Re: [PATCH] doc: clarification about setting SO_ZEROCOPY

---
 Documentation/networking/msg_zerocopy.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/networking/msg_zerocopy.rst b/Documentation/networking/msg_zerocopy.rst
index 77f6d7e..c3380f4 100644
--- a/Documentation/networking/msg_zerocopy.rst
+++ b/Documentation/networking/msg_zerocopy.rst

@@ -72,6 +72,10 @@ this flag, a process must first signal intent by setting a socket option:
        if (setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, &one, sizeof(one)))
                error(1, errno, "setsockopt zerocopy");

+Setting the socket option only works when the socket is in its initial
+(TCP_CLOSED) state.  Trying to set the option for a socket returned by accept(),
+for example, will lead to an EBUSY error. In this case, the option should be set
+to the listening socket and it will be inherited by the accepted sockets.