Re: [PATCH V3 net-next] can-raw: add msg_flags to distinguish local traffic

diff --git a/Documentation/networking/can.txt

b/Documentation/networking/can.txt index cd79735..bc015d0 100644

--- a/Documentation/networking/can.txt
+++ b/Documentation/networking/can.txt

@@ -22,6 +22,7 @@ This file contains
       4.1.2 RAW socket option CAN_RAW_ERR_FILTER
       4.1.3 RAW socket option CAN_RAW_LOOPBACK
       4.1.4 RAW socket option CAN_RAW_RECV_OWN_MSGS
+      4.1.5 RAW socket returned flags
     4.2 Broadcast Manager protocol sockets (SOCK_DGRAM)
     4.3 connected transport protocols (SOCK_SEQPACKET)
     4.4 unconnected transport protocols (SOCK_DGRAM)

@@ -471,6 +472,18 @@ solution for a couple of reasons:
     setsockopt(s, SOL_CAN_RAW, CAN_RAW_RECV_OWN_MSGS,
                &recv_own_msgs, sizeof(recv_own_msgs));

+  4.1.5 RAW socket returned flags
+
+  When using recvmsg() call, the msg->msg_flags may contain following

flags: +
+    MSG_DONTROUTE: set when the received frame was created on the local
host. +
+    MSG_CONFIRM: set when the frame was sent via the socket it is received
on. +        This flag can be interpreted as a 'transmission confirmation'
+	when the CAN driver supports the echo of CAN frames on driver level,
+	see 3.2 and 6.2.
+	In order to receive such messages, CAN_RAW_RECV_OWN_MSGS must be set.
+