| Pekka Enberg | 0a4af3b | 2009-02-26 21:38:56 +0200 | [diff] [blame] | 1 | config HAVE_ARCH_KMEMCHECK |
| 2 | bool |
| 3 | |
| 4 | menuconfig KMEMCHECK |
| 5 | bool "kmemcheck: trap use of uninitialized memory" |
| 6 | depends on DEBUG_KERNEL |
| 7 | depends on !X86_USE_3DNOW |
| 8 | depends on SLUB || SLAB |
| 9 | depends on !CC_OPTIMIZE_FOR_SIZE |
| 10 | depends on !FUNCTION_TRACER |
| 11 | select FRAME_POINTER |
| 12 | select STACKTRACE |
| 13 | default n |
| 14 | help |
| 15 | This option enables tracing of dynamically allocated kernel memory |
| 16 | to see if memory is used before it has been given an initial value. |
| 17 | Be aware that this requires half of your memory for bookkeeping and |
| 18 | will insert extra code at *every* read and write to tracked memory |
| 19 | thus slow down the kernel code (but user code is unaffected). |
| 20 | |
| 21 | The kernel may be started with kmemcheck=0 or kmemcheck=1 to disable |
| 22 | or enable kmemcheck at boot-time. If the kernel is started with |
| 23 | kmemcheck=0, the large memory and CPU overhead is not incurred. |
| 24 | |
| 25 | choice |
| 26 | prompt "kmemcheck: default mode at boot" |
| 27 | depends on KMEMCHECK |
| 28 | default KMEMCHECK_ONESHOT_BY_DEFAULT |
| 29 | help |
| 30 | This option controls the default behaviour of kmemcheck when the |
| 31 | kernel boots and no kmemcheck= parameter is given. |
| 32 | |
| 33 | config KMEMCHECK_DISABLED_BY_DEFAULT |
| 34 | bool "disabled" |
| 35 | depends on KMEMCHECK |
| 36 | |
| 37 | config KMEMCHECK_ENABLED_BY_DEFAULT |
| 38 | bool "enabled" |
| 39 | depends on KMEMCHECK |
| 40 | |
| 41 | config KMEMCHECK_ONESHOT_BY_DEFAULT |
| 42 | bool "one-shot" |
| 43 | depends on KMEMCHECK |
| 44 | help |
| 45 | In one-shot mode, only the first error detected is reported before |
| 46 | kmemcheck is disabled. |
| 47 | |
| 48 | endchoice |
| 49 | |
| 50 | config KMEMCHECK_QUEUE_SIZE |
| 51 | int "kmemcheck: error queue size" |
| 52 | depends on KMEMCHECK |
| 53 | default 64 |
| 54 | help |
| 55 | Select the maximum number of errors to store in the queue. Since |
| 56 | errors can occur virtually anywhere and in any context, we need a |
| 57 | temporary storage area which is guarantueed not to generate any |
| 58 | other faults. The queue will be emptied as soon as a tasklet may |
| 59 | be scheduled. If the queue is full, new error reports will be |
| 60 | lost. |
| 61 | |
| 62 | config KMEMCHECK_SHADOW_COPY_SHIFT |
| 63 | int "kmemcheck: shadow copy size (5 => 32 bytes, 6 => 64 bytes)" |
| 64 | depends on KMEMCHECK |
| 65 | range 2 8 |
| 66 | default 5 |
| 67 | help |
| 68 | Select the number of shadow bytes to save along with each entry of |
| 69 | the queue. These bytes indicate what parts of an allocation are |
| 70 | initialized, uninitialized, etc. and will be displayed when an |
| 71 | error is detected to help the debugging of a particular problem. |
| 72 | |
| 73 | config KMEMCHECK_PARTIAL_OK |
| 74 | bool "kmemcheck: allow partially uninitialized memory" |
| 75 | depends on KMEMCHECK |
| 76 | default y |
| 77 | help |
| 78 | This option works around certain GCC optimizations that produce |
| 79 | 32-bit reads from 16-bit variables where the upper 16 bits are |
| 80 | thrown away afterwards. This may of course also hide some real |
| 81 | bugs. |
| 82 | |
| 83 | config KMEMCHECK_BITOPS_OK |
| 84 | bool "kmemcheck: allow bit-field manipulation" |
| 85 | depends on KMEMCHECK |
| 86 | default n |
| 87 | help |
| 88 | This option silences warnings that would be generated for bit-field |
| 89 | accesses where not all the bits are initialized at the same time. |
| 90 | This may also hide some real bugs. |
| 91 | |