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+config HAVE_ARCH_KASAN
+ bool
+
+if HAVE_ARCH_KASAN
+
+config KASAN
+ bool "KASan: runtime memory debugger"
+ depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
+ select SLUB_DEBUG if SLUB
+ select CONSTRUCTORS
+ select STACKDEPOT
+ help
+ Enables kernel address sanitizer - runtime memory debugger,
+ designed to find out-of-bounds accesses and use-after-free bugs.
+ This is strictly a debugging feature and it requires a gcc version
+ of 4.9.2 or later. Detection of out of bounds accesses to stack or
+ global variables requires gcc 5.0 or later.
+ This feature consumes about 1/8 of available memory and brings about
+ ~x3 performance slowdown.
+ For better error detection enable CONFIG_STACKTRACE.
+ Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
+ (the resulting kernel does not boot).
+
+config KASAN_EXTRA
+ bool "KAsan: extra checks"
+ depends on KASAN && DEBUG_KERNEL && !COMPILE_TEST
+ help
+ This enables further checks in the kernel address sanitizer, for now
+ it only includes the address-use-after-scope check that can lead
+ to excessive kernel stack usage, frame size warnings and longer
+ compile time.
+ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more
+
+
+choice
+ prompt "Instrumentation type"
+ depends on KASAN
+ default KASAN_OUTLINE
+
+config KASAN_OUTLINE
+ bool "Outline instrumentation"
+ help
+ Before every memory access compiler insert function call
+ __asan_load*/__asan_store*. These functions performs check
+ of shadow memory. This is slower than inline instrumentation,
+ however it doesn't bloat size of kernel's .text section so
+ much as inline does.
+
+config KASAN_INLINE
+ bool "Inline instrumentation"
+ help
+ Compiler directly inserts code checking shadow memory before
+ memory accesses. This is faster than outline (in some workloads
+ it gives about x2 boost over outline instrumentation), but
+ make kernel's .text size much bigger.
+ This requires a gcc version of 5.0 or later.
+
+endchoice
+
+config TEST_KASAN
+ tristate "Module for testing kasan for bug detection"
+ depends on m && KASAN
+ help
+ This is a test module doing various nasty things like
+ out of bounds accesses, use after free. It is useful for testing
+ kernel debugging features like kernel address sanitizer.
+
+endif