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-rw-r--r--Documentation/memory-barriers.txt7
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diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 06e14efd86..d414e145f9 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -396,6 +396,10 @@ Memory barriers come in four basic varieties:
(2) Address-dependency barriers (historical).
+ [!] This section is marked as HISTORICAL: For more up-to-date
+ information, including how compiler transformations related to pointer
+ comparisons can sometimes cause problems, see
+ Documentation/RCU/rcu_dereference.rst.
An address-dependency barrier is a weaker form of read barrier. In the
case where two loads are performed such that the second depends on the
@@ -556,6 +560,9 @@ There are certain things that the Linux kernel memory barriers do not guarantee:
ADDRESS-DEPENDENCY BARRIERS (HISTORICAL)
----------------------------------------
+[!] This section is marked as HISTORICAL: For more up-to-date information,
+including how compiler transformations related to pointer comparisons can
+sometimes cause problems, see Documentation/RCU/rcu_dereference.rst.
As of v4.15 of the Linux kernel, an smp_mb() was added to READ_ONCE() for
DEC Alpha, which means that about the only people who need to pay attention