Subject: Re: [PATCH net 1/3] slip/slcan: added locking in wakeup function

From: Marc Kleine-Budde <[email-masked]>
Date: Thu, 19 Sep 2013 11:36:09 +0200

On 09/13/2013 07:37 PM, Andre Naujoks wrote:
> The locking is needed, since the the internal buffer for the CAN frames is
> changed during the wakeup call. This could cause buffer inconsistencies
> under high loads, especially for the outgoing short CAN packet skbuffs.
> 
> The needed locks led to deadlocks before commit
> "5ede52538ee2b2202d9dff5b06c33bfde421e6e4 tty: Remove extra wakeup from pty
> write() path", which removed the direct callback to the wakeup function from the
> tty layer.

What does that mean for older kernels?
(< 5ede52538ee2b2202d9dff5b06c33bfde421e6e4)

> As slcan.c is based on slip.c the issue in the original code is fixed, too.
> 
> Signed-off-by: Andre Naujoks <[email-masked]>
Acked-by: Marc Kleine-Budde  <[email-masked]>

Marc

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