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Subject[PATCH] docs: kref: Clarify the use of two kref_put() in example code
Eventhough the current documentation explains that the reference count
gets incremented by both kref_init() and kref_get(), it is often
misunderstood that only one instance of kref_put() is needed in the
example code. So let's clarify that a bit.

Signed-off-by: Manivannan Sadhasivam <>
Documentation/kref.txt | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/Documentation/kref.txt b/Documentation/kref.txt
index 3af384156d7e..c61eea6f1bf2 100644
--- a/Documentation/kref.txt
+++ b/Documentation/kref.txt
@@ -128,6 +128,10 @@ since we already have a valid pointer that we own a refcount for. The
put needs no lock because nothing tries to get the data without
already holding a pointer.

+In the above example, kref_put() will be called 2 times in both success
+and error paths. This is necessary because the reference count got
+incremented 2 times by kref_init() and kref_get().
Note that the "before" in rule 1 is very important. You should never
do something like::

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