[PATCH] net: ucc_geth - fix Oops when changing number of buffers in the ring

[David Miller]

From: Christophe Leroy <christophe.leroy at c-s.fr>
Date: Fri,  3 May 2019 13:33:23 +0000 (UTC)

> When changing the number of buffers in the RX ring while the interface
> is running, the following Oops is encountered due to the new number
> of buffers being taken into account immediately while their allocation
> is done when opening the device only.
 ...
> This patch forbids the modification of the number of buffers in the
> ring while the interface is running.
> 
> Fixes: ac421852b3a0 ("ucc_geth: add ethtool support")
> Cc: stable at vger.kernel.org
> Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>

Applied and queued up for -stable.