2017-03-23 12:53:04

by Jürgen Groß

[permalink] [raw]
Subject: [PATCH] xen, fbfront: fix connecting to backend

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.

Cc: [email protected]
Signed-off-by: Juergen Gross <[email protected]>
---
drivers/video/fbdev/xen-fbfront.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c
index d0115a7..3ee309c 100644
--- a/drivers/video/fbdev/xen-fbfront.c
+++ b/drivers/video/fbdev/xen-fbfront.c
@@ -643,7 +643,6 @@ static void xenfb_backend_changed(struct xenbus_device *dev,
break;

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

@@ -654,7 +653,8 @@ static void xenfb_backend_changed(struct xenbus_device *dev,
* 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_read_unsigned(info->xbdev->otherend,
"request-update", 0))
--
2.10.2


2017-03-23 13:57:54

by Jan Beulich

[permalink] [raw]
Subject: Re: [Xen-devel] [PATCH] xen, fbfront: fix connecting to backend

>>> On 23.03.17 at 13:52, <[email protected]> wrote:
> 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.

Looks like xen-kbdfront does exactly the same - shouldn't it also be
changed then?

Jan

2017-03-23 14:11:56

by Boris Ostrovsky

[permalink] [raw]
Subject: Re: [PATCH] xen, fbfront: fix connecting to backend

On 03/23/2017 08:52 AM, Juergen Gross wrote:
> 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.
>
> Cc: [email protected]
> Signed-off-by: Juergen Gross <[email protected]>

Reviewed-by: Boris Ostrovsky <[email protected]>


2017-04-05 08:18:31

by Jürgen Groß

[permalink] [raw]
Subject: Re: [PATCH] xen, fbfront: fix connecting to backend

On 23/03/17 13:52, Juergen Gross wrote:
> 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.
>
> Cc: [email protected]
> Signed-off-by: Juergen Gross <[email protected]>

Bartlomiej, any comments? Can you please take this patch or should I
carry it through the Xen tree?


Juergen

> ---
> drivers/video/fbdev/xen-fbfront.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/video/fbdev/xen-fbfront.c b/drivers/video/fbdev/xen-fbfront.c
> index d0115a7..3ee309c 100644
> --- a/drivers/video/fbdev/xen-fbfront.c
> +++ b/drivers/video/fbdev/xen-fbfront.c
> @@ -643,7 +643,6 @@ static void xenfb_backend_changed(struct xenbus_device *dev,
> break;
>
> case XenbusStateInitWait:
> -InitWait:
> xenbus_switch_state(dev, XenbusStateConnected);
> break;
>
> @@ -654,7 +653,8 @@ static void xenfb_backend_changed(struct xenbus_device *dev,
> * 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_read_unsigned(info->xbdev->otherend,
> "request-update", 0))
>

Subject: Re: [PATCH] xen, fbfront: fix connecting to backend


Hi,

On Wednesday, April 05, 2017 10:18:21 AM Juergen Gross wrote:
> On 23/03/17 13:52, Juergen Gross wrote:
> > 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.
> >
> > Cc: [email protected]
> > Signed-off-by: Juergen Gross <[email protected]>
>
> Bartlomiej, any comments? Can you please take this patch or should I
> carry it through the Xen tree?

Looks fine to me, I will queue it for 4.11 on Friday.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Subject: Re: [PATCH] xen, fbfront: fix connecting to backend

On Thursday, March 23, 2017 10:11:12 AM Boris Ostrovsky wrote:
> On 03/23/2017 08:52 AM, Juergen Gross wrote:
> > 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.
> >
> > Cc: [email protected]
> > Signed-off-by: Juergen Gross <[email protected]>
>
> Reviewed-by: Boris Ostrovsky <[email protected]>

Patch queued for 4.11, thanks.

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics