keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
unless you really know what this hack does.
+config STRIP_ASM_SYMS
+ bool "Strip assembler-generated symbols during link"
+ default n
+ help
+ Strip internal assembler-generated symbols during a link (symbols
+ that look like '.Lxxx') so they don't pollute the output of
+ get_wchan() and suchlike.
+
config UNUSED_SYMBOLS
bool "Enable unused/obsolete exported symbols"
default y if X86
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
+ # It will be enabled when we are down to a reasonable number
# of section mismatch warnings (< 10 for an allyesconfig build)
help
The section mismatch analysis checks if there are illegal
config DETECT_HUNG_TASK
bool "Detect Hung Tasks"
depends on DEBUG_KERNEL
- default y
+ default DETECT_SOFTLOCKUP
help
Say Y here to enable the kernel to detect "hung tasks",
which are bugs that cause the task to be stuck in
timer routines to track the life time of timer objects and
validate the timer operations.
+config DEBUG_OBJECTS_WORK
+ bool "Debug work objects"
+ depends on DEBUG_OBJECTS
+ help
+ If you say Y here, additional code will be inserted into the
+ work queue routines to track the life time of work objects and
+ validate the work operations.
+
config DEBUG_OBJECTS_ENABLE_DEFAULT
int "debug_objects bootup default value (0-1)"
range 0 1
config DEBUG_SLAB
bool "Debug slab memory allocations"
- depends on DEBUG_KERNEL && SLAB
+ depends on DEBUG_KERNEL && SLAB && !KMEMCHECK
help
Say Y here to have the kernel do limited verification on memory
allocation as well as poisoning memory on free to catch use of freed
config SLUB_DEBUG_ON
bool "SLUB debugging on by default"
- depends on SLUB && SLUB_DEBUG
+ depends on SLUB && SLUB_DEBUG && !KMEMCHECK
default n
help
Boot with debugging on by default. SLUB boots by default with
out which slabs are relevant to a particular load.
Try running: slabinfo -DA
+config DEBUG_KMEMLEAK
+ bool "Kernel memory leak detector"
+ depends on DEBUG_KERNEL && EXPERIMENTAL && !MEMORY_HOTPLUG && \
+ (X86 || ARM || PPC || S390 || SUPERH)
+
+ select DEBUG_FS if SYSFS
+ select STACKTRACE if STACKTRACE_SUPPORT
+ select KALLSYMS
+ select CRC32
+ help
+ Say Y here if you want to enable the memory leak
+ detector. The memory allocation/freeing is traced in a way
+ similar to the Boehm's conservative garbage collector, the
+ difference being that the orphan objects are not freed but
+ only shown in /sys/kernel/debug/kmemleak. Enabling this
+ feature will introduce an overhead to memory
+ allocations. See Documentation/kmemleak.txt for more
+ details.
+
+ Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances
+ of finding leaks due to the slab objects poisoning.
+
+ In order to access the kmemleak file, debugfs needs to be
+ mounted (usually at /sys/kernel/debug).
+
+config DEBUG_KMEMLEAK_EARLY_LOG_SIZE
+ int "Maximum kmemleak early log entries"
+ depends on DEBUG_KMEMLEAK
+ range 200 40000
+ default 400
+ help
+ Kmemleak must track all the memory allocations to avoid
+ reporting false positives. Since memory may be allocated or
+ freed before kmemleak is initialised, an early log buffer is
+ used to store these actions. If kmemleak reports "early log
+ buffer exceeded", please increase this value.
+
+config DEBUG_KMEMLEAK_TEST
+ tristate "Simple test for the kernel memory leak detector"
+ depends on DEBUG_KMEMLEAK
+ help
+ Say Y or M here to build a test for the kernel memory leak
+ detector. This option enables a module that explicitly leaks
+ memory.
+
+ If unsure, say N.
+
config DEBUG_PREEMPT
bool "Debug preemptible kernel"
- depends on DEBUG_KERNEL && PREEMPT && (TRACE_IRQFLAGS_SUPPORT || PPC64)
+ depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT
default y
help
If you say Y here then the kernel will use a debug variant of the
For more details, see Documentation/lockdep-design.txt.
+config PROVE_RCU
+ bool "RCU debugging: prove RCU correctness"
+ depends on PROVE_LOCKING
+ default n
+ help
+ This feature enables lockdep extensions that check for correct
+ use of RCU APIs. This is currently under development. Say Y
+ if you want to debug RCU usage or help work on the PROVE_RCU
+ feature.
+
+ Say N if you are unsure.
+
config LOCKDEP
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
select STACKTRACE
- select FRAME_POINTER if !X86 && !MIPS && !PPC
+ select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390
select KALLSYMS
select KALLSYMS_ALL
depends on BUG
depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \
FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300
- default !EMBEDDED
+ default y
help
Say Y here to make BUG() panics output the file name and line number
of the BUG call as well as the EIP and oops trace. This aids
This is a relatively cheap check but if you care about maximum
performance, say N.
+config DEBUG_CREDENTIALS
+ bool "Debug credential management"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on some debug checking for credential
+ management. The additional code keeps track of the number of
+ pointers from task_structs to any given cred struct, and checks to
+ see that this number never exceeds the usage count of the cred
+ struct.
+
+ Furthermore, if SELinux is enabled, this also checks that the
+ security pointer in the cred struct is never seen to be invalid.
+
+ If unsure, say N.
+
+#
+# Select this config option from the architecture Kconfig, if it
+# it is preferred to always offer frame pointers as a config
+# option on the architecture (regardless of KERNEL_DEBUG):
+#
+config ARCH_WANT_FRAME_POINTERS
+ bool
+ help
+
config FRAME_POINTER
bool "Compile the kernel with frame pointers"
depends on DEBUG_KERNEL && \
- (CRIS || M68K || M68KNOMMU || FRV || UML || S390 || \
+ (CRIS || M68K || M68KNOMMU || FRV || UML || \
AVR32 || SUPERH || BLACKFIN || MN10300) || \
ARCH_WANT_FRAME_POINTERS
default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS
config RCU_CPU_STALL_DETECTOR
bool "Check for stalled CPUs delaying RCU grace periods"
- depends on CLASSIC_RCU
- default n
+ depends on TREE_RCU || TREE_PREEMPT_RCU
+ default y
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 want to disable such checks.
- Say N if you are unsure.
+ Say Y if you are unsure.
-config RCU_CPU_STALL_DETECTOR
- bool "Check for stalled CPUs delaying RCU grace periods"
- depends on CLASSIC_RCU || TREE_RCU
+config RCU_CPU_STALL_VERBOSE
+ bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR"
+ depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_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.
+ This option causes RCU to printk detailed per-task information
+ for any tasks that are stalling the current RCU grace period.
Say N if you are unsure.
+ Say Y if you want to enable such checks.
+
config KPROBES_SANITY_TEST
bool "Kprobes sanity tests"
depends on DEBUG_KERNEL
Say N if you are unsure.
+config DEBUG_FORCE_WEAK_PER_CPU
+ bool "Force weak per-cpu definitions"
+ depends on DEBUG_KERNEL
+ help
+ s390 and alpha require percpu variables in modules to be
+ defined weak to work around addressing range issue which
+ puts the following two restrictions on percpu variable
+ definitions.
+
+ 1. percpu symbols must be unique whether static or not
+ 2. percpu variables can't be defined inside a function
+
+ To ensure that generic code follows the above rules, this
+ option forces all percpu variables to be defined as weak.
+
config LKDTM
tristate "Linux Kernel Dump Test Tool Module"
- depends on DEBUG_KERNEL
- depends on KPROBES
+ depends on DEBUG_FS
depends on BLOCK
default n
help
called lkdtm.
Documentation on how to use the module can be found in
- drivers/misc/lkdtm.c
+ Documentation/fault-injection/provoke-crashes.txt
config FAULT_INJECTION
bool "Fault-injection framework"
depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT
depends on !X86_64
select STACKTRACE
- select FRAME_POINTER if !PPC
+ select FRAME_POINTER if !PPC && !S390
help
Provide stacktrace filter for fault-injection capabilities
config LATENCYTOP
bool "Latency measuring infrastructure"
- select FRAME_POINTER if !MIPS && !PPC
+ select FRAME_POINTER if !MIPS && !PPC && !S390
select KALLSYMS
select KALLSYMS_ALL
select STACKTRACE
config SYSCTL_SYSCALL_CHECK
bool "Sysctl checks"
- depends on SYSCTL_SYSCALL
+ depends on SYSCTL
---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 mm/Kconfig.debug
source kernel/trace/Kconfig
config PROVIDE_OHCI1394_DMA_INIT
If unsure, say N.
-menuconfig BUILD_DOCSRC
+config BUILD_DOCSRC
bool "Build targets in Documentation/ tree"
depends on HEADERS_CHECK
help
Say N if you are unsure.
-config DYNAMIC_PRINTK_DEBUG
- bool "Enable dynamic printk() call support"
+config DYNAMIC_DEBUG
+ bool "Enable dynamic printk() support"
default n
depends on PRINTK
- select PRINTK_DEBUG
+ depends on DEBUG_FS
help
Compiles debug level messages into the kernel, which would not
otherwise be available at runtime. These messages can then be
- enabled/disabled on a per module basis. This mechanism implicitly
- enables all pr_debug() and dev_dbg() calls. The impact of this
- compile option is a larger kernel text size of about 2%.
+ enabled/disabled based on various levels of scope - per source file,
+ function, module, format string, and line number. This mechanism
+ implicitly enables all pr_debug() and dev_dbg() calls. The impact of
+ this compile option is a larger kernel text size of about 2%.
Usage:
- Dynamic debugging is controlled by the debugfs file,
- dynamic_printk/modules. This file contains a list of the modules that
- can be enabled. The format of the file is the module name, followed
- by a set of flags that can be enabled. The first flag is always the
- 'enabled' flag. For example:
+ Dynamic debugging is controlled via the 'dynamic_debug/ddebug' file,
+ which is contained in the 'debugfs' filesystem. Thus, the debugfs
+ filesystem must first be mounted before making use of this feature.
+ We refer the control file as: <debugfs>/dynamic_debug/ddebug. This
+ file contains a list of the debug statements that can be enabled. The
+ format for each line of the file is:
- <module_name> <enabled=0/1>
- .
- .
- .
+ filename:lineno [module]function flags format
- <module_name> : Name of the module in which the debug call resides
- <enabled=0/1> : whether the messages are enabled or not
+ filename : source file of the debug statement
+ lineno : line number of the debug statement
+ module : module that contains the debug statement
+ function : function that contains the debug statement
+ flags : 'p' means the line is turned 'on' for printing
+ format : the format used for the debug statement
From a live system:
- snd_hda_intel enabled=0
- fixup enabled=0
- driver enabled=0
+ nullarbor:~ # cat <debugfs>/dynamic_debug/ddebug
+ # filename:lineno [module]function flags format
+ fs/aio.c:222 [aio]__put_ioctx - "__put_ioctx:\040freeing\040%p\012"
+ fs/aio.c:248 [aio]ioctx_alloc - "ENOMEM:\040nr_events\040too\040high\012"
+ fs/aio.c:1770 [aio]sys_io_cancel - "calling\040cancel\012"
- Enable a module:
+ Example usage:
- $echo "set enabled=1 <module_name>" > dynamic_printk/modules
+ // enable the message at line 1603 of file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
+ <debugfs>/dynamic_debug/ddebug
- Disable a module:
+ // enable all the messages in file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c +p' >
+ <debugfs>/dynamic_debug/ddebug
- $echo "set enabled=0 <module_name>" > dynamic_printk/modules
+ // enable all the messages in the NFS server module
+ nullarbor:~ # echo -n 'module nfsd +p' >
+ <debugfs>/dynamic_debug/ddebug
- Enable all modules:
+ // enable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process +p' >
+ <debugfs>/dynamic_debug/ddebug
- $echo "set enabled=1 all" > dynamic_printk/modules
+ // disable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process -p' >
+ <debugfs>/dynamic_debug/ddebug
- Disable all modules:
+ See Documentation/dynamic-debug-howto.txt for additional information.
- $echo "set enabled=0 all" > dynamic_printk/modules
-
- Finally, passing "dynamic_printk" at the command line enables
- debugging for all modules. This mode can be turned off via the above
- disable command.
+config DMA_API_DEBUG
+ bool "Enable debugging of DMA-API usage"
+ depends on HAVE_DMA_API_DEBUG
+ help
+ Enable this option to debug the use of the DMA API by device drivers.
+ With this option you will be able to detect common bugs in device
+ drivers like double-freeing of DMA mappings or freeing mappings that
+ were never allocated.
+ This option causes a performance degredation. Use only if you want
+ to debug device drivers. If unsure, say N.
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
+
+source "lib/Kconfig.kmemcheck"
Code Review / linux-2.6.git / blobdiff