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Date: Tue, 21 Nov 2023 15:33:58 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Ahmed Zaki <ahmed.zaki@intel.com>
Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
 corbet@lwn.net, jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com,
 davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
 vladimir.oltean@nxp.com, andrew@lunn.ch, horms@kernel.org,
 mkubecek@suse.cz, willemdebruijn.kernel@gmail.com, gal@nvidia.com,
 alexander.duyck@gmail.com, linux-doc@vger.kernel.org, Wojciech Drewek
 <wojciech.drewek@intel.com>
Subject: Re: [PATCH net-next v6 2/7] net: ethtool: add support for
 symmetric-xor RSS hash
Message-ID: <20231121153358.3a6a09de@kernel.org>
In-Reply-To: <20231120205614.46350-3-ahmed.zaki@intel.com>
References: <20231120205614.46350-1-ahmed.zaki@intel.com>
	<20231120205614.46350-3-ahmed.zaki@intel.com>
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On Mon, 20 Nov 2023 13:56:09 -0700 Ahmed Zaki wrote:
> + * @data: Extension for the RSS hash function. Valid values are one of the
> + *	%RXH_HFUNC_*.

@data is way too generic. Can we call this key_xfrm? key_preproc?

> +/* RSS hash function data
> + * XOR the corresponding source and destination fields of each specified
> + * protocol. Both copies of the XOR'ed fields are fed into the RSS and RXHASH
> + * calculation.
> + */
> +#define	RXH_HFUNC_SYM_XOR	(1 << 0)

We need to mention somewhere that sym-xor is unsafe, per Alex's
comments.

> +++ b/include/uapi/linux/ethtool_netlink.h

You need to fill in the details in:

Documentation/networking/ethtool-netlink.rst
and
Documentation/netlink/specs/ethtool.yaml

Last but not least please keep the field check you moved to the drivers
in the core. Nobody will remember to check that other drivers added the
check as well.
-- 
pw-bot: cr