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-rw-r--r--lib/Kconfig.debug1076
1 files changed, 561 insertions, 515 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 7154f79..88c8d98 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1,3 +1,4 @@
+menu "printk and dmesg options"
config PRINTK_TIME
bool "Show timing information on printks"
@@ -25,6 +26,123 @@ config DEFAULT_MESSAGE_LOGLEVEL
that are auditing their logs closely may want to set it to a lower
priority.
+config BOOT_PRINTK_DELAY
+ bool "Delay each boot printk message by N milliseconds"
+ depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY
+ help
+ This build option allows you to read kernel boot messages
+ by inserting a short delay after each one. The delay is
+ specified in milliseconds on the kernel command line,
+ using "boot_delay=N".
+
+ It is likely that you would also need to use "lpj=M" to preset
+ the "loops per jiffie" value.
+ See a previous boot log for the "lpj" value to use for your
+ system, and then set "lpj=M" before setting "boot_delay=N".
+ NOTE: Using this option may adversely affect SMP systems.
+ I.e., processors other than the first one may not boot up.
+ BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect
+ what it believes to be lockup conditions.
+
+config DYNAMIC_DEBUG
+ bool "Enable dynamic printk() support"
+ default n
+ depends on PRINTK
+ 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 based on various levels of scope - per source file,
+ function, module, format string, and line number. This mechanism
+ implicitly compiles in all pr_debug() and dev_dbg() calls, which
+ enlarges the kernel text size by about 2%.
+
+ If a source file is compiled with DEBUG flag set, any
+ pr_debug() calls in it are enabled by default, but can be
+ disabled at runtime as below. Note that DEBUG flag is
+ turned on by many CONFIG_*DEBUG* options.
+
+ Usage:
+
+ Dynamic debugging is controlled via the 'dynamic_debug/control' 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/control. This
+ file contains a list of the debug statements that can be enabled. The
+ format for each line of the file is:
+
+ filename:lineno [module]function flags format
+
+ 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:
+
+ nullarbor:~ # cat <debugfs>/dynamic_debug/control
+ # 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"
+
+ Example usage:
+
+ // enable the message at line 1603 of file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
+ <debugfs>/dynamic_debug/control
+
+ // enable all the messages in file svcsock.c
+ nullarbor:~ # echo -n 'file svcsock.c +p' >
+ <debugfs>/dynamic_debug/control
+
+ // enable all the messages in the NFS server module
+ nullarbor:~ # echo -n 'module nfsd +p' >
+ <debugfs>/dynamic_debug/control
+
+ // enable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process +p' >
+ <debugfs>/dynamic_debug/control
+
+ // disable all 12 messages in the function svc_process()
+ nullarbor:~ # echo -n 'func svc_process -p' >
+ <debugfs>/dynamic_debug/control
+
+ See Documentation/dynamic-debug-howto.txt for additional information.
+
+endmenu # "printk and dmesg options"
+
+menu "Compile-time checks and compiler options"
+
+config DEBUG_INFO
+ bool "Compile the kernel with debug info"
+ depends on DEBUG_KERNEL
+ help
+ If you say Y here the resulting kernel image will include
+ debugging info resulting in a larger kernel image.
+ This adds debug symbols to the kernel and modules (gcc -g), and
+ is needed if you intend to use kernel crashdump or binary object
+ tools like crash, kgdb, LKCD, gdb, etc on the kernel.
+ Say Y here only if you plan to debug the kernel.
+
+ If unsure, say N.
+
+config DEBUG_INFO_REDUCED
+ bool "Reduce debugging information"
+ depends on DEBUG_INFO
+ help
+ If you say Y here gcc is instructed to generate less debugging
+ information for structure types. This means that tools that
+ need full debugging information (like kgdb or systemtap) won't
+ be happy. But if you merely need debugging information to
+ resolve line numbers there is no loss. Advantage is that
+ build directory object sizes shrink dramatically over a full
+ DEBUG_INFO build and compile times are reduced too.
+ Only works with newer gcc versions.
+
config ENABLE_WARN_DEPRECATED
bool "Enable __deprecated logic"
default y
@@ -52,20 +170,6 @@ config FRAME_WARN
Setting it to 0 disables the warning.
Requires gcc 4.4
-config MAGIC_SYSRQ
- bool "Magic SysRq key"
- depends on !UML
- help
- If you say Y here, you will have some control over the system even
- if the system crashes for example during kernel debugging (e.g., you
- will be able to flush the buffer cache to disk, reboot the system
- immediately or dump some status information). This is accomplished
- by pressing various keys while holding SysRq (Alt+PrintScreen). It
- also works on a serial console (on PC hardware at least), if you
- send a BREAK and then within 5 seconds a command keypress. The
- 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
@@ -156,12 +260,341 @@ config DEBUG_SECTION_MISMATCH
- Enable verbose reporting from modpost in order to help resolve
the section mismatches that are reported.
+#
+# Select this config option from the architecture Kconfig, if 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 || FRV || UML || \
+ AVR32 || SUPERH || BLACKFIN || MN10300 || METAG) || \
+ ARCH_WANT_FRAME_POINTERS
+ default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS
+ help
+ If you say Y here the resulting kernel image will be slightly
+ larger and slower, but it gives very useful debugging information
+ in case of kernel bugs. (precise oopses/stacktraces/warnings)
+
+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.
+
+endmenu # "Compiler options"
+
+config MAGIC_SYSRQ
+ bool "Magic SysRq key"
+ depends on !UML
+ help
+ If you say Y here, you will have some control over the system even
+ if the system crashes for example during kernel debugging (e.g., you
+ will be able to flush the buffer cache to disk, reboot the system
+ immediately or dump some status information). This is accomplished
+ by pressing various keys while holding SysRq (Alt+PrintScreen). It
+ also works on a serial console (on PC hardware at least), if you
+ send a BREAK and then within 5 seconds a command keypress. The
+ keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
+ unless you really know what this hack does.
+
config DEBUG_KERNEL
bool "Kernel debugging"
help
Say Y here if you are developing drivers or trying to debug and
identify kernel problems.
+menu "Memory Debugging"
+
+source mm/Kconfig.debug
+
+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_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_RCU_HEAD
+ bool "Debug RCU callbacks objects"
+ depends on DEBUG_OBJECTS
+ help
+ Enable this to turn on debugging of RCU list heads (call_rcu() usage).
+
+config DEBUG_OBJECTS_PERCPU_COUNTER
+ bool "Debug percpu counter objects"
+ depends on DEBUG_OBJECTS
+ help
+ If you say Y here, additional code will be inserted into the
+ percpu counter routines to track the life time of percpu counter
+ objects and validate the percpu counter operations.
+
+config DEBUG_OBJECTS_ENABLE_DEFAULT
+ int "debug_objects bootup default value (0-1)"
+ range 0 1
+ default "1"
+ depends on DEBUG_OBJECTS
+ help
+ Debug objects boot parameter default value
+
+config DEBUG_SLAB
+ bool "Debug slab memory allocations"
+ 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
+ memory. This can make kmalloc/kfree-intensive workloads much slower.
+
+config DEBUG_SLAB_LEAK
+ bool "Memory leak debugging"
+ depends on DEBUG_SLAB
+
+config SLUB_DEBUG_ON
+ bool "SLUB debugging on by default"
+ depends on SLUB && SLUB_DEBUG && !KMEMCHECK
+ default n
+ help
+ Boot with debugging on by default. SLUB boots by default with
+ the runtime debug capabilities switched off. Enabling this is
+ equivalent to specifying the "slub_debug" parameter on boot.
+ There is no support for more fine grained debug control like
+ possible with slub_debug=xxx. SLUB debugging may be switched
+ 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 && 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 HAVE_DEBUG_KMEMLEAK
+ bool
+
+config DEBUG_KMEMLEAK
+ bool "Kernel memory leak detector"
+ depends on DEBUG_KERNEL && HAVE_DEBUG_KMEMLEAK
+ select DEBUG_FS
+ 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 && m
+ help
+ This option enables a module that explicitly leaks memory.
+
+ If unsure, say N.
+
+config DEBUG_KMEMLEAK_DEFAULT_OFF
+ bool "Default kmemleak to off"
+ depends on DEBUG_KMEMLEAK
+ help
+ Say Y here to disable kmemleak by default. It can then be enabled
+ on the command line via kmemleak=on.
+
+config DEBUG_STACK_USAGE
+ bool "Stack utilization instrumentation"
+ depends on DEBUG_KERNEL && !IA64 && !PARISC && !METAG
+ help
+ Enables the display of the minimum amount of free stack which each
+ task has ever had available in the sysrq-T and sysrq-P debug output.
+
+ This option will slow down process creation somewhat.
+
+config DEBUG_VM
+ bool "Debug VM"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on extended checks in the virtual-memory system
+ that may impact performance.
+
+ If unsure, say N.
+
+config DEBUG_VM_RB
+ bool "Debug VM red-black trees"
+ depends on DEBUG_VM
+ help
+ Enable this to turn on more extended checks in the virtual-memory
+ system that may impact performance.
+
+ If unsure, say N.
+
+config DEBUG_VIRTUAL
+ bool "Debug VM translations"
+ depends on DEBUG_KERNEL && X86
+ help
+ Enable some costly sanity checks in virtual to page code. This can
+ catch mistakes with virt_to_page() and friends.
+
+ If unsure, say N.
+
+config DEBUG_NOMMU_REGIONS
+ bool "Debug the global anon/private NOMMU mapping region tree"
+ depends on DEBUG_KERNEL && !MMU
+ help
+ This option causes the global tree of anonymous and private mapping
+ regions to be regularly checked for invalid topology.
+
+config DEBUG_MEMORY_INIT
+ bool "Debug memory initialisation" if EXPERT
+ default !EXPERT
+ 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 MEMORY_NOTIFIER_ERROR_INJECT
+ tristate "Memory hotplug notifier error injection module"
+ depends on MEMORY_HOTPLUG_SPARSE && NOTIFIER_ERROR_INJECTION
+ help
+ This option provides the ability to inject artificial errors to
+ memory hotplug notifier chain callbacks. It is controlled through
+ debugfs interface under /sys/kernel/debug/notifier-error-inject/memory
+
+ If the notifier call chain should be failed with some events
+ notified, write the error code to "actions/<notifier event>/error".
+
+ Example: Inject memory hotplug offline error (-12 == -ENOMEM)
+
+ # cd /sys/kernel/debug/notifier-error-inject/memory
+ # echo -12 > actions/MEM_GOING_OFFLINE/error
+ # echo offline > /sys/devices/system/memory/memoryXXX/state
+ bash: echo: write error: Cannot allocate memory
+
+ To compile this code as a module, choose M here: the module will
+ be called memory-notifier-error-inject.
+
+ If unsure, say N.
+
+config DEBUG_PER_CPU_MAPS
+ bool "Debug access to per_cpu maps"
+ depends on DEBUG_KERNEL
+ depends on SMP
+ help
+ Say Y to verify that the per_cpu map being accessed has
+ been set up. This adds a fair amount of code to kernel memory
+ and decreases performance.
+
+ Say N if unsure.
+
+config DEBUG_HIGHMEM
+ bool "Highmem debugging"
+ depends on DEBUG_KERNEL && HIGHMEM
+ help
+ This options enables addition error checking for high memory systems.
+ Disable for production systems.
+
+config HAVE_DEBUG_STACKOVERFLOW
+ bool
+
+config DEBUG_STACKOVERFLOW
+ bool "Check for stack overflows"
+ depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW
+ ---help---
+ Say Y here if you want to check for overflows of kernel, IRQ
+ and exception stacks (if your archicture uses them). This
+ option will show detailed messages if free stack space drops
+ below a certain limit.
+
+ These kinds of bugs usually occur when call-chains in the
+ kernel get too deep, especially when interrupts are
+ involved.
+
+ Use this in cases where you see apparently random memory
+ corruption, especially if it appears in 'struct thread_info'
+
+ If in doubt, say "N".
+
+source "lib/Kconfig.kmemcheck"
+
+endmenu # "Memory Debugging"
+
config DEBUG_SHIRQ
bool "Debug shared IRQ handlers"
depends on DEBUG_KERNEL && GENERIC_HARDIRQS
@@ -171,6 +604,8 @@ config DEBUG_SHIRQ
Drivers ought to be able to handle interrupts coming in at those
points; some don't and need to be caught.
+menu "Debug Lockups and Hangs"
+
config LOCKUP_DETECTOR
bool "Detect Hard and Soft Lockups"
depends on DEBUG_KERNEL && !S390
@@ -242,25 +677,6 @@ config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE
default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC
default 1 if BOOTPARAM_SOFTLOCKUP_PANIC
-config PANIC_ON_OOPS
- bool "Panic on Oops"
- help
- Say Y here to enable the kernel to panic when it oopses. This
- has the same effect as setting oops=panic on the kernel command
- line.
-
- This feature is useful to ensure that the kernel does not do
- anything erroneous after an oops which could result in data
- corruption or other issues.
-
- Say N if unsure.
-
-config PANIC_ON_OOPS_VALUE
- int
- range 0 1
- default 0 if !PANIC_ON_OOPS
- default 1 if PANIC_ON_OOPS
-
config DETECT_HUNG_TASK
bool "Detect Hung Tasks"
depends on DEBUG_KERNEL
@@ -315,6 +731,27 @@ config BOOTPARAM_HUNG_TASK_PANIC_VALUE
default 0 if !BOOTPARAM_HUNG_TASK_PANIC
default 1 if BOOTPARAM_HUNG_TASK_PANIC
+endmenu # "Debug lockups and hangs"
+
+config PANIC_ON_OOPS
+ bool "Panic on Oops"
+ help
+ Say Y here to enable the kernel to panic when it oopses. This
+ has the same effect as setting oops=panic on the kernel command
+ line.
+
+ This feature is useful to ensure that the kernel does not do
+ anything erroneous after an oops which could result in data
+ corruption or other issues.
+
+ Say N if unsure.
+
+config PANIC_ON_OOPS_VALUE
+ int
+ range 0 1
+ default 0 if !PANIC_ON_OOPS
+ default 1 if PANIC_ON_OOPS
+
config SCHED_DEBUG
bool "Collect scheduler debugging info"
depends on DEBUG_KERNEL && PROC_FS
@@ -350,158 +787,6 @@ config TIMER_STATS
(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_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_RCU_HEAD
- bool "Debug RCU callbacks objects"
- depends on DEBUG_OBJECTS
- help
- Enable this to turn on debugging of RCU list heads (call_rcu() usage).
-
-config DEBUG_OBJECTS_PERCPU_COUNTER
- bool "Debug percpu counter objects"
- depends on DEBUG_OBJECTS
- help
- If you say Y here, additional code will be inserted into the
- percpu counter routines to track the life time of percpu counter
- objects and validate the percpu counter operations.
-
-config DEBUG_OBJECTS_ENABLE_DEFAULT
- int "debug_objects bootup default value (0-1)"
- range 0 1
- default "1"
- depends on DEBUG_OBJECTS
- help
- Debug objects boot parameter default value
-
-config DEBUG_SLAB
- bool "Debug slab memory allocations"
- 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
- memory. This can make kmalloc/kfree-intensive workloads much slower.
-
-config DEBUG_SLAB_LEAK
- bool "Memory leak debugging"
- depends on DEBUG_SLAB
-
-config SLUB_DEBUG_ON
- bool "SLUB debugging on by default"
- depends on SLUB && SLUB_DEBUG && !KMEMCHECK
- default n
- help
- Boot with debugging on by default. SLUB boots by default with
- the runtime debug capabilities switched off. Enabling this is
- equivalent to specifying the "slub_debug" parameter on boot.
- There is no support for more fine grained debug control like
- possible with slub_debug=xxx. SLUB debugging may be switched
- 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 && 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 HAVE_DEBUG_KMEMLEAK
- bool
-
-config DEBUG_KMEMLEAK
- bool "Kernel memory leak detector"
- depends on DEBUG_KERNEL && HAVE_DEBUG_KMEMLEAK
- select DEBUG_FS
- 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 && m
- help
- This option enables a module that explicitly leaks memory.
-
- If unsure, say N.
-
-config DEBUG_KMEMLEAK_DEFAULT_OFF
- bool "Default kmemleak to off"
- depends on DEBUG_KMEMLEAK
- help
- Say Y here to disable kmemleak by default. It can then be enabled
- on the command line via kmemleak=on.
-
config DEBUG_PREEMPT
bool "Debug preemptible kernel"
depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT
@@ -512,6 +797,8 @@ config DEBUG_PREEMPT
if kernel code uses it in a preemption-unsafe way. Also, the kernel
will detect preemption count underflows.
+menu "Lock Debugging (spinlocks, mutexes, etc...)"
+
config DEBUG_RT_MUTEXES
bool "RT Mutex debugging, deadlock detection"
depends on DEBUG_KERNEL && RT_MUTEXES
@@ -654,12 +941,6 @@ config DEBUG_LOCKDEP
additional runtime checks to debug itself, at the price
of more runtime overhead.
-config TRACE_IRQFLAGS
- bool
- help
- Enables hooks to interrupt enabling and disabling for
- either tracing or lock debugging.
-
config DEBUG_ATOMIC_SLEEP
bool "Sleep inside atomic section checking"
select PREEMPT_COUNT
@@ -681,18 +962,17 @@ config DEBUG_LOCKING_API_SELFTESTS
The following locking APIs are covered: spinlocks, rwlocks,
mutexes and rwsems.
-config STACKTRACE
- bool
- depends on STACKTRACE_SUPPORT
+endmenu # lock debugging
-config DEBUG_STACK_USAGE
- bool "Stack utilization instrumentation"
- depends on DEBUG_KERNEL && !IA64 && !PARISC && !METAG
+config TRACE_IRQFLAGS
+ bool
help
- Enables the display of the minimum amount of free stack which each
- task has ever had available in the sysrq-T and sysrq-P debug output.
+ Enables hooks to interrupt enabling and disabling for
+ either tracing or lock debugging.
- This option will slow down process creation somewhat.
+config STACKTRACE
+ bool
+ depends on STACKTRACE_SUPPORT
config DEBUG_KOBJECT
bool "kobject debugging"
@@ -701,13 +981,6 @@ config DEBUG_KOBJECT
If you say Y here, some extra kobject debugging messages will be sent
to the syslog.
-config DEBUG_HIGHMEM
- bool "Highmem debugging"
- depends on DEBUG_KERNEL && HIGHMEM
- help
- This options enables addition error checking for high memory systems.
- Disable for production systems.
-
config HAVE_DEBUG_BUGVERBOSE
bool
@@ -720,66 +993,6 @@ config DEBUG_BUGVERBOSE
of the BUG call as well as the EIP and oops trace. This aids
debugging but costs about 70-100K of memory.
-config DEBUG_INFO
- bool "Compile the kernel with debug info"
- depends on DEBUG_KERNEL
- help
- If you say Y here the resulting kernel image will include
- debugging info resulting in a larger kernel image.
- This adds debug symbols to the kernel and modules (gcc -g), and
- is needed if you intend to use kernel crashdump or binary object
- tools like crash, kgdb, LKCD, gdb, etc on the kernel.
- Say Y here only if you plan to debug the kernel.
-
- If unsure, say N.
-
-config DEBUG_INFO_REDUCED
- bool "Reduce debugging information"
- depends on DEBUG_INFO
- help
- If you say Y here gcc is instructed to generate less debugging
- information for structure types. This means that tools that
- need full debugging information (like kgdb or systemtap) won't
- be happy. But if you merely need debugging information to
- resolve line numbers there is no loss. Advantage is that
- build directory object sizes shrink dramatically over a full
- DEBUG_INFO build and compile times are reduced too.
- Only works with newer gcc versions.
-
-config DEBUG_VM
- bool "Debug VM"
- depends on DEBUG_KERNEL
- help
- Enable this to turn on extended checks in the virtual-memory system
- that may impact performance.
-
- If unsure, say N.
-
-config DEBUG_VM_RB
- bool "Debug VM red-black trees"
- depends on DEBUG_VM
- help
- Enable this to turn on more extended checks in the virtual-memory
- system that may impact performance.
-
- If unsure, say N.
-
-config DEBUG_VIRTUAL
- bool "Debug VM translations"
- depends on DEBUG_KERNEL && X86
- help
- Enable some costly sanity checks in virtual to page code. This can
- catch mistakes with virt_to_page() and friends.
-
- If unsure, say N.
-
-config DEBUG_NOMMU_REGIONS
- bool "Debug the global anon/private NOMMU mapping region tree"
- depends on DEBUG_KERNEL && !MMU
- help
- This option causes the global tree of anonymous and private mapping
- regions to be regularly checked for invalid topology.
-
config DEBUG_WRITECOUNT
bool "Debug filesystem writers count"
depends on DEBUG_KERNEL
@@ -790,18 +1003,6 @@ config DEBUG_WRITECOUNT
If unsure, say N.
-config DEBUG_MEMORY_INIT
- bool "Debug memory initialisation" if EXPERT
- default !EXPERT
- 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
@@ -811,15 +1012,6 @@ config DEBUG_LIST
If unsure, say N.
-config TEST_LIST_SORT
- bool "Linked list sorting test"
- depends on DEBUG_KERNEL
- help
- Enable this to turn on 'list_sort()' function test. This test is
- executed only once during system boot, so affects only boot time.
-
- If unsure, say N.
-
config DEBUG_SG
bool "Debug SG table operations"
depends on DEBUG_KERNEL
@@ -855,45 +1047,6 @@ config DEBUG_CREDENTIALS
If unsure, say N.
-#
-# Select this config option from the architecture Kconfig, if 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 || FRV || UML || \
- AVR32 || SUPERH || BLACKFIN || MN10300 || METAG) || \
- ARCH_WANT_FRAME_POINTERS
- default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS
- help
- If you say Y here the resulting kernel image will be slightly
- larger and slower, but it gives very useful debugging information
- in case of kernel bugs. (precise oopses/stacktraces/warnings)
-
-config BOOT_PRINTK_DELAY
- bool "Delay each boot printk message by N milliseconds"
- depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY
- help
- This build option allows you to read kernel boot messages
- by inserting a short delay after each one. The delay is
- specified in milliseconds on the kernel command line,
- using "boot_delay=N".
-
- It is likely that you would also need to use "lpj=M" to preset
- the "loops per jiffie" value.
- See a previous boot log for the "lpj" value to use for your
- system, and then set "lpj=M" before setting "boot_delay=N".
- NOTE: Using this option may adversely affect SMP systems.
- I.e., processors other than the first one may not boot up.
- BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect
- what it believes to be lockup conditions.
-
menu "RCU Debugging"
config PROVE_RCU
@@ -1032,33 +1185,6 @@ config RCU_TRACE
endmenu # "RCU Debugging"
-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
@@ -1086,47 +1212,6 @@ config DEBUG_BLOCK_EXT_DEVT
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 DEBUG_PER_CPU_MAPS
- bool "Debug access to per_cpu maps"
- depends on DEBUG_KERNEL
- depends on SMP
- help
- Say Y to verify that the per_cpu map being accessed has
- been set up. This adds a fair amount of code to kernel memory
- and decreases performance.
-
- Say N if unsure.
-
-config LKDTM
- tristate "Linux Kernel Dump Test Tool Module"
- depends on DEBUG_FS
- depends on BLOCK
- default n
- help
- This module enables testing of the different dumping mechanisms by
- inducing system failures at predefined crash points.
- If you don't need it: say N
- Choose M here to compile this code as a module. The module will be
- called lkdtm.
-
- Documentation on how to use the module can be found in
- Documentation/fault-injection/provoke-crashes.txt
-
config NOTIFIER_ERROR_INJECTION
tristate "Notifier error injection"
depends on DEBUG_KERNEL
@@ -1186,29 +1271,6 @@ config PM_NOTIFIER_ERROR_INJECT
If unsure, say N.
-config MEMORY_NOTIFIER_ERROR_INJECT
- tristate "Memory hotplug notifier error injection module"
- depends on MEMORY_HOTPLUG_SPARSE && NOTIFIER_ERROR_INJECTION
- help
- This option provides the ability to inject artificial errors to
- memory hotplug notifier chain callbacks. It is controlled through
- debugfs interface under /sys/kernel/debug/notifier-error-inject/memory
-
- If the notifier call chain should be failed with some events
- notified, write the error code to "actions/<notifier event>/error".
-
- Example: Inject memory hotplug offline error (-12 == -ENOMEM)
-
- # cd /sys/kernel/debug/notifier-error-inject/memory
- # echo -12 > actions/MEM_GOING_OFFLINE/error
- # echo offline > /sys/devices/system/memory/memoryXXX/state
- bash: echo: write error: Cannot allocate memory
-
- To compile this code as a module, choose M here: the module will
- be called memory-notifier-error-inject.
-
- If unsure, say N.
-
config OF_RECONFIG_NOTIFIER_ERROR_INJECT
tristate "OF reconfig notifier error injection module"
depends on OF_DYNAMIC && NOTIFIER_ERROR_INJECTION
@@ -1323,9 +1385,61 @@ config DEBUG_STRICT_USER_COPY_CHECKS
If unsure, say N.
-source mm/Kconfig.debug
source kernel/trace/Kconfig
+menu "Runtime Testing"
+
+config LKDTM
+ tristate "Linux Kernel Dump Test Tool Module"
+ depends on DEBUG_FS
+ depends on BLOCK
+ default n
+ help
+ This module enables testing of the different dumping mechanisms by
+ inducing system failures at predefined crash points.
+ If you don't need it: say N
+ Choose M here to compile this code as a module. The module will be
+ called lkdtm.
+
+ Documentation on how to use the module can be found in
+ Documentation/fault-injection/provoke-crashes.txt
+
+config TEST_LIST_SORT
+ bool "Linked list sorting test"
+ depends on DEBUG_KERNEL
+ help
+ Enable this to turn on 'list_sort()' function test. This test is
+ executed only once during system boot, so affects only boot time.
+
+ If unsure, say N.
+
+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 RBTREE_TEST
tristate "Red-Black tree test"
depends on m && DEBUG_KERNEL
@@ -1339,6 +1453,34 @@ config INTERVAL_TREE_TEST
help
A benchmark measuring the performance of the interval tree library
+config ATOMIC64_SELFTEST
+ bool "Perform an atomic64_t self-test at boot"
+ help
+ Enable this option to test the atomic64_t functions at boot.
+
+ If unsure, say N.
+
+config ASYNC_RAID6_TEST
+ tristate "Self test for hardware accelerated raid6 recovery"
+ depends on ASYNC_RAID6_RECOV
+ select ASYNC_MEMCPY
+ ---help---
+ This is a one-shot self test that permutes through the
+ recovery of all the possible two disk failure scenarios for a
+ N-disk array. Recovery is performed with the asynchronous
+ raid6 recovery routines, and will optionally use an offload
+ engine if one is available.
+
+ If unsure, say N.
+
+config TEST_STRING_HELPERS
+ tristate "Test functions located in the string_helpers module at runtime"
+
+config TEST_KSTRTOX
+ tristate "Test kstrto*() family of functions at runtime"
+
+endmenu # runtime tests
+
config PROVIDE_OHCI1394_DMA_INIT
bool "Remote debugging over FireWire early on boot"
depends on PCI && X86
@@ -1388,75 +1530,6 @@ config BUILD_DOCSRC
Say N if you are unsure.
-config DYNAMIC_DEBUG
- bool "Enable dynamic printk() support"
- default n
- depends on PRINTK
- 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 based on various levels of scope - per source file,
- function, module, format string, and line number. This mechanism
- implicitly compiles in all pr_debug() and dev_dbg() calls, which
- enlarges the kernel text size by about 2%.
-
- If a source file is compiled with DEBUG flag set, any
- pr_debug() calls in it are enabled by default, but can be
- disabled at runtime as below. Note that DEBUG flag is
- turned on by many CONFIG_*DEBUG* options.
-
- Usage:
-
- Dynamic debugging is controlled via the 'dynamic_debug/control' 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/control. This
- file contains a list of the debug statements that can be enabled. The
- format for each line of the file is:
-
- filename:lineno [module]function flags format
-
- 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:
-
- nullarbor:~ # cat <debugfs>/dynamic_debug/control
- # 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"
-
- Example usage:
-
- // enable the message at line 1603 of file svcsock.c
- nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
- <debugfs>/dynamic_debug/control
-
- // enable all the messages in file svcsock.c
- nullarbor:~ # echo -n 'file svcsock.c +p' >
- <debugfs>/dynamic_debug/control
-
- // enable all the messages in the NFS server module
- nullarbor:~ # echo -n 'module nfsd +p' >
- <debugfs>/dynamic_debug/control
-
- // enable all 12 messages in the function svc_process()
- nullarbor:~ # echo -n 'func svc_process +p' >
- <debugfs>/dynamic_debug/control
-
- // disable all 12 messages in the function svc_process()
- nullarbor:~ # echo -n 'func svc_process -p' >
- <debugfs>/dynamic_debug/control
-
- See Documentation/dynamic-debug-howto.txt for additional information.
-
config DMA_API_DEBUG
bool "Enable debugging of DMA-API usage"
depends on HAVE_DMA_API_DEBUG
@@ -1468,34 +1541,7 @@ config DMA_API_DEBUG
This option causes a performance degredation. Use only if you want
to debug device drivers. If unsure, say N.
-config ATOMIC64_SELFTEST
- bool "Perform an atomic64_t self-test at boot"
- help
- Enable this option to test the atomic64_t functions at boot.
-
- If unsure, say N.
-
-config ASYNC_RAID6_TEST
- tristate "Self test for hardware accelerated raid6 recovery"
- depends on ASYNC_RAID6_RECOV
- select ASYNC_MEMCPY
- ---help---
- This is a one-shot self test that permutes through the
- recovery of all the possible two disk failure scenarios for a
- N-disk array. Recovery is performed with the asynchronous
- raid6 recovery routines, and will optionally use an offload
- engine if one is available.
-
- If unsure, say N.
-
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
-source "lib/Kconfig.kmemcheck"
-
-config TEST_STRING_HELPERS
- tristate "Test functions located in the string_helpers module at runtime"
-
-config TEST_KSTRTOX
- tristate "Test kstrto*() family of functions at runtime"