3.16.57-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kurz <groug@xxxxxxxx> commit 26d99834f89e76514076d9cd06f61e56e6a509b8 upstream. When a 9p request is successfully flushed, the server is expected to just mark it as used without sending a 9p reply (ie, without writing data into the buffer). In this case, virtqueue_get_buf() will return len == 0 and we must not report a REQ_STATUS_RCVD status to the client, otherwise the client will erroneously assume the request has not been flushed. Signed-off-by: Greg Kurz <groug@xxxxxxxx> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- net/9p/trans_virtio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -164,7 +164,8 @@ static void req_done(struct virtqueue *v p9_debug(P9_DEBUG_TRANS, ": rc %p\n", rc); p9_debug(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag); req = p9_tag_lookup(chan->client, rc->tag); - p9_client_cb(chan->client, req, REQ_STATUS_RCVD); + if (len) + p9_client_cb(chan->client, req, REQ_STATUS_RCVD); } }
