From: Sjur Brændeland <sjur.brandeland@xxxxxxxxxxxxxx>
This reverts commit 8078db789a92b10ff6e2d713231b5367e014c53b, and
adds a lengthy comment explaining the problem area.
The reverted patch caused opening of ports to fail for rproc_serial.
In probe guest_connected was set to true, but port_fops_open()
fails with -EMFILE if guest_connected already is true.
Signed-off-by: Sjur Brændeland <sjur.brandeland@xxxxxxxxxxxxxx>
---
drivers/char/virtio_console.c | 22 ++++++++++++++++------
1 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e905d5f..e6ba6b7 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1436,7 +1436,7 @@ static int add_port(struct ports_device *portdev, u32 id)
* rproc_serial does not want the console port, only
* the generic port implementation.
*/
- port->host_connected = port->guest_connected = true;
+ port->host_connected = true;
else if (!use_multiport(port->portdev)) {
/*
* If we're not using multiport support,
@@ -1752,13 +1752,23 @@ static void in_intr(struct virtqueue *vq)
port->inbuf = get_inbuf(port);
/*
- * Don't queue up data when port is closed. This condition
+ * Normally the port should not accept data when the port is
+ * closed. For generic serial ports, the host won't (shouldn't)
+ * send data till the guest is connected. But this condition
* can be reached when a console port is not yet connected (no
- * tty is spawned) and the host sends out data to console
- * ports. For generic serial ports, the host won't
- * (shouldn't) send data till the guest is connected.
+ * tty is spawned) and the other side sends out data over the
+ * vring, or when a remote devices start sending data before
+ * the ports are opened.
+ *
+ * A generic serial port will discard data if not connected,
+ * while console ports and rproc-serial ports accepts data at
+ * any time. rproc-serial is initiated with guest_connected to
+ * false because port_fops_open expects this. Console ports are
+ * hooked up with an HVC console and is initialized with
+ * guest_connected to true.
*/
- if (!port->guest_connected)
+
+ if (!port->guest_connected && !is_rproc_serial(port->portdev->vdev))
discard_port_data(port);
spin_unlock_irqrestore(&port->inbuf_lock, flags);
--
1.7.5.4
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