[PATCH 3.12 31/86] xen, fbfront: fix connecting to backend

From: Jiri Slaby
Date: Thu May 04 2017 - 05:06:52 EST


From: Juergen Gross <jgross@xxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 9121b15b5628b38b4695282dc18c553440e0f79b upstream.

Connecting to the backend isn't working reliably in xen-fbfront: in
case XenbusStateInitWait of the backend has been missed the backend
transition to XenbusStateConnected will trigger the connected state
only without doing the actions required when the backend has
connected.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/video/xen-fbfront.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/xen-fbfront.c b/drivers/video/xen-fbfront.c
index 4b2d3ab870f3..fc56d1ed11fc 100644
--- a/drivers/video/xen-fbfront.c
+++ b/drivers/video/xen-fbfront.c
@@ -644,7 +644,6 @@ static void xenfb_backend_changed(struct xenbus_device *dev,
break;

case XenbusStateInitWait:
-InitWait:
xenbus_switch_state(dev, XenbusStateConnected);
break;

@@ -655,7 +654,8 @@ InitWait:
* get Connected twice here.
*/
if (dev->state != XenbusStateConnected)
- goto InitWait; /* no InitWait seen yet, fudge it */
+ /* no InitWait seen yet, fudge it */
+ xenbus_switch_state(dev, XenbusStateConnected);

if (xenbus_scanf(XBT_NIL, info->xbdev->otherend,
"request-update", "%d", &val) < 0)
--
2.12.2