path: root/include/linux/compiler.h
diff options
Diffstat (limited to 'include/linux/compiler.h')
1 files changed, 3 insertions, 2 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 48f5aab117ae..a27f4f17c382 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -263,8 +263,9 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
* In contrast to ACCESS_ONCE these two macros will also work on aggregate
* data types like structs or unions. If the size of the accessed data
* type exceeds the word size of the machine (e.g., 32 bits or 64 bits)
- * READ_ONCE() and WRITE_ONCE() will fall back to memcpy and print a
- * compile-time warning.
+ * READ_ONCE() and WRITE_ONCE() will fall back to memcpy(). There's at
+ * least two memcpy()s: one for the __builtin_memcpy() and then one for
+ * the macro doing the copy of variable - '__u' allocated on the stack.
* Their two major use cases are: (1) Mediating communication between
* process-level code and irq/NMI handlers, all running on the same CPU,