ohci1394.txt for more information.
+
+config FIREWIRE_OHCI_REMOTE_DMA
+ bool "Remote debugging over FireWire with firewire-ohci"
+ depends on FIREWIRE_OHCI
+ help
+ This option lets you use the FireWire bus for remote debugging
+ with help of the firewire-ohci driver. It enables unfiltered
+ remote DMA in firewire-ohci.
+ See Documentation/debugging-via-ohci1394.txt for more information.
+
+ If unsure, say N.
+
+menuconfig BUILD_DOCSRC
+ bool "Build targets in Documentation/ tree"
+ depends on HEADERS_CHECK
+ help
+ This option attempts to build objects from the source files in the
+ kernel Documentation/ tree.
+
+ Say N if you are unsure.
+
source "samples/Kconfig"
+
+source "lib/Kconfig.kgdb"