From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kurz Subject: Re: [V9fs-developer] [PATCH] 9p/trans_virtio: discard zero-length reply Date: Thu, 8 Feb 2018 18:52:32 +0100 Message-ID: <20180208185232.46fca063@bahia.lan> References: <151665492548.14372.18325892476788349632.stgit@bahia.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Latchesar Ionkov , Eric Van Hensbergen , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Ron Minnich , "David S. Miller" To: v9fs-developer@lists.sourceforge.net, "Michael S. Tsirkin" Return-path: In-Reply-To: <151665492548.14372.18325892476788349632.stgit@bahia.lan> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Ping ? Michael, Since this is virtio code and you have acked the QEMU part of the fix already, would you be kind enough to take this through your tree ? Cheers, -- Greg On Mon, 22 Jan 2018 22:02:05 +0100 Greg Kurz wrote: > 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 > --- > net/9p/trans_virtio.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c > index 0845aad4ba51..ca08c72ef4de 100644 > --- a/net/9p/trans_virtio.c > +++ b/net/9p/trans_virtio.c > @@ -171,7 +171,8 @@ static void req_done(struct virtqueue *vq) > spin_unlock_irqrestore(&chan->lock, flags); > /* Wakeup if anyone waiting for VirtIO ring space. */ > wake_up(chan->vc_wq); > - p9_client_cb(chan->client, req, REQ_STATUS_RCVD); > + if (len) > + p9_client_cb(chan->client, req, REQ_STATUS_RCVD); > } > } > > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > V9fs-developer mailing list > V9fs-developer@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/v9fs-developer