Hi!

> We avoid 2 VLAs by using a pre-allocated field in dsa_switch. We also
> try to avoid dynamic allocation whenever possible (when using fewer than
> bits-per-long ports, which is the common case).
> 
> Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
> Link: http://lkml.kernel.org/r/20180505185145.GB32630@lunn.ch
> Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
> [kees: tweak commit subject and message slightly]
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
>  include/net/dsa.h |  3 +++
>  net/dsa/dsa2.c    | 14 ++++++++++++++
>  net/dsa/switch.c  | 22 ++++++++++------------
>  3 files changed, 27 insertions(+), 12 deletions(-)
> 
> diff --git a/include/net/dsa.h b/include/net/dsa.h
> index fdbd6082945d..461e8a7661b7 100644
> --- a/include/net/dsa.h
> +++ b/include/net/dsa.h
> @@ -259,6 +259,9 @@ struct dsa_switch {
>  	/* Number of switch port queues */
>  	unsigned int		num_tx_queues;
>  
> +	unsigned long		*bitmap;
> +	unsigned long		_bitmap;

This looks rather confusing. _bitmap -> bitmap_data? bitmap_bits?

Thanks,
									Pavel
-- 
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