|  | config HAVE_ARCH_KMEMCHECK | 
|  | bool | 
|  |  | 
|  | menuconfig KMEMCHECK | 
|  | bool "kmemcheck: trap use of uninitialized memory" | 
|  | depends on DEBUG_KERNEL | 
|  | depends on !X86_USE_3DNOW | 
|  | depends on SLUB || SLAB | 
|  | depends on !CC_OPTIMIZE_FOR_SIZE | 
|  | depends on !FUNCTION_TRACER | 
|  | select FRAME_POINTER | 
|  | select STACKTRACE | 
|  | default n | 
|  | help | 
|  | This option enables tracing of dynamically allocated kernel memory | 
|  | to see if memory is used before it has been given an initial value. | 
|  | Be aware that this requires half of your memory for bookkeeping and | 
|  | will insert extra code at *every* read and write to tracked memory | 
|  | thus slow down the kernel code (but user code is unaffected). | 
|  |  | 
|  | The kernel may be started with kmemcheck=0 or kmemcheck=1 to disable | 
|  | or enable kmemcheck at boot-time. If the kernel is started with | 
|  | kmemcheck=0, the large memory and CPU overhead is not incurred. | 
|  |  | 
|  | choice | 
|  | prompt "kmemcheck: default mode at boot" | 
|  | depends on KMEMCHECK | 
|  | default KMEMCHECK_ONESHOT_BY_DEFAULT | 
|  | help | 
|  | This option controls the default behaviour of kmemcheck when the | 
|  | kernel boots and no kmemcheck= parameter is given. | 
|  |  | 
|  | config KMEMCHECK_DISABLED_BY_DEFAULT | 
|  | bool "disabled" | 
|  | depends on KMEMCHECK | 
|  |  | 
|  | config KMEMCHECK_ENABLED_BY_DEFAULT | 
|  | bool "enabled" | 
|  | depends on KMEMCHECK | 
|  |  | 
|  | config KMEMCHECK_ONESHOT_BY_DEFAULT | 
|  | bool "one-shot" | 
|  | depends on KMEMCHECK | 
|  | help | 
|  | In one-shot mode, only the first error detected is reported before | 
|  | kmemcheck is disabled. | 
|  |  | 
|  | endchoice | 
|  |  | 
|  | config KMEMCHECK_QUEUE_SIZE | 
|  | int "kmemcheck: error queue size" | 
|  | depends on KMEMCHECK | 
|  | default 64 | 
|  | help | 
|  | Select the maximum number of errors to store in the queue. Since | 
|  | errors can occur virtually anywhere and in any context, we need a | 
|  | temporary storage area which is guarantueed not to generate any | 
|  | other faults. The queue will be emptied as soon as a tasklet may | 
|  | be scheduled. If the queue is full, new error reports will be | 
|  | lost. | 
|  |  | 
|  | config KMEMCHECK_SHADOW_COPY_SHIFT | 
|  | int "kmemcheck: shadow copy size (5 => 32 bytes, 6 => 64 bytes)" | 
|  | depends on KMEMCHECK | 
|  | range 2 8 | 
|  | default 5 | 
|  | help | 
|  | Select the number of shadow bytes to save along with each entry of | 
|  | the queue. These bytes indicate what parts of an allocation are | 
|  | initialized, uninitialized, etc. and will be displayed when an | 
|  | error is detected to help the debugging of a particular problem. | 
|  |  | 
|  | config KMEMCHECK_PARTIAL_OK | 
|  | bool "kmemcheck: allow partially uninitialized memory" | 
|  | depends on KMEMCHECK | 
|  | default y | 
|  | help | 
|  | This option works around certain GCC optimizations that produce | 
|  | 32-bit reads from 16-bit variables where the upper 16 bits are | 
|  | thrown away afterwards. This may of course also hide some real | 
|  | bugs. | 
|  |  | 
|  | config KMEMCHECK_BITOPS_OK | 
|  | bool "kmemcheck: allow bit-field manipulation" | 
|  | depends on KMEMCHECK | 
|  | default n | 
|  | help | 
|  | This option silences warnings that would be generated for bit-field | 
|  | accesses where not all the bits are initialized at the same time. | 
|  | This may also hide some real bugs. | 
|  |  |