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Date:   Wed, 14 Dec 2022 09:01:24 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Leon Romanovsky <leon@kernel.org>
Cc:     Alexandra Kossovsky <Alexandra.Kossovsky@oktetlabs.ru>,
        Saeed Mahameed <saeedm@nvidia.com>,
        Maxim Mikityanskiy <maximmi@nvidia.com>, netdev@vger.kernel.org
Subject: Re: [PATCH] net/mlx5e: parameter to disable symmetric hash
Message-ID: <20221214090124.4c01a360@kernel.org>
In-Reply-To: <Y5nfPjloqVqmWPyn@gondor.oktetlabs.ru>
References: <Y5nfPjloqVqmWPyn@gondor.oktetlabs.ru>
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On Wed, 14 Dec 2022 17:35:42 +0300 Alexandra Kossovsky wrote:
> Some AF_XDP applications assume standard Topelitz hash when spreading
> traffic accross queues via RSS.  MLX5 driver always set "symmetric"
> bit, which results in unexpected queues for any particular connection.
> 
> With this patch is is possible to disable that symmetric bit via
> use_symmetric_hash module parameter, and use the standard Toeplitz hash
> with well-known predictable result, same as for other NICs.

This module param, OTOH, not okay..

[ https://lore.kernel.org/all/20221214085106.42a88df1@kernel.org/ ]