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Date: Tue, 17 Oct 2023 13:19:57 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Ahmed Zaki <ahmed.zaki@intel.com>, netdev@vger.kernel.org,
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 linux-doc@vger.kernel.org, Wojciech Drewek <wojciech.drewek@intel.com>
Subject: Re: [PATCH net-next v4 1/6] net: ethtool: allow symmetric-xor RSS
 hash for any flow type
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On Tue, 17 Oct 2023 13:03:39 -0700 Alexander Duyck wrote:
> > > My thought would be to possibly just look at reducing your messaging
> > > to a warning from the driver if the inputs are not symmetric, but you
> > > have your symmetric xor hash function enabled.  
> >
> > With the restrictions (to be moved into ice_ethtool), the user is unable
> > to use non-symmetric inputs.  
> 
> I think a warning would make more sense than an outright restriction.
> You could warn on both the enabling if the mask is already unbalanced,
> or you could warn if the mask is set to be unbalanced after enabling
> your hashing.

Either it's a valid configuration or we should error out in the core.
Keep in mind that we can always _loosen_ the restriction, like you
asked for VLAN ID, but we can never _tighten_ it without breaking uAPI.
So error.