diff --git a/include/linux/kcsan-checks.h b/include/linux/kcsan-checks.h
index 4ef5233..8f9f6e2 100644
--- a/include/linux/kcsan-checks.h
+++ b/include/linux/kcsan-checks.h
@@ -152,9 +152,9 @@ static inline void kcsan_check_access(const volatile void *ptr, size_t size,
 #endif
 
 /**
- * ASSERT_EXCLUSIVE_WRITER - assert no other threads are writing @var
+ * ASSERT_EXCLUSIVE_WRITER - assert no concurrent writes to @var
  *
- * Assert that there are no other threads writing @var; other readers are
+ * Assert that there are no concurrent writes to @var; other readers are
  * allowed. This assertion can be used to specify properties of concurrent code,
  * where violation cannot be detected as a normal data race.
  *
@@ -171,11 +171,11 @@ static inline void kcsan_check_access(const volatile void *ptr, size_t size,
 	__kcsan_check_access(&(var), sizeof(var), KCSAN_ACCESS_ASSERT)
 
 /**
- * ASSERT_EXCLUSIVE_ACCESS - assert no other threads are accessing @var
+ * ASSERT_EXCLUSIVE_ACCESS - assert no concurrent accesses to @var
  *
- * Assert that no other thread is accessing @var (no readers nor writers). This
- * assertion can be used to specify properties of concurrent code, where
- * violation cannot be detected as a normal data race.
+ * Assert that there are no concurrent accesses to @var (no readers nor
+ * writers). This assertion can be used to specify properties of concurrent
+ * code, where violation cannot be detected as a normal data race.
  *
  * For example, in a reference-counting algorithm where exclusive access is
  * expected after the refcount reaches 0. We can check that this property
@@ -191,4 +191,61 @@ static inline void kcsan_check_access(const volatile void *ptr, size_t size,
 #define ASSERT_EXCLUSIVE_ACCESS(var)                                           \
 	__kcsan_check_access(&(var), sizeof(var), KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT)
 
+/**
+ * ASSERT_EXCLUSIVE_BITS - assert no concurrent writes to subset of bits in @var
+ *
+ * Bit-granular variant of ASSERT_EXCLUSIVE_WRITER(var).
+ *
+ * Assert that there are no concurrent writes to a subset of bits in @var;
+ * concurrent readers are permitted. This assertion captures more detailed
+ * bit-level properties, compared to the other (word granularity) assertions.
+ * Only the bits set in @mask are checked for concurrent modifications, while
+ * ignoring the remaining bits, i.e. concurrent writes (or reads) to ~@mask bits
+ * are ignored.
+ *
+ * Use this for variables, where some bits must not be modified concurrently,
+ * yet other bits are expected to be modified concurrently.
+ *
+ * For example, variables where, after initialization, some bits are read-only,
+ * but other bits may still be modified concurrently. A reader may wish to
+ * assert that this is true as follows:
+ *
+ *	ASSERT_EXCLUSIVE_BITS(flags, READ_ONLY_MASK);
+ *	foo = (READ_ONCE(flags) & READ_ONLY_MASK) >> READ_ONLY_SHIFT;
+ *
+ *   Note: The access that immediately follows ASSERT_EXCLUSIVE_BITS() is
+ *   assumed to access the masked bits only, and KCSAN optimistically assumes it
+ *   is therefore safe, even in the presence of data races, and marking it with
+ *   READ_ONCE() is optional from KCSAN's point-of-view. We caution, however,
+ *   that it may still be advisable to do so, since we cannot reason about all
+ *   compiler optimizations when it comes to bit manipulations (on the reader
+ *   and writer side). If you are sure nothing can go wrong, we can write the
+ *   above simply as:
+ *
+ *	ASSERT_EXCLUSIVE_BITS(flags, READ_ONLY_MASK);
+ *	foo = (flags & READ_ONLY_MASK) >> READ_ONLY_SHIFT;
+ *
+ * Another example, where this may be used, is when certain bits of @var may
+ * only be modified when holding the appropriate lock, but other bits may still
+ * be modified concurrently. Writers, where other bits may change concurrently,
+ * could use the assertion as follows:
+ *
+ *	spin_lock(&foo_lock);
+ *	ASSERT_EXCLUSIVE_BITS(flags, FOO_MASK);
+ *	old_flags = READ_ONCE(flags);
+ *	new_flags = (old_flags & ~FOO_MASK) | (new_foo << FOO_SHIFT);
+ *	if (cmpxchg(&flags, old_flags, new_flags) != old_flags) { ... }
+ *	spin_unlock(&foo_lock);
+ *
+ * @var variable to assert on
+ * @mask only check for modifications to bits set in @mask
+ */
+#define ASSERT_EXCLUSIVE_BITS(var, mask)                                       \
+	do {                                                                   \
+		kcsan_set_access_mask(mask);                                   \
+		__kcsan_check_access(&(var), sizeof(var), KCSAN_ACCESS_ASSERT);\
+		kcsan_set_access_mask(0);                                      \
+		kcsan_atomic_next(1);                                          \
+	} while (0)
+
 #endif /* _LINUX_KCSAN_CHECKS_H */