Re: [added to the 3.18 stable tree] can: fix loss of CAN frames in raw_rcv

[Marc Kleine-Budde <mkl@pengutronix.de>]

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On 07/13/2015 03:43 PM, Sasha Levin wrote:
> From: Oliver Hartkopp <socketcan@hartkopp.net>
> 
> This patch has been added to the 3.18 stable tree. If you have any
> objections, please let us know.
> 
> ===============
> 
> [ Upstream commit 36c01245eb8046c16eee6431e7dbfbb302635fa8 ]
> 
> As reported by Manfred Schlaegl here
> 
>    http://marc.info/?l=linux-netdev&m=143482089824232&w=2
> 
> commit 514ac99c64b "can: fix multiple delivery of a single CAN frame for
> overlapping CAN filters" requires the skb->tstamp to be set to check for
> identical CAN skbs.
> 
> As net timestamping is influenced by several players (netstamp_needed and
> netdev_tstamp_prequeue) Manfred missed a proper timestamp which leads to
> CAN frame loss.
> 
> As skb timestamping became now mandatory for CAN related skbs this patch
> makes sure that received CAN skbs always have a proper timestamp set.
> Maybe there's a better solution in the future but this patch fixes the
> CAN frame loss so far.
> 
> Reported-by: Manfred Schlaegl <manfred.schlaegl@gmx.at>
> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
> Cc: linux-stable <stable@vger.kernel.org>
> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

You and Oliver decided that this is not relevant for 3.18...See Oliver's
mail:

> this patch fixes commit 514ac99c64b "can: fix multiple delivery of a single 
> CAN frame for overlapping CAN filters" which is currently not on your list for 
> 3.18.
> 
> Indeed I would suggest to omit either commit 514ac99c64b and the patch below 
> for 3.18 stable.
> 
> Commit 514ac99c64b changes the number of returned frames in some cases and by 
> now developers can trust on the fact that this behaviour change comes with 
> Linux 4.1.
> 
> So nothing breaks when we omit commit 514ac99c64b and 36c01245eb804 for 3.18.
> 
> The fact that the patch below emerged on the stable ML is that it is relevant 
> for 4.1 which was released in this phase.

Or have I missed something?

Marc

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