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+# SPDX-License-Identifier: GPL-2.0-only
+config HAVE_ARCH_KMSAN
+ bool
+
+config HAVE_KMSAN_COMPILER
+ # Clang versions <14.0.0 also support -fsanitize=kernel-memory, but not
+ # all the features necessary to build the kernel with KMSAN.
+ depends on CC_IS_CLANG && CLANG_VERSION >= 140000
+ def_bool $(cc-option,-fsanitize=kernel-memory -mllvm -msan-disable-checks=1)
+
+config KMSAN
+ bool "KMSAN: detector of uninitialized values use"
+ depends on HAVE_ARCH_KMSAN && HAVE_KMSAN_COMPILER
+ depends on SLUB && DEBUG_KERNEL && !KASAN && !KCSAN
+ depends on !PREEMPT_RT
+ select STACKDEPOT
+ select STACKDEPOT_ALWAYS_INIT
+ help
+ KernelMemorySanitizer (KMSAN) is a dynamic detector of uses of
+ uninitialized values in the kernel. It is based on compiler
+ instrumentation provided by Clang and thus requires Clang to build.
+
+ An important note is that KMSAN is not intended for production use,
+ because it drastically increases kernel memory footprint and slows
+ the whole system down.
+
+ See <file:Documentation/dev-tools/kmsan.rst> for more details.
+
+if KMSAN
+
+config HAVE_KMSAN_PARAM_RETVAL
+ # -fsanitize-memory-param-retval is supported only by Clang >= 14.
+ depends on HAVE_KMSAN_COMPILER
+ def_bool $(cc-option,-fsanitize=kernel-memory -fsanitize-memory-param-retval)
+
+config KMSAN_CHECK_PARAM_RETVAL
+ bool "Check for uninitialized values passed to and returned from functions"
+ default y
+ depends on HAVE_KMSAN_PARAM_RETVAL
+ help
+ If the compiler supports -fsanitize-memory-param-retval, KMSAN will
+ eagerly check every function parameter passed by value and every
+ function return value.
+
+ Disabling KMSAN_CHECK_PARAM_RETVAL will result in tracking shadow for
+ function parameters and return values across function borders. This
+ is a more relaxed mode, but it generates more instrumentation code and
+ may potentially report errors in corner cases when non-instrumented
+ functions call instrumented ones.
+
+config KMSAN_KUNIT_TEST
+ tristate "KMSAN integration test suite" if !KUNIT_ALL_TESTS
+ default KUNIT_ALL_TESTS
+ depends on TRACEPOINTS && KUNIT
+ help
+ Test suite for KMSAN, testing various error detection scenarios,
+ and checking that reports are correctly output to console.
+
+ Say Y here if you want the test to be built into the kernel and run
+ during boot; say M if you want the test to build as a module; say N
+ if you are unsure.
+
+endif