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-rw-r--r--lib/Kconfig.debug6
-rw-r--r--lib/Kconfig.kmemcheck91
2 files changed, 95 insertions, 2 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 116a35051be..6b0c2d8a212 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -300,7 +300,7 @@ config DEBUG_OBJECTS_ENABLE_DEFAULT
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
@@ -312,7 +312,7 @@ config DEBUG_SLAB_LEAK
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
@@ -996,3 +996,5 @@ config DMA_API_DEBUG
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
+
+source "lib/Kconfig.kmemcheck"
diff --git a/lib/Kconfig.kmemcheck b/lib/Kconfig.kmemcheck
new file mode 100644
index 00000000000..603c81b6654
--- /dev/null
+++ b/lib/Kconfig.kmemcheck
@@ -0,0 +1,91 @@
+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.
+